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Sample records for affect sea level

  1. Does the Maritime Continent region affect sea level change of the eastern Indian Ocean?

    NASA Astrophysics Data System (ADS)

    Llovel, W.; Lee, T.

    2014-12-01

    The Maritime Continent region, in particular, the Indonesian Sea, regulates the oceanic communication between the Pacific and Indian Oceans. Previous studies suggest that the freshwater transported from the South China Sea to the Indonesian Sea affects the magnitude and structure of the Indonesian throughflow, and the strong tidal mixing in the Indonesian Sea alters the time mean vertical structure of the water mass carried from the Pacific to the Indian Oceans. Sea level changes in the eastern Indian Ocean is known to be affected by those in the northwestern Pacific via coastal Kelvin wave propagation through the Indonesian Sea. However, whether the Maritime Continent region influences sea level changes in the eastern Indian Ocean has not been investigated. In this study, we used Argo floats and satellite altimeter data to study the near decadal change of sea level during the 2005-2013 period. We found that the steric sea level change in eastern Indian Ocean cannot be fully explained by either local forcing or the transmission of steric signal from the western Pacific. This implicates the potential role of the Maritime Continent region in regulating sea level changes in the eastern Indian Ocean.

  2. Neutral models as a way to evaluate the Sea Level Affecting Marshes Model (SLAMM)

    EPA Science Inventory

    A commonly used landscape model to simulate wetland change – the Sea Level Affecting Marshes Model(SLAMM) – has rarely been explicitly assessed for its prediction accuracy. Here, we evaluated this model using recently proposed neutral models – including the random constraint matc...

  3. Temperature and dietary starch level affected protein but not starch digestibility in gilthead sea bream juveniles.

    PubMed

    Couto, A; Enes, P; Peres, H; Oliva-Teles, A

    2012-06-01

    A study was carried out with gilthead sea bream juveniles to assess the effect of water temperature (18 and 25°C) and dietary pregelatinized starch level (10, 20 and 30%) on digestibility of protein and starch and on the activity of proteolytic and amylolytic enzymes. ADC of pregelatinized starch was very high (>99%) irrespectively of dietary inclusion level, and it was not affected by water temperature. ADC of protein was also high (>90%) but improved at the higher water temperature. Dietary starch interacted with protein digestibility, which decreased as dietary starch level increased. Temperature affected both acid and basic protease activities, with acid protease activity being higher at 25°C and basic protease activity being higher at 18°C. However, total proteolytic activity and amylase activities were not affected by water temperature. Dietary carbohydrate exerted no effect on proteolytic or amylolitic activities. It is concluded that gilthead sea bream juveniles digest pregelatinized starch very efficiently irrespective of water temperature, due to adjustments of amylase activity to cope with temperature differences. Pregelatinized starch interacts negatively with protein digestibility, with the ADC of protein decreasing as dietary starch levels increase.

  4. Sea Level Affecting Marshes Model (SLAMM) ‐ New functionality for predicting changes in distribution of submerged aquatic vegetation in response to sea level rise

    USGS Publications Warehouse

    Lee II, Henry; Reusser, Deborah A.; Frazier, Melanie R; McCoy, Lee M; Clinton, Patrick J.; Clough, Jonathan S.

    2014-01-01

    The “Sea‐Level Affecting Marshes Model” (SLAMM) is a moderate resolution model used to predict the effects of sea level rise on marsh habitats (Craft et al. 2009). SLAMM has been used extensively on both the west coast (e.g., Glick et al., 2007) and east coast (e.g., Geselbracht et al., 2011) of the United States to evaluate potential changes in the distribution and extent of tidal marsh habitats. However, a limitation of the current version of SLAMM, (Version 6.2) is that it lacks the ability to model distribution changes in seagrass habitat resulting from sea level rise. Because of the ecological importance of SAV habitats, U.S. EPA, USGS, and USDA partnered with Warren Pinnacle Consulting to enhance the SLAMM modeling software to include new functionality in order to predict changes in Zostera marina distribution within Pacific Northwest estuaries in response to sea level rise. Specifically, the objective was to develop a SAV model that used generally available GIS data and parameters that were predictive and that could be customized for other estuaries that have GIS layers of existing SAV distribution. This report describes the procedure used to develop the SAV model for the Yaquina Bay Estuary, Oregon, appends a statistical script based on the open source R software to generate a similar SAV model for other estuaries that have data layers of existing SAV, and describes how to incorporate the model coefficients from the site‐specific SAV model into SLAMM to predict the effects of sea level rise on Zostera marina distributions. To demonstrate the applicability of the R tools, we utilize them to develop model coefficients for Willapa Bay, Washington using site‐specific SAV data.

  5. Sea level variation

    NASA Technical Reports Server (NTRS)

    Douglas, Bruce C.

    1992-01-01

    Published values for the long-term, global mean sea level rise determined from tide gauge records range from about one to three mm per year. The scatter of the estimates appears to arise largely from the use of data from gauges located at convergent tectonic plate boundaries where changes of land elevation give fictitious sea level trends, and the effects of large interdecadal and longer sea level variations on short (less than 50+ years) or sappy records. In addition, virtually all gauges undergo subsidence or uplift due to isostatic rebound from the last deglaciation at a rate comparable to or greater than the secular rise of sea level. Modeling rebound by the ICE-3G model of Tushingham and Peltier (1990) and avoiding tide gauge records in areas of converging tectonic plates produces a highly consistent set of long sea level records. A global set of 21 such stations in nine oceanic regions with an average record length of 76 years during the period 1880-1980 yields the global sea level rise value 1.8 mm/year +/- 0.1. Greenhouse warming scenarios commonly forecast an additional acceleration of global sea level in the next 5 or 6+ decades in the range 0.1-0.2 mm/yr2. Because of the large power at low frequencies in the sea level spectrum, very long tide gauge records (75 years minimum) have been examined for past apparent sea level acceleration. For the 80-year period 1905-1985, 23 essentially complete tide gauge records in 10 geographic groups are available for analysis. These yielded the apparent global acceleration -0.011 (+/- 0.012) mm/yr2. A larger, less uniform set of 37 records in the same 10 groups with 92 years average length covering the 141 years from 1850-1991 gave 0.001 (+/- 0.008) mm/yr2. Thus there is no evidence for an apparent acceleration in the past 100+ years that is significant either statistically, or in comparison to values associated with global warming. Unfortunately, the large interdecadal fluctuations of sea level severely affect

  6. Projecting future sea level

    USGS Publications Warehouse

    Cayan, Daniel R.; Bromirski, Peter; Hayhoe, Katharine; Tyree, Mary; Dettinger, Mike; Flick, Reinhard

    2006-01-01

    California’s coastal observations and global model projections indicate that California’s open coast and estuaries will experience increasing sea levels over the next century. Sea level rise has affected much of the coast of California, including the Southern California coast, the Central California open coast, and the San Francisco Bay and upper estuary. These trends, quantified from a small set of California tide gages, have ranged from 10–20 centimeters (cm) (3.9–7.9 inches) per century, quite similar to that estimated for global mean sea level. So far, there is little evidence that the rate of rise has accelerated, and the rate of rise at California tide gages has actually flattened since 1980, but projections suggest substantial sea level rise may occur over the next century. Climate change simulations project a substantial rate of global sea level rise over the next century due to thermal expansion as the oceans warm and runoff from melting land-based snow and ice accelerates. Sea level rise projected from the models increases with the amount of warming. Relative to sea levels in 2000, by the 2070–2099 period, sea level rise projections range from 11–54 cm (4.3–21 in) for simulations following the lower (B1) greenhouse gas (GHG) emissions scenario, from 14–61 cm (5.5–24 in) for the middle-upper (A2) emission scenario, and from 17–72 cm (6.7–28 in) for the highest (A1fi) scenario. In addition to relatively steady secular trends, sea levels along the California coast undergo shorter period variability above or below predicted tide levels and changes associated with long-term trends. These variations are caused by weather events and by seasonal to decadal climate fluctuations over the Pacific Ocean that in turn affect the Pacific coast. Highest coastal sea levels have occurred when winter storms and Pacific climate disturbances, such as El Niño, have coincided with high astronomical tides. This study considers a range of projected future

  7. Global sea level rise

    SciTech Connect

    Douglas, B.C. )

    1991-04-15

    Published values for the long-term, global mean sea level rise determined from tide gauge records exhibit considerable scatter, from about 1 mm to 3 mm/yr. This disparity is not attributable to instrument error; long-term trends computed at adjacent sites often agree to within a few tenths of a millimeter per year. Instead, the differing estimates of global sea level rise appear to be in large part due to authors' using data from gauges located at convergent tectonic plate boundaries, where changes of land elevation give fictitious sea level trends. In addition, virtually all gauges undergo subsidence or uplift due to postglacial rebound (PGR) from the last deglaciation at a rate comparable to or greater than the secular rise of sea level. Modeling PGR by the ICE-3G model of Tushingham and Peltier (1991) and avoiding tide gauge records in areas of converging tectonic plates produces a highly consistent set of long sea level records. The value for mean sea level rise obtained from a global set of 21 such stations in nine oceanic regions with an average record length of 76 years during the period 1880-1980 is 1.8 mm/yr {plus minus} 0.1. This result provides confidence that carefully selected long tide gauge records measure the same underlying trend of sea level and that many old tide gauge records are of very high quality.

  8. Sea level change

    SciTech Connect

    Meier, M.F.

    1996-12-31

    The IPCC (Intergovernmental Panel on Climate Change) 1995 Scientific Assessment, Chapter 7. Sea Level Change, presents a modest revision of the similar chapter in the 1990 Assessment. Principal conclusions on observed sea-level change and the principal terms in the sea-level equation (ocean thermal expansion, glaciers, ice sheets, and land hydrology), including our knowledge of the present-day (defined as the 20th Century) components of sea-level rise, and projections of these for the future, are presented here. Some of the interesting glaciological problems which are involved in these studies are discussed in more detail. The emphasis here is on trends over decades to a century, not on shorter variations nor on those of the geologic past. Unfortunately, some of the IPCC projections had not been agreed at the time of writing of this paper, and these projections will not be given here. 15 refs., 2 figs.

  9. Contemporary sea level rise.

    PubMed

    Cazenave, Anny; Llovel, William

    2010-01-01

    Measuring sea level change and understanding its causes has considerably improved in the recent years, essentially because new in situ and remote sensing observations have become available. Here we report on most recent results on contemporary sea level rise. We first present sea level observations from tide gauges over the twentieth century and from satellite altimetry since the early 1990s. We next discuss the most recent progress made in quantifying the processes causing sea level change on timescales ranging from years to decades, i.e., thermal expansion of the oceans, land ice mass loss, and land water-storage change. We show that for the 1993-2007 time span, the sum of climate-related contributions (2.85 +/- 0.35 mm year(-1)) is only slightly less than altimetry-based sea level rise (3.3 +/- 0.4 mm year(-1)): approximately 30% of the observed rate of rise is due to ocean thermal expansion and approximately 55% results from land ice melt. Recent acceleration in glacier melting and ice mass loss from the ice sheets increases the latter contribution up to 80% for the past five years. We also review the main causes of regional variability in sea level trends: The dominant contribution results from nonuniform changes in ocean thermal expansion.

  10. Caribbean Sea Level Network

    NASA Astrophysics Data System (ADS)

    von Hillebrandt-Andrade, C.; Crespo Jones, H.

    2012-12-01

    Over the past 500 years almost 100 tsunamis have been observed in the Caribbean and Western Atlantic, with at least 3510 people having lost their lives to this hazard since 1842. Furthermore, with the dramatic increase in population and infrastructure along the Caribbean coasts, today, millions of coastal residents, workers and visitors are vulnerable to tsunamis. The UNESCO IOC Intergovernmental Coordination Group for Tsunamis and other Coastal Hazards for the Caribbean and Adjacent Regions (CARIBE EWS) was established in 2005 to coordinate and advance the regional tsunami warning system. The CARIBE EWS focuses on four areas/working groups: (1) Monitoring and Warning, (2) Hazard and Risk Assessment, (3) Communication and (4) Education, Preparedness and Readiness. The sea level monitoring component is under Working Group 1. Although in the current system, it's the seismic data and information that generate the initial tsunami bulletins, it is the data from deep ocean buoys (DARTS) and the coastal sea level gauges that are critical for the actual detection and forecasting of tsunamis impact. Despite multiple efforts and investments in the installation of sea level stations in the region, in 2004 there were only a handful of sea level stations operational in the region (Puerto Rico, US Virgin Islands, Bermuda, Bahamas). Over the past 5 years there has been a steady increase in the number of stations operating in the Caribbean region. As of mid 2012 there were 7 DARTS and 37 coastal gauges with additional ones being installed or funded. In order to reach the goal of 100 operational coastal sea level stations in the Caribbean, the CARIBE EWS recognizes also the importance of maintaining the current stations. For this, a trained workforce in the region for the installation, operation and data analysis and quality control is considered to be critical. Since 2008, three training courses have been offered to the sea level station operators and data analysts. Other

  11. Molecular signatures of Pleistocene sea-level changes that affected connectivity among freshwater shrimp in Indo-Australian waters.

    PubMed

    De Bruyn, Mark; Mather, Peter B

    2007-10-01

    A major paradigm in evolutionary biology asserts that global climate change during the Pleistocene often led to rapid and extensive diversification in numerous taxa. Recent phylogenetic data suggest that past climatic oscillations may have promoted long-distance marine dispersal in some freshwater crustacea from the Indo-Australian Archipelago (IAA). Whether this pattern is common, and whether similar processes are acting on diversification below the species level is unknown. We used nuclear and mitochondrial molecular variation in a freshwater-dependent decapod crustacean (Macrobrachium rosenbergii), sampled widely from the IAA, to assess the impact of Pleistocene sea-level changes on lineage diversification in this species. Fitting of an isolation with migration model enabled us to reject ongoing migration among lineages, and results indicate that isolation among both mainland-mainland and mainland-island lineages arose during the mid-Pleistocene. Our data suggest a scenario of widespread marine dispersal during Pleistocene glacial maxima (in support of the 'Pleistocene marine dispersal hypothesis') when sea levels were low, and geographical distances between fresh watersheds were greatly reduced, followed by increased isolation as sea levels subsequently rose.

  12. Understanding Sea Level Changes

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.

    2004-01-01

    Today more than 100 million people worldwide live on coastlines within one meter of mean sea level; any short-term or long-term sea level change relative to vertical ground motion is of great societal and economic concern. As palm-environment and historical data have clearly indicated the existence and prevalence of such changes in the past, new scientific information regarding to the nature and causes and a prediction capability are of utmost importance for the future. The 10-20 cm global sea-level rise recorded over the last century has been broadly attributed to two effects: (1) the steric effect (thermal expansion and salinity-density compensation of sea water) following global climate; (2) mass-budget changes due to a number of competing geophysical and hydrological processes in the Earth-atmosphere-hydrosphere-cryosphere system, including water exchange from polar ice sheets and mountain glaciers to the ocean, atmospheric water vapor and land hydrological variations, and anthropogenic effects such as water impoundment in artificial reservoirs and extraction of groundwater, all superimposed on the vertical motions of solid Earth due to tectonics, rebound of the mantle from past and present deglaciation, and other local ground motions. As remote-sensing tools, a number of space geodetic measurements of sea surface topography (e.g., TOPEX/Poseidon, Jason), ice mass (e.g., ICESat), time-variable gravity (e.g. GRACE), and ground motions (SLR, VLBI, GPS, InSAR, Laser altimetry, etc.) become directly relevant. Understanding sea level changes "anywhere, anytime" in a well-defined terrestrial reference frame in terms of climate change and interactions among ice masses, oceans, and the solid Earth, and being able to predict them, emerge as one of the scientific challenges in the Solid Earth Science Working Group (SESWG, 2003) conclusions.

  13. Numerical Weather Prediction and Earth System Prediction to Better Understand Sea Level Rise/Coastal Issues as They Affect Readiness

    DTIC Science & Technology

    2011-11-01

    National Unified Operational Prediction Capability NUOPC 19 Cancelled  Sor&es  during  OIF   Dust   Storm   (Based  on  LCDR  Jake...Global Atmospheric Prediction System (NOGAPS) •  Coupled Ocean Atmosphere Mesoscale Prediction System ( COAMPS ) •  Navy Coastal Ocean Model (NCOM... Storms •  Arctic •  Sea Level •  Perma frost •  Military preparedness –  Equipment –  Facilities –  Training National Unified Operational

  14. Interactions between barrier islands and backbarrier marshes affect island system response to sea level rise: Insights from a coupled model

    NASA Astrophysics Data System (ADS)

    Walters, David; Moore, Laura J.; Duran Vinent, Orencio; Fagherazzi, Sergio; Mariotti, Giulio

    2014-09-01

    Interactions between backbarrier marshes and barrier islands will likely play an important role in determining how low-lying coastal systems respond to sea level rise and changes in storminess in the future. To assess the role of couplings between marshes and barrier islands under changing conditions, we develop and apply a coupled barrier island-marsh model (GEOMBEST+) to assess the impact of overwash deposition on backbarrier marsh morphology and of marsh morphology on rates of island migration. Our model results suggest that backbarrier marsh width is in a constant state of change until either the backbarrier basin becomes completely filled or backbarrier marsh deposits have completely eroded away. Results also suggest that overwash deposition is an important source of sediment, which allows existing narrow marshes to be maintained in a long-lasting alternate state (~500 m wide in the Virginia Barrier Islands) within a range of conditions under which they would otherwise disappear. The existence of a narrow marsh state is supported by observations of backbarrier marshes along the eastern shore of Virginia. Additional results suggest that marshes reduce accommodation in the backbarrier bay, which, in turn, decreases island migration rate. As climate change results in sea level rise, and the increased potential for intense hurricanes resulting in overwash, it is likely that these couplings will become increasingly important in determining future system behavior.

  15. Late Pleistocene Sea Level Stack

    NASA Astrophysics Data System (ADS)

    Spratt, R. M.; Lisiecki, L. E.

    2014-12-01

    Sea level reconstructions have been created using wide variety of proxies and models. The accuracy of individual sea level reconstructions is limited by measurement, noise, local variations in salinity and temperature, and the assumptions particular to each reconstruction. To address these limitations, we have created a sea level stack (average) which increases the signal-to-noise ratio of sea level estimates by combining 5-7 sea level reconstructions over the last 800 kyr. Principal Component analysis (PCA) of seven sea level records from 0-430 kyr ago shows that 82% of the variance in these records is explained by their first principal component (i.e., the stack). Additionally, a stack of just the 5 longer records that extends to 800 kyr closely matches the timing and amplitude of our seven-record mean. We find that the mean sea level estimate for Marine Isotope Stage (MIS) 5e is 0-4 m above modern, and that the standard deviation of individual estimates is 11 m. Mean sea level estimates for MIS 11 are 12-16 m above modern with a standard deviation of 30 m. Due to the large variability between individual reconstructions, our sea level stack may provide more robust sea level estimates than any single technique.

  16. Two Sea-Level Challenges

    NASA Astrophysics Data System (ADS)

    Galvin, C.

    2008-12-01

    "No place on the sandy ocean shores of the world has been shown to be eroding because of sea level rise." This statement appeared nearly 19 years ago in bold print at the top of the page in a brief article published in Shore and Beach (Galvin,1990). The term "sea level rise" was defined in 1990 as follows: "In this statement, "sea level rise" has the meaning that the average person on the street usually attaches to that term. That is, sea level is rising; not, as in some places like the Mississippi River delta, land level is sinking." While still a subject of controversy, it is now (2008) increasingly plausible (Tornqvist et al,2008) that damage from Hurricane Katrina was significantly worse on the Mississippi River delta because floodwaters exploited wetlands and levees whose elevations had been lowered by decades of compaction in the underlying soil. (1) "Sea level" commonly appears in the literature as "relative sea level rise", occurring that way in 711 publications between 1980 and 2009 (GeoRef database on 8 Sep 08). "Relative sea level rise" does not appear in the 2005 AGI Glossary. The nearest Glossary term is "relative change in sea level", but that term occurs in only 12 publications between 1980 and 2009. The Glossary defines this term in a sequence stratigraphy sense, which infers that "relative sea level rise" is the sum of bottom subsidence and eustatic sea level rise. In plain English, "relative sea level rise" means "water depth increase". For present day coastal environments, "relative sea level rise" is commonly used where eustatic sea level rise is less than subsidence, that is, where the magnitude of actual sea level rise is smaller than the magnitude of subsidence. In that situation, "relative sea level rise" misleads both the average person and the scientist who is not a coastal geologist. Thus, the first challenge is to abandon "relative sea level rise" in favor of "water depth increase", in order that the words accurately descibe what happens

  17. Causes for contemporary regional sea level changes.

    PubMed

    Stammer, Detlef; Cazenave, Anny; Ponte, Rui M; Tamisiea, Mark E

    2013-01-01

    Regional sea level changes can deviate substantially from those of the global mean, can vary on a broad range of timescales, and in some regions can even lead to a reversal of long-term global mean sea level trends. The underlying causes are associated with dynamic variations in the ocean circulation as part of climate modes of variability and with an isostatic adjustment of Earth's crust to past and ongoing changes in polar ice masses and continental water storage. Relative to the coastline, sea level is also affected by processes such as earthquakes and anthropogenically induced subsidence. Present-day regional sea level changes appear to be caused primarily by natural climate variability. However, the imprint of anthropogenic effects on regional sea level-whether due to changes in the atmospheric forcing or to mass variations in the system-will grow with time as climate change progresses, and toward the end of the twenty-first century, regional sea level patterns will be a superposition of climate variability modes and natural and anthropogenically induced static sea level patterns. Attribution and predictions of ongoing and future sea level changes require an expanded and sustained climate observing system.

  18. Sea level rise and coastal erosion

    NASA Astrophysics Data System (ADS)

    Leatherman, S. P.; Zhang, K.; Douglas, B. C.

    2003-04-01

    One of the most certain consequences of global warming is an increase of global (eustatic) sea level. The resulting inundation from rising seas will heavily impact low-lying areas; at least 100 million persons live within one meter of mean sea level and are at increased risk in the coming decades. The very existence of some island states and deltaic coasts is threatened by sea level rise. An additional threat affecting some of the most heavily developed and economically valuable real estate will come from an exacerbation of sandy beach erosion. As the beach is lost, fixed structures nearby are increasingly exposed to the direct impact of storm waves, and will ultimately be damaged or destroyed unless expensive protective measures are taken. It has long been speculated that the underlying rate of long-term sandy beach erosion is two orders of magnitude greater than the rate of rise of sea level, so that any significant increase of sea level has dire consequences for coastal inhabitants. We present an analysis of a large and consistent database of shoreline positions and sea levels to show that there is an underlying highly multiplicative relation of sandy beach erosion to sea level rise. This result means that the already-severe coastal erosion problems witnessed in the 20th century will be exacerbated in the 21st century under plausible global warming scenarios.

  19. Sea Level Rise in Tuvalu

    NASA Astrophysics Data System (ADS)

    Lin, C. C.; Ho, C. R.; Cheng, Y. H.

    2012-04-01

    Most people, especially for Pacific Islanders, are aware of the sea level change which may caused by many factors, but no of them has deeper sensation of flooding than Tuvaluan. Tuvalu, a coral country, consists of nine low-lying islands in the central Pacific between the latitudes of 5 and 10 degrees south, has the average elevation of 2 meters (South Pacific Sea Level and Climate Monitoring Project, SPSLCMP report, 2006) up to sea level. Meanwhile, the maximum sea level recorded was 3.44m on February 28th 2006 that damaged Tuvaluan's property badly. Local people called the flooding water oozes up out of the ground "King Tide", that happened almost once or twice a year, which destroyed the plant, polluted their fresh water, and forced them to colonize to some other countries. The predictable but uncontrollable king tide had been observed for a long time by SPSLCMP, but some of the uncertainties which intensify the sea level rise need to be analyzed furthermore. In this study, a span of 18 years of tide gauge data accessed from Sea Level Fine Resolution Acoustic Measuring Equipment (SEAFRAME) are compared with the satellite altimeter data accessed from Archiving Validation and Interpretation of Satellite Data in Oceanography (AVISO). All above are processed under the limitation of same time and spatial range. The outcome revealed a 9.26cm difference between both. After the tide gauge data shifted to the same base as altimeter data, the results showed the unknown residuals are always positive under the circumstances of the sea level rise above 3.2m. Apart from uncertainties in observing, the residual reflected unknown contributions. Among the total case number of sea level rise above 3.2m is 23 times, 22 of which were recorded with oceanic warm eddy happened simultaneously. The unknown residual seems precisely matched with oceanic warm eddies and illustrates a clear future approach for Tuvaluan to care for.

  20. Intermittent sea-level acceleration

    NASA Astrophysics Data System (ADS)

    Olivieri, M.; Spada, G.

    2013-10-01

    Using instrumental observations from the Permanent Service for Mean Sea Level (PSMSL), we provide a new assessment of the global sea-level acceleration for the last ~ 2 centuries (1820-2010). Our results, obtained by a stack of tide gauge time series, confirm the existence of a global sea-level acceleration (GSLA) and, coherently with independent assessments so far, they point to a value close to 0.01 mm/yr2. However, differently from previous studies, we discuss how change points or abrupt inflections in individual sea-level time series have contributed to the GSLA. Our analysis, based on methods borrowed from econometrics, suggests the existence of two distinct driving mechanisms for the GSLA, both involving a minority of tide gauges globally. The first effectively implies a gradual increase in the rate of sea-level rise at individual tide gauges, while the second is manifest through a sequence of catastrophic variations of the sea-level trend. These occurred intermittently since the end of the 19th century and became more frequent during the last four decades.

  1. USACE Extreme Sea levels

    DTIC Science & Technology

    2014-03-14

    into Extreme Water Level Characterization 9 September 2013 Attendees: Heidi Moritz, Kate White, Jonathan Simm, Robert Nicholls, Peter Hawkes...adaptation. Robert Nicholls raised the question of how well do we feel that we understand the present extreme climate? We should start with this area...the peer-review and acceptance process for a journal paper. Robert suggested that most of the papers which are needed for an analysis today may be

  2. Visualizing Sea Level Rise with Augmented Reality

    NASA Astrophysics Data System (ADS)

    Kintisch, E. S.

    2013-12-01

    Looking Glass is an application on the iPhone that visualizes in 3-D future scenarios of sea level rise, overlaid on live camera imagery in situ. Using a technology known as augmented reality, the app allows a layperson user to explore various scenarios of sea level rise using a visual interface. Then the user can see, in an immersive, dynamic way, how those scenarios would affect a real place. The first part of the experience activates users' cognitive, quantitative thinking process, teaching them how global sea level rise, tides and storm surge contribute to flooding; the second allows an emotional response to a striking visual depiction of possible future catastrophe. This project represents a partnership between a science journalist, MIT, and the Rhode Island School of Design, and the talk will touch on lessons this projects provides on structuring and executing such multidisciplinary efforts on future design projects.

  3. Sea Level Change, A Fundamental Process When Interpreting Coastal Geology and Geography.

    ERIC Educational Resources Information Center

    Zeigler, John M.

    1985-01-01

    Discusses the meaning of sea level change and identifies the major factors responsible for this occurrence. Elaborates on the theory and processes involved in indirect measurement of changes in sea volume. Also explains how crustal movement affects sea level. (ML)

  4. Dynamics of sea level variations in the coastal Red Sea

    NASA Astrophysics Data System (ADS)

    Churchill, James; Abulnaja, Yasser; Nellayaputhenpeedika, Mohammedali; Limeburner, Richard; Lentz, Steven

    2016-04-01

    Sea level variations in the central Red Sea coastal zone span a range of roughly 1.2 m. Though relatively small, these water level changes can significantly impact the environment over the shallow reef tops prevalent in the central Red Sea, altering the water depth by a factor or two or more. While considerable scientific work has been directed at tidal and seasonal variations of Red Sea water level, very little attention has been given to elevation changes in an 'intermediate' frequency band, with periods of 2-30 d, even though motions in this band account for roughly half of the sea level variance in central Red Sea. We examined the sea level signal in this band using AVISO sea level anomaly (SLA) data, COARDAS wind data and measurements from pressure sensors maintained for more than five years at a number of locations in Saudi Arabian coastal waters. Empirical orthogonal function analysis of the SLA data indicates that longer-period (10-30 d) sea level variations in the intermediate band are dominated by coherent motions in a single mode that extends over most of the Red Sea axis. Idealized model results indicate that this large-scale mode of sea level motion is principally due to variations in the large-scale gradient of the along-axis wind. Our analysis indicates that coastal sea level motions at shorter periods (2-10 d) are principally generated by a combination of direct forcing by the local wind stress and forcing associated with large-scale wind stress gradients. However, also contributing to coastal sea level variations in the intermediate frequency band are mesoscale eddies, which are prevalent throughout the Red Sea basin, have a sea level signal of 10's of cm and produce relatively small-scale (order 50 km) changes in coastal sea level.

  5. Sea Level Variability in the Mediterranean

    NASA Astrophysics Data System (ADS)

    Zerbini, S.; Bruni, S.; del Conte, S.; Errico, M.; Petracca, F.; Prati, C.; Raicich, F.; Santi, E.

    2015-12-01

    Tide gauges measure local sea-level relative to a benchmark on land, therefore the interpretation of these measurements can be limited by the lack of appropriate knowledge of vertical crustal motions. The oldest sea-level records date back to the 18th century; these observations are the only centuries-old data source enabling the estimate of historical sea-level trends/variations. In general, tide gauge benchmarks were not frequently levelled, except in those stations where natural and/or anthropogenic subsidence was a major concern. However, in most cases, it is difficult to retrieve the historical geodetic levelling data. Space geodetic techniques, such as GNSS, Doris and InSAR are now providing measurements on a time and space-continuous basis, giving rise to a large amount of different data sets. The vertical motions resulting from the various analyses need to be compared and best exploited for achieving reliable estimates of sea level variations. In the Mediterranean area, there are a few centennial tide gauge records; our study focuses, in particular, on the Italian time series of Genoa, Marina di Ravenna, Venice and Trieste. Two of these stations, Marina di Ravenna and Venice, are affected by both natural and anthropogenic subsidence, the latter was particularly intense during a few decades of the 20th century because of ground fluids withdrawal. We have retrieved levelling data of benchmarks at and/or close to the tide gauges from the end of 1800 and, for the last couple of decades, also GPS and InSAR height time series in close proximity of the stations. By using an ensemble of these data, modelling of the long-period non-linear behavior of subsidence was successfully accomplished. After removal of the land vertical motions, the linear long period sea-level rates of all stations are in excellent agreement. Over the last two decades, the tide gauge rates were also compared with those obtained by satellite radar altimetry data.

  6. Ice sheet systems and sea level change.

    NASA Astrophysics Data System (ADS)

    Rignot, E. J.

    2015-12-01

    Modern views of ice sheets provided by satellites, airborne surveys, in situ data and paleoclimate records while transformative of glaciology have not fundamentally changed concerns about ice sheet stability and collapse that emerged in the 1970's. Motivated by the desire to learn more about ice sheets using new technologies, we stumbled on an unexplored field of science and witnessed surprising changes before realizing that most were coming too fast, soon and large. Ice sheets are integrant part of the Earth system; they interact vigorously with the atmosphere and the oceans, yet most of this interaction is not part of current global climate models. Since we have never witnessed the collapse of a marine ice sheet, observations and exploration remain critical sentinels. At present, these observations suggest that Antarctica and Greenland have been launched into a path of multi-meter sea level rise caused by rapid climate warming. While the current loss of ice sheet mass to the ocean remains a trickle, every mm of sea level change will take centuries of climate reversal to get back, several major marine-terminating sectors have been pushed out of equilibrium, and ice shelves are irremediably being lost. As glaciers retreat from their salty, warm, oceanic margins, they will melt away and retreat slower, but concerns remain about sea level change from vastly marine-based sectors: 2-m sea level equivalent in Greenland and 23-m in Antarctica. Significant changes affect 2/4 marine-based sectors in Greenland - Jakobshavn Isb. and the northeast stream - with Petermann Gl. not far behind. Major changes have affected the Amundsen Sea sector of West Antarctica since the 1980s. Smaller yet significant changes affect the marine-based Wilkes Land sector of East Antarctica, a reminder that not all marine-based ice is in West Antarctica. Major advances in reducing uncertainties in sea level projections will require massive, interdisciplinary efforts that are not currently in place

  7. Sea level trends and interannual variability in the Caribbean Sea

    NASA Astrophysics Data System (ADS)

    Torres, R.; Tsimplis, M.

    2012-04-01

    Sea level trends and interannual variability has been investigated in the Caribbean Sea using altimetry and tide gauge time series from 19 stations. Relative sea level trends range between -2.0 and 10.7 mm/y depending on the length of the available record. Records from stations longer than 40 years converge toward values between 1.2 - 5.2 mm/yr, still a significant range which in some stations is less and in some other significantly larger than the global average. The longest station, Cristobal (102 years) shows a trend of 1.9 mm/yr and, in addition a significant acceleration of 1.6±0.3 mm/y/cy. The observed sea level trends are not affected by the atmospheric pressure effect, within the levels of significance. They are also the same (within the levels of significance) at all seasons. Altimetry shows trends (over 18 years of data) with values up to 5.2 mm/y. In some areas the values are statistically insignificant, but at no areas statistically significant negative values are found. Steric trends from the top 800 m (over the period of altimetric observations) have a basin average trend of 1 mm/y, but it shows large spatial variability with negative trends of -7 mm/y in the Yucatan Basin and positive trends up to 4.9 mm/y in the Venezuela Basin. Decadal trends were found to vary significantly at tide-gauge records as well as altimetric and steric measurements. We further explore the residual interannual variability by comparison with surface wind and climatic indices. This analysis is supported by the Lloyd's Register Trust Fund project Marine Extremes.

  8. Estuaries May Face Increased Parasitism as Sea Levels Rise

    NASA Astrophysics Data System (ADS)

    Wendel, JoAnna

    2014-12-01

    Invertebrates in estuaries could be at a greater risk of parasitism as climate change causes sea levels to rise. A new paper published 8 December in Proceedings of the National Academy of Sciences of the United States of America (doi:10.1073/pnas.1416747111) describes how rapid sea level rise in the Holocene affected the population of parasitic flatworms called trematodes.

  9. Sea-Level Projections from the SeaRISE Initiative

    NASA Technical Reports Server (NTRS)

    Nowicki, Sophie; Bindschadler, Robert

    2011-01-01

    SeaRISE (Sea-level Response to Ice Sheet Evolution) is a community organized modeling effort, whose goal is to inform the fifth IPCC of the potential sea-level contribution from the Greenland and Antarctic ice sheets in the 21st and 22nd century. SeaRISE seeks to determine the most likely ice sheet response to imposed climatic forcing by initializing an ensemble of models with common datasets and applying the same forcing to each model. Sensitivity experiments were designed to quantify the sea-level rise associated with a change in: 1) surface mass balance, 2) basal lubrication, and 3) ocean induced basal melt. The range of responses, resulting from the multi-model approach, is interpreted as a proxy of uncertainty in our sea-level projections. http://websrv.cs .umt.edu/isis/index.php/SeaRISE_Assessment.

  10. CO2 and sea level

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    There is considerable discussion currently about the potential effects of carbon dioxide build-up in the atmosphere over the next several decades. The sources of information are two Government funded reports, one by the National Research Council (NRC), the other by the Environment Protection Agency (EPA), both were released within the last five months. The reports were described recently as being conservative, although the consequences of the resulting greenhouse effects are deemed inevitable. Atmospheric warming on a global scale of as much as 5°C cannot be avoided, only perhaps delayed by a few years at best (Environ. Sci. Technol, 18, 45A-46A, 1984). The cause is the burning of fossil fuels. Oil will not be too important because its supplies are predictably exhausted on the time scale of 50-100 years. Coal burning is considered as the main source of carbon dioxide. Among the more spectacular results of a global temperature rise over the next 100 years is the expected rise in sea level of a minimum of 70 cm (Oceanus, Winter, 1983/84). If the West Antarctic Ice Sheet breaks up and melts, the rise could be in the several meter range. Sea level rose only 15 cm in the past century.

  11. Demographic responses to sea level rise in California

    SciTech Connect

    Constable, A. |; Van Arsdol, M.D. Jr.; Sherman, D.J.; Wang, J.; McMullin-Messier, P.A.; Rollin, L.

    1996-12-31

    Human consequences of sea level rise in California coastal counties reflect increasing population densities. Populations of coastal counties potentially affected by sea level rise are projected to increase from 26.2 million persons in 1990 to 63.3 million persons in 2040. Urbanization dominates Los Angeles and the South Coast and San Francisco Bay and Delta regions. California shoreline populations subject to potential disruption impacts of sea level rise are increasing rapidly. Enhanced risk zones for sea level rise are specified for the Oxnard Plain of Ventura County on the south coast of California. Four separate sea level rise scenarios are considered: (1) low (sea level rise only); (2) moderate (adding erosion); (3) high (adding erosion and storm surges); and (4) a maximum case, a 3 m enhanced risk zone. Population impacts are outlined for the 3 m zone. More serious impacts from storm surges are expected than from sea level rise and erosion. Stakeholders who support or oppose policies which may expose populations to sea level rise include energy, commercial, financial, industrial, public agency, private interest and governmental organizations. These organizations respond to extreme events from differing positions. Vested interests determine the degree of mitigation employed by stakeholders to defer impacts of sea level rise.

  12. Analysis of sea level and sea surface temperature changes in the Black Sea

    NASA Astrophysics Data System (ADS)

    Betul Avsar, Nevin; Jin, Shuanggen; Kutoglu, Hakan; Erol, Bihter

    2016-07-01

    The Black Sea is a nearly closed sea with limited interaction with the Mediterranean Sea through the Turkish Straits. Measurement of sea level change will provide constraints on the water mass balance and thermal expansion of seawaters in response to climate change. In this paper, sea level changes in the Black Sea are investigated between January 1993 and December 2014 using multi-mission satellite altimetry data and sea surface temperature (SST) data. Here, the daily Maps of Sea Level Anomaly (MSLA) gridded with a 1/8°x1/8° spatial resolution from AVISO and the NOAA 1/4° daily Optimum Interpolation Sea Surface Temperature (OISST) Anomaly data set are used. The annual cycles of sea level and sea surface temperature changes reach the maximum values in November and January, respectively. The trend is 3.16±0.77 mm/yr for sea level change and -0.06±0.01°C/yr for sea surface temperature during the same 22-year period. The observed sea level rise is highly correlated with sea surface warming for the same time periods. In addition, the geographical distribution of the rates of the Black Sea level and SST changes between January 1993 and December 2014 are further analyzed, showing a good agreement in the eastern Black Sea. The rates of sea level rise and sea surface warming are larger in the eastern part than in the western part except in the northwestern Black Sea. Finally, the temporal correlation between sea level and SST time series are presented based on the Empirical Orthogonal Function (EOF) analysis.

  13. Wave transformation across coral reefs under changing sea levels

    NASA Astrophysics Data System (ADS)

    Harris, Daniel; Power, Hannah; Vila-Conejo, Ana; Webster, Jody

    2015-04-01

    The transformation of swell waves from deep water across reef flats is the primary process regulating energy regimes in coral reef systems. Coral reefs are effective barriers removing up to 99% of wave energy during breaking and propagation across reef flats. Consequently back-reef environments are often considered low energy with only limited sediment transport and geomorphic change during modal conditions. Coral reefs, and specifically reef flats, therefore provide important protection to tropical coastlines from coastal erosion and recession. However, changes in sea level could lead to significant changes in the dissipation of swell wave energy in coral reef systems with wave heights dependent on the depth over the reef flat. This suggests that a rise in sea level would also lead to significantly higher energy conditions exacerbating the transgressive effects of sea level rise on tropical beaches and reef islands. This study examines the potential implications of different sea level scenarios on the transformation of waves across the windward reef flats of One Tree Reef, southern Great Barrier Reef. Waves were measured on the reef flats and back-reef sand apron of One Tree Reef. A one-dimensional wave model was calibrated and used to investigate wave processes on the reef flats under different mean sea level (MSL) scenarios (present MSL, +1 m MSL, and +2 m MSL). These scenarios represent both potential future sea level states and also the paleo sea level of the late Holocene in the southern Great Barrier Reef. Wave heights were shown to increase under sea level rise, with greater wave induced orbital velocities affecting the bed under higher sea levels. In general waves were more likely to entrain and transport sediment both on the reef flat and in the back reef environment under higher sea levels which has implications for not only forecasted climate change scenarios but also for interpreting geological changes during the late Holocene when sea levels were 1

  14. Sea-level variability in the Mediterranean Sea from altimetry and tide gauges

    NASA Astrophysics Data System (ADS)

    Bonaduce, A.; Pinardi, N.; Oddo, P.; Spada, G.; Larnicol, G.

    2016-11-01

    Sea-level variability in the Mediterranean Sea was investigated by means of in-situ (tide-gauge) and satellite altimetry data over a period spanning two decades (from 1993 to 2012). The paper details the sea-level variations during this time period retrieved from the two data sets. Mean sea-level (MSL) estimates obtained from tide-gauge data showed root mean square differences (RMSDs) in the order of 40-50 % of the variance of the MSL signal estimated from satellite altimetry data, with a dependency on the number and quality of the in-situ data considered. Considering the individual time-series, the results showed that coastal tide-gauge and satellite sea-level signals are comparable, with RMSDs that range between 2.5 and 5 cm and correlation coefficients up to the order of 0.8. A coherence analysis and power spectra comparison showed that two signals have a very similar energetic content at semi-annual temporal scales and below, while a phase drift was observed at higher frequencies. Positive sea-level linear trends for the analysis period were estimated for both the mean sea-level and the coastal stations. From 1993 to 2012, the mean sea-level trend (2.44± 0.5 mm year^{-1}) was found to be affected by the positive anomalies of 2010 and 2011, which were observed in all the cases analysed and were mainly distributed in the eastern part of the basin. Ensemble empirical mode decomposition showed that these events were related to the processes that have dominant periodicities of ˜10 years, and positive residual sea-level trend were generally observed in both data-sets. In terms of mean sea-level trends, a significant positive sea-level trend (>95 %) in the Mediterranean Sea was found on the basis of at least 15 years of data.

  15. Sea-level variability in the Mediterranean Sea from altimetry and tide gauges

    NASA Astrophysics Data System (ADS)

    Bonaduce, Antonio; Pinardi, Nadia; Oddo, Paolo; Spada, Giorgio; Larnicol, Gilles

    2016-04-01

    Sea-level variability in the Mediterranean Sea was investigated by means of in-situ (tide-gauge) and satellite altimetry data over a period spanning two decades (from 1993 to 2012). The paper details the sea-level variations during this time period retrieved from the two data sets. Mean sea-level (MSL) estimates obtained from tide-gauge data showed root mean square differences (RMSDs) in the order of 40-50 % of the variance of the MSL signal estimated from satellite altimetry data, with a dependency on the number and quality of the in-situ data considered. Considering the individual time-series, the results showed that coastal tide-gauge and satellite sea-level signals are comparable, with RMSDs that range between 2.5 and 5 cm and correlation coefficients up to the order of 0.8. A coherence analysis and power spectra comparison showed that two signals have a very similar energetic content at semi-annual temporal scales and below, while a phase drift was observed at higher frequencies. Positive sea-level linear trends for the analysis period were estimated for both the mean sea-level and the coastal stations. From 1993 to 2012, the mean sea-level trend (2.44 ± 0.5 mm yr-1) was found to be affected by the positive anomalies of 2010 and 2011, which were observed in all the cases analysed and were mainly distributed in the eastern part of the basin. Ensemble Empirical Mode Decomposition (EEMD) showed that these events were related to the processes that have dominant periodicities of ˜10 years, and positive residual sea-level trend were generally observed in both data-sets. In terms of mean sea-level trends, a significant positive sea-level trend (> 95 %) in the Mediterranean Sea was found on the basis of at least 15 years of data.

  16. Future Extreme Sea Level Variability in the Tropical Pacific

    NASA Astrophysics Data System (ADS)

    Widlansky, M. J.; Timmermann, A.; Stuecker, M. F.; McGregor, S.; Cai, W.; Chikamoto, Y.

    2014-12-01

    During strong El Niño events, sea level drops around tropical western Pacific islands by up to 20-30 cm. Such extreme events (referred to in Samoa as 'taimasa') expose shallow reefs, thereby damaging associated coastal ecosystems and contributing to the formation of 'flat topped coral heads' often referred to as microatolls. We show that during the termination of strong El Niño events, a southward movement of weak trade winds prolongs extreme low sea levels in the southwestern Pacific. Whereas future sea levels are projected to gradually rise, recent modeling evidence suggests that the frequency of strong El Niño events (which alter local trade winds and sea level) is very likely to increase with greenhouse warming. Such changes could exacerbate El Niño-related sea level drops, especially in the tropical southwestern Pacific. Using present-generation coupled climate models forced with increasing greenhouse-gas concentrations, we assess how the interplay between global mean sea level rise, on one hand, and more frequent interannual sea level drops, on the other, will affect future coastal sea levels in the tropical Pacific.

  17. Future extreme sea level seesaws in the tropical Pacific.

    PubMed

    Widlansky, Matthew J; Timmermann, Axel; Cai, Wenju

    2015-09-01

    Global mean sea levels are projected to gradually rise in response to greenhouse warming. However, on shorter time scales, modes of natural climate variability in the Pacific, such as the El Niño-Southern Oscillation (ENSO), can affect regional sea level variability and extremes, with considerable impacts on coastal ecosystems and island nations. How these shorter-term sea level fluctuations will change in association with a projected increase in extreme El Niño and its atmospheric variability remains unknown. Using present-generation coupled climate models forced with increasing greenhouse gas concentrations and subtracting the effect of global mean sea level rise, we find that climate change will enhance El Niño-related sea level extremes, especially in the tropical southwestern Pacific, where very low sea level events, locally known as Taimasa, are projected to double in occurrence. Additionally, and throughout the tropical Pacific, prolonged interannual sea level inundations are also found to become more likely with greenhouse warming and increased frequency of extreme La Niña events, thus exacerbating the coastal impacts of the projected global mean sea level rise.

  18. Future extreme sea level seesaws in the tropical Pacific

    PubMed Central

    Widlansky, Matthew J.; Timmermann, Axel; Cai, Wenju

    2015-01-01

    Global mean sea levels are projected to gradually rise in response to greenhouse warming. However, on shorter time scales, modes of natural climate variability in the Pacific, such as the El Niño–Southern Oscillation (ENSO), can affect regional sea level variability and extremes, with considerable impacts on coastal ecosystems and island nations. How these shorter-term sea level fluctuations will change in association with a projected increase in extreme El Niño and its atmospheric variability remains unknown. Using present-generation coupled climate models forced with increasing greenhouse gas concentrations and subtracting the effect of global mean sea level rise, we find that climate change will enhance El Niño–related sea level extremes, especially in the tropical southwestern Pacific, where very low sea level events, locally known as Taimasa, are projected to double in occurrence. Additionally, and throughout the tropical Pacific, prolonged interannual sea level inundations are also found to become more likely with greenhouse warming and increased frequency of extreme La Niña events, thus exacerbating the coastal impacts of the projected global mean sea level rise. PMID:26601272

  19. How Does Climate Change Affect the Bering Sea Ecosystem?

    NASA Astrophysics Data System (ADS)

    Sigler, Michael F.; Harvey, H. Rodger; Ashjian, Carin J.; Lomas, Michael W.; Napp, Jeffrey M.; Stabeno, Phyllis J.; Van Pelt, Thomas I.

    2010-11-01

    The Bering Sea is one of the most productive marine ecosystems in the world, sustaining nearly half of U.S. annual commercial fish catches and providing food and cultural value to thousands of coastal and island residents. Fish and crab are abundant in the Bering Sea; whales, seals, and seabirds migrate there every year. In winter, the topography, latitude, atmosphere, and ocean circulation combine to produce a sea ice advance in the Bering Sea unmatched elsewhere in the Northern Hemisphere, and in spring the retreating ice; longer daylight hours; and nutrient-rich, deep-ocean waters forced up onto the broad continental shelf result in intense marine productivity (Figure 1). This seasonal ice cover is a major driver of Bering Sea ecology, making this ecosystem particularly sensitive to changes in climate. Predicted changes in ice cover in the coming decades have intensified concern about the future of this economically and culturally important region. In response, the North Pacific Research Board (NPRB) and the U.S. National Science Foundation (NSF) entered into a partnership in 2007 to support the Bering Sea Project, a comprehensive $52 million investigation to understand how climate change is affecting the Bering Sea ecosystem, ranging from lower trophic levels (e.g., plankton) to fish, seabirds, marine mammals, and, ultimately, humans. The project integrates two research programs, the NSF Bering Ecosystem Study (BEST) and the NPRB Bering Sea Integrated Ecosystem Research Program (BSIERP), with substantial in-kind contributions from the U.S. National Oceanic and Atmospheric Administration (NOAA) and the U.S. Fish and Wildlife Service.

  20. Long Term Sea Level Change in the Black Sea

    NASA Astrophysics Data System (ADS)

    Cokacar, Tulay; Emin, Özsoy

    2016-04-01

    Since 1992, altimeter missions have dramatically improved our knowledge and understanding of the oceans.This study investigates the long term sea level change during 1992-2015 in the Black Sea. The satellite altimeter data of the Topex-Poseidon, ERS-1 ands ERS-2 missions and sea level variations of 25 tide gauge stations and temperature/salinity data of 25 Argo float observed in the Black Sea are used for the analysis. The altimeter data are assessed and compared with the data from tide gauges and Argo floats in the Black Sea. First ARGO T/S profiles are used to assess the discrepancies observed between the altimeters. Then in situ measurements are compared with multiple altimeter data to detect in situ measurement anomalies and the corrections applied to improve the consistency of the data sets.

  1. Flooded! An Investigation of Sea-Level Rise in a Changing Climate

    ERIC Educational Resources Information Center

    Gillette, Brandon; Hamilton, Cheri

    2011-01-01

    Explore how melting ice sheets affect global sea levels. Sea-level rise (SLR) is a rise in the water level of the Earth's oceans. There are two major kinds of ice in the polar regions: sea ice and land ice. Land ice contributes to SLR and sea ice does not. This article explores the characteristics of sea ice and land ice and provides some hands-on…

  2. Sea level change: a philosophical approach

    NASA Astrophysics Data System (ADS)

    Leinfelder, R.; Seyfried, H.

    1993-07-01

    The present Cenozoic era is an ‘icehouse’ episode characterized by a low sea level. Since the beginning of the industrial revolution, the human race has been emitting greenhouse gases, increasing the global atmospheric temperature, and causing a rise in sea level. If emissions continue to increase at the present rate, average global temperatures may rise by 1.5°C by the year 2050, accompanied by a rise of about 30 cm in sea level. However, the prediction of future climatic conditions and sea level is hampered by the difficulty in modelling the interactions between the lithosphere, kryosphere, biosphere and atmosphere; in addition, the buffering capacity of our planet is still poorly understood. As scientists cannot offer unambiguous answers to simple questions, sorcerer's apprentices fill in the gaps, presenting plans to save planet without inconveniencing us. The geological record can help us to learn about the regulation mechanisms of our planet, many of which are connected with or expressed as sea level changes. Global changes in sea level are either tectono-eustatic or glacioeustatic. Plate tectonic processes strongly control sea levels and climate in the long term. There is a strong feed-back mechanism between sea level and climate; both can influence and determine each other. Although high sea levels are a powerful climatic buffer, falling sea levels accelerate climatic accentuation, the growth of the polar ice caps and will hence amplify the drop in sea level. Important sources of fossil greenhouse gases are botanic CO2 production, CO2 released by volcanic activity, and water vapour. The latter is particularly important when the surface area of the sea increases during a rise in sea level (‘maritime greenhouse effect’). A ‘volcanogenic greenhouse effect’ (release of volcanogenic CO2) is possibly not equally important, as intense volcanic activity may take place both during icehouse episodes as well as during greenhouse episodes. The hydrosphere

  3. Impact of global seismicity on sea level change assessment

    NASA Astrophysics Data System (ADS)

    Melini, D.; Piersanti, A.

    2006-03-01

    We analyze the effect of seismic activity on sea level variations by computing the time-dependent vertical crustal movement and geoid change due to coseismic deformations and postseismic relaxation effects. Seismic activity can affect both the absolute sea level, changing the Earth's gravity field and hence the geoid height, and the relative sea level (RSL), i.e., the radial distance between seafloor and geoid level. By using comprehensive seismic catalogs we assess the net effect of seismicity on tidal relative sea level measurements as well as on the global oceanic surfaces, and we obtain an estimate of absolute sea level variations of seismic origin. We modified the approach adopted in our previous analysis, considering the issue of water volume conservation by applying the sealevel equation, and we improved our computational methods, enabling us to evaluate the effect of an extremely large number of earthquakes on large grids covering the whole oceanic surface. These new potentialities allow us to perform more detailed investigations and to discover a quantitative explanation for the overall tendency of earthquakes to produce a positive global relative sea level variation. Our results confirm the finding of a previous analysis that on a global scale most of the signal is associated with a few giant thrust events and that RSL estimates obtained using tide gauge data can be sensibly affected by the seismically driven sea level signal. The recent measures of sea level obtained by satellite altimetry show a wide regional variation of sea level trends over the oceanic surface, with the largest deviations from the mean trend occurring in tectonically active regions. While our estimates of average absolute sea level variations turn out to be orders of magnitude smaller than the satellite-measured variations, we can still argue that the mass redistribution associated with aseismic tectonic processes may contribute to the observed regional variability of sea level

  4. Common Era Sea-Level Change

    NASA Astrophysics Data System (ADS)

    Horton, B.; Kemp, A.; Kopp, R. E., III

    2014-12-01

    The Atlantic coast of North America provides a sedimentary record of Common Era sea levels with the resolution to identify the mechanisms that cause spatial variability in sea-level rise. This coast has a small tidal range, improving the precision of sea-level reconstructions. Coastal subsidence (from glacial isostatic adjustment, GIA) creates accommodation space that is filled by salt-marsh peat and preserves accurate and precise sea-level indicators and abundant material for radiocarbon dating. In addition, the western North Atlantic Ocean is sensitive to spatial variability in sea-level change, because of static equilibrium effects from melting of the Greenland Ice Sheet, ocean circulation and wind-driven variability in the Gulf Stream and GIA induced land-level change from ongoing collapse of Laurentide forbuldge. We reveal three distinct patters in sea-level during the Common Era along the North American Atlantic coast, likely linked to wind-driven changes in the Gulf Stream: (1) Florida, sea level is essentially flat, with the record dominated by long-term geological processes; (2) North Carolina, sea level falls to a minimum near the beginning of the second millennium, climbing to an early Little Ice Age maximum in the fifteenth century, and then declining through most of the nineteenth century; and (3) New Jersey, a sea-level maximum around 900 CE, a sea-level minimum around 1500 CE, and a long-term sea-level rise through the second half of the second millennium. We combine the salt-marsh data from North American Atlantic coast with tide-gauge records and lower resolution proxies from the northern and southern hemispheres. We apply a noisy-input Gaussian process spatio-temporal modeling framework, which identifies a long-term falling global mean sea-level (GMSL), interrupted in the middle of the 19th century by an acceleration yielding a 20th century rate of rise extremely likely (probability P = 0:95) faster than any previous century in the Common Era.

  5. Sea-level rise and coastal wetlands.

    PubMed

    Blankespoor, Brian; Dasgupta, Susmita; Laplante, Benoit

    2014-12-01

    This paper seeks to quantify the impact of a1-m sea-level rise on coastal wetlands in 86 developing countries and territories. It is found that approximately 68 % of coastal wetlands in these countries are at risk. A large percentage of this estimated loss is found in Europe and Central Asia, East Asia, and the Pacific, as well as in the Middle East and North Africa. A small number of countries will be severely affected. China and Vietnam(in East Asia and the Pacific), Libya and Egypt (in the Middle East and North Africa), and Romania and Ukraine (in Europe and Central Asia) will bear most losses. In economic terms, the loss of coastal wetlands is likely to exceed $703 million per year in 2000 US dollars.

  6. Sea-Level Rise Impacts on Hudson River Marshes

    NASA Astrophysics Data System (ADS)

    Hooks, A.; Nitsche, F. O.

    2015-12-01

    The response of tidal marshes to increasing sea-level rise is uncertain. Tidal marshes can adapt to rising sea levels through vertical accretion and inland migration. Yet tidal marshes are vulnerable to submergence if the rate of sea-level rise exceeds the rate of accretion and if inland migration is limited by natural features or development. We studied how Piermont and Iona Island Marsh, two tidal marshes on the Hudson River, New York, would be affected by sea-level rise of 0.5m, 1m, and 1.5m by 2100. This study was based on the 2011-2012 Coastal New York LiDAR survey. Using GIS we mapped sea-level rise projections accounting for accretion rates and calculated the submerged area of the marsh. Based on the Hudson River National Estuarine Research Reserve Vegetation 2005 dataset, we studied how elevation zones based on vegetation distributions would change. To evaluate the potential for inland migration, we assessed land cover around each marsh using the National Land Cover Database 2011 Land Cover dataset and examined the slope beyond the marsh boundaries. With an accretion rate of 0.29cm/year and 0.5m of sea-level rise by 2100, Piermont Marsh would be mostly unchanged. With 1.5m of sea-level rise, 86% of Piermont Marsh would be flooded. For Iona Island Marsh with an accretion rate of 0.78cm/year, sea-level rise of 0.5m by 2100 would result in a 4% expansion while 1.5m sea-level rise would cause inundation of 17% of the marsh. The results indicate that Piermont and Iona Island Marsh may be able to survive rates of sea-level rise such as 0.5m by 2100 through vertical accretion. At rates of sea-level rise like 1.5m by 2100, vertical accretion cannot match sea-level rise, submerging parts of the marshes. High elevations and steep slopes limit Piermont and Iona Island Marsh's ability to migrate inland. Understanding the impacts of sea-level rise on Piermont and Iona Island Marsh allows for long-term planning and could motivate marsh conservation programs.

  7. A global reanalysis of storm surges and extreme sea levels

    NASA Astrophysics Data System (ADS)

    Muis, Sanne; Verlaan, Martin; Winsemius, Hessel C.; Aerts, Jeroen C. J. H.; Ward, Philip J.

    2016-06-01

    Extreme sea levels, caused by storm surges and high tides, can have devastating societal impacts. To effectively protect our coasts, global information on coastal flooding is needed. Here we present the first global reanalysis of storm surges and extreme sea levels (GTSR data set) based on hydrodynamic modelling. GTSR covers the entire world's coastline and consists of time series of tides and surges, and estimates of extreme sea levels. Validation shows that there is good agreement between modelled and observed sea levels, and that the performance of GTSR is similar to that of many regional hydrodynamic models. Due to the limited resolution of the meteorological forcing, extremes are slightly underestimated. This particularly affects tropical cyclones, which requires further research. We foresee applications in assessing flood risk and impacts of climate change. As a first application of GTSR, we estimate that 1.3% of the global population is exposed to a 1 in 100-year flood.

  8. A global reanalysis of storm surges and extreme sea levels

    PubMed Central

    Muis, Sanne; Verlaan, Martin; Winsemius, Hessel C.; Aerts, Jeroen C. J. H.; Ward, Philip J.

    2016-01-01

    Extreme sea levels, caused by storm surges and high tides, can have devastating societal impacts. To effectively protect our coasts, global information on coastal flooding is needed. Here we present the first global reanalysis of storm surges and extreme sea levels (GTSR data set) based on hydrodynamic modelling. GTSR covers the entire world's coastline and consists of time series of tides and surges, and estimates of extreme sea levels. Validation shows that there is good agreement between modelled and observed sea levels, and that the performance of GTSR is similar to that of many regional hydrodynamic models. Due to the limited resolution of the meteorological forcing, extremes are slightly underestimated. This particularly affects tropical cyclones, which requires further research. We foresee applications in assessing flood risk and impacts of climate change. As a first application of GTSR, we estimate that 1.3% of the global population is exposed to a 1 in 100-year flood. PMID:27346549

  9. Global sea level linked to global temperature

    PubMed Central

    Vermeer, Martin; Rahmstorf, Stefan

    2009-01-01

    We propose a simple relationship linking global sea-level variations on time scales of decades to centuries to global mean temperature. This relationship is tested on synthetic data from a global climate model for the past millennium and the next century. When applied to observed data of sea level and temperature for 1880–2000, and taking into account known anthropogenic hydrologic contributions to sea level, the correlation is >0.99, explaining 98% of the variance. For future global temperature scenarios of the Intergovernmental Panel on Climate Change's Fourth Assessment Report, the relationship projects a sea-level rise ranging from 75 to 190 cm for the period 1990–2100. PMID:19995972

  10. Climate Adaptation and Sea Level Rise

    EPA Pesticide Factsheets

    EPA supports the development and maintenance of water utility infrastructure across the country. Included in this effort is helping the nation’s water utilities anticipate, plan for, and adapt to risks from flooding, sea level rise, and storm surge.

  11. Annotated Bibliography of Relative Sea Level Change

    DTIC Science & Technology

    1991-09-01

    contribution, and--future sea-level scenarios. If an accelerated rise of sea level occurs as predicted, coastal communities will be faced with deciding the...Moreover, seismic sequence analysis in ne.. u.plo- ration areas allow for reliable predictions of geologic age ahead of drilli.g and facilitate...comparable age suggest a strong seaward tilt of the outer continental shelf. The outer -shelf over the Baltimore Canyon trough geosyncline has

  12. Future high sea levels in south Sweden

    SciTech Connect

    Blomgren, S.H.; Hanson, H.

    1997-12-31

    An estimation of future mean high water levels in Oeresund and the southwest Baltic Sea is presented together with a discussion of probable consequences for Falsterbo Peninsula, a trumpet-shaped sandy formation of some 25 km{sup 2} size situated in the very southwest corner of Sweden. A literature review coupled with sea-level measurements and observations made in the area every four hours since October 1945 are given and comprise the base for the present analysis.

  13. Precise mean sea level measurements using the Global Positioning System

    NASA Technical Reports Server (NTRS)

    Kelecy, Thomas M.; Born, George H.; Parke, Michael E.; Rocken, Christian

    1994-01-01

    This paper describes the results of a sea level measurement test conducted off La Jolla, California, in November of 1991. The purpose of this test was to determine accurate sea level measurements using a Global Positioning System (GPS) equipped buoy. These measurements were intended to be used as the sea level component for calibration of the ERS 1 satellite altimeter. Measurements were collected on November 25 and 28 when the ERS 1 satellite overflew the calibration area. Two different types of buoys were used. A waverider design was used on November 25 and a spar design on November 28. This provided the opportunity to examine how dynamic effects of the measurement platform might affect the sea level accuracy. The two buoys were deployed at locations approximately 1.2 km apart and about 15 km west of a reference GPS receiver located on the rooftop of the Institute of Geophysics and Planetary Physics at the Scripps Institute of Oceanography. GPS solutions were computed for 45 minutes on each day and used to produce two sea level time series. An estimate of the mean sea level at both locations was computed by subtracting tide gage data collected at the Scripps Pier from the GPS-determined sea level measurements and then filtering out the high-frequency components due to waves and buoy dynamics. In both cases the GPS estimate differed from Rapp's mean altimetric surface by 0.06 m. Thus, the gradient in the GPS measurements matched the gradient in Rapp's surface. These results suggest that accurate sea level can be determined using GPS on widely differing platforms as long as care is taken to determine the height of the GPS antenna phase center above water level. Application areas include measurement of absolute sea level, of temporal variations in sea level, and of sea level gradients (dominantly the geoid). Specific applications would include ocean altimeter calibration, monitoring of sea level in remote regions, and regional experiments requiring spatial and

  14. Glacier Contributions to Sea Level Rise

    NASA Astrophysics Data System (ADS)

    Gardner, A. S.; Cogley, J. G.; Moholdt, G.; Wouters, B.; Wiese, D. N.

    2015-12-01

    Global mean sea level is rising in response to two primary factors: warming oceans and diminishing glaciers and ice sheets. If melted completely, glaciers would raise sea levels by half a meter, much less than that the 80 meters or so that would result from total melt of the massive Greenland and Antarctic ice sheets. That is why glacier contributions to sea level rise have been less studied, allowing estimates of to vary widely. Glacier contributions to sea level change are challenging to quantify as they are broadly distributed, located in remote and poorly accessible high latitude and high altitude regions, and ground observations are sparse. Advances in satellite altimetry (ICESat) and gravimetry (GRACE) have helped, but they also have their own challenges and limitations. Here we present an updated (2003-2014) synthesis of multiple techniques adapted for varying regions to show that rates of glacier loss change little between the 2003-2009 and 2003-2014 periods, accounting for roughly one third of global mean sea level rise. Over the next century and beyond glaciers are expected to continue to contribute substantial volumes of water to the world's oceans, motivating continued study of how glaciers respond to climate change that will improve projections of future sea levels.

  15. Regional sea level change in the Thailand-Indonesia region

    NASA Astrophysics Data System (ADS)

    Fenoglio-Marc, L.; Becker, M. H.; Buchhaupt, C.

    2013-12-01

    It is expected that the regional sea level rise will strongly affect particular regions with direct impacts including submergence of coastal zones, rising water tables and salt intrusion into groundwaters. It can possibly also exacerbate other factors as floodings, associated to storms and hurricanes, as well as ground subsidence of anthropogenic nature. The Thailand-Vietnam-Indonesian region is one of those zones. On land, the Chao-Praya and Mekong Delta are fertile alluvial zones. The potential for sea level increases and extreme floodings due to global warming makes the Deltas a place where local, regional, and global environmental changes are converging. We investigate the relative roles of regional and global mechanisms resulting in multidecadal variations and inflections in the rate of sea level change. Altimetry and GRACE data are used to investigate the variation of land floodings. The land surface water extent is evaluated at 25 km sampling intervals over fifteen years (1993-2007) using a multisatellite methodology which captures the extent of episodic and seasonal inundations, wetlands, rivers, lakes, and irrigated agriculture, using passive and active (microwaves and visible observations. The regional sea level change is analysed during the period 1993-2012 using satellite altimetry, wind and ocean model data, tide gauge data and GPS. The rates of absolute eustatic sea level rise derived from satellite altimetry through 19-year long precise altimeter observations are in average higher than the global mean rate. Several tide gauge records indicate an even higher sea level rise relative to land. We show that the sea level change is closely linked to the ENSO mode of variability and strongly affected by changes in wind forcing and ocean circulation. We have determined the vertical crustal motion at a given tide gauge location by differencing the tide gauge sea level time-series with an equivalent time-series derived from satellite altimetry and by computing

  16. Development of the Bulgarian Sea Level Service

    NASA Astrophysics Data System (ADS)

    Palazov, Atanas

    2013-04-01

    Systematic sea level measurements have been started in Bulgaria in the beginning of 20th century and nowadays there are 16 coastal sea level stations in operation. Operators of sea level stations are: National Institute of Meteorology and Hydrology, Bulgarian Academy of Sciences (NIMH) - 6 stations, Cadastre Agency, Ministry of Regional Development and Public Works (CA) - 4 stations, Port Infrastructure (PI) - 5 stations and Institute of Oceanology, Bulgarian Academy of Sciences (IO-BAS) - 1 station. Six of them are able to provide real time data. The sea level observations in the network of NIMH, performed at six main Bulgarian ports using standard poles, started in 1910. The program, implemented on the NIMH stations, includes daily measurements of the sea level with water gauges (poles). The position of a zero mark of the water gauge is checked once per year. The sea level network of the CA consists of 4 stations: Varna and Burgas (operational since 1928), Irakly and Ahtopol (since 1971). These stations are equipped with stilling-well tide gauges and with mechanical writing devices which draws sea level changes on paper. A mechanical paper writing instruments were installed in Varna and Burgas during 1928 and in 1971, a new paper writing instruments of type SUM (Russian) were installed in the stations of Irakly and Ahtopol. A set of five sea level stations in the ports of Balchik, Varna west, Pomorie, Burgas and Oil port Burgas was build during 2009 in the frame of Port Operational Marine Observing System (POMOS), equipped with high accuracy microwave instruments and operated by PI. In 2010 a new sea level station was set up in the IO-BAS coastal research base Shkorpolovtci. The station is equipped with high accuracy microwave instrument. These six stations are providing real time data. According to the decision of the Council of Ministers in 2012 sea level stations in Varna, Irakly, Burgas and Ahtopol will be operated jointly by Bulgarian Academy of Sciences and

  17. Paleoshoreline record of relative Holocene sea levels on Pacific islands

    NASA Astrophysics Data System (ADS)

    Dickinson, William R.

    2001-11-01

    Understanding the history of relative Holocene sea levels on Pacific islands is important for constraining fundamental geodynamic theories, interpreting the environments of early human occupation sites, and forecasting future environmental conditions on the islands. An observational paleoshoreline record is provided by emergent paleoshoreline indicators formed at higher relative sea levels, hence standing at higher elevations than modern counterparts. Emergent paleoshoreline notches in limestone seacliffs record paleo-high-tide levels and emergent paleoreef flats record paleo-low-tide levels, whereas emergent paleobeachrock locally records paleo-intertidal levels. Both paleonotches and paleoreefs occur along the coasts of high-standing islands exposing volcanic bedrock and uplifted reef complexes, but low-lying coralline atolls lack sufficient relief to preserve paleonotches. Controls on relative Holocene sea level include global eustatic and regional hydro-isostatic changes in ambient sea level relative to island landmasses, and shifts in the elevations of islands relative to sea level caused by thermal subsidence of the oceanic lithosphere or thermally rejuvenated loci of hotspot volcanism, by flexure of the lithosphere under the load of growing volcanic edifices (Hawaii, Samoa, Society Islands), by arching of the lithosphere over trench forebulges (Loyalty Islands, Niue, Bellona-Rennell), and by tectonism within forearc belts between active volcanic chains and trenches (Mariana Islands, Tonga, Vanuatu). The dominant pattern of relative sea-level change, where not overprinted by local tectonism or lithospheric flexure, was a uniform early Holocene rise in eustatic sea level followed by a regionally variable late Holocene hydro-isostatic drawdown in sea level. The resultant was a mid-Holocene highstand in relative sea level that affected the development of shoreline morphology throughout the tropical Pacific Ocean. The earliest human migrations into intra

  18. Tritium level along Romanian Black Sea Coast

    SciTech Connect

    Varlam, C.; Stefanescu, I.; Popescu, I.; Faurescu, I.

    2008-07-15

    Establishing the tritium level along the Romanian Black Sea Coast, after 10 years of exploitation of the nuclear power plant from Cernavoda, is a first step in evaluating its impact on the Black Sea ecosystem. The monitoring program consists of tritium activity concentration measurement in sea water and precipitation from Black Sea Coast between April 2005 and April 2006. The sampling points were spread over the Danube-Black Sea Canal - before the locks Agigea and Navodari, and Black Sea along the coast to the Bulgarian border. The average tritium concentration in sea water collected from the sampling locations had the value of 11.1 {+-} 2.1 TU, close to tritium concentration in precipitation. Although an operating nuclear power plant exists in the monitored area, the values of tritium concentration in two locations are slightly higher than those recorded elsewhere. To conclude, it could be emphasized that until now, Cernavoda NPP did not had any influence on the tritium concentration of the Black Sea Shore. (authors)

  19. The importance of sea-level research (Plinius Medal Lecture)

    NASA Astrophysics Data System (ADS)

    Horton, Benjamin

    2016-04-01

    200 million people worldwide live in coastal regions less than 5 meters above sea level. By the end of the 21st century, this figure is estimated to increase to 500 million. These low-lying coastal regions are vulnerable to changes in sea level brought about by climate change, storms or earthquakes. But the historic and instrumental record is too short to fully understand the climate relationships and capture the occurrence of the rare, but most destructive events. The coastal sedimentary record provides a long-term and robust paleo perspective on the rates, magnitudes and spatial variability of sea-level rise and the frequency (recurrence interval) and magnitude of destructive events. Reconstructions of paleo sea level are important for identifying the meltwater contributions, constraining parameters in Earth-Ice models, and estimating past and present rates of spatially variable sea-level change associated glacial isostatic adjustment, sediment compaction and tidal range variability. Sea-level reconstructions capture multiple phases of climate and sea-level behavior for model calibration and provide a pre-anthropogenic background against which to compare recent trends. Pre-historic earthquakes (Mw>8.0) are often associated with abrupt and cyclical patterns of vertical land-motion that are manifest in coastal sedimentary archives as abrupt changes in relative sea level. Geologic evidence of paleoearthquakes elucidates characteristic and repeated pattern of land-level movements associated with the earthquake-deformation cycle. Tsunamis and storms leave behind anomalous and characteristic sediment that is incorporated into the coastal sedimentary record often as evidence of a high-energy event affecting a low-energy, depositional environment. Records of tsunamis developed from the sedimentary deposits they leave behind improve understanding of tsunami processes and frequency by expanding the age range of events available for study. Reconstructions of paleo storms

  20. Sea Level Rise Impacts On Infrastructure Vulnerability

    NASA Astrophysics Data System (ADS)

    Pasqualini, D.; Mccown, A. W.; Backhaus, S.; Urban, N. M.

    2015-12-01

    Increase of global sea level is one of the potential consequences of climate change and represents a threat for the U.S.A coastal regions, which are highly populated and home of critical infrastructures. The potential danger caused by sea level rise may escalate if sea level rise is coupled with an increase in frequency and intensity of storms that may strike these regions. These coupled threats present a clear risk to population and critical infrastructure and are concerns for Federal, State, and particularly local response and recovery planners. Understanding the effect of sea level rise on the risk to critical infrastructure is crucial for long planning and for mitigating potential damages. In this work we quantify how infrastructure vulnerability to a range of storms changes due to an increase of sea level. Our study focuses on the Norfolk area of the U.S.A. We assess the direct damage of drinking water and wastewater facilities and the power sector caused by a distribution of synthetic hurricanes. In addition, our analysis estimates indirect consequences of these damages on population and economic activities accounting also for interdependencies across infrastructures. While projections unanimously indicate an increase in the rate of sea level rise, the scientific community does not agree on the size of this rate. Our risk assessment accounts for this uncertainty simulating a distribution of sea level rise for a specific climate scenario. Using our impact assessment results and assuming an increase of future hurricanes frequencies and intensities, we also estimate the expected benefits for critical infrastructure.

  1. Solution notches, earthquakes, and sea level, Haiti

    NASA Astrophysics Data System (ADS)

    Schiffman, C. R.; Mildor, B. S.; Bilham, R. G.

    2010-12-01

    Shortly after the 12 January 2010 Haiti earthquake, we installed an array of five tide gauges to determine sea level and its variability in the region of uplifted corals on the coast SW of Leogane, Haiti, that had been uplift ≤30 cm during the earthquake. Each gauge consists of a pressure transducer bolted 50-80 cm below mean sea level, which samples the difference between atmospheric pressure and sea pressure every 10 minutes. The data are transmitted via the Iridium satellite and are publically available with a latency of 10 minutes to 2 hours. The measurements reveal a maximum tidal range of ≈50 cm with 2-4 week oscillations in mean sea level of several cm. Sea slope, revealed by differences between adjacent gauges, varies 2-5 cm per 10 km at periods of 2-5 weeks, which imposes a disappointing limit to the utility of the gauges in estimating post seismic vertical motions. A parallel study of the form and elevation of coastal notches and mushroom rocks (rocks notched on all sides, hence forming a mushroom shape), along the coast west of Petit Goave suggests that these notches may provide an uplift history of the region over the past several hundreds of years. Notch sections in two areas were contoured, digitized, and compared to mean sea level. The notches mimic the histogram of sea level, suggesting that they are formed by dissolution by acidic surface waters. Notches formed two distinct levels, one approximately 58 cm above mean sea level, and the other approximately 157 cm above mean sea level. Several landslide blocks fell into the sea during the 2010 earthquake, and we anticipate these are destined for conversion to future mushroom rocks. Surfaces have been prepared on these blocks to study the rate of notch formation in situ, and samples are being subjected to acid corrosion in laboratory conditions, with the hope that the depth of notches may provide an estimate of the time of fall of previous rocks to help constrain the earthquake history of this area

  2. Future sea-level rise in the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Galassi, Gaia; Spada, Giorgio

    2014-05-01

    Secular sea level variations in the Mediterranean Sea are the result of a number of processes characterized by distinct time scales and spatial patterns. Here we predict the future sea level variations in the Mediterranean Sea to year 2050 combining the contributions from terrestrial ice melt (TIM), glacial isostatic adjustment (GIA), and the ocean response (OR) that includes the thermal expansion and the ocean circulation contributions. The three contributions are characterized by comparable magnitudes but distinctly different sea-level fingerprints across the Mediterranean basin. The TIM component of future sea-level rise is taken from Spada et al. (2013) and it is mainly driven by the melt of small glaciers and ice caps and by the dynamic ice loss from Antarctica. The sea-level fingerprint associated with GIA is studied using two distinct models available from the literature: ICE-5G(VM2) (Peltier, 2004) and the ice model progressively developed at the Research School of Earth Sciences (RSES) of the National Australian University (KL05) (see Fleming and Lambeck, 2004 and references therein). Both the GIA and the TIM sea-level predictions have been obtained with the aid of the SELEN program (Spada and Stocchi, 2007). The spatially-averaged OR component, which includes thermosteric and halosteric sea-level variations, recently obtained using a regional coupled ocean-atmosphere model (Carillo et al., 2012), vary between 2 and 7 cm according to scenarios adopted (EA1B and EA1B2, see Meehl at al., 2007). Since the sea-level variations associated with TIM mainly result from the gravitational interactions between the cryosphere components, the oceans and the solid Earth, and long-wavelength rotational variations, they are characterized by a very smooth global pattern and by a marked zonal symmetry reflecting the dipole geometry of the ice sources. Since the Mediterranean Sea is located in the intermediate far-field of major ice sources, TIM sea-level changes have sub

  3. Terrestrial Waters and Sea Level Variations on Interannual Time Scale

    NASA Technical Reports Server (NTRS)

    Llovel, W.; Becker, M.; Cazenave, A.; Jevrejeva, S.; Alkama, R.; Decharme, B.; Douville, H.; Ablain, M.; Beckley, B.

    2011-01-01

    On decadal to multi-decadal time scales, thermal expansion of sea waters and land ice loss are the main contributors to sea level variations. However, modification of the terrestrial water cycle due to climate variability and direct anthropogenic forcing may also affect sea level. For the past decades, variations in land water storage and corresponding effects on sea level cannot be directly estimated from observations because these are almost non-existent at global continental scale. However, global hydrological models developed for atmospheric and climatic studies can be used for estimating total water storage. For the recent years (since mid-2002), terrestrial water storage change can be directly estimated from observations of the GRACE space gravimetry mission. In this study, we analyse the interannual variability of total land water storage, and investigate its contribution to mean sea level variability at interannual time scale. We consider three different periods that, each, depend on data availability: (1) GRACE era (2003-2009), (2) 1993-2003 and (3) 1955-1995. For the GRACE era (period 1), change in land water storage is estimated using different GRACE products over the 33 largest river basins worldwide. For periods 2 and 3, we use outputs from the ISBA-TRIP (Interactions between Soil, Biosphere, and Atmosphere-Total Runoff Integrating Pathways) global hydrological model. For each time span, we compare change in land water storage (expressed in sea level equivalent) to observed mean sea level, either from satellite altimetry (periods 1 and 2) or tide gauge records (period 3). For each data set and each time span, a trend has been removed as we focus on the interannual variability. We show that whatever the period considered, interannual variability of the mean sea level is essentially explained by interannual fluctuations in land water storage, with the largest contributions arising from tropical river basins.

  4. Upper Limit for Regional Sea Level Projections

    NASA Astrophysics Data System (ADS)

    Jevrejeva, Svetlana; Jackson, Luke; Riva, Riccardo; Grinsted, Aslak; Moore, John

    2016-04-01

    With more than 150 million people living within 1 m of high tide future sea level rise is one of the most damaging aspects of warming climate. The latest Intergovernmental Panel on Climate Change report (AR5 IPCC) noted that a 0.5 m rise in mean sea level will result in a dramatic increase the frequency of high water extremes - by an order of magnitude, or more in some regions. Thus the flood threat to the rapidly growing urban populations and associated infrastructure in coastal areas are major concerns for society. Hence, impact assessment, risk management, adaptation strategy and long-term decision making in coastal areas depend on projections of mean sea level and crucially its low probability, high impact, upper range. With probabilistic approach we produce regional sea level projections taking into account large uncertainties associated with Greenland and Antarctica ice sheets contribution. We calculate the upper limit (as 95%) for regional sea level projections by 2100 with RCP8.5 scenario, suggesting that for the most coastlines upper limit will exceed the global upper limit of 1.8 m.

  5. 3000 Years of Sea Level Change.

    NASA Astrophysics Data System (ADS)

    Tanner, William F.

    1992-03-01

    Sea level change is generally taken to indicate climate change, and may be more nearly global than what we perceive to be climate change. Close to the beach, even a small sea level change (such as 1-3 m) produces important changes in local depositional conditions. This effect can be deduced from a study of properly selected beach deposits.Various measures of beach-sand grain size indicate conditions of deposition. The best of these parameters is the kurtosis; it is a reliable indicator of surf-zone wave energy density. An abrupt energy-level shift, after centuries with little change, indicates sea level rise or drop. Kurtosis, within stated limits, shows this.Beach ridge systems (successive, distinct old beach deposits) span the last several thousand years. A sequence of sand samples across such a deposit provides grain-size evidence for alternating high and low sea level. Changes were 1 to 3 m vertically, and took place at rates of about 1 ern yr1. There were at least seven such events in the last 3000 years.The two most recent changes were the drop and subsequent rise that marked the Little Ice Age (starting about 1200 A.D.). One cannot say, from these data, that the planet has come fully out of the Little ice Age. Predictions about what sea level will do in the near future should be based on the many small changes (1 to 3 m) in the last few thousand years, rather than on the arbitrary, fictitious, and unrealistic absolute sea level that appears to underlie various popular forecasts.

  6. Extended Late Pleistocene Sea Level Record

    NASA Astrophysics Data System (ADS)

    Fairbanks, R. G.; Cao, L.; Mortlock, R. A.

    2006-12-01

    Several hundred new closed system 230Th/234U and radiocarbon dates and the addition of more cores and coral samples from the islands of Barbados, Kiritimati and Araki contribute to an enhanced sea level record for the late Pleistocene ranging from the present to 240,000 yrs BP. Application of more rigorous sample screening criteria, including redundant 231Pa/235U dates have resulted in more closed system ages and better sea level resolution. In addition, a multibeam survey has mapped an extensive glacial lowstand reef on a ridge south of Barbados that is capped by a set of pinnacle reefs that grew during the early deglaciation. Among our new observations, the more detailed Barbados sea level record now resolves a Younger Dryas still- stand and a sea level drop between 16,140 and 14,690, overlapping the timing of H1 by some age estimates. The coral ages bracketing melt water pulse 1A have been further refined to 14,082 +/- 28 yrs BP and 13,632 +/- 32 yrs BP (2-sigma). The Isotope Stage 3 interstadial ended with sea level near 87.5 meters below present at 29,500 years ago before dropping to full glacial levels. The last glacial sea level lowstand began as early as 26,000 yrs BP. Extensive dating of Marine Isotope Stage 3 interstadial reefs on the islands of Araki and Barbados have added considerable resolution to this time interval and reliably bracket lowstand intervals separating the interstadials. A new diagenesis model has improved our prospecting success for closed system ages from older reefs and added some critical dates to the sparse closed-system data set for MIS-5 and MIS-7 high stand reefs..

  7. Sea Level Rise in Santa Clara County

    NASA Technical Reports Server (NTRS)

    Milesi, Cristina

    2005-01-01

    Presentation by Cristina Milesi, First Author, NASA Ames Research Center, Moffett Field, CA at the "Meeting the Challenge of Sea Level Rise in Santa Clara County" on June 19, 2005 Santa Clara County, bordering with the southern portion of the San Francisco Bay, is highly vulnerable to flooding and to sea level rise (SLR). In this presentation, the latest sea level rise projections for the San Francisco Bay will be discussed in the context of extreme water height frequency and extent of flooding vulnerability. I will also present preliminary estimations of levee requirements and possible mitigation through tidal restoration of existing salt ponds. The examples will draw mainly from the work done by the NASA Climate Adaptation Science Investigators at NASA Ames.

  8. The Sea Level Fingerprints of Global Change

    NASA Astrophysics Data System (ADS)

    Mitrovica, J. X.; Hay, C.; Kopp, R. E., III; Morrow, E.

    2014-12-01

    It may be difficult to persuade those living in northern Europe that the sea level changes that their coastal communities face depends less on the total melting of polar ice sheets and glaciers than on the individual contributions to this total. In particular, melting of a specific ice sheet or mountain glacier drives deformational, gravitational and rotational perturbations to the Earth system that are manifest in a unique geometry, or fingerprint, of global sea level change. For example, melting from the Greenland Ice Sheet equivalent to 1 mm/yr of global mean sea level (GMSL) rise will lead to sea level rise of ~0 mm/yr in Dublin, ~0.2 mm/yr in Amsterdam, ~0.4 mm/yr in Boston and ~1.2 mm/yr in Cape Town. In contrast, if the same volume of ice melted from the West Antarctic Ice Sheet, all of the above sites would experience a sea level rise in the range 1.1-1.2 mm/yr. These fingerprints of modern ice melting, together with ocean thermal expansion and dynamic effects, and the ongoing signal from glacial isostatic adjustment in response to the last ice age, combine to produce a sea level field with significant geographic variability. In this talk I will highlight an analysis of global tide gauge records that takes full advantage of this variability to estimate both GMSL and the sources of meltwater over the last century, and to project GMSL to the end of the current century.

  9. Superstatistical analysis of sea-level fluctuations

    NASA Astrophysics Data System (ADS)

    Rabassa, Pau; Beck, Christian

    2015-01-01

    We perform a statistical analysis of measured time series of sea levels at various coastal locations in the UK, measured at time differences of 15 min over the past 20 years. When the astronomical tide and other deterministic components are removed from the record, a stochastic signal corresponding to the meteorological component remains, and this is well-described by a superstatistical model. We do various tests on the measured time series, and compare the data at 5 different UK locations. Overall the χ2-superstatistics is best suitable to describe the data, in particular when one looks at the dynamics of sea-level differences on short time scales.

  10. Monthly variations of the Caspian sea level and solar activity.

    NASA Astrophysics Data System (ADS)

    Romanchuk, P. R.; Pasechnik, M. N.

    The connection between 11-year cycle of solar activity and the Caspian sea level is investigated. Seasonal changes of the Caspian sea level and annual variations of the sea level with variations of solar activity are studied. The results of the verifications of the sea level forecasts obtained with application of the rules discovered by the authors are given.

  11. Sea Anemone Toxins Affecting Potassium Channels

    NASA Astrophysics Data System (ADS)

    Diochot, Sylvie; Lazdunski, Michel

    The great diversity of K+ channels and their wide distribution in many tissues are associated with important functions in cardiac and neuronal excitability that are now better understood thanks to the discovery of animal toxins. During the past few decades, sea anemones have provided a variety of toxins acting on voltage-sensitive sodium and, more recently, potassium channels. Currently there are three major structural groups of sea anemone K+ channel (SAK) toxins that have been characterized. Radioligand binding and electrophysiological experiments revealed that each group contains peptides displaying selective activities for different subfamilies of K+ channels. Short (35-37 amino acids) peptides in the group I display pore blocking effects on Kv1 channels. Molecular interactions of SAK-I toxins, important for activity and binding on Kv1 channels, implicate a spot of three conserved amino acid residues (Ser, Lys, Tyr) surrounded by other less conserved residues. Long (58-59 amino acids) SAK-II peptides display both enzymatic and K+ channel inhibitory activities. Medium size (42-43 amino acid) SAK-III peptides are gating modifiers which interact either with cardiac HERG or Kv3 channels by altering their voltage-dependent properties. SAK-III toxins bind to the S3C region in the outer vestibule of Kv channels. Sea anemones have proven to be a rich source of pharmacological tools, and some of the SAK toxins are now useful drugs for the diagnosis and treatment of autoimmune diseases.

  12. Impact of global seismicity on sea level changes assessment

    NASA Astrophysics Data System (ADS)

    Piersanti, A.; Melini, D.

    2006-12-01

    Seismic events alter the equilibrium state of the solid Earth and perturbate its gravitational field. Consequently, they are also likely to produce sea level variations. The perturbation of the Earth's gravity field due to internal mass redistribution following a seismic event affects the geoid and it is therefore responsible for a variation in the absolute sea level. The vertical deformation of the seafloor, together with the geoid change, produces also a relative sea level change. Here we quantify the contribution of last century global seismic activity to sealevel addressing also the problem of ocean volume conservation and discussing the physical reasons for the particular pattern of rise and fall. Our results show that, though small, the seismic induced signal on relative sealevel is not negligible also on global scale and that, in several extended oceanic regions, it could give an important contribution to the total detected trend.

  13. Sudden change: Climate and sea level

    SciTech Connect

    Tanner, W.F.

    1995-10-01

    Dates, magnitudes and rates of Holocene sea-level changes were reviewed at the 1995 meeting of the American Association for the Advancement of Science. Richard B. Alley (Penn. State U.) described laminae in Greenland ice cores, with details at the annual level. A major event of unknown nature occurred at roughly 8,000 B.P. Gerard Bond (Lamont-Doherty Observ., N.Y.) described sediment cores from the North Atlantic, with a major event at 8,000 B.P. Published work of K.S. Petersen (Danish Geol. Survey) from a well near Vust (Denmark) was reviewed: A rapid sea level rise (25 m), then a similar drop centered at 8,000 B.P. at 8-15 cm/yr. W.F. Tanner (Florida State U.) described the beach ridge plain in northern Denmark, where a sequence of more than 270 Holocene ridges shows the date of the big Mid-Holocene sea level change couplet, 8,000 B.P., with a magnitude of {open_quotes}more than 14 m,{close_quotes} plus smaller changes. These data showed vertical magnitudes of the larger sea level events (except the Mid-Holocene catastrophe) in the range of 1-to-5 meters. W.C. Parker (Florida State) sought possible cycles in the same sequence, but they were too poorly defined for detailed forecasts. Charles R. Bentley (U. of Wisconsin) examined the possibility of an early collapse of the West Antarctic marine ice sheet, with a sea level rise of about 5 meters, but concluded that it is unlikely.

  14. Sea Grant Education at the University Level.

    ERIC Educational Resources Information Center

    Fiske, Shirley J.

    1998-01-01

    Sea Grant's investment in university-level education shows a diversity of avenues for supporting students from experience-based internships, merit scholarships, and fellowships to team-based multidisciplinary undergraduate education. Describes such programs as Undergraduate Research Opportunities in ocean engineering, graduate research…

  15. Sea Level Rise National Coastal Property Model

    EPA Science Inventory

    The impact of sea level rise on coastal properties depends critically on the human response to the threat, which in turn depends on several factors, including the immediacy of the risk, the magnitude of property value at risk, options for adapting to the threat and the cost of th...

  16. Sea-Level Changes during the Tertiary.

    ERIC Educational Resources Information Center

    Vail, Peter R.; Hardenbol, Jan

    1979-01-01

    Discussed are research procedures undertaken to determine the magnitude and timing of eustatic sea-level changes during the Tertiary Period. Data now becoming available give scientists a knowledge of conditions that may have been conducive to the formation of petroleum. (BT)

  17. Late Cretaceous sea level from a paleoshoreline

    SciTech Connect

    McDonough, K.J.; Cross, T.A. )

    1991-04-10

    The contemporary elevation of a Late Cenomanian ({approx}93 Ma) shoreline was determined at five localities along the tectonically stable, eastern margin of the Cretaceous Western Interior Seaway, North America. This shoreline, represented by marine-to-nonmarine facies transitions in strata of the Greenhorn sequence (UZA-2 cycle of Haq et al. (1987)), was identified from outcrop and borehole data. Biostratigraphic zonations constrained the geologic age at each locality. Sequence stratigraphic correlations, based on identifying discrete progradational units and the surfaces that separate them, were used to refine age correlations to better than 100 kyr between localities. A single Cenomanian shoreline was correlated within a single progradational unit, and its elevation was determined at five localities. This paleostrandline occurs 265-286m above present-day sea level, at an average elevation of 276 m. Isostatic and flexural corrections were applied to remove the effects of postdepositional vertical movement, including sediment compaction by loading, uplift due to erosion, and glacial loading and rebound. Errors inherent in each measurement and each correction were estimated. Corrections and their cumulative error estimates yield a Late Cenomanian elevation of 269{plus minus}87 m above present sea level. The corrected elevation approximates sea level at 93 Ma and provides a measure of Late Cenomanian eustasy prior to the Early Turonian highstand. Establishing the absolute value for eustasy at a single point in geologic time provides a frame of reference for calibrating relative sea level curves, as well as constraining the magnitudes of tectonic subsidence, sediment flux, and other variables that controlled water depth and relative sea level.

  18. Benchmarking and testing the "Sea Level Equation

    NASA Astrophysics Data System (ADS)

    Spada, G.; Barletta, V. R.; Klemann, V.; van der Wal, W.; James, T. S.; Simon, K.; Riva, R. E. M.; Martinec, Z.; Gasperini, P.; Lund, B.; Wolf, D.; Vermeersen, L. L. A.; King, M. A.

    2012-04-01

    The study of the process of Glacial Isostatic Adjustment (GIA) and of the consequent sea level variations is gaining an increasingly important role within the geophysical community. Understanding the response of the Earth to the waxing and waning ice sheets is crucial in various contexts, ranging from the interpretation of modern satellite geodetic measurements to the projections of future sea level trends in response to climate change. All the processes accompanying GIA can be described solving the so-called Sea Level Equation (SLE), an integral equation that accounts for the interactions between the ice sheets, the solid Earth, and the oceans. Modern approaches to the SLE are based on various techniques that range from purely analytical formulations to fully numerical methods. Despite various teams independently investigating GIA, we do not have a suitably large set of agreed numerical results through which the methods may be validated. Following the example of the mantle convection community and our recent successful Benchmark for Post Glacial Rebound codes (Spada et al., 2011, doi: 10.1111/j.1365-246X.2011.04952.x), here we present the results of a benchmark study of independently developed codes designed to solve the SLE. This study has taken place within a collaboration facilitated through the European Cooperation in Science and Technology (COST) Action ES0701. The tests involve predictions of past and current sea level variations, and 3D deformations of the Earth surface. In spite of the signi?cant differences in the numerical methods employed, the test computations performed so far show a satisfactory agreement between the results provided by the participants. The differences found, which can be often attributed to the different numerical algorithms employed within the community, help to constrain the intrinsic errors in model predictions. These are of fundamental importance for a correct interpretation of the geodetic variations observed today, and

  19. A NOAA/NOS Sea Level Advisory

    NASA Astrophysics Data System (ADS)

    Sweet, W.

    2011-12-01

    In order for coastal communities to realize current impacts and become resilient to future changes, sea level advisories/bulletins are necessary that systematically monitor and document non-tidal anomalies (residuals) and flood-watch (elevation) conditions. The need became apparent after an exceptional sea level anomaly along the U.S. East Coast in June - July of 2009 when higher than normal sea levels coincided with a perigean-spring tide and flooded many coastal regions. The event spurred numerous public inquiries to the National Oceanic and Atmospheric Administration's (NOAA) Center for Operational Oceanographic Products and Services (CO-OPS) from coastal communities concerned because of the lack of any coastal storm signatures normally associated with such an anomaly. A subsequent NOAA report provided insight into some of the mechanisms involved in the event and methods for tracking their reoccurrences. NOAA/CO-OPS is the U.S. authority responsible for defining sea level datums and tracking their relative changes in support of marine navigation and national and state land-use boundaries. These efforts are supported by the National Water Level Observation Network (NWLON), whose long-term and widespread observations largely define a total water level measurement impacting a coastal community. NWLON time series provide estimates of local relative sea level trends, a product increasingly utilized by various stakeholders planning for the future. NWLON data also capture significant short-term changes and conveyance of high-water variations (from surge to seasonal scale) provides invaluable insight into inundation patterns ultimately needed for a more comprehensive planning guide. A NOAA/CO-OPS Sea Level Advisory Project will enhance high-water monitoring capabilities by: - Automatically detecting sea level anomalies and flood-watch occurrences - Seasonally calibrating the anomaly thresholds to a locality in terms of flood potential - Alerting for near

  20. The future for the Global Sea Level Observing System (GLOSS) Sea Level Data Rescue

    NASA Astrophysics Data System (ADS)

    Bradshaw, Elizabeth; Matthews, Andrew; Rickards, Lesley; Aarup, Thorkild

    2016-04-01

    Historical sea level data are rare and unrepeatable measurements with a number of applications in climate studies (sea level rise), oceanography (ocean currents, tides, surges), geodesy (national datum), geophysics and geology (coastal land movements) and other disciplines. However, long-term time series are concentrated in the northern hemisphere and there are no records at the Permanent Service for Mean Sea Level (PSMSL) global data bank longer than 100 years in the Arctic, Africa, South America or Antarctica. Data archaeology activities will help fill in the gaps in the global dataset and improve global sea level reconstruction. The Global Sea Level Observing System (GLOSS) is an international programme conducted under the auspices of the WMO-IOC Joint Technical Commission for Oceanography and Marine Meteorology. It was set up in 1985 to collect long-term tide gauge observations and to develop systems and standards "for ocean monitoring and flood warning purposes". At the GLOSS-GE-XIV Meeting in 2015, GLOSS agreed on a number of action items to be developed in the next two years. These were: 1. To explore mareogram digitisation applications, including NUNIEAU (more information available at: http://www.mediterranee.cerema.fr/logiciel-de-numerisation-des-enregistrements-r57.html) and other recent developments in scanning/digitisation software, such as IEDRO's Weather Wizards program, to see if they could be used via a browser. 2. To publicise sea level data archaeology and rescue by: • maintaining and regularly updating the Sea Level Data Archaeology page on the GLOSS website • strengthening links to the GLOSS data centres and data rescue organisations e.g. linking to IEDRO, ACRE, RDA • restarting the sea level data rescue blog with monthly posts. 3. Investigate sources of funding for data archaeology and rescue projects. 4. Propose "Guidelines" for rescuing sea level data. These action items will aid the discovery, scanning, digitising and quality control

  1. Speleothem evidence for MIS 5c and 5a sea level above modern level at Bermuda

    NASA Astrophysics Data System (ADS)

    Wainer, Karine A. I.; Rowe, Mark P.; Thomas, Alexander L.; Mason, Andrew J.; Williams, Bruce; Tamisiea, Mark E.; Williams, Felicity H.; Düsterhus, André; Henderson, Gideon M.

    2017-01-01

    The history of sea level in regions impacted by glacio-isostasy provides constraints on past ice-sheet distribution and on the characteristics of deformation of the planet in response to loading. The Western North Atlantic-Caribbean region, and Bermuda in particular, is strongly affected by the glacial forebulge that forms as a result of the Laurentide ice-sheet present during glacial periods. The timing of growth of speleothems, at elevations close to sea level can provide records of minimum relative sea level (RSL). In this study we used U-Th dating to precisely date growth periods of speleothems from Bermuda which were found close to modern-day sea level. Results suggest that RSL at this location was above modern during MIS5e, MIS5c and MIS5a. These data support controversial previous indications that Bermudian RSL was significantly higher than RSL at other locations during MIS 5c and MIS 5a. We confirm that it is possible to explain a wide range of MIS5c-a relative sea levels observed across the Western North Atlantic-Caribbean in glacial isostatic adjustment models, but only with a limited range of mantle deformation constants. This study demonstrates the particular power of Bermuda as a gauge for response of the forebulge to glacial loading, and demonstrates the potential for highstands at this location to be significantly higher than in other regions, helping to explain the high sea levels observed for Bermuda from earlier highstands.

  2. May organic pollutants affect fish populations in the North Sea?

    PubMed

    Hylland, Ketil; Beyer, Jonny; Berntssen, Marc; Klungsøyr, Jarle; Lang, Thomas; Balk, Lennart

    2006-01-08

    The North Sea is a highly productive area with large fish populations that have been extensively harvested over the past century. North Sea fisheries remain important to the surrounding countries despite declining fish stocks over the past decades. The main reason for declining fish stocks is nearly certainly overfishing, but other environmental pressures also affect fish populations, such as eutrophication, climate change, and exposure to metals and organic pollutants, including polyaromatic hydrocarbons (PAHs), alkylphenols, and organochlorine compounds. There are three main sources of organic pollutants in the North Sea: atmospheric, land-based sources, and inputs from offshore gas and oil installations. All three sources contribute to elevated concentrations of organic pollutants in the North Sea compared to the Norwegian Sea. There is evidence that chlorinated organic contaminants were present in sufficiently high concentrations in the southern North Sea two decades ago, to alter embryonal development in fish. The results from extensive, long-term monitoring programs show that some diseases decreased whereas other increased in the southern North Sea and that, among other factors, contaminants may play a role in the temporal changes recorded in disease prevalence. Recent studies demonstrated that components in offshore effluents may affect fish reproduction and that tissues of fish near oil rigs are structurally different to tissues of fish from reference areas. Data on effluents from offshore activities have recently become available through an international workshop (BECPELAG) and follow-up studies.

  3. Sea level changes in the Holocene

    SciTech Connect

    Tanner, W.F. )

    1993-03-01

    Beach ridge data provide much information on the history of sea level changes through all of Holocene time. Two data sets start at about 12,000 B.P., one of them essentially continuous to now with data every 40--50 yrs. Another starting at 7,600 B.P. is continuous to the present. Others span the last 3,200 years. These records agree reasonably closely, and show the Little Ice Age (since 1,200 A.D.). The sea level changes in these data include the following: (a) Early Holocene crisis, about 8,000 B.P. The Swedish (Baltic Sea) record ends about this time, the Hudson Bay record starts at roughly this time, and the Danish record has a 300--500-year gap at about this time. From the latter, it appears that sea level rose sharply, shortly before 8,000 B.P., and fell again shortly after 8,000 B.P. These were the largest changes in Holocene time. The vertical change may have been as much as 12--18 meters, and the rate of change as much as 5--8 cm/yr, perhaps the maximum possible. In stable areas, evidence for these changes are now 25--30 meters below sea level. (b) Early Holocene general rise, up to about 8,000 B.P. Evidence for this is now known only on uplifted coasts. (c) Middle Holocene high, 2 m above present MSL 7,000--5,500 B.P. (d) Middle Holocene low, 3--4 m below present MSL 5,000--3,500 B.P. (e) Several changes up to 2 meters, especially since 3,000 B.P. In general, rates of change have been close to 1 cm/yr (major exceptions noted above). The only persistent interval was that between beach ridges; each ridge and its associated swale seem to have been built by a sea-level rise-and-fall couplet, having dimensions so small (perhaps 5--30 cm) that they could be overlooked easily on tide-gauge records. The average apparent time interval was 35--50 years.

  4. Coastal subsidence and relative sea level rise

    USGS Publications Warehouse

    Ingebritsen, Steven E.; Galloway, Devin L.

    2014-01-01

    Subsurface fluid-pressure declines caused by pumping of groundwater or hydrocarbons can lead to aquifer-system compaction and consequent land subsidence. This subsidence can be rapid, as much as 30 cm per year in some instances, and large, totaling more than 13 m in extreme examples. Thus anthropogenic subsidence may be the dominant contributor to relative sea-level rise in coastal environments where subsurface fluids are heavily exploited. Maximum observed rates of human-induced subsidence greatly exceed the rates of natural subsidence of unconsolidated sediments (~0.1–1 cm yr−1) and the estimated rates of ongoing global sea-level rise (~0.3 cm yr−1).

  5. Sea-level changes before large earthquakes

    USGS Publications Warehouse

    Wyss, M.

    1978-01-01

    Changes in sea level have long been used as a measure of local uplift and subsidence associated with large earthquakes. For instance, in 1835, the British naturalist Charles Darwin observed that sea level dropped by 2.7 meters during the large earthquake in Concepcion, CHile. From this piece of evidence and the terraces along the beach that he saw, Darwin concluded that the Andes had grown to their present height through earthquakes. Much more recently, George Plafker and James C. Savage of the U.S Geological Survey have shown, from barnacle lines, that the great 1960 Chile and the 1964 Alaska earthquakes caused several meters of vertical displacement of the shoreline. 

  6. Hurricanes, sea level rise, and coastal change

    USGS Publications Warehouse

    Sallenger,, Asbury H.; Wang, Ping; Rosati, Julie D.; Roberts, Tiffany M.

    2011-01-01

    Sixteen hurricanes have made landfall along the U.S. east and Gulf coasts over the past decade. For most of these storms, the USGS with our partners in NASA and the U.S. Army Corps of Engineers have flown before and after lidar missions to detect changes in beaches and dunes. The most dramatic changes occurred when the coasts were completely submerged in an inundation regime. Where this occurred locally, a new breach was cut, like during Hurricane Isabel in North Carolina. Where surge inundated an entire island, the sand was stripped off leaving marshy outcrops behind, like during Hurricane Katrina in Louisiana. Sea level rise together with sand starvation and repeated hurricane impacts could increase the probabilities of inundation and degrade coasts more than sea level rise alone.

  7. Rising Sea Levels: Truth or Scare?

    ERIC Educational Resources Information Center

    Peacock, Alan

    2007-01-01

    When "ITV News" ran an item that shocked the author, about rising sea levels that will have caused the entire evacuation of the islands by the end of this year, he began to wonder whether the Pacific Ocean is really rising as fast as this. The media reporting of such things can be a double-edged sword. On the one hand, it brought to the author's…

  8. Probabilistic reanalysis of twentieth-century sea-level rise.

    PubMed

    Hay, Carling C; Morrow, Eric; Kopp, Robert E; Mitrovica, Jerry X

    2015-01-22

    Estimating and accounting for twentieth-century global mean sea level (GMSL) rise is critical to characterizing current and future human-induced sea-level change. Several previous analyses of tide gauge records--employing different methods to accommodate the spatial sparsity and temporal incompleteness of the data and to constrain the geometry of long-term sea-level change--have concluded that GMSL rose over the twentieth century at a mean rate of 1.6 to 1.9 millimetres per year. Efforts to account for this rate by summing estimates of individual contributions from glacier and ice-sheet mass loss, ocean thermal expansion, and changes in land water storage fall significantly short in the period before 1990. The failure to close the budget of GMSL during this period has led to suggestions that several contributions may have been systematically underestimated. However, the extent to which the limitations of tide gauge analyses have affected estimates of the GMSL rate of change is unclear. Here we revisit estimates of twentieth-century GMSL rise using probabilistic techniques and find a rate of GMSL rise from 1901 to 1990 of 1.2 ± 0.2 millimetres per year (90% confidence interval). Based on individual contributions tabulated in the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, this estimate closes the twentieth-century sea-level budget. Our analysis, which combines tide gauge records with physics-based and model-derived geometries of the various contributing signals, also indicates that GMSL rose at a rate of 3.0 ± 0.7 millimetres per year between 1993 and 2010, consistent with prior estimates from tide gauge records.The increase in rate relative to the 1901-90 trend is accordingly larger than previously thought; this revision may affect some projections of future sea-level rise.

  9. The Impact of Sea Level Rise on Florida's Everglades

    NASA Astrophysics Data System (ADS)

    Senarath, S. U.

    2005-12-01

    Global warming and the resulting melting of polar ice sheets could increase global sea levels significantly. Some studies have predicted mean sea level increases in the order of six inches to one foot in the next 25 to 50 years. This could have severe irreversible impacts on low-lying areas of Florida's Everglades. The key objective of this study is to evaluate the effects of a one foot sea level rise on Cape Sable Seaside Sparrow (CSSS) nesting areas within the Everglades National Park (ENP). A regional-scale hydrologic model is used to assess the sensitivities of this sea-level rise scenario. Florida's Everglades supports a unique ecosystem. At present, about 50 percent of this unique ecosystem has been lost due to urbanization and farming. Today, the water flow in the remnant Everglades is also regulated to meet a variety of competing environmental, water-supply and flood-control needs. A 30-year, eight billion dollar (1999 estimate) project has been initiated to improve Everglades' water flows. The expected benefits of this restoration project will be short-lived if the predicted sea level rise causes severe impacts on the environmentally sensitive areas of the Everglades. Florida's Everglades is home to many threatened and endangered species of wildlife. The Cape Sable Seaside Sparrow population in the ENP is one such species that is currently listed as endangered. Since these birds build their nests close to the ground surface (the base of the nest is approximately six inches from the ground surface), they are directly affected by any sea level induced ponding depth, frequency or duration change. Therefore, the CSSS population serves as a good indicator species for evaluating the negative impacts of sea level rise on the Everglades' ecosystem. The impact of sea level rise on the CSSS habitat is evaluated using the Regional Simulation Model (RSM) developed by the South Florida Water Management District. The RSM is an implicit, finite-volume, continuous

  10. History of coral reefs and sea level

    SciTech Connect

    Fairbridge, R.W.

    1985-01-01

    Charles Darwin proposed crustal subsidence for atoll growth, on the Beagle, between England and Brazil, before even seeing a coral reef, on the basis of charts and discussions with Captain Fitzroy. Relative change of sea level due to crustal movements was then well-accepted from evidence of raised strandlines in Scandinavia and Scotland and sunken forests in England. Darwin added global change of sea level (tectonoeustasy) caused by remote tectonic activity, as explained by Robert Chambers (1848, p. 319). The glacioeustasy concept was mooted soon afterwards, though the term itself came later. When Suess in 1888 proposed eustatic change, he had in mind Archimedian displacement of water by sediment or lava accumulation on the sea floor. Integrated ideas of reef development also came in the 20th century. The powerful arguments against Darwin were led by Murray with his solution hypothesis, which can not be judged as good observation but from a narrow viewpoint. The Royal Society reef borings at Funafuti were heroic but at the same time misread. Subsequently came isotopic geochemistry, absolute dating, the Milankovitch insolation theory, and plate tectonics. And much more field work. The result is an integrated reef growth theory.

  11. Revisiting sea level changes in the North Sea during the Anthropocene

    NASA Astrophysics Data System (ADS)

    Jensen, Jürgen; Dangendorf, Sönke; Wahl, Thomas; Niehüser, Sebastian

    2016-04-01

    The North Sea is one of the best instrumented ocean basins in the world. Here we revisit sea level changes in the North Sea region from tide gauges, satellite altimetry, hydrographic profiles and ocean reanalysis data from the beginning of the 19th century to present. This includes an overview of the sea level chapter of the North Sea Climate Change Assessment (NOSCCA) complemented by results from more recent investigations. The estimates of long-term changes from tide gauge records are significantly affected by vertical land motion (VLM), which is related to both the large-scale viscoelastic response of the solid earth to ice melting since the last deglaciation and local effects. Removing VLM (estimated from various data sources such as GPS, tide gauge minus altimetry and GIA) significantly reduces the spatial variability of long-term trends in the basin. VLM corrected tide gauge records suggest a transition from relatively moderate changes in the 19th century towards modern trends of roughly 1.5 mm/yr during the 20th century. Superimposed on the long-term changes there is a considerable inter-annual to multi-decadal variability. On inter-annual timescales this variability mainly reflects the barotropic response of the ocean to atmospheric forcing with the inverted barometer effect dominating along the UK and Norwegian coastlines and wind forcing controlling the southeastern part of the basin. The decadal variability is mostly remotely forced and dynamically linked to the North Atlantic via boundary waves in response to long-shore winds along the continental slope. These findings give valuable information about the required horizontal resolution of ocean models and the necessary boundary conditions and are therefore important for the dynamical downscaling of sea level projections for the North Sea coastlines.

  12. Probabilistic assessment of sea level during the last interglacial stage.

    PubMed

    Kopp, Robert E; Simons, Frederik J; Mitrovica, Jerry X; Maloof, Adam C; Oppenheimer, Michael

    2009-12-17

    With polar temperatures approximately 3-5 degrees C warmer than today, the last interglacial stage (approximately 125 kyr ago) serves as a partial analogue for 1-2 degrees C global warming scenarios. Geological records from several sites indicate that local sea levels during the last interglacial were higher than today, but because local sea levels differ from global sea level, accurately reconstructing past global sea level requires an integrated analysis of globally distributed data sets. Here we present an extensive compilation of local sea level indicators and a statistical approach for estimating global sea level, local sea levels, ice sheet volumes and their associated uncertainties. We find a 95% probability that global sea level peaked at least 6.6 m higher than today during the last interglacial; it is likely (67% probability) to have exceeded 8.0 m but is unlikely (33% probability) to have exceeded 9.4 m. When global sea level was close to its current level (>or=-10 m), the millennial average rate of global sea level rise is very likely to have exceeded 5.6 m kyr(-1) but is unlikely to have exceeded 9.2 m kyr(-1). Our analysis extends previous last interglacial sea level studies by integrating literature observations within a probabilistic framework that accounts for the physics of sea level change. The results highlight the long-term vulnerability of ice sheets to even relatively low levels of sustained global warming.

  13. Sea-level rise: towards understanding local vulnerability

    NASA Astrophysics Data System (ADS)

    Rahmstorf, Stefan

    2012-06-01

    , experts are increasingly looking at its potential impacts on coasts to facilitate local adaptation planning. This is a more complex issue than one might think, because different stretches of coast can be affected in very different ways. First of all, the sea-level response to global warming will not be globally uniform, since factors like changes in ocean currents (Levermann et al 2005) and the changing gravitational pull of continental ice (Mitrovica et al 2001) affect the local rise. Secondly, superimposed on the climatic trend is natural variability in sea level, which regionally can be as large as the climatic signal on multi-decadal timescales. Over the past decades, sea level has dropped in sizable parts of the world ocean, although it has of course risen in global mean (IPCC 2007). Thirdly, local land uplift or subsidence affects the local sea-level change relative to the coast, both for natural reasons (post-glacial isostatic adjustment centred on regions that were covered by ice sheets during the last ice age) and artificial ones (e.g., extraction of water or oil as in the Gulf of Mexico). Finally, local vulnerability to sea-level rise depends on many factors. Two interesting new studies in this journal (Tebaldi et al 2012, Strauss et al 2012) make important steps towards understanding sea-level vulnerability along the coasts of the United States, with methods that could also be applied elsewhere. The first, by Strauss and colleagues, merges high-resolution topographic data and a newly available tidal model together with population and housing data in order to estimate what land area and population would be at risk given certain increments in sea level. The results are mapped and tabulated at county and city level. They reveal the 'hot spots' along the US coast where sea-level rise is of the highest concern because of large populations living near the high-tide line: New York City and Long Island; the New Jersey shore; the Norfolk, Virginia, area; near Charleston

  14. Anomalous secular sea-level acceleration in the Baltic Sea caused by glacial isostatic adjustment

    NASA Astrophysics Data System (ADS)

    Spada, Giorgio; Galassi, Gaia; Olivieri, Marco

    2014-05-01

    Observations from the global array of tide gauges show that global sea-level has been rising at an average rate of 1.5-2 mm/yr during the last ˜ 150 years (Spada & Galassi, 2012). Although a global sea-level acceleration was initially ruled out, subsequent studies have coherently proposed values of ˜1 mm/year/century (Olivieri & Spada, 2012). More complex non-linear trends and abrupt sea-level variations have now also been recognized. Globally, they could manifest a regime shift between the late Holocene and the current rhythms of sea-level rise, while locally they result from ocean circulation anomalies, steric effects and wind stress (Bromirski et al. 2011). Although isostatic readjustment affects the local rates of secular sea-level change, a possible impact on regional acceleration have been so far discounted (Woodworth et al., 2009) since the process evolves on a millennium scale. Here we report a previously unnoticed anomaly in the long-term sea-level acceleration of the Baltic Sea tide gauge records, and we explain it by the classical post-glacial rebound theory and numerical modeling of glacial isostasy. Contrary to previous assumptions, our findings demonstrate that isostatic compensation plays a role in the regional secular sea-level acceleration. In response to glacial isostatic adjustment (GIA), tide gauge records located along the coasts of the Baltic Sea exhibit a small - but significant - long-term sea-level acceleration in excess to those in the far field of previously glaciated regions. The sign and the amplitude of the anomaly is consistent with the post-glacial rebound theory and with realistic numerical predictions of GIA models routinely employed to decontaminate the tide gauges observations from the GIA effects (Peltier, 2004). Model computations predict the existence of anomalies of similar amplitude in other regions of the globe where GIA is still particularly vigorous at present, but no long-term instrumental observations are available to

  15. The impact of future changes in weather patterns on extreme sea levels over southern Australia

    NASA Astrophysics Data System (ADS)

    Colberg, Frank; McInnes, Kathleen L.

    This study first compares two methods by which the global, variable resolution Cubic Conformal Atmospheric Model (CCAM) is forced by reanalysis over Australia. The methods are the spectral nudging and bias-corrected sea surface temperature (SST) forcing. Surface winds and sea level pressure are compared since these influence coastal sea levels. SST forcing was found to better preserve the mean and standard deviation of these quantities. Second, a hydrodynamic model is used to model sea levels over southern Australia over 1980-1999 and 2080-2099 to investigate how changes in weather patterns affect extreme sea levels. Forcing from one Global Climate Model (GCM) and two CCAM simulations in which CCAM was used to downscale two GCMs over Australia with bias-corrected SST forcing (including the GCM considered in this study) were used. While there are differences in the spatial patterns of change between seasons over the modeled coastline between the three models, extreme sea levels were mostly lower in the future period over the southern mainland coastline from autumn to spring due to reduced westerlies in the climate models. The sea level changes around Tasmania varied from positive to negative depending on the model and season. The projected extreme sea level changes were within 10 cm of current climate values. This suggests that over southern Australia extreme sea level changes will be dominated by changes in mean sea level due to thermal expansion and ice sheet and glacier melt rather than changes in weather patterns.

  16. Differences between mean tide level and mean sea level

    NASA Astrophysics Data System (ADS)

    Woodworth, P. L.

    2017-01-01

    This paper discusses the differences between mean tide level (MTL) and mean sea level (MSL) as demonstrated using information from a global tide gauge data set. The roles of the two main contributors to differences between MTL and MSL (the M4 harmonic of the M2 semidiurnal tide, and the combination of the diurnal tides K1 and O1) are described, with a particular focus on the spatial scales of variation in MTL-MSL due to each contributor. Findings from the tide gauge data set are contrasted with those from a state-of-the-art global tide model. The study is of interest within tidal science, but also has practical importance regarding the type of mean level used to define land survey datums. In addition, an appreciation of MTL-MSL difference is important in the use of the historical sea level data used in climate change research, with implications for some of the data stored in international databanks. Particular studies are made of how MTL and MSL might differ through the year, and if MTL is measured in daylight hours only, as has been the practice of some national geodetic agencies on occasions in the past.

  17. Updating Maryland's sea-level rise projections

    USGS Publications Warehouse

    Boesch, Donald F.; Atkinson, Larry P.; Boicourt, William C.; Boon, John D.; Cahoon, Donald R.; Dalrymple, Robert A.; Ezer, Tal; Horton, Benjamin P.; Johnson, Zoe P.; Kopp, Robert E.; Li, Ming; Moss, Richard H.; Parris, Adam; Sommerfield, Christopher K.

    2013-01-01

    With its 3,100 miles of tidal shoreline and low-lying rural and urban lands, “The Free State” is one of the most vulnerable to sea-level rise. Historically, Marylanders have long had to contend with rising water levels along its Chesapeake Bay and Atlantic Ocean and coastal bay shores. Shorelines eroded and low-relief lands and islands, some previously inhabited, were inundated. Prior to the 20th century, this was largely due to the slow sinking of the land since Earth’s crust is still adjusting to the melting of large masses of ice following the last glacial period. Over the 20th century, however, the rate of rise of the average level of tidal waters with respect to land, or relative sea-level rise, has increased, at least partially as a result of global warming. Moreover, the scientific evidence is compelling that Earth’s climate will continue to warm and its oceans will rise even more rapidly. Recognizing the scientific consensus around global climate change, the contribution of human activities to it, and the vulnerability of Maryland’s people, property, public investments, and natural resources, Governor Martin O’Malley established the Maryland Commission on Climate Change on April 20, 2007. The Commission produced a Plan of Action that included a comprehensive climate change impact assessment, a greenhouse gas reduction strategy, and strategies for reducing Maryland’s vulnerability to climate change. The Plan has led to landmark legislation to reduce the state’s greenhouse gas emissions and a variety of state policies designed to reduce energy consumption and promote adaptation to climate change.

  18. Investigating the influence of sea level oscillations in the Danish Straits on the Baltic Sea dynamics

    NASA Astrophysics Data System (ADS)

    Tikhonova, Natalia; Gusev, Anatoly; Diansky, Nikolay; Zakharchuk, Evgeny

    2016-04-01

    related to the distance between the measurement point and open boundary. For example, in the Gulfs of Finland and Riga, the 36hr harmonic has an amplitude substantially higher than in the open sea, and in the Stockholm area, this harmonic is at the noise level. The 40dy and 121dy harmonics have slightly lower amplitudes than the original prescribed signal, but they are almost unchanged while propagating further into the sea, and in all the investigated locations have almost identical peaks of spectral density. The 3dy and 6dy harmonics significantly lost their amplitude in all parts of the sea, and spectral density peaks are at the noise level. The simulation results showed us that the Danish straits do not filter 121dy and 40dy oscillations, and their amplitude does not decrease much. The 13dy, 6dy and 3dy oscillations significantly lose in amplitude and have no significant peaks of the spectral density. The 1.5dy harmonic propagates to the Gulfs of Finland and Riga, and increases in amplitude due to resonance at the natural frequency of the basin. It is suggested that, while Danish straits do not filter or transform frequency characteristics of oscillations propagated from the North Sea, but the Baltic Sea configuration may affect the magnitude and propagation extent of these oscillations. Thus, the fluctuations in the North Sea and the Danish Straits can significantly contribute to the Baltic Sea dynamics in the low-frequency range of the spectrum, and the periods of natural oscillations of the basin. The research was supported by the Russian Foundation for Basic Research (grant № 16-05-00534) and Saint-Petersburg State University (grant №18.37.140.2014)

  19. Sea level rise, drought and the decline of Spartina patens in New England marshes

    EPA Science Inventory

    Already heavily impacted by coastal development, estuarine vegetated habitats (seagrasses, salt marshes, and mangroves) are increasingly affected by climate change via accelerated sea level rise, changes in the frequency and intensity of precipitation and storms, and warmer ocean...

  20. On how climate variability influences regional sea level change

    NASA Astrophysics Data System (ADS)

    Brunnabend, Sandra-Esther; Kusche, Jürgen; Rietbroek, Roelof; Forootan, Ehsan

    2016-04-01

    Regional trends in sea level change are strongly influenced by climate variations, such as ENSO (El-Nino Southern Oscillation), the IOD (Indian Ocean Dipole), or the PDO (Pacific Decadal Oscillation). Hence, before computing long term regional sea level change, these sea level variations need to be taken into account as they lead to strong dependencies of computed regional sea level trends on the time period of the investigation. In this study, sea level change during the years 1993 to 2013 is analysed to identify the dominant modes of sea level change caused by climate variations. Here, two different gridded altimetry products are analysed, namely ESA's combined CCI SeaLevel v1.1 ECV product (doi: 10.5270/esa-sea_level_cci-1993_2013-v_1.1-201412), and absolute dynamic topography produced by Ssalto/Duacs and distributed by Aviso, with support from Cnes (http://www.aviso.altimetry.fr/duacs/). Reconstructions using the different decomposition techniques including the standard principle component analysis (PCA), rotated empirical orthogonal functions (REOF) and independent component analysis (ICA) method are analysed. They are compared with sea level change modelled with the global finite-element sea-ice ocean model (FESOM). The results indicate that from the applied methods, ICA is most suitable to separate the individual climate variability signals in independent modes of sea level change. This especially holds for extracting the ENSO contribution in sea level changes, which was better separated by applying ICA, from both altimetry and modelled sea level products. In addition, it is presented how modelled sea level change reflects climate variations compared to that identified in the altimetry products.

  1. Incorporating Sediment Compaction Into a Gravitationally Self-consistent Model for Global Sea-level Change

    NASA Astrophysics Data System (ADS)

    Ferrier, K.; Mitrovica, J. X.

    2015-12-01

    In sedimentary deltas and fans, sea-level changes are strongly modulated by the deposition and compaction of marine sediment. The deposition of sediment and incorporation of water into the sedimentary pore space reduces sea level by increasing the elevation of the seafloor, which reduces the thickness of sea-water above the bed. In a similar manner, the compaction of sediment and purging of water out of the sedimentary pore space increases sea level by reducing the elevation of the seafloor, which increases the thickness of sea water above the bed. Here we show how one can incorporate the effects of sediment deposition and compaction into the global, gravitationally self-consistent sea-level model of Dalca et al. (2013). Incorporating sediment compaction requires accounting for only one additional quantity that had not been accounted for in Dalca et al. (2013): the mean porosity in the sediment column. We provide a general analytic framework for global sea-level changes including sediment deposition and compaction, and we demonstrate how sea level responds to deposition and compaction under one simple parameterization for compaction. The compaction of sediment generates changes in sea level only by changing the elevation of the seafloor. That is, sediment compaction does not affect the mass load on the crust, and therefore does not generate perturbations in crustal elevation or the gravity field that would further perturb sea level. These results have implications for understanding sedimentary effects on sea-level changes and thus for disentangling the various drivers of sea-level change. ReferencesDalca A.V., Ferrier K.L., Mitrovica J.X., Perron J.T., Milne G.A., Creveling J.R., 2013. On postglacial sea level - III. Incorporating sediment redistribution. Geophysical Journal International, doi: 10.1093/gji/ggt089.

  2. Distinguishing Between Natural and Anthropogenic Part of Sea Level Trends

    NASA Astrophysics Data System (ADS)

    Becker, M.; Karpytchev, M.; Lennartz-Sassinek, S.

    2014-12-01

    Detection and attribution of human influence on sea level rise are important topics that have not yet been explored in depth. From the perspective of assessing the contribution of human activities to climate changes, the sea level drivers can be partitioned in anthropogenic and natural forcing. In this study we try to answer the following two questions: (1) How large a sea level trend could be expected as result of natural internal variability? (2) Whether the sea level changes observed over the past century were natural in origin. We suppose that natural behavior of sea level consists of increases and decreases occurring with frequencies following a power law distribution and the monthly sea level records are power law long-term correlated time series. Then we search for the presence of unnatural external sea level trend by applying statistics of Lennartz and Bunde [2009]. We estimate the minimum anthropogenic sea level trend as a lower bound of statistically significant external sea level trend in the longest tide-gauge records worldwide. We apply this new method to distinguish between the trend-like natural oscillations and the external trends in the longest available sea level records and in global mean sea level reconstructions. The results show that the long-term persistence impacts strongly on sea level rise estimation. We provide statistical evidences that the observed sea level changes, at global and regional scales, are beyond its natural internal variability and cannot be explained without human influence. We found that sea level change during the past century contains an external component at 99% significance level in two thirds of the available longest tidal records worldwide. The anthropogenic sea level trend is about 1 mm/yr in global sea level reconstructions that is more than half of the total observed sea level trend during the XXth century, which is about 1.7 mm/yr. This work provides the first estimate of the minimal anthropogenic contribution

  3. Sea level trends for all sections of the Baltic Sea coastline

    NASA Astrophysics Data System (ADS)

    Madsen, Kristine S.; Høyer, Jacob L.; Suursaar, Ülo; Knudsen, Per; She, Jun

    2016-04-01

    To better understand influence of sea level rise on societal vulnerability and coastal erosion processes, it is important to know the sea level trend. The coastline of the Baltic Sea is not uniformly exposed, and therefore we will determine the sea level trend of the last 10, 50 and 100 years for all sections of the coastline. The observational record of sea level in the Baltic Sea is quite unique with several records of more than 100 years of data. However, the information is confined to the tide gauge locations. Here, we utilize a statistical method based on least squares regression and originally developed for short term sea level variability (Madsen et al. 2015, JGR, doi:10.1002/2015JC011070) to spread out the sea level information from selected tide gauges to all sections of the Baltic Sea coast. Monthly mean tide gauge observations are retrieved from PSMSL and supplemented with Estonian observations. The spatial distribution of the sea level is obtained from model reanalysis from the Copernicus Marine Service and satellite altimetry observations and land rise information is taken into account. Results are validated against independent tide gauges, providing a consistent record of 20th century sea level trends and variability, including uncertainties, for the entire Baltic Sea coastline. This work is sponsored by the EMODnet project Baltic Checkpoint.

  4. Twentieth century sea level: An enigma

    PubMed Central

    Munk, Walter

    2002-01-01

    Changes in sea level (relative to the moving crust) are associated with changes in ocean volume (mostly thermal expansion) and in ocean mass (melting and continental storage): ζ(t) = ζsteric(t) + ζeustatic(t). Recent compilations of global ocean temperatures by Levitus and coworkers are in accord with coupled ocean/atmosphere modeling of greenhouse warming; they yield an increase in 20th century ocean heat content by 2 × 1023 J (compared to 0.1 × 1023 J of atmospheric storage), which corresponds to ζgreenhouse(2000) = 3 cm. The greenhouse-related rate is accelerating, with a present value ζ̇greenhouse(2000) ≈ 6 cm/century. Tide records going back to the 19th century show no measurable acceleration throughout the late 19th and first half of the 20th century; we take ζ̇historic = 18 cm/century. The Intergovernmental Panel on Climate Change attributes about 6 cm/century to melting and other eustatic processes, leaving a residual of 12 cm of 20th century rise to be accounted for. The Levitus compilation has virtually foreclosed the attribution of the residual rise to ocean warming (notwithstanding our ignorance of the abyssal and Southern Oceans): the historic rise started too early, has too linear a trend, and is too large. Melting of polar ice sheets at the upper limit of the Intergovernmental Panel on Climate Change estimates could close the gap, but severe limits are imposed by the observed perturbations in Earth rotation. Among possible resolutions of the enigma are: a substantial reduction from traditional estimates (including ours) of 1.5–2 mm/y global sea level rise; a substantial increase in the estimates of 20th century ocean heat storage; and a substantial change in the interpretation of the astronomic record. PMID:12011419

  5. Twentieth century sea level: an enigma.

    PubMed

    Munk, Walter

    2002-05-14

    Changes in sea level (relative to the moving crust) are associated with changes in ocean volume (mostly thermal expansion) and in ocean mass (melting and continental storage): zeta(t) = zeta(steric)(t) + zeta(eustatic)(t). Recent compilations of global ocean temperatures by Levitus and coworkers are in accord with coupled ocean/atmosphere modeling of greenhouse warming; they yield an increase in 20th century ocean heat content by 2 x 10(23) J (compared to 0.1 x 10(23) J of atmospheric storage), which corresponds to zeta(greenhouse)(2000) = 3 cm. The greenhouse-related rate is accelerating, with a present value zeta(greenhouse)(2000) approximately 6 cm/century. Tide records going back to the 19th century show no measurable acceleration throughout the late 19th and first half of the 20th century; we take zeta(historic) = 18 cm/century. The Intergovernmental Panel on Climate Change attributes about 6 cm/century to melting and other eustatic processes, leaving a residual of 12 cm of 20th century rise to be accounted for. The Levitus compilation has virtually foreclosed the attribution of the residual rise to ocean warming (notwithstanding our ignorance of the abyssal and Southern Oceans): the historic rise started too early, has too linear a trend, and is too large. Melting of polar ice sheets at the upper limit of the Intergovernmental Panel on Climate Change estimates could close the gap, but severe limits are imposed by the observed perturbations in Earth rotation. Among possible resolutions of the enigma are: a substantial reduction from traditional estimates (including ours) of 1.5-2 mm/y global sea level rise; a substantial increase in the estimates of 20th century ocean heat storage; and a substantial change in the interpretation of the astronomic record.

  6. Sea Level Rise and Decadal Variations in the Ligurian Sea Inferred from the Medimaremetre Measurements.

    NASA Astrophysics Data System (ADS)

    Karpytchev, M.; Coulomb, A.; Vallee, M.

    2015-12-01

    Estimations of sea level rise over the last centuries are mostly based on the rare historical sea level records from tide gauge stations usually designed for navigational purposes. In this study, we examine the quality of sea level measurements performed by a mean sea level gauge operated in Nice from 1887 to 1909 and transferred to the nearby town of Villefranche-sur-Mer in 1913 where it stayed in operation untill 1974. The mean sea level gauges, called medimaremetres, were invented for geodetic studies and installed in many French ports since the end of the XIX century. By construction, the medimaremetre was connected to the sea through a porous porcelain crucible in order to filter out the tides and higher frequency sea level oscillations. Ucontrolled properties of the crucible and some systematic errors made the medimaremetre data to be ignored in the current sea level researches. We demonstrate that the Nice-Villefranche medimaremetre measurements are coherent with two available historical tide gauge records from Marseille and Genova and a new century-scale sea level series can be build up by combining the medimaremetre data with the those recorded by a tide gauge operating in Nice since the 1980s. We analyse the low frequency variabilities in Marseille, Nice-Villefranche and Genova and get new insights on the decadal sea level variations in the Ligurian Sea since the end of the XIX century.

  7. Timescales for detecting a significant acceleration in sea level rise

    PubMed Central

    Haigh, Ivan D.; Wahl, Thomas; Rohling, Eelco J.; Price, René M.; Pattiaratchi, Charitha B.; Calafat, Francisco M.; Dangendorf, Sönke

    2014-01-01

    There is observational evidence that global sea level is rising and there is concern that the rate of rise will increase, significantly threatening coastal communities. However, considerable debate remains as to whether the rate of sea level rise is currently increasing and, if so, by how much. Here we provide new insights into sea level accelerations by applying the main methods that have been used previously to search for accelerations in historical data, to identify the timings (with uncertainties) at which accelerations might first be recognized in a statistically significant manner (if not apparent already) in sea level records that we have artificially extended to 2100. We find that the most important approach to earliest possible detection of a significant sea level acceleration lies in improved understanding (and subsequent removal) of interannual to multidecadal variability in sea level records. PMID:24728012

  8. Global sea-level changes during the past century

    NASA Technical Reports Server (NTRS)

    Gornitz, Vivien; Lebedeff, Sergej

    1987-01-01

    A novel technique, initially developed for climate studies, is used to reevaluate the estimate of relative sea-level change over the past century. The technique produces a composite regional average sea-level curve from the tide-gage data of individual stations. The effects of glacioisostasy and long-term tectonism are accounted for using late Holocene sea-level indicators. Along the east coast of North America, an apparent maximum sea-level rise is detected in both tide-gage and late Holocene sea-level indicators between Chesapeake Bay and New Jersey. Sea-level changes in western North America reveal greater spatial variations than for the east coast, which can be related to more active tectonism in California and British Columbia and to strong localized isostatic rebound in Alaska.

  9. Timescales for detecting a significant acceleration in sea level rise.

    PubMed

    Haigh, Ivan D; Wahl, Thomas; Rohling, Eelco J; Price, René M; Pattiaratchi, Charitha B; Calafat, Francisco M; Dangendorf, Sönke

    2014-04-14

    There is observational evidence that global sea level is rising and there is concern that the rate of rise will increase, significantly threatening coastal communities. However, considerable debate remains as to whether the rate of sea level rise is currently increasing and, if so, by how much. Here we provide new insights into sea level accelerations by applying the main methods that have been used previously to search for accelerations in historical data, to identify the timings (with uncertainties) at which accelerations might first be recognized in a statistically significant manner (if not apparent already) in sea level records that we have artificially extended to 2100. We find that the most important approach to earliest possible detection of a significant sea level acceleration lies in improved understanding (and subsequent removal) of interannual to multidecadal variability in sea level records.

  10. Ice volume and sea level during the last interglacial.

    PubMed

    Dutton, A; Lambeck, K

    2012-07-13

    During the last interglacial period, ~125,000 years ago, sea level was at least several meters higher than at present, with substantial variability observed for peak sea level at geographically diverse sites. Speculation that the West Antarctic ice sheet collapsed during the last interglacial period has drawn particular interest to understanding climate and ice-sheet dynamics during this time interval. We provide an internally consistent database of coral U-Th ages to assess last interglacial sea-level observations in the context of isostatic modeling and stratigraphic evidence. These data indicate that global (eustatic) sea level peaked 5.5 to 9 meters above present sea level, requiring smaller ice sheets in both Greenland and Antarctica relative to today and indicating strong sea-level sensitivity to small changes in radiative forcing.

  11. Global sea level trend in the past century

    NASA Technical Reports Server (NTRS)

    Gornitz, V.; Lebedeff, S.; Hansen, J.

    1982-01-01

    Data derived from tide-gauge stations throughout the world indicate that the mean sea level rose by about 12 centimeters in the past century. The sea level change has a high correlation with the trend of global surface air temperature. A large part of the sea level rise can be accounted for in terms of the thermal expansion of the upper layers of the ocean. The results also represent weak indirect evidence for a net melting of the continental ice sheets.

  12. Controls on Precambrian sea level change and sedimentary cyclicity

    NASA Astrophysics Data System (ADS)

    Eriksson, P. G.; Catuneanu, O.; Nelson, D. R.; Popa, M.

    2005-04-01

    second-order cycles of considerably longer duration than Phanerozoic examples, supporting less evolved tectonism affecting cratonic plates. It is possible that oceanic tectonic realms underwent more rapid and dynamic plate movements and arc generation, whereas early continental cratonic plates offered more stable platforms and may have been subject to slower migration rates. The wide range of controls on Precambrian sea level change, allied to their apparent variability (in rates and periodicity) through Precambrian time supports the conclusion that each order of cyclicity is relative and must be defined within the stratigraphic context of each individual case study. This underlines the importance of establishing a hierarchical order of cyclicity in sequence stratigraphic interpretations of Precambrian basins based on the relative importance of sequences rather than their temporal duration.

  13. The social values at risk from sea-level rise

    SciTech Connect

    Graham, Sonia; Barnett, Jon; Fincher, Ruth; Hurlimann, Anna; Mortreux, Colette; Waters, Elissa

    2013-07-15

    Analysis of the risks of sea-level rise favours conventionally measured metrics such as the area of land that may be subsumed, the numbers of properties at risk, and the capital values of assets at risk. Despite this, it is clear that there exist many less material but no less important values at risk from sea-level rise. This paper re-theorises these multifarious social values at risk from sea-level rise, by explaining their diverse nature, and grounding them in the everyday practices of people living in coastal places. It is informed by a review and analysis of research on social values from within the fields of social impact assessment, human geography, psychology, decision analysis, and climate change adaptation. From this we propose that it is the ‘lived values’ of coastal places that are most at risk from sea-level rise. We then offer a framework that groups these lived values into five types: those that are physiological in nature, and those that relate to issues of security, belonging, esteem, and self-actualisation. This framework of lived values at risk from sea-level rise can guide empirical research investigating the social impacts of sea-level rise, as well as the impacts of actions to adapt to sea-level rise. It also offers a basis for identifying the distribution of related social outcomes across populations exposed to sea-level rise or sea-level rise policies.

  14. The Sea Level Conundrum: Insights From Paleo Studies

    NASA Astrophysics Data System (ADS)

    Siddall, Mark; Clark, Peter; Thompson, Bill; Waelbroeck, Claire; Gregory, Jonathan; Stocker, Thomas

    2009-03-01

    Empirical Constraints on Future Sea Level Rise; Bern, Switzerland, 25-29 August 2008; Eustatic sea level (ESL) rise during the 21st century is perhaps the greatest threat from climate change, but its magnitude is contested. Geological records identify examples of nonlinear ice sheet response to climate forcing, suggesting a strategy for refining estimates of 21st-century sea level change. In August 2008, Past Global Changes (PAGES), International Marine Past Global Change Study (IMAGES), and the University of Bern cosponsored a workshop to address this possibility. The workshop highlighted several ways that paleoceanography studies can place limits on future sea level rise, and these are enlarged upon here.

  15. Quantifying and Projecting Relative Sea-Level Rise At The Regional Scale: The Bangladesh Sea-Level Project (BanD-AID)

    NASA Astrophysics Data System (ADS)

    Shum, C. K.; Kuo, C. Y.; Guo, J.; Shang, K.; Tseng, K. H.; Wan, J.; Calmant, S.; Ballu, V.; Valty, P.; Kusche, J.; Hossain, F.; Khan, Z. H.; Rietbroek, R.; Uebbing, B.

    2014-12-01

    The potential for accelerated sea-level rise under anthropogenic warming is a significant societal problem, in particular in world's coastal deltaic regions where about half of the world's population resides. Quantifying geophysical sources of sea-level rise with the goal of improved projection at local scales remains a complex and challenging interdisciplinary research problem. These processes include ice-sheet/glacier ablations, steric sea-level, solid Earth uplift or subsidence due to GIA, tectonics, sediment loading or anthropogenic causes, hydrologic imbalance, and human processes including water retention in reservoirs and aquifer extraction. The 2013 IPCC AR5 concluded that the observed and explained geophysical causes of global geocentric sea-level rise, 1993-2010, is closer towards closure. However, the discrepancy reveals that circa 1.3→37.5% of the observed sea-level rise remains unexplained. This relatively large discrepancy is primarily attributable to the wide range of estimates of respective contributions of Greenland and Antarctic ice-sheets and mountain/peripheral glaciers to sea-level rise. Understanding and quantifying the natural and anthropogenic processes governing solid Earth (land, islands and sea-floor) uplift or subsidence at the regional and local scales remain elusive to enable addressing coastal vulnerability due to relative sea-level rise hazards, such as the Bangladesh Delta. This study focuses on addressing coastal vulnerability of Bangladesh, a Belmont Forum/IGFA project, BanD-AID (http://Belmont-SeaLevel.org). Sea-level rise, along with tectonic, sediment load and groundwater extraction induced land uplift/subsidence, have exacerbated Bangladesh's coastal vulnerability, affecting 150 million people in one of the world's most densely populated regions. Here we present preliminary results using space geodetic observations, including satellite radar and laser altimetry, GRACE gravity, tide gauge, hydrographic, and GPS/InSAR observed

  16. Estimation of Holocene Land Movement and Sea Level Changes in Southwest Scandinavia - Results From Interpretation of Relative Sea Level Curves

    NASA Astrophysics Data System (ADS)

    Nielsen, L.; Hede, M.; Clemmensen, L. B.; Morten Hansen, J.; Noe-Nygaard, N.; Sander, L.; Bendixen, M.; Kroon, A.; Murray, A. S.; Pejrup, M.

    2013-12-01

    Relative sea level curves from different localities in Denmark, southwest Scandinavia, are used for estimation of Holocene vertical land movement and absolute sea level variations in the gateway between the North Sea and the Baltic Sea. Two previous independent studies conducted in the area show that ground penetrating radar reflection images of internal beach ridge and swale architecture form a strong basis for estimation of relative sea level variation. Sediments are dated using optically stimulated luminescence (OSL); this shows that the beach ridges and swales were last exposed to daylight between ~6500 and 0 years ago. Time periods with characteristic changes in the rate of relative sea level change are identified at different localities. The observed relative sea level change rates differ in the study area, mainly because the different localities have experienced different isostatic rebound since the latest glaciation. Variations in uplift rates and absolute sea level change for the region are estimated by inversion of the observed relative sea level changes. The values obtained for the different time periods put constraints on absolute sea level variation during the Holocene and have implications for our understanding of the lithosphere's temporal response to the unloading caused by melting of the thick ice sheet formed during the latest glaciation in Scandinavia.

  17. A new Holocene sea-level database for the US Gulf Coast: Improving constraints for past and future sea levels

    NASA Astrophysics Data System (ADS)

    Hijma, M.; Tornqvist, T. E.; Hu, P.; Gonzalez, J.; Hill, D. F.; Horton, B. P.; Engelhart, S. E.

    2011-12-01

    The interpretation of present-day sea-level change, as well as the prediction of future relative sea-level (RSL) rise and its spatial variability, depend increasingly on the ability of glacial isostatic adjustment (GIA) models to reveal non-eustatic components of RSL change. GIA results from the redistribution of mass due to the growth and decay of ice sheets. As a consequence, formerly ice-covered areas are still rebounding and currently experience RSL fall, while in other areas the rate of RSL rise is enhanced due to glacial forebulge collapse. The development of GIA models relies to a large extent on the availability of quality-controlled Holocene RSL data. There is thus an urgent need for systematically compiled and publicly available databases of geological RSL data that can be used not only for the purposes mentioned above, but also can serve to underpin coastal management and policy decisions. We have focused our efforts to develop a Holocene sea-level database for the Atlantic and Gulf coasts of the US. Many of the research problems that can be addressed with this sea-level database revolve around the identification of crustal motions due to glacial forebulge collapse that affects the entire region and likely extends beyond South Florida. For the east coast, GIA-related subsidence rates have been calculated with unprecedented precision: <0.8 mm a-1 in Maine, increasing to rates of 1.7 mm a-1 in Delaware, and a return to rates <0.9 mm a-1 in the Carolinas. Here, we first define our methodology to reconstruct RSL, with particular reference to the quantification of age and elevation errors. Many sea-level indicators are related to a specific tide level (e.g., peat that formed between highest astronomical tide and mean high water level). We use paleotidal modeling to account for any changes during the Holocene. We furthermore highlight a number of errors associated with 14C dating that have rarely, if ever, been considered in previous studies of this nature

  18. The Impact of Groundwater Depletion on Spatial Variations in Sea Level Change During the Past Century

    NASA Astrophysics Data System (ADS)

    Conrad, C. P.; Veit, E.; Natarov, S.

    2015-12-01

    The loss of continental groundwater to the oceans during the past century has elevated sea level by ~25(±5) mm, and has caused ~0.7mm/yr of sea level rise since 2005. The mass unloading associated with this groundwater depletion induces elastic uplift of Earth's solid surface and depresses the gravitational equipotential surface that defines sea level. Together, these deflections should cause slower relative sea level rise near areas of continental groundwater loss. We estimated these variations in sea level change using a model of the solid Earth's response to estimates of groundwater depletion during the past century. We find large negative deviations in relative sea level near California, Western India, the western Yellow Sea and the eastern Mediterranean Sea. Relative sea level measured by tide gauges in these areas show slower sea level rise rates compared to global averages. For example, on the western coast of India (e.g., Karachi), groundwater-induced deviations from global average sea level rise can exceed -40 mm, and our model predicts ~1 mm/yr of sea level drop since 2005. Correcting tide gauge records for groundwater depletion using our model improves their fit to the global trend estimated by Church & White (2011), and further reduces the variation of rise rates observed among regional groups of stations. We reconstructed Global Mean Sea Level (GMSL) between 1930 and 2009 taking in account groundwater depletion corrections determined from our model. We found that including groundwater depletion increases our estimate of the global rate of change of GMSL from 1.81 to 1.88 mm/yr during this time period because the observed rise at some key stations is slowed by nearby groundwater depletion. For the past 20 years, including groundwater depletion increases GMSL from 3.32mm/yr to 3.46mm/yr. Quantifying the spatial variability of sea level associated with groundwater depletion is important for understanding the variety of factors that affect sea level, and

  19. Blending of satellite and tide gauge sea level observations and its assimilation in a storm surge model of the North Sea and Baltic Sea

    NASA Astrophysics Data System (ADS)

    Madsen, Kristine S.; Høyer, Jacob L.; Fu, Weiwei; Donlon, Craig

    2015-09-01

    Coastal storm surge forecasts are typically derived from dedicated hydrodynamic model systems, relying on Numerical Weather Prediction (NWP) inputs. Uncertainty in the NWP wind field affects both the preconditioning and the forecast of sea level. Traditionally, tide gauge data have been used to limit preconditioning errors, providing point information. Here we utilize coastal satellite altimetry sea level observations. Careful processing techniques allow data to be retrieved up to 3 km from the coast, combining 1 Hz and 20 Hz data. The use of satellite altimetry directly is limited to times when the satellite passes over the area of interest. Instead, we use a stationary blending method developed by Madsen et al. (2007) to relate the coastal satellite altimetry with corresponding tide gauge measurements, allowing generation of sea level maps whenever tide gauge data are available. We apply the method in the North Sea and Baltic Sea, including the coastal zone, and test it for operational nowcasting and hindcasting of the sea level. The feasibility to assimilate the blended product into a hydrodynamic model is assessed, using the ensemble optimal interpolation method. A 2 year test simulation shows decreased sea level root mean square error of 7-43% and improved correlation by 1-23% in all modeled areas, when validated against independent tide gauges, indicating the feasibility to limit preconditioning errors for storm surge forecasting, using a relatively cost effective assimilation scheme.

  20. Detecting anthropogenic footprints in sea level rise

    PubMed Central

    Dangendorf, Sönke; Marcos, Marta; Müller, Alfred; Zorita, Eduardo; Riva, Riccardo; Berk, Kevin; Jensen, Jürgen

    2015-01-01

    While there is scientific consensus that global and local mean sea level (GMSL and LMSL) has risen since the late nineteenth century, the relative contribution of natural and anthropogenic forcing remains unclear. Here we provide a probabilistic upper range of long-term persistent natural GMSL/LMSL variability (P=0.99), which in turn, determines the minimum/maximum anthropogenic contribution since 1900. To account for different spectral characteristics of various contributing processes, we separate LMSL into two components: a slowly varying volumetric component and a more rapidly changing atmospheric component. We find that the persistence of slow natural volumetric changes is underestimated in records where transient atmospheric processes dominate the spectrum. This leads to a local underestimation of possible natural trends of up to ∼1 mm per year erroneously enhancing the significance of anthropogenic footprints. The GMSL, however, remains unaffected by such biases. On the basis of a model assessment of the separate components, we conclude that it is virtually certain (P=0.99) that at least 45% of the observed increase in GMSL is of anthropogenic origin. PMID:26220773

  1. Bounding probabilistic sea-level projections within the framework of the possibility theory

    NASA Astrophysics Data System (ADS)

    Le Cozannet, Gonéri; Manceau, Jean-Charles; Rohmer, Jeremy

    2017-01-01

    Despite progresses in climate change science, projections of future sea-level rise remain highly uncertain, especially due to large unknowns in the melting processes affecting the ice-sheets in Greenland and Antarctica. Based on climate-models outcomes and the expertise of scientists concerned with these issues, the IPCC provided constraints to the quantiles of sea-level projections. Moreover, additional physical limits to future sea-level rise have been established, although approximately. However, many probability functions can comply with this imprecise knowledge. In this contribution, we provide a framework based on extra-probabilistic theories (namely the possibility theory) to model the uncertainties in sea-level rise projections by 2100 under the RCP 8.5 scenario. The results provide a concise representation of uncertainties in future sea-level rise and of their intrinsically imprecise nature, including a maximum bound of the total uncertainty. Today, coastal impact studies are increasingly moving away from deterministic sea-level projections, which underestimate the expectancy of damages and adaptation needs compared to probabilistic laws. However, we show that the probability functions used so-far have only explored a rather conservative subset of sea-level projections compliant with the IPCC. As a consequence, coastal impact studies relying on these probabilistic sea-level projections are expected to underestimate the possibility of large damages and adaptation needs.

  2. Future sea level rise constrained by observations and long-term commitment

    PubMed Central

    Mengel, Matthias; Levermann, Anders; Frieler, Katja; Robinson, Alexander; Marzeion, Ben; Winkelmann, Ricarda

    2016-01-01

    Sea level has been steadily rising over the past century, predominantly due to anthropogenic climate change. The rate of sea level rise will keep increasing with continued global warming, and, even if temperatures are stabilized through the phasing out of greenhouse gas emissions, sea level is still expected to rise for centuries. This will affect coastal areas worldwide, and robust projections are needed to assess mitigation options and guide adaptation measures. Here we combine the equilibrium response of the main sea level rise contributions with their last century's observed contribution to constrain projections of future sea level rise. Our model is calibrated to a set of observations for each contribution, and the observational and climate uncertainties are combined to produce uncertainty ranges for 21st century sea level rise. We project anthropogenic sea level rise of 28–56 cm, 37–77 cm, and 57–131 cm in 2100 for the greenhouse gas concentration scenarios RCP26, RCP45, and RCP85, respectively. Our uncertainty ranges for total sea level rise overlap with the process-based estimates of the Intergovernmental Panel on Climate Change. The “constrained extrapolation” approach generalizes earlier global semiempirical models and may therefore lead to a better understanding of the discrepancies with process-based projections. PMID:26903648

  3. Future sea level rise constrained by observations and long-term commitment.

    PubMed

    Mengel, Matthias; Levermann, Anders; Frieler, Katja; Robinson, Alexander; Marzeion, Ben; Winkelmann, Ricarda

    2016-03-08

    Sea level has been steadily rising over the past century, predominantly due to anthropogenic climate change. The rate of sea level rise will keep increasing with continued global warming, and, even if temperatures are stabilized through the phasing out of greenhouse gas emissions, sea level is still expected to rise for centuries. This will affect coastal areas worldwide, and robust projections are needed to assess mitigation options and guide adaptation measures. Here we combine the equilibrium response of the main sea level rise contributions with their last century's observed contribution to constrain projections of future sea level rise. Our model is calibrated to a set of observations for each contribution, and the observational and climate uncertainties are combined to produce uncertainty ranges for 21st century sea level rise. We project anthropogenic sea level rise of 28-56 cm, 37-77 cm, and 57-131 cm in 2100 for the greenhouse gas concentration scenarios RCP26, RCP45, and RCP85, respectively. Our uncertainty ranges for total sea level rise overlap with the process-based estimates of the Intergovernmental Panel on Climate Change. The "constrained extrapolation" approach generalizes earlier global semiempirical models and may therefore lead to a better understanding of the discrepancies with process-based projections.

  4. Numerical study of the Azov Sea level seiche oscillations

    NASA Astrophysics Data System (ADS)

    Matishov, G. G.; Inzhebeikin, Yu. I.

    2009-08-01

    Seiche oscillations of the Azov Sea level are studied on the basis of the developed two-dimensional numerical hydrodynamic model grounded on the shallow water theory and recent data on the morphometric characteristics of the Sea of Azov. Frequency and spatial characteristics of the first five modes corresponding to seiche oscillations of the Azov Sea level are computed. It is shown that the frequency and spatial characteristics of the first five modes obtained for the Sea of Azov level changes correspond to seiche oscillations. The calculated parameters are compared with the field observations, which show their realistic character.

  5. Recent Changes in Land Water Storage and its Contribution to Sea Level Variations

    NASA Astrophysics Data System (ADS)

    Wada, Yoshihide; Reager, John T.; Chao, Benjamin F.; Wang, Jida; Lo, Min-Hui; Song, Chunqiao; Li, Yuwen; Gardner, Alex S.

    2016-11-01

    Sea level rise is generally attributed to increased ocean heat content and increased rates glacier and ice melt. However, human transformations of Earth's surface have impacted water exchange between land, atmosphere, and ocean, ultimately affecting global sea level variations. Impoundment of water in reservoirs and artificial lakes has reduced the outflow of water to the sea, while river runoff has increased due to groundwater mining, wetland and endorheic lake storage losses, and deforestation. In addition, climate-driven changes in land water stores can have a large impact on global sea level variations over decadal timescales. Here, we review each component of negative and positive land water contribution separately in order to highlight and understand recent changes in land water contribution to sea level variations.

  6. Recent Changes in Land Water Storage and its Contribution to Sea Level Variations

    NASA Astrophysics Data System (ADS)

    Wada, Yoshihide; Reager, John T.; Chao, Benjamin F.; Wang, Jida; Lo, Min-Hui; Song, Chunqiao; Li, Yuwen; Gardner, Alex S.

    2017-01-01

    Sea level rise is generally attributed to increased ocean heat content and increased rates glacier and ice melt. However, human transformations of Earth's surface have impacted water exchange between land, atmosphere, and ocean, ultimately affecting global sea level variations. Impoundment of water in reservoirs and artificial lakes has reduced the outflow of water to the sea, while river runoff has increased due to groundwater mining, wetland and endorheic lake storage losses, and deforestation. In addition, climate-driven changes in land water stores can have a large impact on global sea level variations over decadal timescales. Here, we review each component of negative and positive land water contribution separately in order to highlight and understand recent changes in land water contribution to sea level variations.

  7. Recent Changes in Land Water Storage and Its Contribution to Sea Level Variations

    NASA Technical Reports Server (NTRS)

    Wada, Yoshihide; Reager, John T.; Chao, Benjamin F.; Wang, Jida; Lo, Min-Hui; Song, Chunqiao; Li, Yuwen; Gardner, Alex S.

    2016-01-01

    Sea level rise is generally attributed to increased ocean heat content and increased rates glacier and ice melt. However, human transformations of Earth's surface have impacted water exchange between land, atmosphere, and ocean, ultimately affecting global sea level variations. Impoundment of water in reservoirs and artificial lakes has reduced the outflow of water to the sea, while river runoff has increased due to groundwater mining, wetland and endorheic lake storage losses, and deforestation. In addition, climate-driven changes in land water stores can have a large impact on global sea level variations over decadal timescales. Here, we review each component of negative and positive land water contribution separately in order to highlight and understand recent changes in land water contribution to sea level variations.

  8. Modeling radium distribution in coastal aquifers during sea level changes: The Dead Sea case

    USGS Publications Warehouse

    Kiro, Yael; Yechieli, Yoseph; Voss, Clifford I.; Starinsky, Abraham; Weinstein, Yishai

    2012-01-01

    We present a new approach to studying the behavior of radium isotopes in a coastal aquifer. In order to simulate radium isotope distributions in the dynamic flow field of the Dead Sea aquifer, a multi-species density dependent flow model (SUTRA-MS) was used. Field data show that the activity of 226Ra decreases from 140 to 60 dpm/L upon entering the aquifer from the Dead Sea, and then further decreases linearly due to mixing with Ra-poor fresh water. On the other hand, an increase is observed in the activity of the shorter-lived isotopes (up to 52 dpm/L 224Ra and 31 dpm/L 223Ra), which are relatively low in Dead Sea water (up to 2.5 dpm/L 224Ra and 0.5 dpm/L 223Ra). The activities of the short lived radium isotopes also decrease with decreasing salinity, which is due to the effect of salinity on the adsorption of radium. The relationship between 224Ra and salinity suggests that the adsorption partition coefficient (K) is linearly related to salinity. Simulations of the steady-state conditions, show that the distance where equilibrium activity is attained for each radium isotope is affected by the isotope half-life, K and the groundwater velocity, resulting in a longer distance for the long-lived radium isotopes. K affects the radium distribution in transient conditions, especially that of the long-lived radium isotopes. The transient conditions in the Dead Sea system, with a 1 m/yr lake level drop, together with the radium field data, constrains K to be relatively low (226Ra cannot be explained by adsorption, and it is better explained by removal via coprecipitation, probably with barite or celestine.

  9. A search for scale in sea-level studies

    USGS Publications Warehouse

    Larsen, C.E.; Clark, I.

    2006-01-01

    Many researchers assume a proportional relationship among the atmospheric CO2 concentration, temperature, and sea level. Thus, the rate of sea-level rise should increase in concert with the documented exponential increase in CO2. Although sea surface temperature has increased in places over the past century and short-term sea level rose abruptly during the 1990s, it is difficult to demonstrate a proportional relationship using existing geologic or historic records. Tide gauge records in the United States cover too short a time interval to verify acceleration in the rate of sea-level rise, although multicentury tide gauge and staff records from the Netherlands and Sweden suggest a mid-19th-century acceleration in sea-level rise. Reconstructions of sea-level changes for the past 1000 years derived using benthic foraminifer data from salt marshes along the East Coast of the United States suggest an increased rate of relative sea-level rise beginning in the 1600s. Geologic records of relative sea-level rise for the past 6000 years are available for several sites along the US East Coast from 14C-dated basal peat below salt marshes and estuarine sediments. When these three scales of sea-level variation are integrated, adjusted for postglacial isostatic movement, and replotted, the range of variation in sea level suggested by basal peat ages is within ??1 meter of the long-term trend. The reconstruction from Long Island Sound data shows a linear rise in sea level beginning in the mid-1600s at a rate consistent with the historic record of mean high water. Long-term tide gauge records from Europe and North America show similar trends since the mid-19th century. There is no clear proportional exponential increase in the rate of sea-level rise. If proportionality exists among sea level, atmospheric CO2, and temperature, there may be a significant time lag before an anthropogenic increase in the rate of sea-level rise occurs.

  10. Toxic Diatom Aldehydes Affect Defence Gene Networks in Sea Urchins

    PubMed Central

    Varrella, Stefano; Ruocco, Nadia; Ianora, Adrianna; Bentley, Matt G.; Costantini, Maria

    2016-01-01

    Marine organisms possess a series of cellular strategies to counteract the negative effects of toxic compounds, including the massive reorganization of gene expression networks. Here we report the modulated dose-dependent response of activated genes by diatom polyunsaturated aldehydes (PUAs) in the sea urchin Paracentrotus lividus. PUAs are secondary metabolites deriving from the oxidation of fatty acids, inducing deleterious effects on the reproduction and development of planktonic and benthic organisms that feed on these unicellular algae and with anti-cancer activity. Our previous results showed that PUAs target several genes, implicated in different functional processes in this sea urchin. Using interactomic Ingenuity Pathway Analysis we now show that the genes targeted by PUAs are correlated with four HUB genes, NF-κB, p53, δ-2-catenin and HIF1A, which have not been previously reported for P. lividus. We propose a working model describing hypothetical pathways potentially involved in toxic aldehyde stress response in sea urchins. This represents the first report on gene networks affected by PUAs, opening new perspectives in understanding the cellular mechanisms underlying the response of benthic organisms to diatom exposure. PMID:26914213

  11. Sea Level Trend and Variability in the Straits of Singapore and Malacca

    NASA Astrophysics Data System (ADS)

    Luu, Q.; Tkalich, P.

    2013-12-01

    of -0.7 (in correspondence with the Multivariate ENSO Index). The IOD modulates interannual sea level variability only in the Malacca Strait in the range of ×3 cm with a correlation coefficient of -0.6 (with respect to the Dipole Mode Index). At annual scale, SLAs in the SSM are mainly monsoon-driven; of the order of 20 cm. Mean sea level in the Singapore Strait reach the peak during northeast monsoon and trough during southwest monsoon; while these in the Malacca Strait are highest at middle of both monsoons and lowest during their transitional monsoonal seasons. Global and regional signals are quantitatively captured in the SSM. In comparison with the global sea level trends, SSM sea level rise are larger for recent decades 1984-2009. Taking into account the rough estimate of land subsidence rates in Singapore (2006-2011) and Peninsular Malaysia (1994-2004), the trend of absolute sea level rise in SSM follows regional tendency. At interannual scale, ENSO modulates sea level variabilities in the entire SSM region, while IOD affects the Malacca Strait only. At annual scale, sea level responds differently to the Asian monsoon: quasi-periodic cycles are observed twice a year in the Malacca Strait, but once a year in the Singapore Strait. Such behavior implies that the narrow channel constriction between the Singapore and Malacca Straits may be a reason of different variability of sea level in the domains.

  12. Impact of sea-level rise on sea water intrusion in coastal aquifers.

    PubMed

    Werner, Adrian D; Simmons, Craig T

    2009-01-01

    Despite its purported importance, previous studies of the influence of sea-level rise on coastal aquifers have focused on specific sites, and a generalized systematic analysis of the general case of the sea water intrusion response to sea-level rise has not been reported. In this study, a simple conceptual framework is used to provide a first-order assessment of sea water intrusion changes in coastal unconfined aquifers in response to sea-level rise. Two conceptual models are tested: (1) flux-controlled systems, in which ground water discharge to the sea is persistent despite changes in sea level, and (2) head-controlled systems, whereby ground water abstractions or surface features maintain the head condition in the aquifer despite sea-level changes. The conceptualization assumes steady-state conditions, a sharp interface sea water-fresh water transition zone, homogeneous and isotropic aquifer properties, and constant recharge. In the case of constant flux conditions, the upper limit for sea water intrusion due to sea-level rise (up to 1.5 m is tested) is no greater than 50 m for typical values of recharge, hydraulic conductivity, and aquifer depth. This is in striking contrast to the constant head cases, in which the magnitude of salt water toe migration is on the order of hundreds of meters to several kilometers for the same sea-level rise. This study has highlighted the importance of inland boundary conditions on the sea-level rise impact. It identifies combinations of hydrogeologic parameters that control whether large or small salt water toe migration will occur for any given change in a hydrogeologic variable.

  13. Holocene sea level variations on the basis of integration of independent data sets

    SciTech Connect

    Sahagian, D.; Berkman, P. . Dept. of Geological Sciences and Byrd Polar Research Center)

    1992-01-01

    Variations in sea level through earth history have occurred at a wide variety of time scales. Sea level researchers have attacked the problem of measuring these sea level changes through a variety of approaches, each relevant only to the time scale in question, and usually only relevant to the specific locality from which a specific type of data are derived. There is a plethora of different data types that can and have been used (locally) for the measurement of Holocene sea level variations. The problem of merging different data sets for the purpose of constructing a global eustatic sea level curve for the Holocene has not previously been adequately addressed. The authors direct the efforts to that end. Numerous studies have been published regarding Holocene sea level changes. These have involved exposed fossil reef elevations, elevation of tidal deltas, elevation of depth of intertidal peat deposits, caves, tree rings, ice cores, moraines, eolian dune ridges, marine-cut terrace elevations, marine carbonate species, tide gauges, and lake level variations. Each of these data sets is based on particular set of assumptions, and is valid for a specific set of environments. In order to obtain the most accurate possible sea level curve for the Holocene, these data sets must be merged so that local and other influences can be filtered out of each data set. Since each data set involves very different measurements, each is scaled in order to define the sensitivity of the proxy measurement parameter to sea level, including error bounds. This effectively determines the temporal and spatial resolution of each data set. The level of independence of data sets is also quantified, in order to rule out the possibility of a common non-eustatic factor affecting more than one variety of data. The Holocene sea level curve is considered to be independent of other factors affecting the proxy data, and is taken to represent the relation between global ocean water and basin volumes.

  14. Late Holocene sea-level change in Arctic Norway

    NASA Astrophysics Data System (ADS)

    Barnett, Robert L.; Gehrels, W. Roland; Charman, Dan J.; Saher, Margot H.; Marshall, William A.

    2015-01-01

    Relative sea-level data from the pre-industrial era are required for validating geophysical models of glacio-isostatic adjustment as well as for testing models used to make sea-level predictions based on future climate change scenarios. We present the first late Holocene (past ˜3300 years) relative sea-level reconstruction for northwestern Norway based on investigations in South Hinnøya in the Vesterålen - Lofoton archipelago. Sea-level changes are reconstructed from analyses of salt-marsh and estuarine sediments and the micro-organisms (foraminifera and testate amoebae) preserved within. The 'indicative meaning' of the microfauna is established from their modern distributions. Records are dated by radiocarbon, 201Pb, 137Cs and chemostratigraphical analyses. Our results show a continuous relative sea-level decline of 0.7-0.9 mm yr-1 for South Hinnøya during the late Holocene. The reconstruction extends the relative sea-level trend recorded by local tide gauge data which is only available for the past ˜25 years. Our reconstruction demonstrates that existing models of shoreline elevations and GIA overpredict sea-level positions during the late Holocene. We suggest that models might be adjusted in order to reconcile modelled and reconstructed sea-level changes and ultimately improve understanding of GIA in Fennoscandia.

  15. Uncertainties in sea level reconstructions due to GIA corrections

    NASA Astrophysics Data System (ADS)

    Jevrejeva, S.; Moore, J. C.; Grinsted, A.

    2012-12-01

    We use 1277 tide gauge records since 1807 to compose a global sea level reconstruction and analyse the evolution of sea level trend and acceleration. There is a good agreement between the rate of sea level rise (3.2 mm/yr) calculated from satellite altimetry and the rate of 3.1 mm/yr from tide gauge based reconstruction for the overlapping time period (1993-2009). The new reconstruction suggests a linear trend of 1.9 mm/yr during the 20th century, with only 1.5 mm/yr since 1960. Regional linear trends for 14 ocean basins since 1960 show the fastest sea level rise for the Arctic (3.8 mm/yr), Antarctica (3.5 mm/yr) and North West Pacific region (3.3 mm/yr). Choice of GIA correction is critical in the trends for the local and regional sea level, introducing up to 6 mm/yr uncertainties for individual tide gauge records, up to 2 mm/yr for regional curves and up to 0.8 mm/yr in global sea level reconstruction. We calculate an acceleration of 0.02 mm/yr in global sea level (1807-2010). In comparison the steric component of sea level shows and acceleration of 0.006 mm/yr 2 and mass loss of glaciers accelerates at 0. 003 mm/yr2 over 200 year long time series.

  16. Sea level oscillations over minute timescales: a global perspective

    NASA Astrophysics Data System (ADS)

    Vilibic, Ivica; Sepic, Jadranka

    2016-04-01

    Sea level oscillations occurring over minutes to a few hours are an important contributor to sea level extremes, and a knowledge on their behaviour is essential for proper quantification of coastal marine hazards. Tsunamis, meteotsunamis, infra-gravity waves and harbour oscillations may even dominate sea level extremes in certain areas and thus pose a great danger for humans and coastal infrastructure. Aside for tsunamis, which are, due to their enormous impact to the coastlines, a well-researched phenomena, the importance of other high-frequency oscillations to the sea level extremes is still underrated, as no systematic long-term measurements have been carried out at a minute timescales. Recently, Intergovernmental Oceanographic Commission (IOC) established Sea Level Monitoring Facility portal (http://www.ioc-sealevelmonitoring.org), making 1-min sea level data publicly available for several hundred tide gauge sites in the World Ocean. Thereafter, a global assessment of oscillations over tsunami timescales become possible; however, the portal contains raw sea level data only, being unchecked for spikes, shifts, drifts and other malfunctions of instruments. We present a quality assessment of these data, estimates of sea level variances and contributions of high-frequency processes to the extremes throughout the World Ocean. This is accompanied with assessment of atmospheric conditions and processes which generate intense high-frequency oscillations.

  17. Glacial Isostatic Adjustment and Contemporary Sea Level Rise: An Overview

    NASA Astrophysics Data System (ADS)

    Spada, Giorgio

    2017-01-01

    Glacial isostatic adjustment (GIA) encompasses a suite of geophysical phenomena accompanying the waxing and waning of continental-scale ice sheets. These involve the solid Earth, the oceans and the cryosphere both on short (decade to century) and on long (millennia) timescales. In the framework of contemporary sea-level change, the role of GIA is particular. In fact, among the processes significantly contributing to contemporary sea-level change, GIA is the only one for which deformational, gravitational and rotational effects are simultaneously operating, and for which the rheology of the solid Earth is essential. Here, I review the basic elements of the GIA theory, emphasizing the connections with current sea-level changes observed by tide gauges and altimetry. This purpose is met discussing the nature of the "sea-level equation" (SLE), which represents the basis for modeling the sea-level variations of glacial isostatic origin, also giving access to a full set of geodetic variations associated with GIA. Here, the SLE is employed to characterize the remarkable geographical variability of the GIA-induced sea-level variations, which are often expressed in terms of "fingerprints". Using harmonic analysis, the spatial variability of the GIA fingerprints is compared to that of other components of contemporary sea-level change. In closing, some attention is devoted to the importance of the "GIA corrections" in the context of modern sea-level observations, based on tide gauges or satellite altimeters.

  18. Does Sea Level Change when a Floating Iceberg Melts?

    ERIC Educational Resources Information Center

    Lan, Boon Leong

    2010-01-01

    On the answer page to a recent "Figuring Physics" question, the cute mouse asks another question: "Does the [sea] water level change if the iceberg melts?" The conventional answer is "no." However, in this paper I will show through a simple analysis involving Archimedes' principle that the sea level will rise. The analysis shows the wrong…

  19. Arctic Sea Level During the Satellite Altimetry Era

    NASA Astrophysics Data System (ADS)

    Carret, A.; Johannessen, J. A.; Andersen, O. B.; Ablain, M.; Prandi, P.; Blazquez, A.; Cazenave, A.

    2016-11-01

    Results of the sea-level budget in the high latitudes (up to 80°N) and the Arctic Ocean during the satellite altimetry era. We investigate the closure of the sea-level budget since 2002 using two altimetry sea-level datasets based on the Envisat waveform retracking: temperature and salinity data from the ORAP5 reanalysis, and Gravity Recovery And Climate Experiment (GRACE) space gravimetry data to estimate the steric and mass components. Regional sea-level trends seen in the altimetry map, in particular over the Beaufort Gyre and along the eastern coast of Greenland, are of halosteric origin. However, in terms of regional average over the region ranging from 66°N to 80°N, the steric component contributes little to the observed sea-level trend, suggesting a dominant mass contribution in the Arctic region. This is confirmed by GRACE-based ocean mass time series that agree well with the altimetry-based sea-level time series. Direct estimate of the mass component is not possible prior to GRACE. Thus, we estimated the mass contribution from the difference between the altimetry-based sea level and the steric component. We also investigate the coastal sea level with tide gauge records. Twenty coupled climate models from the CMIP5 project are also used. The models lead us to the same conclusions concerning the halosteric origin of the trend patterns.

  20. Glacial Isostatic Adjustment and Contemporary Sea Level Rise: An Overview

    NASA Astrophysics Data System (ADS)

    Spada, Giorgio

    2016-08-01

    Glacial isostatic adjustment (GIA) encompasses a suite of geophysical phenomena accompanying the waxing and waning of continental-scale ice sheets. These involve the solid Earth, the oceans and the cryosphere both on short (decade to century) and on long (millennia) timescales. In the framework of contemporary sea-level change, the role of GIA is particular. In fact, among the processes significantly contributing to contemporary sea-level change, GIA is the only one for which deformational, gravitational and rotational effects are simultaneously operating, and for which the rheology of the solid Earth is essential. Here, I review the basic elements of the GIA theory, emphasizing the connections with current sea-level changes observed by tide gauges and altimetry. This purpose is met discussing the nature of the "sea-level equation" (SLE), which represents the basis for modeling the sea-level variations of glacial isostatic origin, also giving access to a full set of geodetic variations associated with GIA. Here, the SLE is employed to characterize the remarkable geographical variability of the GIA-induced sea-level variations, which are often expressed in terms of "fingerprints". Using harmonic analysis, the spatial variability of the GIA fingerprints is compared to that of other components of contemporary sea-level change. In closing, some attention is devoted to the importance of the "GIA corrections" in the context of modern sea-level observations, based on tide gauges or satellite altimeters.

  1. Arctic Sea Level During the Satellite Altimetry Era

    NASA Astrophysics Data System (ADS)

    Carret, A.; Johannessen, J. A.; Andersen, O. B.; Ablain, M.; Prandi, P.; Blazquez, A.; Cazenave, A.

    2017-01-01

    Results of the sea-level budget in the high latitudes (up to 80°N) and the Arctic Ocean during the satellite altimetry era. We investigate the closure of the sea-level budget since 2002 using two altimetry sea-level datasets based on the Envisat waveform retracking: temperature and salinity data from the ORAP5 reanalysis, and Gravity Recovery And Climate Experiment (GRACE) space gravimetry data to estimate the steric and mass components. Regional sea-level trends seen in the altimetry map, in particular over the Beaufort Gyre and along the eastern coast of Greenland, are of halosteric origin. However, in terms of regional average over the region ranging from 66°N to 80°N, the steric component contributes little to the observed sea-level trend, suggesting a dominant mass contribution in the Arctic region. This is confirmed by GRACE-based ocean mass time series that agree well with the altimetry-based sea-level time series. Direct estimate of the mass component is not possible prior to GRACE. Thus, we estimated the mass contribution from the difference between the altimetry-based sea level and the steric component. We also investigate the coastal sea level with tide gauge records. Twenty coupled climate models from the CMIP5 project are also used. The models lead us to the same conclusions concerning the halosteric origin of the trend patterns.

  2. Time of emergence for regional sea-level change

    NASA Astrophysics Data System (ADS)

    Lyu, Kewei; Zhang, Xuebin; Church, John A.; Slangen, Aimée B. A.; Hu, Jianyu

    2014-11-01

    Determining the time when the climate change signal from increasing greenhouse gases exceeds and thus emerges from natural climate variability (referred to as the time of emergence, ToE) is an important climate change issue. Previous ToE studies were mainly focused on atmospheric variables. Here, based on three regional sea-level projection products available to 2100, which have increasing complexity in terms of included processes, we estimate the ToE for sea-level changes relative to the reference period 1986-2005. The dynamic sea level derived from ocean density and circulation changes alone leads to emergence over only limited regions. By adding the global-ocean thermal expansion effect, 50% of the ocean area will show emergence with rising sea level by the early-to-middle 2040s. Including additional contributions from land ice mass loss, land water storage change and glacial isostatic adjustment generally enhances the signal of regional sea-level rise (except in some regions with decreasing total sea levels), which leads to emergence over more than 50% of the ocean area by 2020. The ToE for total sea level is substantially earlier than that for surface air temperature and exhibits little dependence on the emission scenarios, which means that our society will face detectable sea-level change and its potential impacts earlier than surface air warming.

  3. Responding to rising sea levels in the Mekong Delta

    NASA Astrophysics Data System (ADS)

    Smajgl, A.; Toan, T. Q.; Nhan, D. K.; Ward, J.; Trung, N. H.; Tri, L. Q.; Tri, V. P. D.; Vu, P. T.

    2015-02-01

    Vietnamese communities in the Mekong Delta are faced with the substantial impacts of rising sea levels and salinity intrusion. The construction of embankments and dykes has historically been the principal strategy of the Vietnamese government to mitigate the effects of salinity intrusion on agricultural production. A predicted sea-level rise of 30 cm by the year 2050 is expected to accelerate salinity intrusion. This study combines hydrologic, agronomic and behavioural assessments to identify effective adaptation strategies reliant on land-use change (soft options) and investments in water infrastructure (hard options). As these strategies are managed within different policy portfolios, the political discussion has polarized between choices of either soft or hard options. This paper argues that an ensemble of hard and soft policies is likely to provide the most effective results for people's livelihoods in the Mekong Delta. The consequences of policy deliberations are likely to be felt beyond the Mekong Delta as levels of rice cultivation there also affect national and global food security.

  4. Sea-level responses to sediment transport over the last ice age cycle

    NASA Astrophysics Data System (ADS)

    Ferrier, K.; Mitrovica, J. X.

    2013-12-01

    Sea-level changes over the last ice age cycle were instrumental in steering Earth's topographic evolution. These sea-level variations were driven by changes in surface mass loads, including not only ice and ocean mass variations but also the transfer of rock from eroding mountains to sedimentary deposits. Here we use an extended numerical model of ice age sea level (Dalca et al., 2013) to explore how sediment erosion and deposition affected global sea-level variations over the last ice age cycle. The model takes histories of ice and sediment loads as inputs, and it computes gravitationally self-consistent sea level responses by accounting for the deformational, gravitational, and rotational perturbations in the Earth's viscoelastic form. In these model simulations, we use published estimates of erosion rates, sedimentation rates, and ice sheet variations to constrain sediment and ice loading since the Last Interglacial. We explore sea-level responses to several erosional and depositional scenarios, and in each we quantify the relative contributions of crustal deformation and gravitational perturbation to the computed sea-level change. We also present a case study to illustrate the effects that sediment transfer can have on sea level at the regional scale. In particular, we focus on the region surrounding the Indus River, where fluvial sediment fluxes are among the highest on Earth. Preliminary model results suggest that sediment fluxes from Asia to the ocean are large enough to produce a significant response in sea level along the northeastern coast of the Arabian Sea. Moreover, they suggest that modeled sea-level histories are sensitive to the timing and spatial distribution of sediment erosion and deposition. For instance, sediment deposition along the continental shelf - which may have been the primary site of Indus River sediment deposition during the Holocene - produces a different sea-level response than sediment deposition on the deep-sea Indus Fan, where

  5. Sea level data and techniques for detecting vertical crustal movements

    NASA Technical Reports Server (NTRS)

    Lennon, G. W.

    1978-01-01

    An attempt is made to survey problems, requirements, and the outlook for the future in the study of sea level time series so as to determine the relative movement of land and sea levels. The basic aim is to eliminate from the record the contributions from whatever marine dynamic phenomena respond to treatment, allowing the secular element to be identified with optimum clarity. Nevertheless the concept of sea level perturbation varies according to regional experience. The recent work of the Permanent Service for Mean Sea Level helps to eliminate geodetic noise from the series and makes it possible, perhaps, to treat the global mean sea level data bank so as to define eustatic changes in ocean volume which, in the present context, may be regarded as the final goal, allowing the identification of vertical crustal motion itself.

  6. Eustatic sea level fluctuations induced by polar wander

    NASA Technical Reports Server (NTRS)

    Sabadini, Roberto; Doglioni, Carlo; Yuen, David A.

    1990-01-01

    It is shown here that polar wander of a viscoelastic, stratified earth can induce global sea level fluctuations comparable to the short-term component in eustatic sea-level curves. The sign of these fluctuations, which are very sensitive to the rheological stratification, depends on the geographical location of the observation point; rises and falls in sea level can thus be coeval in different parts of the world. This finding is a distinct contrast to the main assumption underlying the reconstruction of eustatic curves, namely that global sea-level events produce the same depositional sequence everywhere. It is proposed that polar wander should be added to the list of geophysical mechanisms that can control the third-order cycles in sea level.

  7. Continuous assimilation of simulated Geosat altimetric sea level into an eddy-resolving numerical ocean model. I - Sea level differences. II - Referenced sea level differences

    NASA Technical Reports Server (NTRS)

    White, Warren B.; Tai, Chang-Kou; Holland, William R.

    1990-01-01

    The optimal interpolation method of Lorenc (1981) was used to conduct continuous assimilation of altimetric sea level differences from the simulated Geosat exact repeat mission (ERM) into a three-layer quasi-geostrophic eddy-resolving numerical ocean box model that simulates the statistics of mesoscale eddy activity in the western North Pacific. Assimilation was conducted continuously as the Geosat tracks appeared in simulated real time/space, with each track repeating every 17 days, but occurring at different times and locations within the 17-day period, as would have occurred in a realistic nowcast situation. This interpolation method was also used to conduct the assimilation of referenced altimetric sea level differences into the same model, performing the referencing of altimetric sea sevel differences by using the simulated sea level. The results of this dynamical interpolation procedure are compared with those of a statistical (i.e., optimum) interpolation procedure.

  8. Acceleration of Sea Level Rise Over Malaysian Seas from Satellite Altimeter

    NASA Astrophysics Data System (ADS)

    Hamid, A. I. A.; Din, A. H. M.; Khalid, N. F.; Omar, K. M.

    2016-09-01

    Sea level rise becomes our concern nowadays as a result of variously contribution of climate change that cause by the anthropogenic effects. Global sea levels have been rising through the past century and are projected to rise at an accelerated rate throughout the 21st century. Due to this change, sea level is now constantly rising and eventually will threaten many low-lying and unprotected coastal areas in many ways. This paper is proposing a significant effort to quantify the sea level trend over Malaysian seas based on the combination of multi-mission satellite altimeters over a period of 23 years. Eight altimeter missions are used to derive the absolute sea level from Radar Altimeter Database System (RADS). Data verification is then carried out to verify the satellite derived sea level rise data with tidal data. Eight selected tide gauge stations from Peninsular Malaysia, Sabah and Sarawak are chosen for this data verification. The pattern and correlation of both measurements of sea level anomalies (SLA) are evaluated over the same period in each area in order to produce comparable results. Afterwards, the time series of the sea level trend is quantified using robust fit regression analysis. The findings clearly show that the absolute sea level trend is rising and varying over the Malaysian seas with the rate of sea level varies and gradually increase from east to west of Malaysia. Highly confident and correlation level of the 23 years measurement data with an astonishing root mean square difference permits the absolute sea level trend of the Malaysian seas has raised at the rate 3.14 ± 0.12 mm yr-1 to 4.81 ± 0.15 mm yr-1 for the chosen sub-areas, with an overall mean of 4.09 ± 0.12 mm yr-1. This study hopefully offers a beneficial sea level information to be applied in a wide range of related environmental and climatology issue such as flood and global warming.

  9. Satellite Altimeter Observations of Black Sea Level Variations

    NASA Technical Reports Server (NTRS)

    Korotaev, G. K.; Saenko, O. A.; Koblinsky, C. J.

    1998-01-01

    Satellite altimeter data from TOPEX/POSEIDON and ERS-1 are used to examine seasonal and mesoscale variability of the Black Sea level. Consistent processing procedures of the altimeter measurements make it possible to determine the dynamical Black Sea level with an rms accuracy about 3 cm. It is shown that the Black Sea circulation intensifies in the winter-spring seasons and attenuates in summer-autumn. The seasonal variability of sea level is accompanied by a radiation of Rossby waves from the eastern coast of the basin. Mesoscale oscillations of the dynamical sea level are found to vary spatially and temporarily. Usually, strong eddy intensity is associated with instabilities of the Rim Current. Away from this circulation feature, in the deep basin, mesoscale variability is much smaller. Mesoscale variability has a strong seasonal signal, which is out of phase with the strength of the Rim Current.

  10. Using Sea Level Change as a Climate Indicator

    NASA Astrophysics Data System (ADS)

    Masters, D. S.; Nerem, R. S.

    2014-12-01

    Sea level rise is one the more important risks due to climate change. Multiple satellite altimeters flying on the same repeating ground track have allowed estimation of global and regional sea level for the past 20 years, and the time series has yielded information about how sea level is responding to climate change. Due to the duration, consistency, and inter-calibration of the altimeter measurements, the time series is now considered a climate data record. The time series has also shown the strong dependence of sea level on interannual signals such as the ENSO and PDO. Global mean sea level change as estimated by the altimeters is arguably one of the most sensitive indicators of climate change because it varies almost entirely due to thermal expansion/contraction and the exchange of water between the land and oceans. Contributions to the latter include melting land ice and changes in the hydrologic cycle. While thermal expansion does not vary greatly on interannual time-scales, variations in the global hydrologic cycle and land ice melt can contribute to large variations in the sea level record. Isolating and understanding the causes and scales of these variations is important in interpreting the observed global and regional sea level change, especially for decision-makers assessing risk and planning for adaptation and/or mitigation. Since 1992, satellite altimeter measurements from the TOPEX/Poseidon and Jason missions, have been providing precise estimates of sea level change between ±66° latitude every 10 days. We have been using these measurements to monitor both global average and regional sea level change. The GRACE mission has provided monthly estimates of the time-varying gravity field for the last 10 years. These measurements can estimate variations in global ocean mass, mass changes in the polar ice sheets and mountain glaciers, as well as changes in the land surface water storage. These data sets can be used to inform us about the sea level change

  11. Regional Sea Level Scenarios for Coastal Risk Management: Managing the Uncertainty of Future Sea Level Change and Extreme Water Levels for Department of Defense Coastal Sites Worldwide

    DTIC Science & Technology

    2016-04-01

    SERDP NOAA USACE Ocean MANAGING THE UNCERTAINTY OF FUTURE SEA LEVEL CHANGE AND EXTREME WATER LEVELS FOR DEPARTMENT OF DEFENSE COASTAL SITES...Uncertainty of Future Sea Level Change and Extreme Water Levels for Department of Defense Coastal Sites Worldwide. U.S. Department of Defense...Strategic Environmental Research and Development Program. 224 pp. MANAGING THE UNCERTAINTY OF FUTURE SEA LEVEL CHANGE AND EXTREME WATER LEVELS FOR

  12. Global mapping of nonseismic sea level oscillations at tsunami timescales

    NASA Astrophysics Data System (ADS)

    Vilibić, Ivica; Šepić, Jadranka

    2017-01-01

    Present investigations of sea level extremes are based on hourly data measured at coastal tide gauges. The use of hourly data restricts existing global and regional analyses to periods larger than 2 h. However, a number of processes occur at minute timescales, of which the most ruinous are tsunamis. Meteotsunamis, hazardous nonseismic waves that occur at tsunami timescales over limited regions, may also locally dominate sea level extremes. Here, we show that nonseismic sea level oscillations at tsunami timescales (<2 h) may substantially contribute to global sea level extremes, up to 50% in low-tidal basins. The intensity of these oscillations is zonally correlated with mid-tropospheric winds at the 99% significance level, with the variance doubling from the tropics and subtropics to the mid-latitudes. Specific atmospheric patterns are found during strong events at selected locations in the World Ocean, indicating a globally predominant generation mechanism. Our analysis suggests that these oscillations should be considered in sea level hazard assessment studies. Establishing a strong correlation between nonseismic sea level oscillations at tsunami timescales and atmospheric synoptic patterns would allow for forecasting of nonseismic sea level oscillations for operational use, as well as hindcasting and projection of their effects under past, present and future climates.

  13. Global mapping of nonseismic sea level oscillations at tsunami timescales

    PubMed Central

    Vilibić, Ivica; Šepić, Jadranka

    2017-01-01

    Present investigations of sea level extremes are based on hourly data measured at coastal tide gauges. The use of hourly data restricts existing global and regional analyses to periods larger than 2 h. However, a number of processes occur at minute timescales, of which the most ruinous are tsunamis. Meteotsunamis, hazardous nonseismic waves that occur at tsunami timescales over limited regions, may also locally dominate sea level extremes. Here, we show that nonseismic sea level oscillations at tsunami timescales (<2 h) may substantially contribute to global sea level extremes, up to 50% in low-tidal basins. The intensity of these oscillations is zonally correlated with mid-tropospheric winds at the 99% significance level, with the variance doubling from the tropics and subtropics to the mid-latitudes. Specific atmospheric patterns are found during strong events at selected locations in the World Ocean, indicating a globally predominant generation mechanism. Our analysis suggests that these oscillations should be considered in sea level hazard assessment studies. Establishing a strong correlation between nonseismic sea level oscillations at tsunami timescales and atmospheric synoptic patterns would allow for forecasting of nonseismic sea level oscillations for operational use, as well as hindcasting and projection of their effects under past, present and future climates. PMID:28098195

  14. Global mapping of nonseismic sea level oscillations at tsunami timescales.

    PubMed

    Vilibić, Ivica; Šepić, Jadranka

    2017-01-18

    Present investigations of sea level extremes are based on hourly data measured at coastal tide gauges. The use of hourly data restricts existing global and regional analyses to periods larger than 2 h. However, a number of processes occur at minute timescales, of which the most ruinous are tsunamis. Meteotsunamis, hazardous nonseismic waves that occur at tsunami timescales over limited regions, may also locally dominate sea level extremes. Here, we show that nonseismic sea level oscillations at tsunami timescales (<2 h) may substantially contribute to global sea level extremes, up to 50% in low-tidal basins. The intensity of these oscillations is zonally correlated with mid-tropospheric winds at the 99% significance level, with the variance doubling from the tropics and subtropics to the mid-latitudes. Specific atmospheric patterns are found during strong events at selected locations in the World Ocean, indicating a globally predominant generation mechanism. Our analysis suggests that these oscillations should be considered in sea level hazard assessment studies. Establishing a strong correlation between nonseismic sea level oscillations at tsunami timescales and atmospheric synoptic patterns would allow for forecasting of nonseismic sea level oscillations for operational use, as well as hindcasting and projection of their effects under past, present and future climates.

  15. Some remarks on using the CMIP5 archive for sea-level projections

    NASA Astrophysics Data System (ADS)

    Jackson, L. P.; Jevrejeva, S.

    2014-12-01

    The observed regional patterns of sea-level change differ widely from the global average, which is partly due to ocean dynamics. This spatial variability has ramifications for the mitigation of future sea-level change because some coastal regions will be affected more strongly by sea-level rise than others. Quantitative projections of future sea-level rise rely on the outputs from climate models. The CMIP5 archive, which contains outputs from more than 60 climate models from 27 research groups, has been mined extensively for the purpose of sea-level projection based on four climate change scenarios. Previous studies show that regional patterns of sea-level change vary with each model. Not only that, but the individual model outputs vary widely in terms of actual resolution and model drift, and these factors have a secondary effect on the resulting projections. We explore the influence of model resolution and drift correction methods upon sea-level projections and consider the projections from a limited set of high resolution model outputs compared to a limited set of low resolution model outputs. Furthermore, we consider the implications for the ensemble mean error for the different sea-level related parameters from the coastline to the sea, and show that projections near the coastline are highly sensitive to the method used for projection calculation. This work contributes to the RISES-AM European Consortium Project, which seeks to provide a detailed holistic assessment of the physical and societal impacts of sea-level change due to high end climate change scenarios (>2°C warming relative to pre-industrial times).

  16. High-resolution tide projections reveal extinction threshold in response to sea-level rise.

    PubMed

    Field, Christopher R; Bayard, Trina S; Gjerdrum, Carina; Hill, Jason M; Meiman, Susan; Elphick, Chris S

    2017-05-01

    Sea-level rise will affect coastal species worldwide, but models that aim to predict these effects are typically based on simple measures of sea level that do not capture its inherent complexity, especially variation over timescales shorter than 1 year. Coastal species might be most affected, however, by floods that exceed a critical threshold. The frequency and duration of such floods may be more important to population dynamics than mean measures of sea level. In particular, the potential for changes in the frequency and duration of flooding events to result in nonlinear population responses or biological thresholds merits further research, but may require that models incorporate greater resolution in sea level than is typically used. We created population simulations for a threatened songbird, the saltmarsh sparrow (Ammodramus caudacutus), in a region where sea level is predictable with high accuracy and precision. We show that incorporating the timing of semidiurnal high tide events throughout the breeding season, including how this timing is affected by mean sea-level rise, predicts a reproductive threshold that is likely to cause a rapid demographic shift. This shift is likely to threaten the persistence of saltmarsh sparrows beyond 2060 and could cause extinction as soon as 2035. Neither extinction date nor the population trajectory was sensitive to the emissions scenarios underlying sea-level projections, as most of the population decline occurred before scenarios diverge. Our results suggest that the variation and complexity of climate-driven variables could be important for understanding the potential responses of coastal species to sea-level rise, especially for species that rely on coastal areas for reproduction.

  17. Synthetic stratigraphy of epicontinental seas: a carbonate sedimentation model and its applications in sea level studies

    SciTech Connect

    Cisne, J.L.; Gildner, R.F.

    1984-04-01

    Carbonates from the central parts of epicontinental seas are ideal strata for detailed study of eustatic sea level change. On the basis of sedimentation model in which carbonate accumulation rate is directly proportional to water depth, we developed synthetic stratigraphies for sea level histories expected for post-glacial transgression and for constant and sinusoidally fluctuating ocean ridge volume increase. These histories give distinctly different trends for water depth as a function of stratigraphic position in the sections' bathymetric curves. In general, water depth is proportional to the rate of sea level rise. Depth-dependent sedimentation leads to a time lag between sea level fluctuation and corresponding depth fluctuation which, as examples show, can approach 10/sup 6/ years for depth fluctuations of even a few meters--a fundamental consideration for reconstructing sea level curves, time-correlating sections by bathymetric curves, and relating water depth on continents to ocean ridge volume. Bathymetric curves based on gradient analysis of fossil assemblages (coenocorrelation curves) for American Middle Ordovician sections approximate patterns expected for sinusoidally increasing sea level. The model's predictions are tested in an ''artificial experiment'' that takes advantage of differential subsidence between the craton's middle and its edge to make a difference in the bathymetric histories of sections that otherwise record the same sea level history. The depth dependence in sedimentation was that above wave base net accumulation per year was very roughly 3 x 10/sup -6/ of the water depth.

  18. Sea Level Data Archaeology for the Global Sea Level Observing System (GLOSS)

    NASA Astrophysics Data System (ADS)

    Bradshaw, Elizabeth; Matthews, Andy; Rickards, Lesley; Jevrejeva, Svetlana

    2015-04-01

    The Global Sea Level Observing System (GLOSS) was set up in 1985 to collect long term tide gauge observations and has carried out a number of data archaeology activities over the past decade, including sending member organisations questionnaires to report on their repositories. The GLOSS Group of Experts (GLOSS GE) is looking to future developments in sea level data archaeology and will provide its user community with guidance on finding, digitising, quality controlling and distributing historic records. Many records may not be held in organisational archives and may instead by in national libraries, archives and other collections. GLOSS will promote a Citizen Science approach to discovering long term records by providing tools for volunteers to report data. Tide gauge data come in two different formats, charts and hand-written ledgers. Charts are paper analogue records generated by the mechanical instrument driving a pen trace. Several GLOSS members have developed software to automatically digitise these charts and the various methods were reported in a paper on automated techniques for the digitization of archived mareograms, delivered to the GLOSS GE 13th meeting. GLOSS is creating a repository of software for scanning analogue charts. NUNIEAU is the only publically available software for digitising tide gauge charts but other organisations have developed their own tide gauge digitising software that is available internally. There are several other freely available software packages that convert image data to numerical values. GLOSS could coordinate a comparison study of the various different digitising software programs by: Sending the same charts to each organisation and asking everyone to digitise them using their own procedures Comparing the digitised data Providing recommendations to the GLOSS community The other major form of analogue sea level data is handwritten ledgers, which are usually observations of high and low waters, but sometimes contain higher

  19. The Phanerozoic record of global sea-level change.

    PubMed

    Miller, Kenneth G; Kominz, Michelle A; Browning, James V; Wright, James D; Mountain, Gregory S; Katz, Miriam E; Sugarman, Peter J; Cramer, Benjamin S; Christie-Blick, Nicholas; Pekar, Stephen F

    2005-11-25

    We review Phanerozoic sea-level changes [543 million years ago (Ma) to the present] on various time scales and present a new sea-level record for the past 100 million years (My). Long-term sea level peaked at 100 +/- 50 meters during the Cretaceous, implying that ocean-crust production rates were much lower than previously inferred. Sea level mirrors oxygen isotope variations, reflecting ice-volume change on the 10(4)- to 10(6)-year scale, but a link between oxygen isotope and sea level on the 10(7)-year scale must be due to temperature changes that we attribute to tectonically controlled carbon dioxide variations. Sea-level change has influenced phytoplankton evolution, ocean chemistry, and the loci of carbonate, organic carbon, and siliciclastic sediment burial. Over the past 100 My, sea-level changes reflect global climate evolution from a time of ephemeral Antarctic ice sheets (100 to 33 Ma), through a time of large ice sheets primarily in Antarctica (33 to 2.5 Ma), to a world with large Antarctic and large, variable Northern Hemisphere ice sheets (2.5 Ma to the present).

  20. On the relationship between sea level and Spartina alterniflora production

    USGS Publications Warehouse

    Kirwan, Matthew L.; Christian, Robert R.; Blum, Linda K.; Brinson, Mark M.

    2012-01-01

    A positive relationship between interannual sea level and plant growth is thought to stabilize many coastal landforms responding to accelerating rates of sea level rise. Numerical models of delta growth, tidal channel network evolution, and ecosystem resilience incorporate a hump-shaped relationship between inundation and plant primary production, where vegetation growth increases with sea level up to an optimum water depth or inundation frequency. In contrast, we use decade-long measurements of Spartina alterniflora biomass in seven coastal Virginia (USA) marshes to demonstrate that interannual sea level is rarely a primary determinant of vegetation growth. Although we find tepid support for a hump-shaped relationship between aboveground production and inundation when marshes of different elevation are considered, our results suggest that marshes high in the intertidal zone and low in relief are unresponsive to sea level fluctuations. We suggest existing models are unable to capture the behavior of wetlands in these portions of the landscape, and may underestimate their vulnerability to sea level rise because sea level rise will not be accompanied by enhanced plant growth and resultant sediment accumulation.

  1. Sea level change: lessons from the geologic record

    USGS Publications Warehouse

    ,

    1995-01-01

    Rising sea level is potentially one of the most serious impacts of climatic change. Even a small sea level rise would have serious economic consequences because it would cause extensive damage to the world's coastal regions. Sea level can rise in the future because the ocean surface can expand due to warming and because polar ice sheets and mountain glaciers can melt, increasing the ocean's volume of water. Today, ice caps on Antarctica and Greenland contain 91 and 8 percent of the world's ice, respectively. The world's mountain glaciers together contain only about 1 percent. Melting all this ice would raise sea level about 80 meters. Although this extreme scenario is not expected, geologists know that sea level can rise and fall rapidly due to changing volume of ice on continents. For example, during the last ice age, about 18,000 years ago, continental ice sheets contained more than double the modem volume of ice. As ice sheets melted, sea level rose 2 to 3 meters per century, and possibly faster during certain times. During periods in which global climate was very warm, polar ice was reduced and sea level was higher than today.

  2. Upper Limit for Sea Level Projections by 2100

    NASA Astrophysics Data System (ADS)

    Jevrejeva, S.; Grinsted, A.; Moore, J. C.

    2014-12-01

    With more than 150 million people living within 1 m of high tide future sea level rise is one of the most damaging aspects of warming climate. The latest Intergovernmental Panel on Climate Change report (AR5 IPCC) noted that a 0.5 m rise in mean sea level will result in a dramatic increase the frequency of high water extremes - by an order of magnitude, or more in some regions. Thus the flood threat to the rapidly growing urban populations and associated infrastructure in coastal areas are major concerns for society. Hence, impact assessment, risk management, adaptation strategy and long-term decision making in coastal areas depend on projections of mean sea level and crucially its low probability, high impact, upper range. We construct the probability density function of global sea level at 2100, estimating that sea level rises larger than 180 cm are less than 5% probable. An upper limit for global sea level rise of 190 cm is assembled by summing the highest estimates of individual sea level rise components simulated by process based models with the RCP8.5 scenario. The agreement between the methods may suggest more confidence than is warranted since large uncertainties remain due to the lack of scenario-dependent projections from ice sheet dynamical models, particularly for mass loss from marine-based fast flowing outlet glaciers in Antarctica.

  3. Upper Limit for Sea Level Projections by 2100

    NASA Astrophysics Data System (ADS)

    Jevrejeva, Svetlana; Grinsted, Aslak; Moore, John

    2015-04-01

    With more than 150 million people living within 1 m of high tide future sea level rise is one of the most damaging aspects of warming climate. The latest Intergovernmental Panel on Climate Change report (AR5 IPCC) noted that a 0.5 m rise in mean sea level will result in a dramatic increase the frequency of high water extremes - by an order of magnitude, or more in some regions. Thus the flood threat to the rapidly growing urban populations and associated infrastructure in coastal areas are major concerns for society. Hence, impact assessment, risk management, adaptation strategy and long-term decision making in coastal areas depend on projections of mean sea level and crucially its low probability, high impact, upper range. We construct the probability density function of global sea level at 2100, estimating that sea level rises larger than 180 cm are less than 5% probable. An upper limit for global sea level rise of 190 cm is assembled by summing the highest estimates of individual sea level rise components simulated by process based models with the RCP8.5 scenario. The agreement between the methods may suggest more confidence than is warranted since large uncertainties remain due to the lack of scenario-dependent projections from ice sheet dynamical models, particularly for mass loss from marine-based fast flowing outlet glaciers in Antarctica.

  4. Subsidence and Relative Sea-level Rise in Threatened Deltas

    NASA Astrophysics Data System (ADS)

    Syvitski, J. P.; Higgins, S.

    2014-12-01

    In determining the risk lowland deltaic topography, as threatened by sea level rise and land subsidence, a number of important processes must be evaluated. Sea level rise is a global process but with local manifestations. Asian deltas have been experiencing higher rates of sea level rise due to the steric impact on dynamic (ocean) topography. Other large scale geophysical impacts on relative sea level at the local scale include the isostatic and flexural response to Holocene sea level history, Holocene sediment loads, and in former ice sheet zones --- glacial rebound. Tectonism does play a role on relative sea level rise, particularly in South America where the Eastern coastline, particularly Argentina, is rising relative to regional sea levels. Subsidence is impacted by both natural ground compaction, and accelerated compaction due to, for example, peat oxidation that often has a human driver (e.g. swamp reclammation). Subsidence is also impacted by the extraction of deeper deposits of petroleum and water. Rates of delta subsidence vary widely, depending on the magnitude of the anthropogenic driver, from a few mm/y to 100's of mm/y. Ground water withdrawal is the dominant reason behind much of the world's coastal subsidence, with important exceptions. On average subsidence rates (all causes) now contribute to local sea level innundations at rates four times faster then sea level is rising. New technologies, particularly InSAR and GPS methods, can often pin point the local cause (e.g. water withdrawl for agriculture versus for aquaculture). Subsurface soil or rock heterogeneity, and other very local geological patterns such as historical river pathways, also influence the temporal and spatial patterns associated with delta subsidence.

  5. Sea level trend and variability around Peninsular Malaysia

    NASA Astrophysics Data System (ADS)

    Luu, Q. H.; Tkalich, P.; Tay, T. W.

    2015-08-01

    Sea level rise due to climate change is non-uniform globally, necessitating regional estimates. Peninsular Malaysia is located in the middle of Southeast Asia, bounded from the west by the Malacca Strait, from the east by the South China Sea (SCS), and from the south by the Singapore Strait. The sea level along the peninsula may be influenced by various regional phenomena native to the adjacent parts of the Indian and Pacific oceans. To examine the variability and trend of sea level around the peninsula, tide gauge records and satellite altimetry are analyzed taking into account vertical land movements (VLMs). At annual scale, sea level anomalies (SLAs) around Peninsular Malaysia on the order of 5-25 cm are mainly monsoon driven. Sea levels at eastern and western coasts respond differently to the Asian monsoon: two peaks per year in the Malacca Strait due to South Asian-Indian monsoon; an annual cycle in the remaining region mostly due to the East Asian-western Pacific monsoon. At interannual scale, regional sea level variability in the range of ±6 cm is correlated with El Nino-Southern Oscillation (ENSO). SLAs in the Malacca Strait side are further correlated with the Indian Ocean Dipole (IOD) in the range of ±5 cm. Interannual regional sea level falls are associated with El Nino events and positive phases of IOD, whilst rises are correlated with La Nina episodes and negative values of the IOD index. At seasonal to interannual scales, we observe the separation of the sea level patterns in the Singapore Strait, between the Raffles Lighthouse and Tanjong Pagar tide stations, likely caused by a dynamic constriction in the narrowest part. During the observation period 1986-2013, average relative rates of sea level rise derived from tide gauges in Malacca Strait and along the east coast of the peninsula are 3.6±1.6 and 3.7±1.1 mm yr-1, respectively. Correcting for respective VLMs (0.8±2.6 and 0.9±2.2 mm yr-1), their corresponding geocentric sea level rise rates

  6. An alternative to reduction of surface pressure to sea level

    NASA Technical Reports Server (NTRS)

    Deardorff, J. W.

    1982-01-01

    The pitfalls of the present method of reducing surface pressure to sea level are reviewed, and an alternative, adjusted pressure, P, is proposed. P is obtained from solution of a Poisson equation over a continental region, using the simplest boundary condition along the perimeter or coastline where P equals the sea level pressure. The use of P would avoid the empiricisms and disadvantages of pressure reduction to sea level, and would produce surface pressure charts which depict the true geostrophic wind at the surface.

  7. Coastal Impact Underestimated From Rapid Sea Level Rise

    NASA Astrophysics Data System (ADS)

    Anderson, John; Milliken, Kristy; Wallace, Davin; Rodriguez, Antonio; Simms, Alexander

    2010-06-01

    A primary effect of global warming is accelerated sea level rise, which will eventually drown low-lying coastal areas, including some of the world's most populated cities. Predictions from the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) suggest that sea level may rise by as much as 0.6 meter by 2100 [Solomon et al., 2007]. However, uncertainty remains about how projected melting of the Greenland and Antarctic ice sheets will contribute to sea level rise. Further, considerable variability is introduced to these calculations due to coastal subsidence, especially along the northern Gulf of Mexico (see http://tidesandcurrents.noaa.gov/sltrends/sltrends.shtml).

  8. Explaining trends and variability in coastal relative sea level

    NASA Astrophysics Data System (ADS)

    Frederikse, Thomas; Riva, Riccardo

    2016-04-01

    Comprehensive understanding of trends and variability in coastal mean sea level is vital for protecting shores under a changing climate. To understand the behavior of coastal relative sea level (RSL), it is crucial to identify all relevant processes. We combine data from various geophysical models and observations to determine whether the trends and decadal variability observed in relative sea level at tide gauges can be explained by the sum of all known contributors. A key contributor to RSL is vertical land motion, which is caused by glacial isostatic adjustment (GIA), solid earth response to surface loading, tectonics, and local effects. We explicitly model low-frequency loading effects to correct GPS records, which leads to a more consistent trend than only using GIA models. Secondly, we create sea level fingerprints based on estimates of ice melt and changes in land hydrology, which provide the RSL contribution due to large-scale mass transport. Since coastal areas are often located on shallow continental shelves, steric effects will generally be small, and a large fraction of the decadal sea level variability will have a remote steric origin. Therefore, we determine a relation between coastal sea level and deep sea steric variability. For the period 1950-2012, we find that for many locations, including the European coast, the observed and modeled RSL time series agree well on decadal and secular scales.

  9. Sea-level variability over five glacial cycles.

    PubMed

    Grant, K M; Rohling, E J; Ramsey, C Bronk; Cheng, H; Edwards, R L; Florindo, F; Heslop, D; Marra, F; Roberts, A P; Tamisiea, M E; Williams, F

    2014-09-25

    Research on global ice-volume changes during Pleistocene glacial cycles is hindered by a lack of detailed sea-level records for time intervals older than the last interglacial. Here we present the first robustly dated, continuous and highly resolved records of Red Sea sea level and rates of sea-level change over the last 500,000 years, based on tight synchronization to an Asian monsoon record. We observe maximum 'natural' (pre-anthropogenic forcing) sea-level rise rates below 2 m per century following periods with up to twice present-day ice volumes, and substantially higher rise rates for greater ice volumes. We also find that maximum sea-level rise rates were attained within 2 kyr of the onset of deglaciations, for 85% of such events. Finally, multivariate regressions of orbital parameters, sea-level and monsoon records suggest that major meltwater pulses account for millennial-scale variability and insolation-lagged responses in Asian monsoon records.

  10. The sleep of elite athletes at sea level and high altitude: a comparison of sea-level natives and high-altitude natives (ISA3600)

    PubMed Central

    Roach, Gregory D; Schmidt, Walter F; Aughey, Robert J; Bourdon, Pitre C; Soria, Rudy; Claros, Jesus C Jimenez; Garvican-Lewis, Laura A; Buchheit, Martin; Simpson, Ben M; Hammond, Kristal; Kley, Marlen; Wachsmuth, Nadine; Gore, Christopher J; Sargent, Charli

    2013-01-01

    Background Altitude exposure causes acute sleep disruption in non-athletes, but little is known about its effects in elite athletes. The aim of this study was to examine the effects of altitude on two groups of elite athletes, that is, sea-level natives and high-altitude natives. Methods Sea-level natives were members of the Australian under-17 soccer team (n=14). High-altitude natives were members of a Bolivian under-20 club team (n=12). Teams participated in an 18-day (19 nights) training camp in Bolivia, with 6 nights at near sea level in Santa Cruz (430 m) and 13 nights at high altitude in La Paz (3600 m). Sleep was assessed on every day/night using activity monitors. Results The Australians’ sleep was shorter, and of poorer quality, on the first night at altitude compared with sea level. Sleep quality returned to normal by the end of the first week at altitude, but sleep quantity had still not stabilised at its normal level after 2 weeks. The quantity and quality of sleep obtained by the Bolivians was similar, or greater, on all nights at altitude compared with sea level. The Australians tended to obtain more sleep than the Bolivians at sea level and altitude, but the quality of the Bolivians’ sleep tended to be better than that of the Australians at altitude. Conclusions Exposure to high altitude causes acute and chronic disruption to the sleep of elite athletes who are sea-level natives, but it does not affect the sleep of elite athletes who are high-altitude natives. PMID:24282197

  11. Sea water intrusion by sea-level rise: scenarios for the 21st century.

    PubMed

    Loáiciga, Hugo A; Pingel, Thomas J; Garcia, Elizabeth S

    2012-01-01

    This study presents a method to assess the contributions of 21st-century sea-level rise and groundwater extraction to sea water intrusion in coastal aquifers. Sea water intrusion is represented by the landward advance of the 10,000 mg/L iso-salinity line, a concentration of dissolved salts that renders groundwater unsuitable for human use. A mathematical formulation of the resolution of sea water intrusion among its causes was quantified via numerical simulation under scenarios of change in groundwater extraction and sea-level rise in the 21st century. The developed method is illustrated with simulations of sea water intrusion in the Seaside Area sub-basin near the City of Monterey, California (USA), where predictions of mean sea-level rise through the early 21st century range from 0.10 to 0.90 m due to increasing global mean surface temperature. The modeling simulation was carried out with a state-of-the-art numerical model that accounts for the effects of salinity on groundwater density and can approximate hydrostratigraphic geometry closely. Simulations of sea water intrusion corresponding to various combinations of groundwater extraction and sea-level rise established that groundwater extraction is the predominant driver of sea water intrusion in the study aquifer. The method presented in this work is applicable to coastal aquifers under a variety of other scenarios of change not considered in this work. For example, one could resolve what changes in groundwater extraction and/or sea level would cause specified levels of groundwater salinization at strategic locations and times.

  12. Developing a Coastal Risk Indicator for Sea Level Rise

    NASA Astrophysics Data System (ADS)

    Masters, D. S.; Nerem, R.

    2012-12-01

    Coastal sea level rise is one the most important potential environmental risks. Multiple satellite altimeters flying on the same repeat orbit track have allowed estimation of global mean sea level for the past 20 years, and the time series has yielded information about the average rate of sea level increase over that time. Due to the duration, consistency, and inter-calibration of the altimeter measurements, the time series is now considered a climate record. The time series has also shown the strong dependence of sea level on interannual signals such as the ENSO and the NAO. But the most important sea level effects of climate change will be felt on the regional and local scales. At these smaller scales, local effects due to topography, tides, earth deformation (glacial isostatic adjustment (GIA), subsidence, etc.), and storm surges must also be considered when estimating the risks of sea level change to coastal communities. Recently, work has begun to understand the methods applicable to estimating the risks of expected sea level change to coastal communities (Strauss et al., 2012; Tebaldi et al., 2012). Tebaldi et al (2012) merged the expected global mean sea level increase from the semi-empirical model of Vermeer and Rahmstorf (2009) with historical local tide gauges to predict increases in storm surge risk posed by increasing sea level. In this work, we will further explore the currently available data and tools that can potentially be used to provide a sea level climate change indicator and local risk assessment along US coasts. These include global and regional sea level trends from the satellite altimetry climate record, in situ tide gauge measurements and the historical extremes at each location, local tide and storm surge models, topographic surveys of vulnerable coastlines, GIA models, and measurements of local subsidence and crustal deformation rates. We will also evaluate methods to estimate the increased risk to communities from sea level change

  13. Modeling landscape dynamics and effects of sea-level rise on coastal wetlands of northwest Florida

    SciTech Connect

    Doyle, T.W.; Day, R.H.; Biagas, J.M.

    1997-06-01

    A research study to examine the ability to predict changes in coastal vegetation caused by sea level rise is very briefly summarized. A field survey was carried out on the northwest coast of Florida. A predictive elevation model was then generated from digitized US Geologic Survey 1:2400 hypsographic data using surface modeling techniques. Sea-level rise model simulations were generated to predict a likelihood index of habitat change and conversions under different scenarios. Maps were produced depicting location of the coastline and inland extent of salt marsh using a range of sea level rise rates through the year 2100. This modeling approach offers a technological tool to researchers and wetland managers for effective cumulative impact analysis of wetlands affected by sea-level rise.

  14. The multimillennial sea-level commitment of global warming.

    PubMed

    Levermann, Anders; Clark, Peter U; Marzeion, Ben; Milne, Glenn A; Pollard, David; Radic, Valentina; Robinson, Alexander

    2013-08-20

    Global mean sea level has been steadily rising over the last century, is projected to increase by the end of this century, and will continue to rise beyond the year 2100 unless the current global mean temperature trend is reversed. Inertia in the climate and global carbon system, however, causes the global mean temperature to decline slowly even after greenhouse gas emissions have ceased, raising the question of how much sea-level commitment is expected for different levels of global mean temperature increase above preindustrial levels. Although sea-level rise over the last century has been dominated by ocean warming and loss of glaciers, the sensitivity suggested from records of past sea levels indicates important contributions should also be expected from the Greenland and Antarctic Ice Sheets. Uncertainties in the paleo-reconstructions, however, necessitate additional strategies to better constrain the sea-level commitment. Here we combine paleo-evidence with simulations from physical models to estimate the future sea-level commitment on a multimillennial time scale and compute associated regional sea-level patterns. Oceanic thermal expansion and the Antarctic Ice Sheet contribute quasi-linearly, with 0.4 m °C(-1) and 1.2 m °C(-1) of warming, respectively. The saturation of the contribution from glaciers is overcompensated by the nonlinear response of the Greenland Ice Sheet. As a consequence we are committed to a sea-level rise of approximately 2.3 m °C(-1) within the next 2,000 y. Considering the lifetime of anthropogenic greenhouse gases, this imposes the need for fundamental adaptation strategies on multicentennial time scales.

  15. Climate And Sea Level: It's In Our Hands Now

    NASA Astrophysics Data System (ADS)

    Turrin, M.; Bell, R. E.; Ryan, W. B. F.

    2014-12-01

    Changes in sea level are measurable on both a local and a global scale providing an accessible way to connect climate to education, yet engaging teachers and students with the complex science that is behind the change in sea level can be a challenge. Deciding how much should be included and just how it should be introduced in any single classroom subject area can be an obstacle for a teacher. The Sea Level Rise Polar Explorer App developed through the PoLAR CCEP grant offers a guided tour through the many layers of science that impact sea level rise. This map-based data-rich app is framed around a series of questions that move the user through map layers with just the level of complexity they chose to explore. For a quick look teachers and students can review a 3 or 4 sentence introduction on how the given map links to sea level and then launch straight into the interactive touchable map. For a little more in depth look they can listen to (or read) a one-minute recorded background on the data displayed in the map prior to launching in. For those who want more in depth understanding they can click to a one page background piece on the topic with links to further visualizations, videos and data. Regardless of the level of complexity selected each map is composed of clickable data allowing the user to fully explore the science. The different options for diving in allow teachers to differentiate the learning for either the subject being taught or the user level of the student group. The map layers also include a range of complexities. Basic questions like "What is sea level?" talk about shorelines, past sea levels and elevations beneath the sea. Questions like "Why does sea level change?" includes slightly more complex issues like the role of ocean temperature, and how that differs from ocean heat content. And what is the role of the warming atmosphere in sea level change? Questions about "What about sea level in the past?" can bring challenges for students who have

  16. Global Projection of Coastal Exposure Associated with Sea-level Rise beyond Tipping Points

    NASA Astrophysics Data System (ADS)

    Tawatari, R.; Miyazaki, C.; Iseri, Y.; Kiguchi, M.; Kanae, S.

    2015-12-01

    Sea-level rise due to global warming becomes a great matter of concern for global coastal area. Additionally, it has reported in fifth report of IPCC (Intergovernmental Panel on Climate Change) that deglaciation of Greenland ice sheet and Antarctic ice sheet would occur rapidly and enhance sea-level rise if temperature passes certain "Tipping point". In terms of projecting damage induced by sea-level rise globally, some previous studies focused on duration until mainly 2100. Furthermore long-term estimations on centuries to millennial climatic response of the ice sheets which are supposed to be triggered within this or next century would be also important to think about future climate and lifestyle in coastal . In this study, I estimated the long term sea-level which take into account the tipping points of Greenland ice sheet (1.4℃) as sum of 4 factors (thermal expansion, glacier and ice cap, Greenland ice sheet, Antarctic ice sheet). The sea-level follows 4 representative concentration pathways up to 3000 obtained through literature reviewing since there were limited available sea-level projections up to 3000. I also estimated a number of affected population lives in coastal area up to 3000 with using the estimated sea-level. The cost for damage, adaptation and mitigation would be also discussed. These estimations would be useful when decision-makers propose policies for construction of dikes and proposing mitigation plans for sustainable future. The result indicates there would be large and relatively rapid increases in both sea-level rise and coastal exposure if global mean temperature passes the tipping point of Greenland ice sheet. However the tipping points, melting rate and timescale of response are highly uncertain and still discussed among experts. Thus more precise and credible information is required for further accurate estimation of long-term sea-level rise and population exposure in the future.

  17. Hazard Risk to Near Sea-Level Populations due to Tropical Cyclone Intensification and Sea-Level Rise

    NASA Astrophysics Data System (ADS)

    Montain, J.; Byrne, J. M.; Elsner, J.

    2010-12-01

    Tropical cyclone (TC) intensification has been well documented in the science literature. TC intensification combined with sea-level rise contributes to an enhanced risk to huge populations living near sea level around the world. This study will apply spatial analysis techniques to combine the best available TC intensification data on storm surge, wave height and wind speeds; with digital elevation models and global population density estimates, to provide a first level evaluation of the increasing risk to human life and health.

  18. The anatomy of recent large sea level fluctuations in the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Landerer, Felix W.; Volkov, Denis L.

    2013-02-01

    Abstract During the boreal winter months of 2009/2010 and 2010/2011, Mediterranean mean <span class="hlt">sea</span> <span class="hlt">level</span> rose 10 cm above the average monthly climatological values. The non-seasonal anomalies were observed in <span class="hlt">sea</span> surface height (from altimetry), as well as ocean mass (from gravimetry), indicating they were mostly of barotropic nature. These relatively rapid basin-wide fluctuations occurred over time scales of 1-5 months. Here we use observations and re-analysis data to attribute the non-seasonal <span class="hlt">sea</span> <span class="hlt">level</span> and ocean mass fluctuations in the Mediterranean <span class="hlt">Sea</span> to concurrent wind stress anomalies over the adjacent subtropical Northeast Atlantic Ocean, just west of the Strait of Gibraltar, and extending into the strait itself. The observed Mediterranean <span class="hlt">sea</span> <span class="hlt">level</span> fluctuations are strongly anti-correlated with the monthly North-Atlantic-Oscillation (NAO) index.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70121488','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70121488"><span>Potential effects of <span class="hlt">sea-level</span> rise on coastal wetlands in southeastern Louisiana</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Glick, Patty; Clough, Jonathan; Polaczyk, Amy; Couvillion, Brady R.; Nunley, Brad</p> <p>2013-01-01</p> <p>Coastal Louisiana wetlands contain about 37% of the estuarine herbaceous marshes in the conterminous United States. The long-term stability of coastal wetlands is often a function of a wetland's ability to maintain elevation equilibrium with mean <span class="hlt">sea</span> <span class="hlt">level</span> through processes such as primary production and sediment accretion. However, Louisiana has sustained more coastal wetland loss than all other states in the continental United States combined due to a combination of natural and anthropogenic factors, including <span class="hlt">sea-level</span> rise. This study investigates the potential impact of current and accelerating <span class="hlt">sea-level</span> rise rates on key coastal wetland habitats in southeastern Louisiana using the <span class="hlt">Sea</span> <span class="hlt">Level</span> <span class="hlt">Affecting</span> Marshes Model (SLAMM). Model calibration was conducted using a 1956–2007 observation period and hindcasting results predicted 35% versus observed 39% total marsh loss. Multiple <span class="hlt">sea-level</span>-rise scenarios were then simulated for the period of 2007–2100. Results indicate a range of potential wetland losses by 2100, from an additional 2,188.97 km2 (218,897 ha, 9% of the 2007 wetland area) under the lowest <span class="hlt">sea-level</span>-rise scenario (0.34 m), to a potential loss of 5,875.27 km2 (587,527 ha, 24% of the 2007 wetland area) in the highest <span class="hlt">sea-level</span>-rise scenario (1.9 m). Model results suggest that one area of particular concern is the potential vulnerability of the region's baldcypress-water tupelo (Taxodium distichum-Nyssa aquatica) swamp habitat, much of which is projected to become permanently flooded (<span class="hlt">affecting</span> regeneration) under all modeled scenarios for <span class="hlt">sea-level</span> rise. These findings will aid in the development of ecosystem management plans that support the processes and conditions that result in sustainable coastal ecosystems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1710077E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1710077E"><span>Characterization of extreme <span class="hlt">sea</span> <span class="hlt">level</span> at the European coast</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Elizalde, Alberto; Jorda, Gabriel; Mathis, Moritz; Mikolajewicz, Uwe</p> <p>2015-04-01</p> <p>Extreme high <span class="hlt">sea</span> <span class="hlt">levels</span> arise as a combination of storm surges and particular high tides events. Future climate simulations not only project changes in the atmospheric circulation, which induces changes in the wind conditions, but also an increase in the global mean <span class="hlt">sea</span> <span class="hlt">level</span> by thermal expansion and ice melting. Such changes increase the risk of coastal flooding, which represents a possible hazard for human activities. Therefore, it is important to investigate the pattern of <span class="hlt">sea</span> <span class="hlt">level</span> variability and long-term trends at coastal areas. In order to analyze further extreme <span class="hlt">sea</span> <span class="hlt">level</span> events at the European coast in the future climate projections, a new setup for the global ocean model MPIOM coupled with the regional atmosphere model REMO is prepared. The MPIOM irregular grid has enhanced resolution in the European region to resolve the North and the Mediterranean <span class="hlt">Seas</span> (up to 11 x 11 km at the North <span class="hlt">Sea</span>). The ocean model includes as well the full luni-solar ephemeridic tidal potential for tides simulation. To simulate the air-<span class="hlt">sea</span> interaction, the regional atmospheric model REMO is interactively coupled to the ocean model over Europe. Such region corresponds to the EuroCORDEX domain with a 50 x 50 km resolution. Besides the standard fluxes of heat, mass (freshwater), momentum and turbulent energy input, the ocean model is also forced with <span class="hlt">sea</span> <span class="hlt">level</span> pressure, in order to be able to capture the full variation of <span class="hlt">sea</span> <span class="hlt">level</span>. The hydrological budget within the study domain is closed using a hydrological discharge model. With this model, simulations for present climate and future climate scenarios are carried out to study transient changes on the <span class="hlt">sea</span> <span class="hlt">level</span> and extreme events. As a first step, two simulations (coupled and uncoupled ocean) driven by reanalysis data (ERA40) have been conducted. They are used as reference runs to evaluate the climate projection simulations. For selected locations at the coast side, time series of <span class="hlt">sea</span> <span class="hlt">level</span> are separated on its different</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatCC...6..253K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatCC...6..253K"><span>Overestimation of marsh vulnerability to <span class="hlt">sea</span> <span class="hlt">level</span> rise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kirwan, Matthew L.; Temmerman, Stijn; Skeehan, Emily E.; Guntenspergen, Glenn R.; Fagherazzi, Sergio</p> <p>2016-03-01</p> <p>Coastal marshes are considered to be among the most valuable and vulnerable ecosystems on Earth, where the imminent loss of ecosystem services is a feared consequence of <span class="hlt">sea</span> <span class="hlt">level</span> rise. However, we show with a meta-analysis that global measurements of marsh elevation change indicate that marshes are generally building at rates similar to or exceeding historical <span class="hlt">sea</span> <span class="hlt">level</span> rise, and that process-based models predict survival under a wide range of future <span class="hlt">sea</span> <span class="hlt">level</span> scenarios. We argue that marsh vulnerability tends to be overstated because assessment methods often fail to consider biophysical feedback processes known to accelerate soil building with <span class="hlt">sea</span> <span class="hlt">level</span> rise, and the potential for marshes to migrate inland.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Natur.532...42F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Natur.532...42F"><span>Island biogeography: Shaped by <span class="hlt">sea-level</span> shifts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fernández-Palacios, José María</p> <p>2016-04-01</p> <p>An analysis of changes in island topography and climate that have occurred since the last glacial maximum 21,000 years ago shows how <span class="hlt">sea-level</span> change has influenced the current biodiversity of oceanic islands. See Letter p.99</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GeoRL..42.6747M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GeoRL..42.6747M"><span>Seasonal coastal <span class="hlt">sea</span> <span class="hlt">level</span> prediction using a dynamical model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McIntosh, Peter C.; Church, John A.; Miles, Elaine R.; Ridgway, Ken; Spillman, Claire M.</p> <p>2015-08-01</p> <p><span class="hlt">Sea</span> <span class="hlt">level</span> varies on a range of time scales from tidal to decadal and centennial change. To date, little attention has been focussed on the prediction of interannual <span class="hlt">sea</span> <span class="hlt">level</span> anomalies. Here we demonstrate that forecasts of coastal <span class="hlt">sea</span> <span class="hlt">level</span> anomalies from the dynamical Predictive Ocean Atmosphere Model for Australia (POAMA) have significant skill throughout the equatorial Pacific and along the eastern boundaries of the Pacific and Indian Oceans at lead times out to 8 months. POAMA forecasts for the western Pacific generally have greater skill than persistence, particularly at longer lead times. POAMA also has comparable or greater skill than previously published statistical forecasts from both a Markov model and canonical correlation analysis. Our results indicate the capability of physically based models to address the challenge of providing skillful forecasts of seasonal <span class="hlt">sea</span> <span class="hlt">level</span> fluctuations for coastal communities over a broad area and at a range of lead times.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.youtube.com/watch?v=7l7BY2B3jSU','SCIGOVIMAGE-NASA'); return false;" href="http://www.youtube.com/watch?v=7l7BY2B3jSU"><span>Twenty-two Years of <span class="hlt">Sea</span> <span class="hlt">Level</span> Rise</span></a></p> <p><a target="_blank" href="http://www.nasa.gov/multimedia/videogallery/index.html">NASA Video Gallery</a></p> <p></p> <p></p> <p>This visualization shows total <span class="hlt">sea</span> <span class="hlt">level</span> change between the beginning of 1993 and the end of 2014, based on data collected from the TOPEX/Poisedon, Jason-1, and Jason-2 satellites. Blue regions are...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70169064','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70169064"><span>Overestimation of marsh vulnerability to <span class="hlt">sea</span> <span class="hlt">level</span> rise</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Kirwan, Matthew L.; Temmerman, Stijn; Skeehan, Emily E.; Guntenspergen, Glenn R.; Fagherazzi, Sergio</p> <p>2016-01-01</p> <p>Coastal marshes are considered to be among the most valuable and vulnerable ecosystems on Earth, where the imminent loss of ecosystem services is a feared consequence of <span class="hlt">sea</span> <span class="hlt">level</span> rise. However, we show with a meta-analysis that global measurements of marsh elevation change indicate that marshes are generally building at rates similar to or exceeding historical <span class="hlt">sea</span> <span class="hlt">level</span> rise, and that process-based models predict survival under a wide range of future <span class="hlt">sea</span> <span class="hlt">level</span> scenarios. We argue that marsh vulnerability tends to be overstated because assessment methods often fail to consider biophysical feedback processes known to accelerate soil building with <span class="hlt">sea</span> <span class="hlt">level</span> rise, and the potential for marshes to migrate inland.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6784832','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6784832"><span>Chronology of fluctuating <span class="hlt">sea</span> <span class="hlt">levels</span> since the triassic</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Haq, B.U.; Hardenbol, J.; Vail, P.R.</p> <p>1987-03-06</p> <p>Advances in sequence stratigraphy and the development of depositional models have helped explain the origin of genetically related sedimentary packages during <span class="hlt">sea</span> <span class="hlt">level</span> cycles. These concepts have provided the basis for the recognition of <span class="hlt">sea</span> <span class="hlt">level</span> events in subsurface data and in outcrops of marine sediments around the world. Knowledge of these events has led to a new generation of Mesozoic and Cenozoic global cycle charts that chronicle the history of <span class="hlt">sea</span> <span class="hlt">level</span> fluctuations during the past 250 million years in greater detail than was possible from seismic-stratigraphic data alone. An effort has been made to develop a realistic and accurate time scale and widely applicable chronostratigraphy and to integrate depositional sequences documented in public domain outcrop sections from various basins with this chronostratigraphic framework. A description of this approach and an account of the results, illustrated by <span class="hlt">sea</span> <span class="hlt">level</span> cycle charts of the Cenozoic, Cretaceous, Jurassic, and Triassic intervals, are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70121272','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70121272"><span>[Book review] <span class="hlt">Sea</span> <span class="hlt">level</span> rise: history and consequences</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Grossman, Eric E.</p> <p>2004-01-01</p> <p>Review of: <span class="hlt">Sea</span> <span class="hlt">level</span> Rise: history and consequences. Bruce Douglas, Michael S. Kearney and Stephen P. Leatherman (eds), Sand Diego: Academic Press, 2001, 232 pp. plus CD-RIM, US$64.95, hardback. ISBN 0-12-221345-9.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26160951','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26160951"><span><span class="hlt">SEA-LEVEL</span> RISE. <span class="hlt">Sea-level</span> rise due to polar ice-sheet mass loss during past warm periods.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dutton, A; Carlson, A E; Long, A J; Milne, G A; Clark, P U; DeConto, R; Horton, B P; Rahmstorf, S; Raymo, M E</p> <p>2015-07-10</p> <p>Interdisciplinary studies of geologic archives have ushered in a new era of deciphering magnitudes, rates, and sources of <span class="hlt">sea-level</span> rise from polar ice-sheet loss during past warm periods. Accounting for glacial isostatic processes helps to reconcile spatial variability in peak <span class="hlt">sea</span> <span class="hlt">level</span> during marine isotope stages 5e and 11, when the global mean reached 6 to 9 meters and 6 to 13 meters higher than present, respectively. Dynamic topography introduces large uncertainties on longer time scales, precluding robust <span class="hlt">sea-level</span> estimates for intervals such as the Pliocene. Present climate is warming to a <span class="hlt">level</span> associated with significant polar ice-sheet loss in the past. Here, we outline advances and challenges involved in constraining ice-sheet sensitivity to climate change with use of paleo-<span class="hlt">sea</span> <span class="hlt">level</span> records.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870033250&hterms=sea+level+change&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dsea%2Blevel%2Bchange','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870033250&hterms=sea+level+change&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dsea%2Blevel%2Bchange"><span>Accurate measurement of mean <span class="hlt">sea</span> <span class="hlt">level</span> changes by altimetric satellites</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Born, G. H.; Tapley, B. D.; Ries, J. C.; Stewart, R. H.</p> <p>1986-01-01</p> <p>A technique for monitoring changes in global mean <span class="hlt">sea</span> <span class="hlt">levels</span> using altimeter data from a well-tracked satellite is examined. The usefulness of this technique is evaluated by analyzing Seasat altimeter data obtained during July-September 1978. The effects of orbit errors, geoid errors, sampling intervals, tides, and atmosphere refraction on the calculation of the mean <span class="hlt">sea</span> <span class="hlt">level</span> are investigated. The data reveal that the stability of an altimeter can be determined with an accuracy of + or - 7 cm using globally averaged <span class="hlt">sea</span> surface height measurements. The application of this procedure to the US/French Ocean Topography Experiment is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920037309&hterms=Sargasso+Sea&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DSargasso%2BSea','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920037309&hterms=Sargasso+Sea&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DSargasso%2BSea"><span><span class="hlt">Sea</span> <span class="hlt">level</span> differences across the Gulf Stream and Kuroshio extension</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zlotnicki, Victor</p> <p>1991-01-01</p> <p>The <span class="hlt">sea</span> <span class="hlt">level</span> differences between the Sargasso <span class="hlt">Sea</span> and the slope waters across the Gulf Stream region, averaged between 73 and 61 deg W, and the comparable areas across the Kuroshio extension region, averaged between 143 and 156 deg E, were estimated using the Geosat altimeter data obtained between November 1986 and December 1988. The <span class="hlt">sea-level</span> differences between the two regions showed a strong correlation between the northwest Atlantic and Pacific, dominated by annual cycles that peak in late-September to mid-October, with about 9 cm (the Gulf Stream region) and about 6.9 cm (Kuroshio region) amplitudes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11679657','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11679657"><span>Climate change. How fast are <span class="hlt">sea</span> <span class="hlt">levels</span> rising?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Church, J A</p> <p>2001-10-26</p> <p><span class="hlt">Sea</span> <span class="hlt">levels</span> are rising as a result of global warming, but assessing the rate of the rise is proving difficult. In his Perspective, Church highlights the report by Cabanes et al., who have reassessed observational data and find that it is closer to model estimates than previously found. However, observational data are still limited and models disagree in their regional projections. With present data and models, regional <span class="hlt">sea-level</span> changes cannot be predicted with confidence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AIPC.1157...19P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AIPC.1157...19P"><span>Adapting to Rising <span class="hlt">Sea</span> <span class="hlt">Level</span>: A Florida Perspective</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Parkinson, Randall W.</p> <p>2009-07-01</p> <p>Global climate change and concomitant rising <span class="hlt">sea</span> <span class="hlt">level</span> will have a profound impact on Florida's coastal and marine systems. <span class="hlt">Sea-level</span> rise will increase erosion of beaches, cause saltwater intrusion into water supplies, inundate coastal marshes and other important habitats, and make coastal property more vulnerable to erosion and flooding. Yet most coastal areas are currently managed under the premise that <span class="hlt">sea-level</span> rise is not significant and the shorelines are static or can be fixed in place by engineering structures. The new reality of <span class="hlt">sea-level</span> rise and extreme weather due to climate change requires a new style of planning and management to protect resources and reduce risk to humans. Scientists must: (1) assess existing coastal vulnerability to address short term management issues and (2) model future landscape change and develop sustainable plans to address long term planning and management issues. Furthermore, this information must be effectively transferred to planners, managers, and elected officials to ensure their decisions are based upon the best available information. While there is still some uncertainty regarding the details of rising <span class="hlt">sea</span> <span class="hlt">level</span> and climate change, development decisions are being made today which commit public and private investment in real estate and associated infrastructure. With a design life of 30 yrs to 75 yrs or more, many of these investments are on a collision course with rising <span class="hlt">sea</span> <span class="hlt">level</span> and the resulting impacts will be significant. In the near term, the utilization of engineering structures may be required, but these are not sustainable and must ultimately yield to "managed withdrawal" programs if higher <span class="hlt">sea-level</span> elevations or rates of rise are forthcoming. As an initial step towards successful adaptation, coastal management and planning documents (i.e., comprehensive plans) must be revised to include reference to climate change and rising <span class="hlt">sea-level</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70039314','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70039314"><span>Population dynamics of Hawaiian seabird colonies vulnerable to <span class="hlt">sea-level</span> rise</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hatfield, Jeff S.; Reynolds, Michelle H.; Seavy, Nathaniel E.; Krause, Crystal M.</p> <p>2012-01-01</p> <p>Globally, seabirds are vulnerable to anthropogenic threats both at <span class="hlt">sea</span> and on land. Seabirds typically nest colonially and show strong fidelity to natal colonies, and such colonies on low-lying islands may be threatened by <span class="hlt">sea-level</span> rise. We used French Frigate Shoals, the largest atoll in the Hawaiian Archipelago, as a case study to explore the population dynamics of seabird colonies and the potential effects <span class="hlt">sea-level</span> rise may have on these rookeries. We compiled historic observations, a 30-year time series of seabird population abundance, lidar-derived elevations, and aerial imagery of all the islands of French Frigate Shoals. To estimate the population dynamics of 8 species of breeding seabirds on Tern Island from 1980 to 2009, we used a Gompertz model with a Bayesian approach to infer population growth rates, density dependence, process variation, and observation error. All species increased in abundance, in a pattern that provided evidence of density dependence. Great Frigatebirds (Fregata minor), Masked Boobies (Sula dactylatra), Red-tailed Tropicbirds (Phaethon rubricauda), Spectacled Terns (Onychoprion lunatus), and White Terns (Gygis alba) are likely at carrying capacity. Density dependence may exacerbate the effects of <span class="hlt">sea-level</span> rise on seabirds because populations near carrying capacity on an island will be more negatively <span class="hlt">affected</span> than populations with room for growth. We projected 12% of French Frigate Shoals will be inundated if <span class="hlt">sea</span> <span class="hlt">level</span> rises 1 m and 28% if <span class="hlt">sea</span> <span class="hlt">level</span> rises 2 m. Spectacled Terns and shrub-nesting species are especially vulnerable to <span class="hlt">sea-level</span> rise, but seawalls and habitat restoration may mitigate the effects of <span class="hlt">sea-level</span> rise. Losses of seabird nesting habitat may be substantial in the Hawaiian Islands by 2100 if <span class="hlt">sea</span> <span class="hlt">levels</span> rise 2 m. Restoration of higher-elevation seabird colonies represent a more enduring conservation solution for Pacific seabirds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22624702','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22624702"><span>Population dynamics of Hawaiian seabird colonies vulnerable to <span class="hlt">sea-level</span> rise.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hatfield, Jeff S; Reynolds, Michelle H; Seavy, Nathaniel E; Krause, Crystal M</p> <p>2012-08-01</p> <p>Globally, seabirds are vulnerable to anthropogenic threats both at <span class="hlt">sea</span> and on land. Seabirds typically nest colonially and show strong fidelity to natal colonies, and such colonies on low-lying islands may be threatened by <span class="hlt">sea-level</span> rise. We used French Frigate Shoals, the largest atoll in the Hawaiian Archipelago, as a case study to explore the population dynamics of seabird colonies and the potential effects <span class="hlt">sea-level</span> rise may have on these rookeries. We compiled historic observations, a 30-year time series of seabird population abundance, lidar-derived elevations, and aerial imagery of all the islands of French Frigate Shoals. To estimate the population dynamics of 8 species of breeding seabirds on Tern Island from 1980 to 2009, we used a Gompertz model with a Bayesian approach to infer population growth rates, density dependence, process variation, and observation error. All species increased in abundance, in a pattern that provided evidence of density dependence. Great Frigatebirds (Fregata minor), Masked Boobies (Sula dactylatra), Red-tailed Tropicbirds (Phaethon rubricauda), Spectacled Terns (Onychoprion lunatus), and White Terns (Gygis alba) are likely at carrying capacity. Density dependence may exacerbate the effects of <span class="hlt">sea-level</span> rise on seabirds because populations near carrying capacity on an island will be more negatively <span class="hlt">affected</span> than populations with room for growth. We projected 12% of French Frigate Shoals will be inundated if <span class="hlt">sea</span> <span class="hlt">level</span> rises 1 m and 28% if <span class="hlt">sea</span> <span class="hlt">level</span> rises 2 m. Spectacled Terns and shrub-nesting species are especially vulnerable to <span class="hlt">sea-level</span> rise, but seawalls and habitat restoration may mitigate the effects of <span class="hlt">sea-level</span> rise. Losses of seabird nesting habitat may be substantial in the Hawaiian Islands by 2100 if <span class="hlt">sea</span> <span class="hlt">levels</span> rise 2 m. Restoration of higher-elevation seabird colonies represent a more enduring conservation solution for Pacific seabirds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23504873','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23504873"><span>Tidal marsh plant responses to elevated CO2 , nitrogen fertilization, and <span class="hlt">sea</span> <span class="hlt">level</span> rise.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Adam Langley, J; Mozdzer, Thomas J; Shepard, Katherine A; Hagerty, Shannon B; Patrick Megonigal, J</p> <p>2013-05-01</p> <p>Elevated CO2 and nitrogen (N) addition directly <span class="hlt">affect</span> plant productivity and the mechanisms that allow tidal marshes to maintain a constant elevation relative to <span class="hlt">sea</span> <span class="hlt">level</span>, but it remains unknown how these global change drivers modify marsh plant response to <span class="hlt">sea</span> <span class="hlt">level</span> rise. Here we manipulated factorial combinations of CO2 concentration (two <span class="hlt">levels</span>), N availability (two <span class="hlt">levels</span>) and relative <span class="hlt">sea</span> <span class="hlt">level</span> (six <span class="hlt">levels</span>) using in situ mesocosms containing a tidal marsh community composed of a sedge, Schoenoplectus americanus, and a grass, Spartina patens. Our objective is to determine, if elevated CO2 and N alter the growth and persistence of these plants in coastal ecosystems facing rising <span class="hlt">sea</span> <span class="hlt">levels</span>. After two growing seasons, we found that N addition enhanced plant growth particularly at <span class="hlt">sea</span> <span class="hlt">levels</span> where plants were most stressed by flooding (114% stimulation in the + 10 cm treatment), and N effects were generally larger in combination with elevated CO2 (288% stimulation). N fertilization shifted the optimal productivity of S. patens to a higher <span class="hlt">sea</span> <span class="hlt">level</span>, but did not confer S. patens an enhanced ability to tolerate <span class="hlt">sea</span> <span class="hlt">level</span> rise. S. americanus responded strongly to N only in the higher <span class="hlt">sea</span> <span class="hlt">level</span> treatments that excluded S. patens. Interestingly, addition of N, which has been suggested to accelerate marsh loss, may afford some marsh plants, such as the widespread sedge, S. americanus, the enhanced ability to tolerate inundation. However, if chronic N pollution reduces the availability of propagules of S. americanus or other flood-tolerant species on the landscape scale, this shift in species dominance could render tidal marshes more susceptible to marsh collapse.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMPA21B1871W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMPA21B1871W"><span>Communicating uncertainties in assessments of future <span class="hlt">sea</span> <span class="hlt">level</span> rise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wikman-Svahn, P.</p> <p>2013-12-01</p> <p>How uncertainty should be managed and communicated in policy-relevant scientific assessments is directly connected to the role of science and the responsibility of scientists. These fundamentally philosophical issues influence how scientific assessments are made and how scientific findings are communicated to policymakers. It is therefore of high importance to discuss implicit assumptions and value judgments that are made in policy-relevant scientific assessments. The present paper examines these issues for the case of scientific assessments of future <span class="hlt">sea</span> <span class="hlt">level</span> rise. The magnitude of future <span class="hlt">sea</span> <span class="hlt">level</span> rise is very uncertain, mainly due to poor scientific understanding of all physical mechanisms <span class="hlt">affecting</span> the great ice sheets of Greenland and Antarctica, which together hold enough land-based ice to raise <span class="hlt">sea</span> <span class="hlt">levels</span> more than 60 meters if completely melted. There has been much confusion from policymakers on how different assessments of future <span class="hlt">sea</span> <span class="hlt">levels</span> should be interpreted. Much of this confusion is probably due to how uncertainties are characterized and communicated in these assessments. The present paper draws on the recent philosophical debate on the so-called "value-free ideal of science" - the view that science should not be based on social and ethical values. Issues related to how uncertainty is handled in scientific assessments are central to this debate. This literature has much focused on how uncertainty in data, parameters or models implies that choices have to be made, which can have social consequences. However, less emphasis has been on how uncertainty is characterized when communicating the findings of a study, which is the focus of the present paper. The paper argues that there is a tension between on the one hand the value-free ideal of science and on the other hand usefulness for practical applications in society. This means that even if the value-free ideal could be upheld in theory, by carefully constructing and hedging statements characterizing</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.G33C..02B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.G33C..02B"><span>Regional <span class="hlt">Sea</span> <span class="hlt">Level</span> Variation: California Coastal Subsidence (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blewitt, G.; Hammond, W. C.; Nerem, R.</p> <p>2013-12-01</p> <p> of the coast north of the MTJ in Oregon and Washington has the opposite sign (uplift) and varies with distance between the coast and the trench, as may be expected from elastic strain accumulation at the locked subduction zone, coupled with a contrast in rheological structure <span class="hlt">affecting</span> GIA. In terms of LSL and hence societal impact, our measured mean California subsidence of 0.5 mm/yr approximately cancels with GIA models of global GSL lowering at a similar rate. This GSL lowering is caused by the increasing volume of ocean basins as the mantle flows away from under the oceans in isostatic response to >100 m of <span class="hlt">sea</span> <span class="hlt">level</span> rise following Pleistocene deglaciation. So the net LSL in California caused by coastal VLM plus GSL lowering by GIA is ~0.5 mm/yr LSL rise to the north, and ~0.5 mm/yr lowering to the south. Since our VLM estimates do not account for large earthquakes, the trends in LSL over geological time could look quite different. Given that our GPS time series are selected from a globally consistent set from >11,000 stations, we note that similar studies could be applied using our dataset in a seamless way over coastlines across the globe, depending on available station coverage.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010OcSci...6..311I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010OcSci...6..311I"><span>Seasonal variability of the Caspian <span class="hlt">Sea</span> three-dimensional circulation, <span class="hlt">sea</span> <span class="hlt">level</span> and air-<span class="hlt">sea</span> interaction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ibrayev, R. A.; Özsoy, E.; Schrum, C.; Sur, H. I.</p> <p>2010-03-01</p> <p>A three-dimensional primitive equation model including <span class="hlt">sea</span> ice thermodynamics and air-<span class="hlt">sea</span> interaction is used to study seasonal circulation and water mass variability in the Caspian <span class="hlt">Sea</span> under the influence of realistic mass, momentum and heat fluxes. River discharges, precipitation, radiation and wind stress are seasonally specified in the model, based on available data sets. The evaporation rate, sensible and latent heat fluxes at the <span class="hlt">sea</span> surface are computed interactively through an atmospheric boundary layer sub-model, using the ECMWF-ERA15 re-analysis atmospheric data and model generated <span class="hlt">sea</span> surface temperature. The model successfully simulates <span class="hlt">sea-level</span> changes and baroclinic circulation/mixing features with forcing specified for a selected year. The results suggest that the seasonal cycle of wind stress is crucial in producing basin circulation. Seasonal cycle of <span class="hlt">sea</span> surface currents presents three types: cyclonic gyres in December-January; Eckman south-, south-westward drift in February-July embedded by western and eastern southward coastal currents and transition type in August-November. Western and eastern northward sub-surface coastal currents being a result of coastal local dynamics at the same time play an important role in meridional redistribution of water masses. An important part of the work is the simulation of <span class="hlt">sea</span> surface topography, yielding verifiable results in terms of <span class="hlt">sea</span> <span class="hlt">level</span>. The model successfully reproduces <span class="hlt">sea</span> <span class="hlt">level</span> variability for four coastal points, where the observed data are available. Analyses of heat and water budgets confirm climatologic estimates of heat and moisture fluxes at the <span class="hlt">sea</span> surface. Experiments performed with variations in external forcing suggest a sensitive response of the circulation and the water budget to atmospheric and river forcing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009OcScD...6.1913I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009OcScD...6.1913I"><span>Seasonal variability of the Caspian <span class="hlt">Sea</span> three-dimensional circulation, <span class="hlt">sea</span> <span class="hlt">level</span> and air-<span class="hlt">sea</span> interaction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ibrayev, R. A.; Özsoy, E.; Schrum, C.; Sur, H. İ.</p> <p>2009-09-01</p> <p>A three-dimensional primitive equation model including <span class="hlt">sea</span> ice thermodynamics and air-<span class="hlt">sea</span> interaction is used to study seasonal circulation and water mass variability in the Caspian <span class="hlt">Sea</span> under the influence of realistic mass, momentum and heat fluxes. River discharges, precipitation, radiation and wind stress are seasonally specified in the model, based on available data sets. The evaporation rate, sensible and latent heat fluxes at the <span class="hlt">sea</span> surface are computed interactively through an atmospheric boundary layer sub-model, using the ECMWF-ERA15 re-analysis atmospheric data and model generated <span class="hlt">sea</span> surface temperature. The model successfully simulates <span class="hlt">sea-level</span> changes and baroclinic circulation/mixing features with forcing specified for a selected year. The results suggest that the seasonal cycle of wind stress is crucial in producing basin circulation. Seasonal cycle of <span class="hlt">sea</span> surface currents presents three types: cyclonic gyres in December-January; Eckman south-, south-westward drift in February-July embedded by western and eastern southward coastal currents and transition type in August-November. Western and eastern northward sub-surface coastal currents being a result of coastal local dynamics at the same time play an important role in meridional redistribution of water masses. An important part of the work is the simulation of <span class="hlt">sea</span> surface topography, yielding verifiable results in terms of <span class="hlt">sea</span> <span class="hlt">level</span>. Model successfully reproduces <span class="hlt">sea</span> <span class="hlt">level</span> variability for four coastal points, where the observed data are available. Analyses of heat and water budgets confirm climatologic estimates of heat and moisture fluxes at the <span class="hlt">sea</span> surface. Experiments performed with variations in external forcing suggest a sensitive response of the circulation and the water budget to atmospheric and river forcing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.V53A3127H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.V53A3127H"><span><span class="hlt">Sea</span> <span class="hlt">level</span> Variability and Juan de Fuca Bathymetry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huybers, P. J.; Boulahanis, B.; Proistosescu, C.; Langmuir, C. H.; Carbotte, S. M.; Katz, R. F.</p> <p>2015-12-01</p> <p>That deglaciation influences mid-ocean ridge volcanism is well established for Iceland, where depressurization associated with melting a ~2 km ice cap led to order of magnitude increases in volcanism during the last deglaciation. The case was also made that the more subtle ~100 m changes in <span class="hlt">sea</span> <span class="hlt">level</span> that accompany glacial cycles have identifiable implications for undersea mid-ocean ridge systems using both models and data from the Australian-Antarctic Ridge (Crowley et al., 2015). <span class="hlt">Sea</span> <span class="hlt">level</span> rising at ~1 cm/year during deglaciation leads to an expectation of ~10% decreases in melt production at ridges, given mantle upwelling rates of ˜3 cm/yr at intermediate spreading ridges and mantle density being ~3 times that of seawater. The implications of variations in melt production for bathymetry, however, involve numerous considerations, including whether melt signals are cancelled within the melt column, appreciably alter accretionary or fault processes, and have identifiable surface expressions. Further empirical assessment of bathymetry is thus useful for purposes of confirming patterns and constraining processes. Here we report on spectral analyses of bathymetry recently acquired from the Juan de Fuca ridge between 44°30'N and 45°15'N during the <span class="hlt">Sea</span>VOICE expedition. Multibeam swath sonar data were acquired with an EM122 sonar insonfiying seafloor to crustal ages of ˜2 ma with 35 m spatial resolution. We examine (1.) the statistical significance of concentrations of bathymetric variability at the 100 ky, 41 ky, and 23 ky periods characteristic of late-Pleistocene <span class="hlt">sea</span> <span class="hlt">level</span> variability; (2.) whether <span class="hlt">sea</span> <span class="hlt">level</span> responses are primarily at 41 ky periods in crust accreted during the early Pleistocene, when global <span class="hlt">sea</span> <span class="hlt">level</span> variations were primarily at this period; and (3.) if <span class="hlt">sea</span> <span class="hlt">level</span> responses are superimposed on bathymetry variations or, instead, align with fault features. We also note that Juan de Fuca's proximity to the Cordilleran Ice Sheet implies that regional</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110023308','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110023308"><span>Experiments in Reconstructing Twentieth-Century <span class="hlt">Sea</span> <span class="hlt">Levels</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ray, Richard D.; Douglas, Bruce C.</p> <p>2011-01-01</p> <p>One approach to reconstructing historical <span class="hlt">sea</span> <span class="hlt">level</span> from the relatively sparse tide-gauge network is to employ Empirical Orthogonal Functions (EOFs) as interpolatory spatial basis functions. The EOFs are determined from independent global data, generally <span class="hlt">sea</span>-surface heights from either satellite altimetry or a numerical ocean model. The problem is revisited here for <span class="hlt">sea</span> <span class="hlt">level</span> since 1900. A new approach to handling the tide-gauge datum problem by direct solution offers possible advantages over the method of integrating <span class="hlt">sea-level</span> differences, with the potential of eventually adjusting datums into the global terrestrial reference frame. The resulting time series of global mean <span class="hlt">sea</span> <span class="hlt">levels</span> appears fairly insensitive to the adopted set of EOFs. In contrast, charts of regional <span class="hlt">sea</span> <span class="hlt">level</span> anomalies and trends are very sensitive to the adopted set of EOFs, especially for the sparser network of gauges in the early 20th century. The reconstructions appear especially suspect before 1950 in the tropical Pacific. While this limits some applications of the <span class="hlt">sea-level</span> reconstructions, the sensitivity does appear adequately captured by formal uncertainties. All our solutions show regional trends over the past five decades to be fairly uniform throughout the global ocean, in contrast to trends observed over the shorter altimeter era. Consistent with several previous estimates, the global <span class="hlt">sea-level</span> rise since 1900 is 1.70 +/- 0.26 mm/yr. The global trend since 1995 exceeds 3 mm/yr which is consistent with altimeter measurements, but this large trend was possibly also reached between 1935 and 1950.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3871948','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3871948"><span>Impact of Altimeter Data Processing on <span class="hlt">Sea</span> <span class="hlt">Level</span> Studies</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Fernandes, M. Joana; Barbosa, Susana; Lázaro, Clara</p> <p>2006-01-01</p> <p>This study addresses the impact of satellite altimetry data processing on <span class="hlt">sea</span> <span class="hlt">level</span> studies at regional scale, with emphasis on the influence of various geophysical corrections and satellite orbit on the structure of the derived interannual signal and <span class="hlt">sea</span> <span class="hlt">level</span> trend. The work focuses on the analysis of TOPEX data for a period of over twelve years, for three regions in the North Atlantic: Tropical (0°≤φ≤25°), Sub-Tropical (25°≤φ≤50°) and Sub-Arctic (50°≤φ≤65°). For this analysis corrected <span class="hlt">sea</span> <span class="hlt">level</span> anomalies with respect to a mean <span class="hlt">sea</span> surface model have been derived from the GDR-Ms provided by AVISO by applying various state-of-the-art models for the geophysical corrections. Results show that <span class="hlt">sea</span> <span class="hlt">level</span> trend determined from TOPEX altimetry is dependent on the adopted models for the major geophysical corrections. The main effects come from the <span class="hlt">sea</span> state bias (SSB), and from the application or not of the inverse barometer (IB) correction. After an appropriate modelling of the TOPEX A/B bias, the two analysed SSB models induce small variations in <span class="hlt">sea</span> <span class="hlt">level</span> trend, from 0.0 to 0.2 mm/yr, with a small latitude dependence. The difference in <span class="hlt">sea</span> <span class="hlt">level</span> trend determined by a non IB-corrected series and an IB-corrected one has a strong regional dependence with large differences in the shape of the interannual signals and in the derived linear trends. The use of two different drift models for the TOPEX Microwave Radiometer (TMR) has a small but non negligible effect on the North Atlantic <span class="hlt">sea</span> <span class="hlt">level</span> trend of about 0.1 mm/yr. The interannual signals of <span class="hlt">sea</span> <span class="hlt">level</span> time series derived with the NASA and the CNES orbits respectively, show a small departure in the middle of the series, which has no impact on the derived <span class="hlt">sea</span> <span class="hlt">level</span> trend. These results strike the need for a continuous improvement in the modelling of the various effects that influence the altimeter measurement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUFMOS71D0325D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUFMOS71D0325D"><span>Extending the Instrumental Record of <span class="hlt">Sea-Level</span> Change: A 1300-Year <span class="hlt">Sea-Level</span> Record From Eastern Connecticut</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Donnelly, J. P.; Cleary, P.</p> <p>2002-12-01</p> <p>The instrumental record of <span class="hlt">sea-level</span> change in the northeastern United States extends back to the early 20th century and at New York City (NYC) extends back to 1856. These tide gauge records indicate that <span class="hlt">sea</span> <span class="hlt">level</span> has risen at a rate of 2.5 to 4 mm/year over the last 100-150 years. Geologic evidence of <span class="hlt">sea-level</span> change in the region over the last 2,000 years indicates rates of <span class="hlt">sea-level</span> rise of about 1 mm/year or less. The discordance between the instrumental and geologic records is frequently cited as potentially providing evidence that anthropogenic warming of the climate system has resulted in an increase in the rate of <span class="hlt">sea-level</span> rise. In order to begin to test the hypothesis that acceleration in the rate of <span class="hlt">sea-level</span> rise has occurred in the last 150 years due to anthropogenic climate warming, accurate and precise information on the timing of the apparent acceleration in <span class="hlt">sea-level</span> rise are needed. Here we construct a high-resolution relative <span class="hlt">sea-level</span> record for the past 1350 years by dating basal salt marsh peat samples above a glacial erratic in a western Connecticut salt marsh. Preservation of marsh vegetation remains in the sediment record that has a narrow vertical habitat range at the upper end of the tidal range provides information on past <span class="hlt">sea</span> <span class="hlt">levels</span>. { \\it Spartina patens} (marsh hay) and { \\it Juncus gerardi} (black rush) dominate both the modern marsh and their remains are the major constituent of the marsh sediments and occur in the modern marsh between mean high water (MHW) and mean highest high water. We use the elevation distribution of modern plant communities to estimate the relationship of sediment samples to paleo-mean high water. The chronology is based on 15 radiocarbon ages, supplemented by age estimates derived from the horizons of industrial Pb pollution and pollen indicative of European land clearance. Thirteen of the radiocarbon ages and the Pb and pollen data come from samples taken along a contact between marsh peat and a glacial</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920048967&hterms=Barometers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DBarometers','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920048967&hterms=Barometers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DBarometers"><span>Orthogonal stack of global tide gauge <span class="hlt">sea</span> <span class="hlt">level</span> data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Trupin, A.; Wahr, J.</p> <p>1990-01-01</p> <p>Yearly and monthly tide gauge <span class="hlt">sea</span> <span class="hlt">level</span> data from around the globe are fitted to numerically generated equilibrium tidal data to search for the 18.6 year lunar tide and 14 month pole tide. Both tides are clearly evident in the results, and their amplitudes and phases are found to be consistent with a global equilibrium response. Global, monthly <span class="hlt">sea</span> <span class="hlt">level</span> data from outside the Baltic <span class="hlt">sea</span> and Gulf of Bothnia are fitted to global atmospheric pressure data to study the response of the ocean to pressure fluctuations. The response is found to be inverted barometer at periods greater than two months. Global averages of tide gauge data, after correcting for the effects of post glacial rebound on individual station records, reveal an increase in <span class="hlt">sea</span> <span class="hlt">level</span> over the last 80 years of between 1.1 mm/yr and 1.9 mm/yr.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2013/1081/pdf/ofr20131081.pdf','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2013/1081/pdf/ofr20131081.pdf"><span>Final report for <span class="hlt">sea-level</span> rise response modeling for San Francisco Bay estuary tidal marshes</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Takekawa, John Y.; Thorne, Karen M.; Buffington, Kevin J.; Spragens, Kyle A.; Swanson, Kathleen M.; Drexler, Judith Z.; Schoellhamer, David H.; Overton, Cory T.; Casazza, Michael L.</p> <p>2013-01-01</p> <p>The International Panel on Climate Change has identified coastal ecosystems as areas that will be disproportionally <span class="hlt">affected</span> by climate change. Current <span class="hlt">sea-level</span> rise projections range widely with 0.57 to 1.9 meters increase in mea <span class="hlt">sea</span> <span class="hlt">level</span> by 2100. The expected accelerated rate of <span class="hlt">sea-level</span> rise through the 21st century will put many coastal ecosystems at risk, especially those in topographically low-gradient areas. We assessed marsh accretion and plant community state changes through 2100 at 12 tidal salt marshes around San Francisco Bay estuary with a <span class="hlt">sea-level</span> rise response model. Detailed ground elevation, vegetation, and water <span class="hlt">level</span> data were collected at all sites between 2008 and 2011 and used as model inputs. Sediment cores (taken by Callaway and others, 2012) at four sites around San Francisco Bay estuary were used to estimate accretion rates. A modification of the Callaway and others (1996) model, the Wetland Accretion Rate Model for Ecosystem Resilience (WARMER), was utilized to run <span class="hlt">sea-level</span> rise response models for all sites. With a mean <span class="hlt">sea</span> <span class="hlt">level</span> rise of 1.24 m by 2100, WARMER projected that the vast majority, 95.8 percent (1,942 hectares), of marsh area in our study will lose marsh plant communities by 2100 and to transition to a relative elevation range consistent with mudflat habitat. Three marshes were projected to maintain marsh vegetation to 2100, but they only composed 4.2 percent (85 hectares) of the total marsh area surveyed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014GeoJI.199.1018N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014GeoJI.199.1018N"><span>Simultaneous estimation of lithospheric uplift rates and absolute <span class="hlt">sea</span> <span class="hlt">level</span> change in southwest Scandinavia from inversion of <span class="hlt">sea</span> <span class="hlt">level</span> data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nielsen, Lars; Hansen, Jens Morten; Hede, Mikkel Ulfeldt; Clemmensen, Lars B.; Pejrup, Morten; Noe-Nygaard, Nanna</p> <p>2014-11-01</p> <p>Relative <span class="hlt">sea</span> <span class="hlt">level</span> curves contain coupled information about absolute <span class="hlt">sea</span> <span class="hlt">level</span> change and vertical lithospheric movement. Such curves may be constructed based on, for example tide gauge data for the most recent times and different types of geological data for ancient times. Correct account for vertical lithospheric movement is essential for estimation of reliable values of absolute <span class="hlt">sea</span> <span class="hlt">level</span> change from relative <span class="hlt">sea</span> <span class="hlt">level</span> data and vise versa. For modern times, estimates of vertical lithospheric movement may be constrained by data (e.g. GPS-based measurements), which are independent from the relative <span class="hlt">sea</span> <span class="hlt">level</span> data. Similar independent data do not exist for ancient times. The purpose of this study is to test two simple inversion approaches for simultaneous estimation of lithospheric uplift rates and absolute <span class="hlt">sea</span> <span class="hlt">level</span> change rates for ancient times in areas where a dense coverage of relative <span class="hlt">sea</span> <span class="hlt">level</span> data exists and well-constrained average lithospheric movement values are known from, for example glacial isostatic adjustment (GIA) models. The inversion approaches are tested and used for simultaneous estimation of lithospheric uplift rates and absolute <span class="hlt">sea</span> <span class="hlt">level</span> change rates in southwest Scandinavia from modern relative <span class="hlt">sea</span> <span class="hlt">level</span> data series that cover the period from 1900 to 2000. In both approaches, a priori information is required to solve the inverse problem. A priori information about the average vertical lithospheric movement in the area of interest is critical for the quality of the obtained results. The two tested inversion schemes result in estimated absolute <span class="hlt">sea</span> <span class="hlt">level</span> rise of ˜1.2/1.3 mm yr-1 and vertical uplift rates ranging from approximately -1.4/-1.2 mm yr-1 (subsidence) to about 5.0/5.2 mm yr-1 if an a priori value of 1 mm yr-1 is used for the vertical lithospheric movement throughout the study area. In case the studied time interval is broken into two time intervals (before and after 1970), absolute <span class="hlt">sea</span> <span class="hlt">level</span> rise values of ˜0.8/1.2 mm yr-1 (before</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.7156C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.7156C"><span>The Enigma of 20th century <span class="hlt">sea</span> <span class="hlt">level</span> change</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cathles, Larry</p> <p>2014-05-01</p> <p><span class="hlt">Sea</span> <span class="hlt">level</span> has been constant at near-present <span class="hlt">levels</span> from ~5500 calendar years BP to the end of the Little Ice Age at ~1860 AD. Since ~1900, tide gauge measurements indicate that it has risen steadily at ~2 mm/yr by about 18 cm. The comparative stability of sealevel from 5500 cal yr BP to 1860 AD is robust, being suggested by near-shore Mediterranean archeological sites, the few <span class="hlt">sea</span> <span class="hlt">level</span> records that extend back to 1700 AD, and the impossibility of projecting the current <span class="hlt">sea</span> <span class="hlt">level</span> rise of ~2 mm/y back 5000 years (it would produce a global 10 m inundation, which is not observed) (Douglas et al., 2001, Academic Press). The post 1870 <span class="hlt">sea</span> <span class="hlt">level</span> rise is not due to heating of the upper ocean (Liviticus et al., 2000, Science). Munk (2002, PNAS) characterized it as an "enigma", dismissing an upper ocean steric <span class="hlt">sea</span> <span class="hlt">level</span> explanation as "too little" (~3 cm), "too late" (the rise started in 1860), and "too linear" (not accelerating with the accelerating CO2 increase). GRACE gravity measurements show a near zero change in ocean mass. Cazenave et al. (2009, Global and Planetary Change) indicate a slight decrease in ocean mass between 2003 and 2008. The rate of meltwater mass being added to the oceans essentially equals the GIA correction (Chambers et al., 2010, JGR). Different GIA models give ocean mass increase ranging from 0.5 to 2 mm/y of equivalent <span class="hlt">sea</span> <span class="hlt">level</span> rise. Our GIA model suggests no ocean mass increases (~0 mm/y of equivalent <span class="hlt">sea</span> <span class="hlt">level</span> rise). In this talk I show that the heating of a two layer ocean model driven by the temperature changes that have occurred over the last 1000 years since the peak of the Medieval Warm Period produces a ~2mm/yr linear <span class="hlt">sea</span> <span class="hlt">level</span> rise over the last 100 years with much smaller preceding <span class="hlt">sea</span> <span class="hlt">level</span> changes. Ocean mass could be unchanging over the last century as well as the last ~5000 years. This result is compatible with GRACE measurements and eclipse data constraints, predictions of our GIA model, and it resolves the enigma the 20th</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4150292','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4150292"><span><span class="hlt">Sea</span> <span class="hlt">level</span>: measuring the bounding surfaces of the ocean</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Tamisiea, Mark E.; Hughes, Chris W.; Williams, Simon D. P.; Bingley, Richard M.</p> <p>2014-01-01</p> <p>The practical need to understand <span class="hlt">sea</span> <span class="hlt">level</span> along the coasts, such as for safe navigation given the spatially variable tides, has resulted in tide gauge observations having the distinction of being some of the longest instrumental ocean records. Archives of these records, along with geological constraints, have allowed us to identify the century-scale rise in global <span class="hlt">sea</span> <span class="hlt">level</span>. Additional data sources, particularly satellite altimetry missions, have helped us to better identify the rates and causes of <span class="hlt">sea-level</span> rise and the mechanisms leading to spatial variability in the observed rates. Analysis of all of the data reveals the need for long-term and stable observation systems to assess accurately the regional changes as well as to improve our ability to estimate future changes in <span class="hlt">sea</span> <span class="hlt">level</span>. While information from many scientific disciplines is needed to understand <span class="hlt">sea-level</span> change, this review focuses on contributions from geodesy and the role of the ocean's bounding surfaces: the <span class="hlt">sea</span> surface and the Earth's crust. PMID:25157196</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25157196','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25157196"><span><span class="hlt">Sea</span> <span class="hlt">level</span>: measuring the bounding surfaces of the ocean.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tamisiea, Mark E; Hughes, Chris W; Williams, Simon D P; Bingley, Richard M</p> <p>2014-09-28</p> <p>The practical need to understand <span class="hlt">sea</span> <span class="hlt">level</span> along the coasts, such as for safe navigation given the spatially variable tides, has resulted in tide gauge observations having the distinction of being some of the longest instrumental ocean records. Archives of these records, along with geological constraints, have allowed us to identify the century-scale rise in global <span class="hlt">sea</span> <span class="hlt">level</span>. Additional data sources, particularly satellite altimetry missions, have helped us to better identify the rates and causes of <span class="hlt">sea-level</span> rise and the mechanisms leading to spatial variability in the observed rates. Analysis of all of the data reveals the need for long-term and stable observation systems to assess accurately the regional changes as well as to improve our ability to estimate future changes in <span class="hlt">sea</span> <span class="hlt">level</span>. While information from many scientific disciplines is needed to understand <span class="hlt">sea-level</span> change, this review focuses on contributions from geodesy and the role of the ocean's bounding surfaces: the <span class="hlt">sea</span> surface and the Earth's crust.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2010-08-09/pdf/2010-19557.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2010-08-09/pdf/2010-19557.pdf"><span>75 FR 47825 - Emergency Exemption; Issuance of Emergency Permit to Rehabilitate <span class="hlt">Sea</span> Turtles <span class="hlt">Affected</span> by the...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2010-08-09</p> <p>... Fish and Wildlife Service Emergency Exemption; Issuance of Emergency Permit to Rehabilitate <span class="hlt">Sea</span> Turtles... <span class="hlt">sea</span> turtle species. We, the U.S. Fish and Wildlife Service have authorized Texas State Aquarium, under an Endangered Species Act (ESA) permit, to aid <span class="hlt">sea</span> turtles <span class="hlt">affected</span> by the oil spill....</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NLE.....5...37P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NLE.....5...37P"><span>Analysis of the <span class="hlt">sea</span> <span class="hlt">levels</span> in Kiribati A Rising <span class="hlt">Sea</span> of Misrepresentation Sinks Kiribati</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Parker, Albert</p> <p>2016-03-01</p> <p>The <span class="hlt">sea</span> <span class="hlt">levels</span> of Kiribati have been stable over the last few decades, as elsewhere in the world. The Australian government funded Pacific <span class="hlt">Sea</span> <span class="hlt">Level</span> Monitoring (PSLM) project has adjusted <span class="hlt">sea</span> <span class="hlt">level</span> records to produce an unrealistic rising trend. Some information has been hidden or neglected, especially from sources of different management. The measured monthly average mean <span class="hlt">sea</span> <span class="hlt">levels</span> suffer from subsidence or manipulation resulting in a tilting from the about 0 (zero) mm/year of nearby tide gauges to 4 (four) mm/year over the same short time window. Real environmental problems are driven by the increasing local population leading to troubles including scarcity of water, localized sinking and localised erosion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012QSRv...40...54C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012QSRv...40...54C"><span>Quantitative constraints on the <span class="hlt">sea-level</span> fall that terminated the Littorina <span class="hlt">Sea</span> Stage, southern Scandinavia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clemmensen, Lars B.; Murray, Andrew S.; Nielsen, Lars</p> <p>2012-04-01</p> <p>The island of Anholt in the Kattegat <span class="hlt">sea</span> (southern Scandinavia) is made up largely of an extensive beach-ridge plain. As a result of post-glacial uplift, the earliest beach-ridge and swale deposits are now raised 8-9 m above present mean <span class="hlt">sea</span> <span class="hlt">level</span>. It appears that growth of the plain has been almost uninterrupted over the past 7500 years; here we constrain the evolution of this plain between 6300 and 1300 years ago using optically stimulated luminescence dates. The topography and internal architecture of the fossil shoreline deposits were measured on high-resolution maps and in ground-penetrating radar (GPR) reflection data with a vertical resolution of ˜0.25 m. Shoreline topography shows significant changes with time, and it appears that one of the most striking changes took place between 4300 and 3600 years ago; in the shoreline deposits corresponding to this time interval the surface drops by around 3.5 m suggesting a marked fall in relative <span class="hlt">sea-level</span>. Assuming a constant uplift rate of 1.2 mm/yr, the corresponding drop in absolute <span class="hlt">sea-level</span> is estimated to be around 2.6 m. This marked <span class="hlt">sea-level</span> fall in 700 years took place at the transition from the Middle Holocene Thermal Maximum to the Late Holocene Thermal Decline or at the end of the Littorina <span class="hlt">Sea</span> stage in the Baltic <span class="hlt">Sea</span> region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMGC43D0968T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMGC43D0968T"><span>On Early Holocene Ice-Sheet/<span class="hlt">Sea-Level</span> Interactions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tornqvist, T. E.; Hijma, M.</p> <p>2011-12-01</p> <p>Early Holocene <span class="hlt">sea-level</span> change constitutes an imperfect, yet potentially valuable analog for future <span class="hlt">sea-level</span> rise, given the rapidly disintegrating land-based ice under climate conditions of high-latitude Northern Hemisphere warming. The associated rates of eustatic <span class="hlt">sea-level</span> rise (cm/yr order of magnitude) fall within the range of predictions for the latter part of the next century. However, the early Holocene eustatic <span class="hlt">sea-level</span> history is otherwise rather poorly understood. Recent impetus has been provided by new records of both relative <span class="hlt">sea-level</span> (RSL) change and ice-sheet retreat that are sometimes difficult to reconcile in terms of timing and magnitude of change. We first summarize the state-of-the-art on early Holocene <span class="hlt">sea-level</span> change and then identify key near-term research needs. Recent studies have identified a number of decimeter to meter-scale <span class="hlt">sea-level</span> jumps, several of which have been linked to catastrophic drainage of proglacial Lake Agassiz and the 8.2 ka cooling event. It is increasingly clear that this occurred by means of two successive jumps, separated by up to a few centuries, and only the latter (and final) one coinciding with the 8.2 ka climate event proper. We show that a considerable research effort, including near-field, intermediate-field, and far-field localities across the globe is needed to fully understand the timing and magnitude of these <span class="hlt">sea-level</span> jumps. Accomplishing this goal would in addition offer a unique opportunity for rigorous testing of gravitational theory and associated <span class="hlt">sea-level</span> fingerprinting that plays a critical role in predicting future <span class="hlt">sea-level</span> change. A more enigmatic <span class="hlt">sea-level</span> jump that has been identified around 7.6 ka has received renewed interest both by means of new RSL data from Fennoscandia and reconstructions of Laurentide Ice Sheet retreat. However, the proposed ~5 m abrupt rise in eustatic <span class="hlt">sea</span> <span class="hlt">level</span> cannot be detected in relatively nearby, detailed RSL records from NW Europe, thus presenting a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AGUFMPP12A0233B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AGUFMPP12A0233B"><span><span class="hlt">Sea-level</span> and the `Stage 11 Problem`</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bowen, D. Q.</p> <p>2003-12-01</p> <p>Estimating an approximate relative <span class="hlt">sea</span> <span class="hlt">level</span> for oxygen isotope stage 11 may have a critical bearing on a solution to the `stage 11 problem` that identifies the mismatch between low eccentricity forcing and the disproportionate ice volume response - that also includes a relative <span class="hlt">sea</span> <span class="hlt">level</span> response. The perennial problem of separating ice volume from temperature effects has hampered attempts to estimate <span class="hlt">sea</span> <span class="hlt">level</span> from delta 18O data sets, even for younger odd numbered stages when comparisons with U-series ages on corals are available. Stage 11 <span class="hlt">sea</span> <span class="hlt">levels</span> on `stable` and uplifting coasts are recognised from geomorphic features such as terraces and shoreline angles, sediments and corals, and yield a range of estimates from over 20 m to just below present <span class="hlt">sea</span> <span class="hlt">level</span>. Given that the 413 ka Milankovitch pacing provides similar orbital configurations for stage 11 and the Holocene some interest attaches to the potential <span class="hlt">sea-level</span> similarity between them, especially for the future Holocene. Attempts to derive a stage 11 <span class="hlt">sea</span> <span class="hlt">level</span> from coasts uplifting at different rates have used `uplift correction graphs` or uplift correction equations, but a major handicap is the dearth of appropriate geochronologic ages both for stage 11 and substage 5e (5.5) - the base line for estimating average uplift rates. Different estimates for the age of stage 11 and 5e (5.5), and the duration of 5e, have yielded a range of estimates. Earlier estimates relied on single locations or regional evidence, but it is probably misleading to rely on these. To combat this several world-wide locations are assembled and, using locality-specific data, provide a mean estimate for the stage 11 <span class="hlt">sea</span> <span class="hlt">level</span> of 11 m, plus-minus 10 m. But by applying a set of standardised parameters (including the peak <span class="hlt">sea</span> <span class="hlt">level</span> at 402 ka - event 11.3 of the Bassinott time scale) the mean <span class="hlt">sea</span> <span class="hlt">level</span> for stage 11 emerges as 2 m plus-minus 7 m. This closes the gap between inferences from delta 18O variability, the latest of which point</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18056644','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18056644"><span>Observational evidence for volcanic impact on <span class="hlt">sea</span> <span class="hlt">level</span> and the global water cycle.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Grinsted, A; Moore, J C; Jevrejeva, S</p> <p>2007-12-11</p> <p>It has previously been noted that there are drops in global <span class="hlt">sea</span> <span class="hlt">level</span> (GSL) after some major volcanic eruptions. However, observational evidence has not been convincing because there is substantial variability in the global <span class="hlt">sea</span> <span class="hlt">level</span> record over periods similar to those at which we expect volcanoes to have an impact. To quantify the impact of volcanic eruptions we average monthly GSL data from 830 tide gauge records around five major volcanic eruptions. Surprisingly, we find that the initial response to a volcanic eruption is a significant rise in <span class="hlt">sea</span> <span class="hlt">level</span> of 9 +/- 3 mm in the first year after the eruption. This rise is followed by a drop of 7 +/- 3 mm in the period 2-3 years after the eruption relative to preeruption <span class="hlt">sea</span> <span class="hlt">level</span>. These results are statistically robust and no particular volcanic eruption or ocean region dominates the signature we find. Neither the drop nor especially the rise in GSL can be explained by models of lower oceanic heat content. We suggest that the mechanism is a transient disturbance of the water cycle with a delayed response of land river runoff relative to ocean evaporation and global precipitation that <span class="hlt">affects</span> global <span class="hlt">sea</span> <span class="hlt">level</span>. The volcanic impact on the water cycle and <span class="hlt">sea</span> <span class="hlt">levels</span> is comparable in magnitude to that of a large El Niño-La Niña cycle, amounting to approximately 5% of global land precipitation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012NatGe...5..389P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012NatGe...5..389P"><span>Model estimates of <span class="hlt">sea-level</span> change due to anthropogenic impacts on terrestrial water storage</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pokhrel, Yadu N.; Hanasaki, Naota; Yeh, Pat J.-F.; Yamada, Tomohito J.; Kanae, Shinjiro; Oki, Taikan</p> <p>2012-06-01</p> <p>Global <span class="hlt">sea</span> <span class="hlt">level</span> has been rising over the past half century, according to tide-gauge data. Thermal expansion of oceans, melting of glaciers and loss of the ice masses in Greenland and Antarctica are commonly considered as the largest contributors, but these contributions do not entirely explain the observed <span class="hlt">sea-level</span> rise. Changes in terrestrial water storage are also likely to <span class="hlt">affect</span> <span class="hlt">sea</span> <span class="hlt">level</span>, but comprehensive and reliable estimates of this contribution, particularly through human water use, are scarce. Here, we estimate <span class="hlt">sea-level</span> change in response to human impacts on terrestrial water storage by using an integrated model that simulates global terrestrial water stocks and flows (exclusive to Greenland and Antarctica) and especially accounts for human activities such as reservoir operation and irrigation. We find that, together, unsustainable groundwater use, artificial reservoir water impoundment, climate-driven changes in terrestrial water storage and the loss of water from closed basins have contributed a <span class="hlt">sea-level</span> rise of about 0.77mmyr-1 between 1961 and 2003, about 42% of the observed <span class="hlt">sea-level</span> rise. We note that, of these components, the unsustainable use of groundwater represents the largest contribution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70141641','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70141641"><span><span class="hlt">Sea-level</span>-induced seismicity and submarine landslide occurrence</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Brothers, Daniel S.; Luttrell, Karen M.; Chaytor, Jason D.</p> <p>2013-01-01</p> <p>The temporal coincidence between rapid late Pleistocene <span class="hlt">sea-level</span> rise and large-scale slope failures is widely documented. Nevertheless, the physical mechanisms that link these phenomena are poorly understood, particularly along nonglaciated margins. Here we investigate the causal relationships between rapid <span class="hlt">sea-level</span> rise, flexural stress loading, and increased seismicity rates along passive margins. We find that Coulomb failure stress across fault systems of passive continental margins may have increased more than 1 MPa during rapid late Pleistocene–early Holocene <span class="hlt">sea-level</span> rise, an amount sufficient to trigger fault reactivation and rupture. These results suggest that <span class="hlt">sea</span>-level–modulated seismicity may have contributed to a number of poorly understood but widely observed phenomena, including (1) increased frequency of large-scale submarine landslides during rapid, late Pleistocene <span class="hlt">sea-level</span> rise; (2) emplacement of coarse-grained mass transport deposits on deep-<span class="hlt">sea</span> fans during the early stages of marine transgression; and (3) the unroofing and release of methane gas sequestered in continental slope sediments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013DyAtO..64....1G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013DyAtO..64....1G"><span>The statistical relation of <span class="hlt">sea-level</span> and temperature revisited</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grassi, Stefano; Hillebrand, Eric; Ventosa-Santaulària, Daniel</p> <p>2013-11-01</p> <p>We propose a semi-empirical model for the relation between global mean surface temperature and global <span class="hlt">sea-levels</span>. In contradistinction to earlier approaches to this problem, the model allows for valid statistical inference and joint estimation of trend components and interaction term of temperature and <span class="hlt">sea-level</span>. Estimation of the model on the data set used in Rahmstorf (2007) yields a proportionality coefficient of 4.6 mm/year per °C at a one-sided significance <span class="hlt">level</span> of 7.6 percent or higher. Long-term simulations of the model result in a two-sided 90-percent confidence interval for the <span class="hlt">sea-level</span> rise in the year 2100 of [15 cm, 150 cm] above the 1990 <span class="hlt">level</span>. This is a wider margin of error than was reported in the previous literature, and it reflects the substantial uncertainty in relating two trending time series.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.8656L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.8656L"><span>Evaluating future flooding risks by using a probabilistic approach to include wave height distributions in <span class="hlt">sea</span> <span class="hlt">level</span> variations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Leijala, Ulpu; Björkqvist, Jan-Victor; Kahma, Kimmo K.; Johansson, Milla M.; Pellikka, Hilkka; Särkkä, Jani</p> <p>2016-04-01</p> <p>Assessing <span class="hlt">sea</span> flood risks has an essential role in future coastal planning as climate change drives forward the global <span class="hlt">sea</span> <span class="hlt">level</span> rise. Safe planning of land utilization and building in coastal areas requires capability to estimate <span class="hlt">sea</span> <span class="hlt">level</span> behaviour all the way to 100-200 years ahead. The coastal effect of the <span class="hlt">sea</span> <span class="hlt">level</span> is always <span class="hlt">affected</span> also by the wave conditions, which may vary greatly depending on location. An archipelago acts as an efficient shield against the largest waves penetrating to the shoreline. However, part of the energy of the waves passes through the archipelago and coastal wave height conditions, depending for example on the shape of the shoreline and topography of the seabed, must be evaluated close to the shore separately. The probability of high <span class="hlt">sea</span> <span class="hlt">level</span> and wind generated high waves occurring simultaneously is lower than the probability of one of the components occurring alone. Summing the maximum <span class="hlt">sea</span> <span class="hlt">level</span> and maximum wave height components together can thus lead to an overestimation of the joint effect. For this reason a method based on probability distributions is reasonable and preferable. In this study, a method of combining <span class="hlt">sea</span> <span class="hlt">level</span> and wave height distributions using a location specific probability approach is introduced. First estimates of the joint effect of high <span class="hlt">sea</span> <span class="hlt">level</span> and high waves at several locations at the archipelago area on the southern coast of Finland are presented. Constructing <span class="hlt">sea</span> <span class="hlt">level</span> scenarios including the effect of wind waves until the end of the century demands knowledge of both <span class="hlt">sea</span> <span class="hlt">level</span> and wave height variability in the past, and global mean <span class="hlt">sea</span> <span class="hlt">level</span> predictions for the future. In our study, an estimate of short-term <span class="hlt">sea</span> <span class="hlt">level</span> variability is based on 30 years (1982-2011) of hourly data from the Helsinki tide gauge located on the coast of the Gulf of Finland. Future predictions for the long-term mean <span class="hlt">sea</span> <span class="hlt">level</span> changes at Helsinki are based on scenarios taking into account the global mean <span class="hlt">sea</span> <span class="hlt">level</span> rise</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015QuRes..84...69L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015QuRes..84...69L"><span>Late Quaternary <span class="hlt">sea-level</span> changes of the Persian Gulf</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lokier, Stephen W.; Bateman, Mark D.; Larkin, Nigel R.; Rye, Philip; Stewart, John R.</p> <p>2015-07-01</p> <p>Late Quaternary reflooding of the Persian Gulf climaxed with the mid-Holocene highstand previously variously dated between 6 and 3.4 ka. Examination of the stratigraphic and paleoenvironmental context of a mid-Holocene whale beaching allows us to accurately constrain the timing of the transgressive, highstand and regressive phases of the mid- to late Holocene <span class="hlt">sea-level</span> highstand in the Persian Gulf. Mid-Holocene transgression of the Gulf surpassed today's <span class="hlt">sea</span> <span class="hlt">level</span> by 7100-6890 cal yr BP, attaining a highstand of > 1 m above current <span class="hlt">sea</span> <span class="hlt">level</span> shortly after 5290-4570 cal yr BP before falling back to current <span class="hlt">levels</span> by 1440-1170 cal yr BP. The cetacean beached into an intertidal hardground pond during the transgressive phase (5300-4960 cal yr BP) with continued transgression interring the skeleton in shallow-subtidal sediments. Subsequent relative <span class="hlt">sea-level</span> fall produced a forced regression with consequent progradation of the coastal system. These new ages refine previously reported timings for the mid- to late Holocene <span class="hlt">sea-level</span> highstand published for other regions. By so doing, they allow us to constrain the timing of this correlatable global eustatic event more accurately.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRC..118.3999M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRC..118.3999M"><span>A nonstationary analysis for the Northern Adriatic extreme <span class="hlt">sea</span> <span class="hlt">levels</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Masina, Marinella; Lamberti, Alberto</p> <p>2013-09-01</p> <p>The historical data from the Trieste, Venice, Porto Corsini, and Rimini tide gauges have been used to investigate the spatial and temporal changes in extreme high water <span class="hlt">levels</span> in the Northern Adriatic. A detailed analysis of annual mean <span class="hlt">sea</span> <span class="hlt">level</span> evolution at the three longest operating stations shows a coherent behavior both on a regional and global scale. A slight increase in magnitude of extreme water elevations, after the removal of the regularized annual mean <span class="hlt">sea</span> <span class="hlt">level</span> necessary to eliminate the effect of local subsidence and <span class="hlt">sea</span> <span class="hlt">level</span> rise, is found at the Venice and Porto Corsini stations. It seems to be mainly associated with a wind regime change occurred in the 1990s, due to an intensification of Bora wind events after their decrease in frequency and intensity during the second half of the 20th century. The extreme values, adjusted for the annual mean <span class="hlt">sea</span> <span class="hlt">level</span> trend, are modeled using a time-dependent GEV distribution. The inclusion of seasonality in the GEV parameters considerably improves the data fitting. The interannual fluctuations of the detrended monthly maxima exhibit a significant correlation with the variability of the large-scale atmospheric circulation represented by the North Atlantic Oscillation and Arctic Oscillation indices. The different coast exposure to the Bora and Sirocco winds and their seasonal character explain the various seasonal patterns of extreme <span class="hlt">sea</span> <span class="hlt">levels</span> observed at the tide gauges considered in the present analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17813199','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17813199"><span><span class="hlt">Sea</span> <span class="hlt">level</span> at southern california: a decadal fluctuation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Namias, J; Chi Kan Huang, J</p> <p>1972-07-28</p> <p>The winter mean height of <span class="hlt">sea</span> <span class="hlt">level</span> at southern California rose 5.6 centimeters between the periods 1948-1957 and 1958-1969. These periods correspond to two fairly coherent large-scale climatic regimes with different air-<span class="hlt">sea</span> coupling, which were previously identified. The rise was mainly due to a change in the thermohaline structure of the water as a result of changes in prevailing winds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.7389N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.7389N"><span>Contribution of climate forcing to <span class="hlt">sea</span> <span class="hlt">level</span> variations in the Mediterranean <span class="hlt">Sea</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Natsiopoulos, Dimitrios A.; Vergos, Georgios S.; Tziavos, Ilias N.</p> <p>2016-04-01</p> <p>With the availability of an abundance of earth observation data from satellite altimetry missions as well as those from the ENVISAT and CRYOSAT-2 satellites, monitoring of the <span class="hlt">sea</span> <span class="hlt">level</span> variations is gaining increased importance. In this work, altimetric data sets from the satellite remote sensing missions of ENVISAT and CRYOSAT-2 have been used to study the variations of the Mediterranean <span class="hlt">sea</span> <span class="hlt">level</span>. Alongside, a correlation analysis of <span class="hlt">Sea</span> <span class="hlt">Level</span> Anomalies (SLAs) with global and regional climatic indexes that influence the ocean state, has been carried out as well. The raw data used were SLAs from the respective altimetric missions, acquired by the on-board altimeters from the ENVISAT satellite for seven consecutive years (2003-2009) and from the CRYOSAT-2 satellite for six consecutive years (2010-2015). Three oscillation indexes have been investigated, as representative of climate-change and seasonal forcing on the <span class="hlt">sea</span> <span class="hlt">level</span>. The first one was the well-known Southern Oscillation Index (SOI), the next one the North Atlantic Oscillation (NAO) index and the third, being primarily more representative of the Mediterranean <span class="hlt">sea</span> state, was the Mediterranean Oscillation Index (MOI). The possible correlation is investigated in both monthly and annual scales, while a regional multiple regression and a principal component analysis (PCA) between the SLAs and oscillation indexes is carried out. Multiple regression and PCA have been used as tools in order to deduce possible correlations between the Mediterranean <span class="hlt">sea</span> <span class="hlt">level</span> variations and the aforementioned oscillation indexes, under the assumption that SLA variations are driven by steric forcing. Finally, evidence of the <span class="hlt">sea</span> <span class="hlt">level</span> cyclo-stationarity in the Mediterranean <span class="hlt">Sea</span> is deduced from the analysis of empirically derived covariance functions at monthly intervals from the available SLA data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19830041107&hterms=global+cooling&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dglobal%2Bcooling','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19830041107&hterms=global+cooling&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dglobal%2Bcooling"><span>Global mean <span class="hlt">sea</span> <span class="hlt">level</span> - Indicator of climate change</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Robock, A.; Hansen, J.; Gornitz, V.; Lebedeff, S.; Moore, E.; Etkins, R.; Epstein, E.</p> <p>1983-01-01</p> <p>A critical discussion is presented on the use by Etkins and Epstein (1982) of combined surface air temperature and <span class="hlt">sea</span> <span class="hlt">level</span> time series to draw conclusions concerning the discharge of the polar ice sheets. It is objected by Robock that they used Northern Hemisphere land surface air temperature records which are unrepresentative of global <span class="hlt">sea</span> surface temperature, and he suggests that externally imposed volcanic dust and CO2 forcings can adequately account for observed temperature changes over the last century, with global <span class="hlt">sea</span> <span class="hlt">level</span> changing in passive response to <span class="hlt">sea</span> change as a result of thermal expansion. Hansen et al. adduce evidence for global cooling due to ice discharge that has not exceeded a few hundredths of a degree centigrade in the last century, precluding any importance of this phenomenon in the interpretation of global mean temperature trends for this period. Etkins and Epstein reply that since their 1982 report additional evidence has emerged for the hypothesis that the polar ice caps are diminishing. It is reasserted that each of the indices discussed, including global mean <span class="hlt">sea</span> surface temperature and <span class="hlt">sea</span> <span class="hlt">level</span>, polar ice sheet mass balance, water mass characteristics, and the spin rate and axis of rotation displacement of the earth, are physically linked and can be systematically monitored, as is currently being planned under the auspices of the National Climate Program.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4245127','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4245127"><span>Long-Memory and the <span class="hlt">Sea</span> <span class="hlt">Level</span>-Temperature Relationship: A Fractional Cointegration Approach</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Ventosa-Santaulària, Daniel; Heres, David R.; Martínez-Hernández, L. Catalina</p> <p>2014-01-01</p> <p>Through thermal expansion of oceans and melting of land-based ice, global warming is very likely contributing to the <span class="hlt">sea</span> <span class="hlt">level</span> rise observed during the 20th century. The amount by which further increases in global average temperature could <span class="hlt">affect</span> <span class="hlt">sea</span> <span class="hlt">level</span> is only known with large uncertainties due to the limited capacity of physics-based models to predict <span class="hlt">sea</span> <span class="hlt">levels</span> from global surface temperatures. Semi-empirical approaches have been implemented to estimate the statistical relationship between these two variables providing an alternative measure on which to base potentially disrupting impacts on coastal communities and ecosystems. However, only a few of these semi-empirical applications had addressed the spurious inference that is likely to be drawn when one nonstationary process is regressed on another. Furthermore, it has been shown that spurious effects are not eliminated by stationary processes when these possess strong long memory. Our results indicate that both global temperature and <span class="hlt">sea</span> <span class="hlt">level</span> indeed present the characteristics of long memory processes. Nevertheless, we find that these variables are fractionally cointegrated when <span class="hlt">sea</span>-ice extent is incorporated as an instrumental variable for temperature which in our estimations has a statistically significant positive impact on global <span class="hlt">sea</span> <span class="hlt">level</span>. PMID:25426638</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25426638','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25426638"><span>Long-memory and the <span class="hlt">sea</span> <span class="hlt">level</span>-temperature relationship: a fractional cointegration approach.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ventosa-Santaulària, Daniel; Heres, David R; Martínez-Hernández, L Catalina</p> <p>2014-01-01</p> <p>Through thermal expansion of oceans and melting of land-based ice, global warming is very likely contributing to the <span class="hlt">sea</span> <span class="hlt">level</span> rise observed during the 20th century. The amount by which further increases in global average temperature could <span class="hlt">affect</span> <span class="hlt">sea</span> <span class="hlt">level</span> is only known with large uncertainties due to the limited capacity of physics-based models to predict <span class="hlt">sea</span> <span class="hlt">levels</span> from global surface temperatures. Semi-empirical approaches have been implemented to estimate the statistical relationship between these two variables providing an alternative measure on which to base potentially disrupting impacts on coastal communities and ecosystems. However, only a few of these semi-empirical applications had addressed the spurious inference that is likely to be drawn when one nonstationary process is regressed on another. Furthermore, it has been shown that spurious effects are not eliminated by stationary processes when these possess strong long memory. Our results indicate that both global temperature and <span class="hlt">sea</span> <span class="hlt">level</span> indeed present the characteristics of long memory processes. Nevertheless, we find that these variables are fractionally cointegrated when <span class="hlt">sea</span>-ice extent is incorporated as an instrumental variable for temperature which in our estimations has a statistically significant positive impact on global <span class="hlt">sea</span> <span class="hlt">level</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMPP11E..07C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMPP11E..07C"><span>Revisiting Tectonic Corrections Applied to Pleistocene <span class="hlt">Sea-Level</span> Highstands</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Creveling, J. R.; Mitrovica, J. X.; Hay, C.; Austermann, J.; Kopp, R. E.</p> <p>2015-12-01</p> <p>The robustness of stratigraphic- and geomorphic-based inferences of Quaternary peak interglacial <span class="hlt">sea</span> <span class="hlt">levels</span> — and equivalent minimum continental ice volumes — depends on the accuracy with which highstand markers can be corrected for vertical tectonic displacement. For sites that preserve a Marine Isotope Stage (MIS) 5e <span class="hlt">sea-level</span> highstand marker, the customary method for estimating tectonic uplift/subsidence rate computes the difference between the local elevation of the highstand marker and a reference eustatic (i.e., global mean) MIS 5e <span class="hlt">sea-level</span> height, typically assumed to be +6 m, and then divides this height difference by the age of the highstand marker. This rate is then applied to correct the elevation of other observed <span class="hlt">sea-level</span> markers at that site for tectonic displacement. Subtracting a reference eustatic value from a local MIS 5e highstand marker elevation introduces two potentially significant errors. First, the commonly adopted peak eustatic MIS 5e <span class="hlt">sea-level</span> value (i.e., +6 m) is likely too low; recent studies concluded that MIS 5e peak eustatic <span class="hlt">sea</span> <span class="hlt">level</span> was ~6-9 m. Second, local peak MIS 5e <span class="hlt">sea</span> <span class="hlt">level</span> was not globally uniform, but instead characterized by significant departures from eustasy due to glacial isostatic adjustment (GIA) in response to successive glacial-interglacial cycles and excess polar ice-sheet melt relative to present day. We present numerical models of GIA that incorporate both of these effects in order to quantify the plausible range in error of previous tectonic corrections. We demonstrate that, even far from melting ice sheets, local peak MIS 5e <span class="hlt">sea</span> <span class="hlt">level</span> may have departed from eustasy by 2-4 m, or more. Thus, adopting an assumed reference eustatic value to estimate tectonic displacement, rather than a site-specific GIA signal, can introduce significant error in estimates of peak eustatic <span class="hlt">sea</span> <span class="hlt">level</span> (and minimum ice volumes) during Quaternary highstands (e.g., MIS 11, MIS 5c and MIS 5a).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.4718Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.4718Z"><span>Long-period <span class="hlt">sea-level</span> variations in the Mediterranean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zerbini, Susanna; Raicich, Fabio; Bruni, Sara; del Conte, Sara; Errico, Maddalena; Prati, Claudio; Santi, Efisio</p> <p>2016-04-01</p> <p>Since the beginning of its long-lasting lifetime, the Wegener initiative has devoted careful consideration to studying <span class="hlt">sea-level</span> variations/changes across the Mediterranean <span class="hlt">Sea</span>. Our study focuses on several long-period <span class="hlt">sea-level</span> time series (from end of 1800 to 2012) acquired in the Mediterranean by tide gauge stations. In general, the analysis and interpretation of these data sets can provide an important contribution to research on climate change and its impacts. We have analyzed the centennial <span class="hlt">sea-level</span> time series of six fairly well documented tide gauges. They are: Marseille, in France, Alicante in Spain, Genoa, Trieste, Venice and Marina di Ravenna (formerly Porto Corsini), in Italy. The data of the Italian stations of Marina di Ravenna and Venice clearly indicate that land subsidence is responsible for most of the observed rate of relative <span class="hlt">sea</span> <span class="hlt">level</span> rise. It is well known that, in the two areas, subsidence is caused by both natural processes and human activities. For these two stations, using <span class="hlt">levelling</span> data of benchmarks at, and/or close to, the tide gauges, and for the recent years, also GPS and InSAR height time series, modelling of the long-period non-linear behavior of subsidence was successfully accomplished. After removing the land vertical motions, the estimate of the linear long-period <span class="hlt">sea-level</span> rise at all six stations yielded remarkably consistent values, between +1,2 and +1,3 mm/yr, with associated errors ranging from ±0,2 to ±0,3 mm/yr (95% confidence interval), which also account for the statistical autocorrelation of the time series. These trends in the Mediterranean area are lower than the global mean rate of 1,7±0,2 mm/yr (1901-2010) presented by the IPCC in its 5th Assessment Report; however, they are in full agreement with a global mean <span class="hlt">sea-level</span> rise estimate, over the period 1901-1990, recently published by Hay et al. (2015, doi:10.1038/nature14093) and obtained using probabilistic techniques that combine <span class="hlt">sea-level</span> records with physics</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EnMan..57..176H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EnMan..57..176H"><span>How Much Are Floridians Willing to Pay for Protecting <span class="hlt">Sea</span> Turtles from <span class="hlt">Sea</span> <span class="hlt">Level</span> Rise?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hamed, Ahmed; Madani, Kaveh; Von Holle, Betsy; Wright, James; Milon, J. Walter; Bossick, Matthew</p> <p>2016-01-01</p> <p><span class="hlt">Sea</span> <span class="hlt">level</span> rise (SLR) is posing a great inundation risk to coastal areas. Some coastal nesting species, including <span class="hlt">sea</span> turtle species, have experienced diminished habitat from SLR. Contingent valuation method (CVM) was used in an effort to assess the economic loss impacts of SLR on <span class="hlt">sea</span> turtle nesting habitats for Florida coasts; and to elicit values of willingness to pay (WTP) of Central Florida residents to implement certain mitigation strategies, which would protect Florida's east coast <span class="hlt">sea</span> turtle nesting areas. Using the open-ended and dichotomous choice CVM, we sampled residents of two Florida communities: Cocoa Beach and Oviedo. We estimated the WTP of households from these two cities to protect <span class="hlt">sea</span> turtle habitat to be between 42 and 57 per year for 5 years. Additionally, we attempted to assess the impact of the both the respondents' demographics and their perception toward various situations on their WTP value. Findings include a negative correlation between the age of a respondent and the probability of an individual willing to pay the hypothetical WTP amount. We found that WTP of an individual was not dependent on prior knowledge of the effects of SLR on <span class="hlt">sea</span> turtle habitat. The greatest indicators of whether or not an individual was willing to pay to protect <span class="hlt">sea</span> turtle habitat were the respondents' perception regarding the trustworthiness and efficiency of the party which will implement the conservation measures and their confidence in the conservation methods used. Respondents who perceive <span class="hlt">sea</span> turtles having an effect on their life were also more likely to pay.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26319030','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26319030"><span>How Much Are Floridians Willing to Pay for Protecting <span class="hlt">Sea</span> Turtles from <span class="hlt">Sea</span> <span class="hlt">Level</span> Rise?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hamed, Ahmed; Madani, Kaveh; Von Holle, Betsy; Wright, James; Milon, J Walter; Bossick, Matthew</p> <p>2016-01-01</p> <p><span class="hlt">Sea</span> <span class="hlt">level</span> rise (SLR) is posing a great inundation risk to coastal areas. Some coastal nesting species, including <span class="hlt">sea</span> turtle species, have experienced diminished habitat from SLR. Contingent valuation method (CVM) was used in an effort to assess the economic loss impacts of SLR on <span class="hlt">sea</span> turtle nesting habitats for Florida coasts; and to elicit values of willingness to pay (WTP) of Central Florida residents to implement certain mitigation strategies, which would protect Florida's east coast <span class="hlt">sea</span> turtle nesting areas. Using the open-ended and dichotomous choice CVM, we sampled residents of two Florida communities: Cocoa Beach and Oviedo. We estimated the WTP of households from these two cities to protect <span class="hlt">sea</span> turtle habitat to be between $42 and $57 per year for 5 years. Additionally, we attempted to assess the impact of the both the respondents' demographics and their perception toward various situations on their WTP value. Findings include a negative correlation between the age of a respondent and the probability of an individual willing to pay the hypothetical WTP amount. We found that WTP of an individual was not dependent on prior knowledge of the effects of SLR on <span class="hlt">sea</span> turtle habitat. The greatest indicators of whether or not an individual was willing to pay to protect <span class="hlt">sea</span> turtle habitat were the respondents' perception regarding the trustworthiness and efficiency of the party which will implement the conservation measures and their confidence in the conservation methods used. Respondents who perceive <span class="hlt">sea</span> turtles having an effect on their life were also more likely to pay.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014cosp...40E2277N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014cosp...40E2277N"><span><span class="hlt">Sea</span> <span class="hlt">Level</span> Rise and Subsidence in the Gulf of Thailand</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Niemnil, Sommart</p> <p></p> <p>In the Thailand -EC GEO2TECDI-SONG Project we investigate the <span class="hlt">sea</span> <span class="hlt">level</span> change and vertical land motion in Thailand. First, Bangkok is situated in river delta and average height is closed to <span class="hlt">sea</span> <span class="hlt">level</span>. Second, it is subsiding due to ground water extraction. Third, it is experiencing post-seismic motion due to nearby mega thrust earthquakes and fourth, it suffers from rising of <span class="hlt">sea</span> <span class="hlt">levels</span> due to global climate change. This poses a serious threat on Thai society and economy. Before mitigation methods can be devised we aim at charting, qualifying and quantifying all contributing effects by the use of satellite altimetry, GNSS, InSAR techniques and combining results with the in situ observations like tide gauge and with geophysical modeling. Adding GPS based vertical land motion to the tide gauge <span class="hlt">sea</span> <span class="hlt">level</span> registration reveals the absolute <span class="hlt">sea</span> <span class="hlt">level</span> change, which is nicely confirmed by altimetry. We find an average absolute rise of 3.5 mm/yr + 0.7, but nears mouth of Chao Praya River (Bangkok) and the Mekong delta (Ho Chi Min City), this mounts to 4 to 5 mm/yr, faster than global average. This is reinforced when accounting for the tectonic subsidence that resulted from 2004 9.1Mw Sumatra/Andaman earthquake; from 2005 onwards we find downfall in the order of 10 mm/yr. RADARSAT InSAR analyses show subsidence rates up to 25 mm/yr at many places along coastal Bangkok.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryID=158951','PESTICIDES'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryID=158951"><span>COASTAL SENSITIVITY TO <span class="hlt">SEA</span> <span class="hlt">LEVEL</span> RISE: A FOCUS ON ...</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>Synthesis and Assessment Product 4.1 will synthesize information from the ongoing mapping efforts by federal and non-federal researchers related to the implications of rising <span class="hlt">sea</span> <span class="hlt">level</span>. It will overlay the various data layers to develop new results made possible by bringing together researchers that are otherwise working independently. Because of time, data, and resource limitations, the synthesis will focus on a contiguous portion of the U.S. coastal zone (New York to North Carolina). The report will also develop a plan for <span class="hlt">sea</span> <span class="hlt">level</span> rise research to answer the questions that are most urgent for near-term decisionmaking. This report will address the implications of <span class="hlt">sea</span> <span class="hlt">level</span> rise on three spatial scales by providing: • A literature review that puts the report within the nationwide context. • Data overlays and a state-of-the-art quantitative assessment concerning coastal elevations, shore erosion, and wetland accretion for a multi-state study area along the U.S. Atlantic Coast: New York to North Carolina. • Qualitative discussions and case studies that document in greater detail the impact of <span class="hlt">sea</span> <span class="hlt">level</span> rise on smaller areas within the mid-Atlantic study area. This report will provide information that supports the specific goal in Chapter 9 of the Strategic Plan for the Climate Change Science Program (CCSP, 2003) to analyze how coastal environmental programs can be improved to adapt to <span class="hlt">sea</span> <span class="hlt">level</span> rise while enhancing economic growth.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70182742','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70182742"><span>Cenozoic <span class="hlt">sea</span> <span class="hlt">level</span> and the rise of modern rimmed atolls</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Toomey, Michael; Ashton, Andrew; Raymo, Maureen E.; Perron, J. Taylor</p> <p>2016-01-01</p> <p><span class="hlt">Sea-level</span> records from atolls, potentially spanning the Cenozoic, have been largely overlooked, in part because the processes that control atoll form (reef accretion, carbonate dissolution, sediment transport, vertical motion) are complex and, for many islands, unconstrained on million-year timescales. Here we combine existing observations of atoll morphology and corelog stratigraphy from Enewetak Atoll with a numerical model to (1) constrain the relative rates of subsidence, dissolution and sedimentation that have shaped modern Pacific atolls and (2) construct a record of <span class="hlt">sea</span> <span class="hlt">level</span> over the past 8.5 million years. Both the stratigraphy from Enewetak Atoll (constrained by a subsidence rate of ~ 20 m/Myr) and our numerical modeling results suggest that low <span class="hlt">sea</span> <span class="hlt">levels</span> (50–125 m below present), and presumably bi-polar glaciations, occurred throughout much of the late Miocene, preceding the warmer climate of the Pliocene, when <span class="hlt">sea</span> <span class="hlt">level</span> was higher than present. Carbonate dissolution through the subsequent <span class="hlt">sea-level</span> fall that accompanied the onset of large glacial cycles in the late Pliocene, along with rapid highstand constructional reef growth, likely drove development of the rimmed atoll morphology we see today.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23379951','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23379951"><span>Impact of <span class="hlt">sea</span> <span class="hlt">level</span> rise on tide gate function.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Walsh, Sean; Miskewitz, Robert</p> <p>2013-01-01</p> <p><span class="hlt">Sea</span> <span class="hlt">level</span> rise resulting from climate change and land subsidence is expected to severely impact the duration and associated damage resulting from flooding events in tidal communities. These communities must continuously invest resources for the maintenance of existing structures and installation of new flood prevention infrastructure. Tide gates are a common flood prevention structure for low-lying communities in the tidal zone. Tide gates close during incoming tides to prevent inundation from downstream water propagating inland and open during outgoing tides to drain upland areas. Higher downstream mean <span class="hlt">sea</span> <span class="hlt">level</span> elevations reduce the effectiveness of tide gates by impacting the hydraulics of the system. This project developed a HEC-RAS and HEC-HMS model of an existing tide gate structure and its upland drainage area in the New Jersey Meadowlands to simulate the impact of rising mean <span class="hlt">sea</span> <span class="hlt">level</span> elevations on the tide gate's ability to prevent upstream flooding. Model predictions indicate that <span class="hlt">sea</span> <span class="hlt">level</span> rise will reduce the tide gate effectiveness resulting in longer lasting and deeper flood events. The results indicate that there is a critical point in the <span class="hlt">sea</span> <span class="hlt">level</span> elevation for this local area, beyond which flooding scenarios become dramatically worse and would have a significantly negative impact on the standard of living and ability to do business in one of the most densely populated areas of America.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NHESS..16.1571E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NHESS..16.1571E"><span>GIS analysis of effects of future Baltic <span class="hlt">sea</span> <span class="hlt">level</span> rise on the island of Gotland, Sweden</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ebert, Karin; Ekstedt, Karin; Jarsjö, Jerker</p> <p>2016-07-01</p> <p>Future <span class="hlt">sea</span> <span class="hlt">level</span> rise as a consequence of global warming will <span class="hlt">affect</span> the world's coastal regions. Even though the pace of <span class="hlt">sea</span> <span class="hlt">level</span> rise is not clear, the consequences will be severe and global. Commonly the effects of future <span class="hlt">sea</span> <span class="hlt">level</span> rise are investigated for relatively vulnerable development countries; however, a whole range of varying regions needs to be considered in order to improve the understanding of global consequences. In this paper we investigate consequences of future <span class="hlt">sea</span> <span class="hlt">level</span> rise along the coast of the Baltic <span class="hlt">Sea</span> island of Gotland, Sweden, with the aim to fill knowledge gaps regarding comparatively well-suited areas in developed countries. We study both the quantity of the loss of features of infrastructure, cultural, and natural value in the case of a 2 m <span class="hlt">sea</span> <span class="hlt">level</span> rise of the Baltic <span class="hlt">Sea</span> and the effects of climate change on seawater intrusion in coastal aquifers, which indirectly cause saltwater intrusion in wells. We conduct a multi-criteria risk analysis by using lidar data on land elevation and GIS-vulnerability mapping, which gives the application of distance and elevation parameters formerly unimaginable precision. We find that in case of a 2 m <span class="hlt">sea</span> <span class="hlt">level</span> rise, 3 % of the land area of Gotland, corresponding to 99 km2, will be inundated. The features most strongly <span class="hlt">affected</span> are items of touristic or nature value, including camping places, shore meadows, <span class="hlt">sea</span> stack areas, and endangered plants and species habitats. In total, 231 out of 7354 wells will be directly inundated, and the number of wells in the high-risk zone for saltwater intrusion in wells will increase considerably. Some valuable features will be irreversibly lost due to, for example, inundation of <span class="hlt">sea</span> stacks and the passing of tipping points for seawater intrusion into coastal aquifers; others might simply be moved further inland, but this requires considerable economic means and prioritization. With nature tourism being one of the main income sources of Gotland, monitoring and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.youtube.com/watch?v=dWz3s9OIIZQ','SCIGOVIMAGE-NASA'); return false;" href="http://www.youtube.com/watch?v=dWz3s9OIIZQ"><span>NASA Now: Climate Change: <span class="hlt">Sea</span> <span class="hlt">Level</span> Rise</span></a></p> <p><a target="_blank" href="http://www.nasa.gov/multimedia/videogallery/index.html">NASA Video Gallery</a></p> <p></p> <p></p> <p>Dr. Josh Willis discusses the connection between oceans and global climate change. Learn why NASA measures greenhouse gases and how we detect ocean <span class="hlt">levels</span> from space. These are crucial vital signs ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1616781N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1616781N"><span>Holocene <span class="hlt">sea-level</span> changes in the Falkland Islands</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Newton, Tom; Gehrels, Roland; Daley, Tim; Long, Antony; Bentley, Mike</p> <p>2014-05-01</p> <p>In many locations in the southern hemisphere, relative <span class="hlt">sea</span> <span class="hlt">level</span> (RSL) reached its maximum position during the middle Holocene. This highstand is used by models of glacial isostatic adjustment (GIA) to constrain the melt histories of the large ice sheets, particularly Antarctica. In this paper we present the first Holocene <span class="hlt">sea-level</span> record from the Falkland Islands (Islas Malvinas), an archipelago located on the Patagonian continental shelf about 500 km east of mainland South America at a latitude of ca. 52 degrees. Unlike coastal locations in southernmost South America, Holocene <span class="hlt">sea-level</span> data from the Falklands are not influenced by tectonics, local ice loading effects and large tidal ranges such that GIA and ice-ocean mass flux are the dominant drivers of RSL change. Our study site is a salt marsh located in Swan Inlet in East Falkland, around 50 km southwest of Stanley. This is the largest and best developed salt marsh in the Falkland Islands. Cores were collected in 2005 and 2013. Lithostratigraphic analyses were complemented by analyses of foraminifera, testate amoebae and diatoms to infer palaeoenvironments. The bedrock, a Permian black shale, is overlain by grey-brown organic salt-marsh clay, up to 90 cm thick, which, in a landward direction, is replaced by freshwater organic sediments. Overlying these units are medium-coarse sands with occasional pebbles, up to 115 cm thick, containing tidal flat foraminifera. The sandy unit is erosively overlain by a grey-brown organic salt-marsh peat which extends up to the present surface. Further away from the <span class="hlt">sea</span> this unit is predominantly of freshwater origin. Based on 13 radiocarbon dates we infer that prior to ~9.5 ka <span class="hlt">sea</span> <span class="hlt">level</span> was several metres below present. Under rising <span class="hlt">sea</span> <span class="hlt">levels</span> a salt marsh developed which was suddenly drowned around 8.4 ka, synchronous with a <span class="hlt">sea-level</span> jump known from northern hemisphere locations. Following the drowning, RSL rose to its maximum position around 7 ka, less than 0.5 m above</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014E%26PSL.399...74C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014E%26PSL.399...74C"><span>The <span class="hlt">sea-level</span> fingerprint of a Snowball Earth deglaciation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Creveling, Jessica R.; Mitrovica, Jerry X.</p> <p>2014-08-01</p> <p>Cap dolostones are thought to represent deposition from <span class="hlt">seas</span> transgressing over formerly glaciated continental margins during Marinoan Snowball deglaciation. Nevertheless, facies associations within some cap dolostones indicate that an episode of regional regression punctuated these transgressive sequence tracts. To date, inferences of <span class="hlt">sea-level</span> change during and after the Marinoan Snowball deglaciation have been interpreted using simple, qualitative arguments. In the present study, we explore the full spatio-temporal variability of <span class="hlt">sea-level</span> change during Snowball deglaciation and its aftermath using a gravitationally self-consistent theory that accounts for the deformational, gravitational and rotational perturbations to <span class="hlt">sea</span> <span class="hlt">level</span> on a viscoelastic Earth model. The theory is applied to model Marinoan Snowball deglaciation on a generalized Ediacaran paleogeography with a synthetic continental ice-sheet distribution. We find that <span class="hlt">sea-level</span> change following a synchronous, rapid (2 kyr) collapse of Snowball ice cover will exhibit significant geographic variability, including site-specific histories that are characterized by syn-deglacial <span class="hlt">sea-level</span> fall or stillstand. Moreover, some sites that experience syn-deglacial transgression will continue to experience transgression in the post-deglacial phase. Taken together, these results suggest that <span class="hlt">sea-level</span> change recorded by strata capping Snowball glaciogenic units may reflect a more complicated trajectory than previously thought, including deposition that was not limited to the deglaciation phase. These simulations, as well as others that explore the response to asynchronous melting and deglaciation phases of longer duration, demonstrate that an episode of regional regression interrupting a cap dolostone transgressive sequence tract may reflect one of several processes (or their combination): (1) near field adjustment associated with rapid local melting during an otherwise global hiatus in deglaciation; (2) post</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=average+AND+temperature&pg=3&id=EJ290512','ERIC'); return false;" href="http://eric.ed.gov/?q=average+AND+temperature&pg=3&id=EJ290512"><span>Concerns--High <span class="hlt">Sea</span> <span class="hlt">Levels</span> and Temperatures Seen Next Century.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Ryan, Paul R.</p> <p>1984-01-01</p> <p>A National Research Council committee recently concluded that atmospheric carbon dioxide <span class="hlt">levels</span> will "most likely" double by late in the next century, causing an increase in the earth's average temperature. Effects of the increase on <span class="hlt">sea</span> <span class="hlt">levels</span>, global climate, and other parameters are discussed. (JN)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70032902','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70032902"><span>Effects of <span class="hlt">sea-level</span> rise on ground water flow in a coastal aquifer system</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Masterson, J.P.; Garabedian, S.P.</p> <p>2007-01-01</p> <p>The effects of <span class="hlt">sea-level</span> rise on the depth to the fresh water/salt water interface were simulated by using a density-dependent, three-dimensional numerical ground water flow model for a simplified hypothetical fresh water lens that is similar to shallow, coastal aquifers found along the Atlantic coast of the United States. Simulations of <span class="hlt">sea-level</span> rise of 2.65 mm/year from 1929 to 2050 resulted in an increase in water <span class="hlt">levels</span> relative to a fixed datum, yet a net decrease in water <span class="hlt">levels</span> relative to the increased <span class="hlt">sea-level</span> position. The net decrease in water <span class="hlt">levels</span> was much greater near a gaining stream than farther from the stream. The difference in the change in water <span class="hlt">levels</span> is attributed to the dampening effect of the stream on water <span class="hlt">level</span> changes in response to <span class="hlt">sea-level</span> rise. In response to the decreased water <span class="hlt">level</span> altitudes relative to local <span class="hlt">sea</span> <span class="hlt">level</span>, the depth to the fresh water/salt water interface decreased. This reduction in the thickness of the fresh water lens varied throughout the aquifer and was greatly <span class="hlt">affected</span> by proximity to a ground water fed stream and whether the stream was tidally influenced. Away from the stream, the thickness of the fresh water lens decreased by about 2% from 1929 to 2050, whereas the fresh water lens thickness decreased by about 22% to 31% for the same period near the stream, depending on whether the stream was tidally influenced. The difference in the change in the fresh water/salt water interface position is controlled by the difference in the net decline in water <span class="hlt">levels</span> relative to local <span class="hlt">sea</span> <span class="hlt">level</span>. ?? 2007 National Ground Water Association.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17..445M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17..445M"><span>Tracking multidecadal trends in <span class="hlt">sea</span> <span class="hlt">level</span> using coral microatolls</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Majewski, Jedrzej; Pham, Dat; Meltzner, Aron; Switzer, Adam; Horton, Benjamin; Heng, Shu Yun; Warrick, David</p> <p>2015-04-01</p> <p>Tracking multidecadal trends in <span class="hlt">sea</span> <span class="hlt">level</span> using coral microatolls Jędrzej M. Majewski 1, Dat T. Pham1, Aron J. Meltzner 1, Adam D. Switzer 1, Benjamin P. Horton2, Shu Yun Heng1, David Warrick3, 1 Earth Observatory of Singapore, Nanyang Technological University, Singapore 2 Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, NJ, USA 3 Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA Coral microatolls can be used to study relative <span class="hlt">sea-level</span> change at multidecadal timescales associated with vertical land movements, climate induced <span class="hlt">sea-level</span> rise and other oceanographic phenomena such as the El Niño/Southern Oscillation (ENSO) or Indian Ocean Dipole (IOD) with the assumption that the highest <span class="hlt">level</span> of survival (HLS) of coral microatolls track <span class="hlt">sea</span> <span class="hlt">level</span> over the course of their lifetimes. In this study we compare microatoll records covering from as early as 1883 through 2013, from two sites in Indonesia, with long records (>20 years) from proximal tide gauges, satellite altimetry, and other <span class="hlt">sea-level</span> reconstructions. We compared the HLS time series derived from open-ocean and moated (or ponded) microatolls on tectonically stable Belitung Island and a potentially tectonically active setting in Mapur Island, with <span class="hlt">sea-level</span> reconstructions for 1950-2011. The <span class="hlt">sea-level</span> reconstructions are based on ground and satellite measurements, combining a tide model with the Estimating the Circulation and Climate of the Ocean (ECCO) model. Our results confirm that open-ocean microatolls do track low water <span class="hlt">levels</span> at multi decadal time scales and can be used as a proxy for relative <span class="hlt">sea</span> <span class="hlt">level</span> (RSL) over time. However, microatolls that are even partially moated are unsuitable and do not track RSL; rather, their growth patterns likely reflect changes in the elevation of the sill of the local pond, as reported by earlier authors. Our ongoing efforts will include an attempt to recognize similarities in moated</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA608977','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA608977"><span>USACE Extreme <span class="hlt">Sea</span> <span class="hlt">Levels</span> Advice on Guidance on Procedures to Evaluate and Adapt to Changes in Mean and Extreme <span class="hlt">Sea</span> <span class="hlt">Levels</span>.</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2014-09-09</p> <p>influences of changes in extreme <span class="hlt">sea</span> <span class="hlt">levels</span> as they <span class="hlt">affect</span> the four mission areas of USACE: storm damage reduction, flood risk mitigation, ecosystems...winds and surface pressure can occur on the scale of the inundation area under investigation, cyclonic climatologies and more sophisticated inundation...Federal and State agencies (particularly the Bureau of Meteorology) providing forecast data (e.g. DIPNR, 2005, Appendix N). In more developed areas of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.G43B1052B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.G43B1052B"><span>Relative and Geocentric <span class="hlt">Sea</span> <span class="hlt">Level</span> Rise Along the U.S. West Coast</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Burgette, R. J.; Watson, C. S.</p> <p>2015-12-01</p> <p>The rate of <span class="hlt">sea</span> <span class="hlt">level</span> change relative to the land along the West Coast of the U.S. varies over a range of +5 to -2 mm/yr, as observed across the set of long-running tide gauges. We analyze tide gauge data in a network approach that accounts for temporal and spatial correlations in the time series of water <span class="hlt">levels</span> observed at the stations. This analysis yields a set of rate estimates and realistic uncertainties that are minimally <span class="hlt">affected</span> by varying durations of observations. The analysis has the greatest impact for tide gauges with short records, as the adjusted rate uncertainties for 2 to 3 decade duration tide gauges approach those estimated from unadjusted century-scale time series. We explore the sources of the wide range of observed relative <span class="hlt">sea</span> <span class="hlt">level</span> rates through comparison with: 1) estimated vertical deformation rates derived from repeated <span class="hlt">leveling</span> and GPS, 2) relative <span class="hlt">sea</span> <span class="hlt">level</span> change predicted from models of glacial isostatic adjustment, and 3) geocentric <span class="hlt">sea</span> <span class="hlt">level</span> rates estimated from satellite altimetry and century-scale reconstructions. Tectonic deformation is the dominant signal in the relative <span class="hlt">sea</span> <span class="hlt">level</span> rates along the Cascadia portion of the coast, and is consistent with along-strike variation in locking behavior on the plate interface. Rates of vertical motion are lower along the transform portion of the plate boundary and include anthropogenic effects, but there are significant tectonic signals, particularly in the western Transverse Ranges of California where the crust is shortening across reverse faults. Preliminary analysis of different strategies of estimating the magnitude of geocentric <span class="hlt">sea</span> <span class="hlt">level</span> rise suggest significant discrepancies between approaches. We will examine the implications of these discrepancies for understanding the process of regional geocentric <span class="hlt">sea</span> <span class="hlt">level</span> rise in the northeastern Pacific Ocean, and associated projected impacts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011EOSTr..92..273F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011EOSTr..92..273F"><span>Rising <span class="hlt">sea</span> <span class="hlt">level</span> may cause decline of fringing coral reefs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Field, Michael E.; Ogston, Andrea S.; Storlazzi, Curt D.</p> <p>2011-08-01</p> <p>Coral reefs are major marine ecosystems and critical resources for marine diversity and fisheries. These ecosystems are widely recognized to be at risk from a number of stressors, and added to those in the past several decades is climate change due to anthropogenically driven increases in atmospheric concentrations of greenhouse gases. Most threatening to most coral reefs are elevated <span class="hlt">sea</span> surface temperatures and increased ocean acidity [e.g., Kleypas et al., 1999; Hoegh-Guldberg et al., 2007], but <span class="hlt">sea</span> <span class="hlt">level</span> rise, another consequence of climate change, is also likely to increase sedimentary processes that potentially interfere with photosynthesis, feeding, recruitment, and other key physiological processes (Figure 1). Anderson et al. [2010] argue compellingly that potential hazardous impacts to coastlines from 21st-century <span class="hlt">sea</span> <span class="hlt">level</span> rise are greatly underestimated, particularly because of the rapid rate of rise. The Intergovernmental Panel on Climate Change estimates that <span class="hlt">sea</span> <span class="hlt">level</span> will rise in the coming century (1990-2090) by 2.2-4.4 millimeters per year, when projected with little contribution from melting ice [Meehl et al., 2007]. New studies indicate that rapid melting of land ice could substantially increase the rate of <span class="hlt">sea</span> <span class="hlt">level</span> rise [Grinsted et al., 2009; Milne et al., 2009].</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70043010','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70043010"><span>Rising <span class="hlt">sea</span> <span class="hlt">level</span> may cause decline of fringing coral reefs</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Field, Michael E.; Ogston, Andrea S.; Storlazzi, Curt D.</p> <p>2011-01-01</p> <p>Coral reefs are major marine ecosystems and critical resources for marine diversity and fisheries. These ecosystems are widely recognized to be at risk from a number of stressors, and added to those in the past several decades is climate change due to anthropogenically driven increases in atmospheric concentrations of greenhouse gases. Most threatening to most coral reefs are elevated <span class="hlt">sea</span> surface temperatures and increased ocean acidity [e.g., Kleypas et al., 1999; Hoegh-Guldberg et al., 2007], but <span class="hlt">sea</span> <span class="hlt">level</span> rise, another consequence of climate change, is also likely to increase sedimentary processes that potentially interfere with photosynthesis, feeding, recruitment, and other key physiological processes (Figure 1). Anderson et al. [2010] argue compellingly that potential hazardous impacts to coastlines from 21st-century <span class="hlt">sea</span> <span class="hlt">level</span> rise are greatly underestimated, particularly because of the rapid rate of rise. The Intergovernmental Panel on Climate Change estimates that <span class="hlt">sea</span> <span class="hlt">level</span> will rise in the coming century (1990–2090) by 2.2–4.4 millimeters per year, when projected with little contribution from melting ice [Meehl et al., 2007]. New studies indicate that rapid melting of land ice could substantially increase the rate of <span class="hlt">sea</span> <span class="hlt">level</span> rise [Grinsted et al., 2009; Milne et al., 2009].</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70036289','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70036289"><span>Rising <span class="hlt">sea</span> <span class="hlt">level</span> may cause decline of fringing coral reefs</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Field, M.E.; Ogston, A.S.; Storlazzi, C.D.</p> <p>2011-01-01</p> <p>Coral reefs are major marine ecosystems and critical resources for marine diversity and fisheries. These ecosystems are widely recognized to be at risk from a number of stressors, and added to those in the past several decades is climate change due to anthropogenically driven increases in atmospheric concentrations of greenhouse gases. Most threatening to most coral reefs are elevated <span class="hlt">sea</span> surface temperatures and increased ocean acidity [e.g., Kleypas et al., 1999; Hoegh-Guldberg et al., 2007], but <span class="hlt">sea</span> <span class="hlt">level</span> rise, another consequence of climate change, is also likely to increase sedimentary processes that potentially interfere with photosynthesis, feeding, recruitment, and other key physiological processes (Figure 1). Anderson et al. [2010] argue compellingly that potential hazardous impacts to coastlines from 21st-century <span class="hlt">sea</span> <span class="hlt">level</span> rise are greatly underestimated, particularly because of the rapid rate of rise. The Intergovernmental Panel on Climate Change estimates that <span class="hlt">sea</span> <span class="hlt">level</span> will rise in the coming century (1990-2090) by 2.2-4.4 millimeters per year, when projected with little contribution from melting ice [Meehl et al., 2007]. New studies indicate that rapid melting of land ice could substantially increase the rate of <span class="hlt">sea</span> <span class="hlt">level</span> rise [Grinsted et al., 2009; Milne et al., 2009].</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Rising+AND+sea+AND+levels&id=EJ389555','ERIC'); return false;" href="http://eric.ed.gov/?q=Rising+AND+sea+AND+levels&id=EJ389555"><span>The Significance of Rising <span class="hlt">Sea</span> <span class="hlt">Levels</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Conway, Gregory J.</p> <p>1989-01-01</p> <p>Describes an activity in which students graph changes in tides and ocean <span class="hlt">levels</span> over a period in order to obtain a visual representation of the changes taking place and their effects upon the Earth. Provides questions for students to answer after construction of the graphs. (RT)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoRL..43.6478W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoRL..43.6478W"><span>A new perspective on global mean <span class="hlt">sea</span> <span class="hlt">level</span> (GMSL) acceleration</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Watson, Phil J.</p> <p>2016-06-01</p> <p>The vast body of contemporary climate change science is largely underpinned by the premise of a measured acceleration from anthropogenic forcings evident in key climate change proxies -- greenhouse gas emissions, temperature, and mean <span class="hlt">sea</span> <span class="hlt">level</span>. By virtue, over recent years, the issue of whether or not there is a measurable acceleration in global mean <span class="hlt">sea</span> <span class="hlt">level</span> has resulted in fierce, widespread professional, social, and political debate. Attempts to measure acceleration in global mean <span class="hlt">sea</span> <span class="hlt">level</span> (GMSL) have often used comparatively crude analysis techniques providing little temporal instruction on these key questions. This work proposes improved techniques to measure real-time velocity and acceleration based on five GMSL reconstructions spanning the time frame from 1807 to 2014 with substantially improved temporal resolution. While this analysis highlights key differences between the respective reconstructions, there is now more robust, convincing evidence of recent acceleration in the trend of GMSL.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950046393&hterms=Barometers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DBarometers','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950046393&hterms=Barometers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DBarometers"><span>Geosat observations of <span class="hlt">sea</span> <span class="hlt">level</span> response to barometric pressure forcing</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hoar, Timothy J.; Wilson, Clark R.</p> <p>1994-01-01</p> <p>Altimeter and <span class="hlt">sea</span> <span class="hlt">level</span> pressure data from the Geosat mission are analyzed for evidence of inverted barometer responses of <span class="hlt">sea</span> <span class="hlt">level</span> to atmospheric pressure forcing. Estimates of the inverted barometer coefficient are given for a variety of geographic regions and time scales using various orbit error removal strategies. There is some sensitivity to the orbit error removal method, but the estimated coefficients show a clear latitudinal dependence and are generally between -0.5 cm/mbar and -0.9 cm/mbar. The southern oceans respond slightly more like an inverted barometer than the northern oceans for similar latitudes. The regression exhibits significant geographic variability, particularly near major circulation features and in the northern hemisphere. The results suggest that the inverted barometer approximation is resonable over much of the oceans, but that some <span class="hlt">sea</span> <span class="hlt">level</span> variability may be correlated with barometric pressure by means other than the inverted barometer effect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19770059848&hterms=tsunami&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dtsunami','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19770059848&hterms=tsunami&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dtsunami"><span>A <span class="hlt">sea-level</span> recorder for tectonic studies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bilham, R.</p> <p>1977-01-01</p> <p>In the past tide gauges have provided valuable information concerning the vertical ground deformation associated with major earthquakes. Although tide-gauge data contains numerous sources of noise, a spacing of less than 40 km between gauges is indicated for a useful study of dilatant behavior, and a spacing of less than 80 km may be adequate for the study of crustal downwarping in island arcs. An inexpensive tide gauge which is designed to provide a continuous record of <span class="hlt">sea</span> <span class="hlt">level</span> with a measurement precision of 1 mm is described. Hydraulic filtering is incorporated into the instrument to attenuate daily tides relative to longer period variations of <span class="hlt">sea</span> <span class="hlt">level</span>. The instrument is designed to operate from flashlight batteries for a year unattended and to withstand temporary submersion as might be caused by tsunamis. Several of these <span class="hlt">sea-level</span> recorders have been installed in seismic gaps in the Aleutians and in the Caribbean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017E%26ES...52a2065X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017E%26ES...52a2065X"><span>Spatial-temporal analysis of <span class="hlt">sea</span> <span class="hlt">level</span> changes in China <span class="hlt">seas</span> and neighboring oceans by merged altimeter data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xu, Yao; Zhou, Bin; Yu, Zhifeng; Lei, Hui; Sun, Jiamin; Zhu, Xingrui; Liu, Congjin</p> <p>2017-01-01</p> <p>The knowledge of <span class="hlt">sea</span> <span class="hlt">level</span> changes is critical important for social, economic and scientific development in coastal areas. Satellite altimeter makes it possible to observe long term and large scale dynamic changes in the ocean, contiguous shelf <span class="hlt">seas</span> and coastal zone. In this paper, 1993-2015 altimeter data of Topex/Poseidon and its follow-on missions is used to get a time serious of continuous and homogeneous <span class="hlt">sea</span> <span class="hlt">level</span> anomaly gridding product. The <span class="hlt">sea</span> <span class="hlt">level</span> rising rate is 0.39 cm/yr in China <span class="hlt">Seas</span> and the neighboring oceans, 0.37 cm/yr in the Bo and Yellow <span class="hlt">Sea</span>, 0.29 cm/yr in the East China <span class="hlt">Sea</span> and 0.40 cm/yr in the South China <span class="hlt">Sea</span>. The mean <span class="hlt">sea</span> <span class="hlt">level</span> and its rising rate are spatial-temporal non-homogeneous. The mean <span class="hlt">sea</span> <span class="hlt">level</span> shows opposite characteristics in coastal <span class="hlt">seas</span> versus open oceans. The Bo and Yellow <span class="hlt">Sea</span> has the most significant seasonal variability. The results are consistent with in situ data observation by the Nation Ocean Agency of China. The coefficient of variability model is introduced to describe the spatial-temporal variability. Results show that the variability in coastal <span class="hlt">seas</span> is stronger than that in open oceans, especially the <span class="hlt">seas</span> off the entrance area of the river, indicating that the validation of altimeter data is less reasonable in these <span class="hlt">seas</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16..601P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16..601P"><span>The imprint of <span class="hlt">sea-level</span> changes in the Southeastern Iberian continental shelf, Western Mediterranean <span class="hlt">Sea</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pinna, Andrea; Lastras, Galderic; Acosta, Juan; Muñoz, Araceli; Canals, Miquel</p> <p>2014-05-01</p> <p>A detailed morphologic analysis of the Southeastern Iberian continental shelf, Western Mediterranean <span class="hlt">Sea</span>, between the Mar Menor and the Gulf of Almería, based on swath bathymetry data, has revealed a number of seafloor features that we attribute to the imprint of <span class="hlt">sea-level</span> changes since the last glacial maximum. The continental shelf has been divided in four different domains with contrasting characteristics: the Mar Menor sector, the Mazarrón and Vera sector, the Gata Cape shelf and the Gulf of Almería shelf. The Mar Menor sector displays an up to 40 km wide shelf with a very low slope gradient, which contrasts with the Mazarrón and Vera shelf, with a width ranging between 0.4 and 5 km, severely incised by the different branches of the Garrucha submarine canyon. On each of these sectors, a variety of morphologies such as crests and escarpments have been identified. Most of these crests and escarpments can be followed for distances exceeding 15 km, and are located at constant, characteristic water depths. We interpret these structures as the result of relatively short-lived <span class="hlt">sea-level</span> still-stands and thus as palaeo-coastlines. Taking into account subsidence, we have correlated their bathymetric position with published post-MIS-5 Mediterranean <span class="hlt">sea-level</span> evolution curves, allowing the attribution of an approximate age for each interpreted palaeo-coastline. The last <span class="hlt">sea-level</span> regression is partially registered in the smooth Mar Menor shelf, where different crests and escarpments are cut by a LGM palaeo-channel, whereas all the sectors display structures related to the last <span class="hlt">sea-level</span> transgression. The continuity of these structures along all the sectors has allowed reconstructing the evolution of the coastline during the last <span class="hlt">sea-level</span> transgression, and thus inferring the palaeo-landscape of this sector of the Southeastern Iberian coast at different stages since 18 ka BP until the present.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMGC21C1101K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMGC21C1101K"><span>Attribution of Annual Maximum <span class="hlt">Sea</span> <span class="hlt">Levels</span> to Tropical Cyclones</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khouakhi, A.; Villarini, G.</p> <p>2015-12-01</p> <p>Tropical cyclones (TCs) can cause catastrophic storm surges with major social, economic, and ecological impacts in coastal areas. Understanding the contribution of TCs to extreme <span class="hlt">sea</span> <span class="hlt">levels</span> is therefore essential. In this work we examine the contribution of TCs to annual maximum <span class="hlt">sea</span> <span class="hlt">levels</span> at the global scale, including potential climate controls and temporal changes. Complete global coverage (1842-2014) of historical 6-hour best track TC records are obtained from the International Best Track Archive for Climate Stewardship (IBTrACS) data set. Hourly tide gauge data are obtained from the Joint Archive for <span class="hlt">Sea</span> <span class="hlt">Level</span> Research Quality Data Set. There are 177 tide gauge stations with at least 25 complete years of data between 1970 and 2014 (a complete year is defined as having more than 90% of all the hourly measurements in a year). We associate an annual maximum <span class="hlt">sea</span> <span class="hlt">level</span> at a given station with a TC if the center of circulation of the storm passed within a certain distance from the station within a given time window. Spatial and temporal sensitivity analyses are performed with varying time windows (6h, 12h) and buffer zones (200km and 500km) around the tide gauge stations. Results highlight large regional differences, with some locations experiencing almost ¾ of their annual maxima during the passage of a TC. The attribution of annual maximum <span class="hlt">sea</span> <span class="hlt">level</span> to TCs is particularly high along the coastal areas of the eastern United States, the Gulf of Mexico, China, Japan, Taiwan and Western Australia. Further analyses will examine the role played by El Niño - Southern Oscillation and the potential temporal changes in TC contributions to annual maximum <span class="hlt">sea</span> <span class="hlt">levels</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMED41A0715D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMED41A0715D"><span><span class="hlt">Sea-Level</span> Rise and Flood Potential along the California Coast</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Delepine, Q.; Leung, C.</p> <p>2013-12-01</p> <p><span class="hlt">Sea-level</span> rise is becoming an ever-increasing problem in California. <span class="hlt">Sea-level</span> is expected to rise significantly in the next 100 years, which will raise flood elevations in coastal communities. This will be an issue for private homeowners, businesses, and the state. One study suggests that Venice Beach could lose a total of at least $440 million in tourism spending and tax dollars from flooding and beach erosion if <span class="hlt">sea</span> <span class="hlt">level</span> rises 1.4 m by 2100. In addition, several airports, such as San Francisco International Airport, are located in coastal regions that have flooded in the past and will likely be flooded again in the next 30 years, but <span class="hlt">sea-level</span> rise is expected to worsen the effects of flooding in the coming decades It is vital for coastal communities to understand the risks associated with <span class="hlt">sea-level</span> rise so that they can plan to adapt to it. By obtaining accurate LiDAR elevation data from the NOAA Digital Coast Website (http://csc.noaa.gov/dataviewer/?keyword=lidar#), we can create flood maps to simulate <span class="hlt">sea</span> <span class="hlt">level</span> rise and flooding. The data are uploaded to ArcGIS and contour lines are added for different elevations that represent future coastlines during 100-year flooding. The following variables are used to create the maps: 1. High-resolution land surface elevation data - obtained from NOAA 2. Local mean high water <span class="hlt">level</span> - from USGS 3. Local 100-year flood water <span class="hlt">level</span> - from the Pacific Institute 4. <span class="hlt">Sea-level</span> rise projections for different future dates (2030, 2050, and 2100) - from the National Research Council The values from the last three categories are added to represent <span class="hlt">sea-level</span> rise plus 100-year flooding. These values are used to make the contour lines that represent the projected flood elevations, which are then exported as KML files, which can be opened in Google Earth. Once these KML files are made available to the public, coastal communities will gain an improved understanding of how flooding and <span class="hlt">sea-level</span> rise might <span class="hlt">affect</span> them in the future</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1810735V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1810735V"><span>Uncertainties in <span class="hlt">sea</span> <span class="hlt">level</span> projections on twenty-year timescales</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vinogradova, Nadya; Davis, James; Landerer, Felix; Little, Chris</p> <p>2016-04-01</p> <p>Regional decadal changes in <span class="hlt">sea</span> <span class="hlt">level</span> are governed by various processes, including ocean dynamics, gravitational and solid earth responses, mass loss of continental ice, and other local coastal processes. In order to improve predictions and physical attribution in decadal <span class="hlt">sea</span> <span class="hlt">level</span> trends, the uncertainties of each processes must be reflected in the <span class="hlt">sea</span> <span class="hlt">level</span> calculations. Here we explore uncertainties in predictions of the decadal and bi-decadal changes in regional <span class="hlt">sea</span> <span class="hlt">level</span> induced by the changes in ocean dynamics and associated redistribution of heat and freshwater (often referred to as dynamic <span class="hlt">sea</span> <span class="hlt">level</span>). Such predictions are typically based on the solutions from coupled atmospheric and oceanic general circulation models, including a suite of climate models participating in phase 5 of the Coupled Model Intercompasion Project (CMIP5). Designed to simulate long-term ocean variability in response to warming climate due to increasing green-house gas concentration ("forced" response), CMIP5 are deficient in simulating variability at shorter time scales. In contrast, global observations of <span class="hlt">sea</span> <span class="hlt">level</span> are available during a relatively short time span (e.g., twenty-year altimetry records), and are dominated by an "unforced" variability that occurs freely (internally) within the climate system. This makes it challenging to examine how well observations compare with model simulations. Therefore, here we focus on patterns and spatial characteristics of projected twenty-year trends in dynamic <span class="hlt">sea</span> <span class="hlt">level</span>. Based on the ensemble of CMIP5 models, each comprising a 240-year run, we compute an envelope of twenty-year rates, and analyze the spread and spatial relationship among predicted rates. An ensemble root-mean-square average exhibits large-scale spatial patterns, with the largest uncertainties found over mid and high latitudes that could be attributed to the changes in wind patterns and buoyancy forcing. To understand and parameterize spatial characteristics of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24305147','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24305147"><span>Coastal flooding by tropical cyclones and <span class="hlt">sea-level</span> rise.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Woodruff, Jonathan D; Irish, Jennifer L; Camargo, Suzana J</p> <p>2013-12-05</p> <p>The future impacts of climate change on landfalling tropical cyclones are unclear. Regardless of this uncertainty, flooding by tropical cyclones will increase as a result of accelerated <span class="hlt">sea-level</span> rise. Under similar rates of rapid <span class="hlt">sea-level</span> rise during the early Holocene epoch most low-lying sedimentary coastlines were generally much less resilient to storm impacts. Society must learn to live with a rapidly evolving shoreline that is increasingly prone to flooding from tropical cyclones. These impacts can be mitigated partly with adaptive strategies, which include careful stewardship of sediments and reductions in human-induced land subsidence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1172858','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1172858"><span>Land-ice modeling for <span class="hlt">sea-level</span> prediction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lipscomb, William H</p> <p>2010-06-11</p> <p>There has been major progress in ice sheet modeling since IPCC AR4. We will soon have efficient higherorder ice sheet models that can run at ",1 km resolution for entire ice sheets, either standalone or coupled to GeMs. These models should significantly reduce uncertainties in <span class="hlt">sea-level</span> predictions. However, the least certain and potentially greatest contributions to 21st century <span class="hlt">sea-level</span> rise may come from ice-ocean interactions, especially in West Antarctica. This is a coupled modeling problem that requires collaboration among ice, ocean and atmosphere modelers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900040662&hterms=sea+level+rise&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsea%2Blevel%2Brise','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900040662&hterms=sea+level+rise&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsea%2Blevel%2Brise"><span>Spectroscopic analysis of global tide gauge <span class="hlt">sea</span> <span class="hlt">level</span> data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Trupin, A.; Wahr, J.</p> <p>1990-01-01</p> <p>Yearly and monthly global tide-gage <span class="hlt">sea-level</span> data are fitted to numerically generated tidal data in order to search for the 18.6-yr lunar nodal tide and 14-month pole tide. Both of these tides are clearly evident, with amplitudes and phases that are consistent with a global equilibrium response. The ocean's response to atmospheric pressure is studied with the least-squares fit technique. Consideration is given to the global rise in <span class="hlt">sea</span> <span class="hlt">level</span>, the effects of postglacial rebound, and the possible causes of the enhanced pole tides in the North <span class="hlt">Sea</span>, the Baltic <span class="hlt">Sea</span>, and the Gulf of Bothnia. The results support O'Connor's (1986) suggestion that the enhanced pole tide in these regions is due to meteorological forcing rather than a basin-scale resonance. Also, the global average of the tide-gage data show an increase in <span class="hlt">sea</span> <span class="hlt">level</span> over tha last 80 yr of between 1.1 and 1.9 mm/yr.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.1721S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.1721S"><span>Mean and extreme <span class="hlt">sea</span> <span class="hlt">level</span> changes in the southwestern Baltic <span class="hlt">Sea</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schmidt, Jessica; Patzke, Justus; Dangendorf, Sönke; Arns, Arne; Jensen, Jürgen; Fröhle, Peter</p> <p>2016-04-01</p> <p>In this contribution an overview over the BMBF project AMSeL_Ostsee (2015-2018) for the assessment of mean and extreme <span class="hlt">sea</span> <span class="hlt">level</span> changes over the past 150 years in the southwestern Baltic <span class="hlt">Sea</span> is presented. We compile several high resolution tide gauge records provided by the Water and Shipping Administration (WSV) along the German Baltic <span class="hlt">Sea</span> coastline and merge them in internationally available data bases (UHSLC, PSMSL, and data officially available at national authorities). In addition, we make efforts in digitizing historical records to expand the number of available data sets in this complex and vulnerable coastal region. To separate absolute from relative long-term changes in <span class="hlt">sea</span> <span class="hlt">level</span> the vertical land motion (VLM) at specific sites is assessed. Possible sources of VLM are independently assessed by using different state-of-the-art approaches, that is: Glacial Isostatic Adjustment (GIA) modelled by viscoelastic Earth models, GPS derived VLM, and the difference between tide gauge and nearby satellite altimetry. The VLM corrected tide gauge records are further assessed for linear and non-linear trends as well as possible acceleration/deceleration patterns by applying advanced time series models such as Singular System Analysis (SSA) combined with a Monte-Carlo-Autoregressive-Padding approach (Wahl et al., 2010). These trend assessments are applied to mean and extreme <span class="hlt">sea</span> <span class="hlt">levels</span> independently to prove whether observed changes in extremes are either due to an underlying trend on mean <span class="hlt">sea</span> <span class="hlt">levels</span> or changes in storminess. References: Wahl, T., Jensen, J., Frank, T. (2011): On analysing <span class="hlt">sea</span> <span class="hlt">level</span> rise in the German Bight since 1844, NHESS, 10, 171-179.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22946376','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22946376"><span>Vitamin A deficiency and hepatic retinol <span class="hlt">levels</span> in <span class="hlt">sea</span> otters, Enhydra lutris.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>St Leger, Judy A; Righton, Alison L; Nilson, Erika M; Fascetti, Andrea J; Miller, Melissa A; Tuomi, Pamela A; Goertz, Caroline E C; Puschner, Birgit</p> <p>2011-03-01</p> <p>Vitamin A deficiency has rarely been reported in captive or free-ranging wildlife species. Necropsy findings in two captively housed southern <span class="hlt">sea</span> otters (Enhydra lutris nereis) included irregular thickening of the calvaria characterized by diffuse hyperostoses on the internal surface. One animal also had moderate squamous metaplasia of the seromucinous glands of the nose. There was no measurable retinol in the liver of either <span class="hlt">sea</span> otter. For comparison, hepatic retinol concentration was determined for 23 deceased free-ranging southern and northern (Enhydra lutris kenyoni) <span class="hlt">sea</span> otters from California and Alaska. Free-ranging otters were found to have similar hepatic retinol concentrations (316 +/- 245 mg/kg wet weight) regardless of their location and subspecies. All of these values were significantly higher than the <span class="hlt">levels</span> in the <span class="hlt">affected</span> animals. Consumption of a diet with very low vitamin A concentrations and noncompliance in daily supplementation are hypothesized as the causes of vitamin A deficiency in these two <span class="hlt">sea</span> otters.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010QSRv...29.1432T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010QSRv...29.1432T"><span>Infilling and flooding of the Mekong River incised valley during deglacial <span class="hlt">sea-level</span> rise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tjallingii, Rik; Stattegger, Karl; Wetzel, Andreas; Van Phach, Phung</p> <p>2010-06-01</p> <p>The abrupt transition from fluvial to marine deposition of incised-valley-fill sediments retrieved from the southeast Vietnamese shelf, accurately records the postglacial transgression after 14 ka before present (BP). Valley-filling sediments consist of fluvial mud, whereas sedimentation after the transgression is characterized by shallow-marine carbonate sands. This change in sediment composition is accurately marked in high-resolution X-ray fluorescence (XRF) core scanning records. Rapid aggradation of fluvial sediments at the river mouth nearly completely filled the Mekong incised valley prior to flooding. However, accumulation rates strongly reduced in the valley after the river-mouth system flooded and stepped back. This also <span class="hlt">affected</span> the sediment supply to deeper parts of the southeast Vietnamese shelf. Comparison of the Mekong valley-filling with the East Asian <span class="hlt">sea-level</span> history of sub- and inter-tidal sediment records shows that the transgressive surface preserved in the incised-valley-fill records is a robust <span class="hlt">sea-level</span> indicator. The valley was nearly completely filled with fluvial sediments between 13.0 and 9.5 ka BP when <span class="hlt">sea-level</span> rose rather constantly with approximately 10 mm/yr, as indicated by the East Asian <span class="hlt">sea-level</span> record. At shallower parts of the shelf, significant sediment reworking and the establishment of estuarine conditions at the final stage of infilling complicates accurate dating of the transgressive surface. Nevertheless, incised-valley-fill records and land-based drill sites indicate a vast and rapid flooding of the shelf from the location of the modern Vietnamese coastline to the Cambodian lowlands between 9.5 ka and 8.5 ka BP. Fast flooding of this part of the shelf is related with the low shelf gradient and a strong acceleration of the East Asian <span class="hlt">sea-level</span> rise from 34 to 9 meter below modern <span class="hlt">sea</span> <span class="hlt">level</span> (mbsl) corresponding to the <span class="hlt">sea-level</span> jump of melt water pulse (MWP) 1C.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/35697','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/35697"><span>Response of wetlands to rising <span class="hlt">sea</span> <span class="hlt">level</span> in the lower coastal plain of North Carolina</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Moorhead, K.K.; Brinson, M.M.</p> <p>1995-02-01</p> <p>Most of the coastal wetlands of the South Atlantic region of the United States are expected to diminish in size in response to increasing human population growth and accelerating rates of rising <span class="hlt">sea</span> <span class="hlt">level</span>. after examination of the distribution of wetlands, elevation contours, estimates of surface slope, soil types, and peat deposits on the peninsula, current models were considered unsuited for wetlands of the Albemarle-Pamlico peninsula of North Carolina. Some unusual features of this peninsula are low elevation (56% of total area <1.5 m), extensive coverage by wetlands (53%) and hydric soils (90%), negligible slopes of the land surface, virtual absence of tides, and lack of abundant sources of sediment. In the process of reconstructing how past rises in <span class="hlt">sea</span> <span class="hlt">level</span> most likely led to present conditions, it became apparent that vertical accretion of peat in situ is largely responsible for landscape features in areas where elevations are lowest. Were it not for these deposits, the land surface area of the peninsula would be decreasing relative to <span class="hlt">sea</span> <span class="hlt">level</span>. This situation contrasts sharply with areas in the eastern United States fringed by tidal marshes, which are undergoing overland migration at a rate dictated by landward slope and the rate of rising <span class="hlt">sea</span> <span class="hlt">level</span>. If the rate of <span class="hlt">sea</span> <span class="hlt">level</span> rise accelerates, it is doubtful if vertical accretion rates of peat can prevent submergence of extensive areas of wetlands in the Albemarle-Pamlico peninsula. Land use and drainage in the lowest elevations of the peninsula are currently being <span class="hlt">affected</span> by <span class="hlt">sea</span> <span class="hlt">level</span>. Future land management of the peninsula will be constrained by potential landscape changes as a result of rising <span class="hlt">sea</span> <span class="hlt">level</span>. 28 refs., 6 figs., 5 tabs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19936799','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19936799"><span>Temperature, comfort and pollution <span class="hlt">levels</span> during heat waves and the role of <span class="hlt">sea</span> breeze.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Papanastasiou, Dimitris K; Melas, Dimitris; Bartzanas, Thomas; Kittas, Constantinos</p> <p>2010-05-01</p> <p>During the summer of 2007 several Greek regions suffered periods of extreme heat, with midday temperatures of over 40 degrees C on several consecutive days. High temperatures were also recorded on the east coast of central Greece, where a complex <span class="hlt">sea</span> breeze circulation system frequently develops. The more intense events occurred at the end of June and July. The highest temperatures were observed on 26 June and 25 July, while the <span class="hlt">sea</span> breeze developed only on 25 July. Meteorological data collected at two sites-a coastal urban location and an inland suburban site that is not reached by the <span class="hlt">sea</span> breeze flow-as well as pollution data collected at the urban site, were analysed in order to investigate the relationship between <span class="hlt">sea</span> breeze development and the prevailing environmental conditions during these two heat wave events. The analysis revealed that <span class="hlt">sea</span> breeze development <span class="hlt">affects</span> temperature and pollution <span class="hlt">levels</span> at the shoreline significantly, causing a decrease of approximately 4 degrees C from the maximum temperature value and an increase of approximately 30% in peak PM10 <span class="hlt">levels</span>. Additionally, several stress indices were calculated in order to assess heat comfort conditions at the two sites. It was found that nocturnal comfort <span class="hlt">levels</span> are determined mainly by the urban heat island effect, the intensity of which reaches up to 8 degrees C, while the applied indices do not demonstrate any significant daytime thermal stress relief due to <span class="hlt">sea</span> breeze development.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.G21B0820F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.G21B0820F"><span>Mass-induced [|#8#|]<span class="hlt">Sea</span> <span class="hlt">Level</span> Variations in the Red <span class="hlt">Sea</span> from Satellite Altimetry and GRACE</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Feng, W.; Lemoine, J.; Zhong, M.; Hsu, H.</p> <p>2011-12-01</p> <p>We have analyzed mass-induced <span class="hlt">sea</span> <span class="hlt">level</span> variations (SLVs) in the Red <span class="hlt">Sea</span> from steric-corrected altimetry and GRACE between January 2003 and December 2010. The steric component of SLVs in the Red <span class="hlt">Sea</span> calculated from climatological temperature and salinity data is relatively small and anti-phase with the mass-induced SLV. The total SLV in the Red <span class="hlt">Sea</span> is mainly driven by the mass-induced SLV, which increases in winter when the Red <span class="hlt">Sea</span> gains the water mass from the Gulf of Aden and vice versa in summer. Spatial and temporal patterns of mass-induced SLVs in the Red <span class="hlt">Sea</span> from steric-corrected altimetry agree very well with GRACE observations. Both of two independent observations show high annual amplitude in the central Red <span class="hlt">Sea</span> (>20cm). Total mass-induced SLVs in the Red <span class="hlt">Sea</span> from two independent observations have similar annual amplitude and phase. One main purpose of our work is to see whether GRGS's ten-day GRACE results can observe intra-seasonal mass change in the Red <span class="hlt">Sea</span>. The wavelet coherence analysis indicates that GRGS's results show the high correlation with the steric-corrected SLVs on intra-seasonal time scale. The agreement is excellent for all the time-span until 1/3 year period and is patchy between 1/3 and 1/16 year period. Furthermore, water flux estimates from current-meter arrays and moorings show mass gain in winter and mass loss in summer, which is also consistent with altimetry and GRACE.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.5134U','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.5134U"><span>Steric <span class="hlt">sea</span> <span class="hlt">level</span> change in the Bay of Bengal: investigating the most variable component of <span class="hlt">sea</span> <span class="hlt">level</span> change</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Uebbing, Bernd; Kusche, Jürgen; Rietbroek, Roelof; Shum, Ck</p> <p>2015-04-01</p> <p>Regional <span class="hlt">sea</span> <span class="hlt">level</span> change is influenced by contributions from mass sources, like melting of glaciers and the ice-sheets in Greenland and Antarctica, as well as steric contributions from changes in temperature and salinity of the oceans. Radar altimetry indicates a <span class="hlt">sea</span> <span class="hlt">level</span> trend in the Bay of Bengal of about 6 mm- yr over the time period of 2002-2014, which is significantly larger than the global mean trend. Here, we explain 80% of this rise by steric contributions and 20% by mass-related contributions. The increased rise of <span class="hlt">sea</span> <span class="hlt">level</span> in the Bay of Bengal threatens the coastal vulnerability of the surrounding countries like Bangladesh, where this effect is exacerbated in combination with land subsidence of the very low lying coastal areas. The BanD-AID (Bangladesh Delta: Assessment of the Causes of <span class="hlt">Sea-level</span> Rise Hazards and Integrated Development of Predictive Modeling Towards Mitigation and Adaptation) project tries to assess the current and future <span class="hlt">sea</span> <span class="hlt">level</span> rise and its impacts on the people living in the threatened coastal areas. As a part of this, it is necessary to analyze the different mass and steric contributors to the total <span class="hlt">sea</span> <span class="hlt">level</span> rise to aid in the prediction of future risks. We use data from radar altimetry and the GRACE mission to separate the total <span class="hlt">sea</span> <span class="hlt">level</span> rise into contributions from mass sources and steric changes. In our approach, temporal GRACE gravity data and Jason-1 and -2 along track altimetry data are fitted to time invariant spatial patterns (fingerprints) to avoid problems with GRACE resolution, filtering, geocenter and related issues. Our results show that in the Bay of Bengal the steric component is influenced by annual and interannual phenomena and, at the same time, it is significantly larger compared to the individual mass contributions, which show a linear and relatively stable behavior over time. We validate the steric component of our inversion by comparing it to independent steric estimates from 4-D gridded temperature and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1813414T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1813414T"><span>Response of Arctic <span class="hlt">sea</span> <span class="hlt">level</span> and hydrography to hydrological regime change over boreal catchments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tourian, Mohammad J.; Sneeuw, Nico; Losch, Martin; Rabe, Benjamin</p> <p>2016-04-01</p> <p>Changes in freshwater influx into the Arctic Ocean are a key driver of regional dynamics and <span class="hlt">sea</span> <span class="hlt">level</span> change in the Arctic waters. Low-salinity surface waters maintain a strong stratification in the Arctic. This halocline largely shields the cool polar surface water and <span class="hlt">sea</span> ice from the warmer waters of Atlantic origin below and, hence, inhibits vertical heat fluxes of heat, salt and nutrients. Recently observed changes in the freshwater content of the upper Arctic Ocean raise the question of the effect of these changes on the region. Changes in the freshwater budget <span class="hlt">affect</span> regional steric <span class="hlt">sea</span> <span class="hlt">level</span>, but also the modified ocean dynamics may change <span class="hlt">sea</span> <span class="hlt">level</span> through mass transports within the Arctic. One component of the freshwater budget is continental runoff. The hydrological regime of river runoff appears to be non-stationary. There is both interannual variability and a significantly positive trend since the 1970s. The decreasing Arctic <span class="hlt">sea</span>-ice cover may be a possible reason for the non-stationary behavior of runoff, especially in coastal and marginal <span class="hlt">seas</span>. The decrease of <span class="hlt">sea</span> ice due to global warming would lead to cloud formation and, indeed, increased precipitation. During the warmer season, increased precipitation would lead to more discharge of freshwater to the Arctic shelves and basins. The observational record of discharge into the Arctic Ocean, however, is still too sparse to address important science questions about the long-term behavior and development of Arctic <span class="hlt">sea</span> <span class="hlt">level</span> and climate. Given the insufficient monitoring from in situ gauge networks, and without any outlook of improvement, spaceborne approaches are currently being investigated. In this contribution we assess the long-term behavior of monthly runoff time series obtained from hydro-geodetic approaches and explore the effects of interannual runoff variability and long term trends on ocean model simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.G51A0146M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.G51A0146M"><span>Monitoring <span class="hlt">Sea</span> <span class="hlt">Level</span> At L'Estartit, Spain</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Martinez-Benjamin, J.; Ortiz Castellon, M.; Martinez-Garcia, M.; Talaya, J.; Rodriguez Velasco, G.; Perez, B.</p> <p>2007-12-01</p> <p><span class="hlt">Sea</span> <span class="hlt">level</span> is an environmental variable which is widely recognised as being important in many scientific disciplines as a control parameter for coastal dynamical processes or climate processes in the coupled atmosphere-ocean systems, as well as engineering applications. A major source of <span class="hlt">sea-level</span> data are the national networks of coastal tide gauges, in Spain belonging to different institutions as the Instituto Geográfico Nacional (IGN), Puertos del Estado (PE), Instituto Hidrográfico de la Marina (IHM), Ports de la Generalitat, etc. Three Begur Cape experiences on radar altimeter calibration and marine geoid mapping made on 1999, 2000 and 2002 are overviewed. The marine geoid has been used to relate the coastal tide gauge data from l'Estartit harbour to off-shore altimetric data. The necessity to validate and calibrate the satellite's altimeter due to increasing needs in accuracy and long term integrity implies establishing calibration sites with enhanced ground based methods for <span class="hlt">sea</span> <span class="hlt">level</span> monitoring. A technical Spanish contribution to the calibration experience has been the design of GPS buoys and GPS catamaran taking in account the University of Colorado at Boulder and Senetosa/Capraia designs. Altimeter calibration is essential to obtain an absolute measure of <span class="hlt">sea</span> <span class="hlt">level</span>, as are knowing the instrument's drifts and bias. Specially designed tidegauges are necessary to improve the quality of altimetric data, preferably near the satellite track. Further, due to systematic differences a month instruments onboard different satellites, several in-situ calibrations are essentials to tie their systematic differences. L'Estartit tide gauge is a classical floating tide gauge set up in l'Estartit harbour (NE Spain) in 1990. It provides good quality information about the changes in the <span class="hlt">sea</span> heights at centimetre <span class="hlt">level</span>, that is the magnitude of the common tides in theMediterranean. In the framework of a Spanish Space Project, ref:ESP2001- 4534-PE, the instrumentation of <span class="hlt">sea</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..1413767Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..1413767Y"><span>Preparing Coastal Parks for Future <span class="hlt">Sea</span> <span class="hlt">Level</span> Rise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Young, R.; Peek, K.</p> <p>2012-04-01</p> <p>The United States National Park Service (NPS) manages significant stretches of shoreline along the U.S. Atlantic, Pacific, and Gulf Coasts that are vulnerable to long-term <span class="hlt">sea</span> <span class="hlt">level</span> rise, shoreline erosion, and storm impacts. These parks have a wide variety of missions— protecting some of the nation's most important natural and cultural resources. The parks must also provide visitor access and education requiring infrastructure such as roads, visitor centers, trails, and buildings for facilities management. Planning for the likely impacts from <span class="hlt">sea</span> <span class="hlt">level</span> rise to both resources and infrastructure is a complex balancing act. Using coastal engineering to protect cultural resources or infrastructure may harm natural resources. At the same time, there are clearly some cultural and historical resources that are so critical that they must be protected. In an attempt to begin to attack this dilemma, the NPS Climate Change Response Program has initiated a <span class="hlt">sea</span> <span class="hlt">level</span> rise adaptation study that will provide a first-order tally of the park assets at risk to <span class="hlt">sea</span> <span class="hlt">level</span> rise and to begin to develop a plan for prioritizing those assets that must be protected, those that can be moved or abandoned, and an examination of how best to approach this without harming critical natural resources. This presentation will discuss the preliminary results of this effort along with several relevant case studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5112891','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5112891"><span>Fluctuating Mesozoic and Cenozoic <span class="hlt">sea</span> <span class="hlt">levels</span> and implications for stratigraphy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Haq, B.U. )</p> <p>1988-12-01</p> <p>Sequence stratigraphy encompasses depositional models of genetically related packages of sediments deposited during various phases of cycle of <span class="hlt">sea</span> <span class="hlt">level</span> change, i.e., from a lowstand to highstand to the subsequent lowstand. The application of these models to marine outcrops around the world and to subsurface data led to the construction of Mesozoic-Cenozoic <span class="hlt">sea</span> <span class="hlt">level</span> curves with greater event resolution than the earlier curves based on seismic data alone. Construction of these better resolution curves begins with an outline of the principles of sequence-stratigraphic analysis and the reconstruction of the history of <span class="hlt">sea</span> <span class="hlt">level</span> change from outcrop and subsurface data for the past 250 Ma. Examples of marine sections from North America, Europe, and Asia can be used to illustrate sequence analysis of outcrop data and the integration of chronostratigraphy with <span class="hlt">sea</span> <span class="hlt">level</span> history. Also important are the implications of sequence-stratigraphic methodology and the new cycle charts to various disciplines of stratigraphy, environmental reconstruction, and basin analysis. The relationship of unconformities along the continental margins to hiatuses and dissolution surfaces in the deep basins must also be explored, as well as the relevance of sequence-stratigraphic methodology to biofacies and source rock prediction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010OcDyn..60..883M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010OcDyn..60..883M"><span>Variability in Solomon <span class="hlt">Sea</span> circulation derived from altimeter <span class="hlt">sea</span> <span class="hlt">level</span> data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Melet, Angélique; Gourdeau, Lionel; Verron, Jacques</p> <p>2010-08-01</p> <p>The Solomon <span class="hlt">Sea</span> is a key region in the Pacific Ocean where equatorial and subtropical circulations are connected. The region exhibits the highest <span class="hlt">levels</span> in <span class="hlt">sea</span> <span class="hlt">level</span> variability in the entire south tropical Pacific Ocean. Altimeter data was utilized to explore <span class="hlt">sea</span> <span class="hlt">level</span> and western boundary currents in this poorly understood portion of the ocean. Since the geography of the region is extremely intricate, with numerous islands and complex bathymetry, specifically reprocessed along-track data in addition to standard gridded data were utilized in this study. <span class="hlt">Sea</span> <span class="hlt">level</span> anomalies (SLA) in the Solomon <span class="hlt">Sea</span> principally evolve at seasonal and interannual time scales. The annual cycle is phased by Rossby waves arriving in the Solomon Strait, whereas the interannual signature corresponds to the basin-scale ENSO mode. The highest SLA variability are concentrated in the eastern Solomon <span class="hlt">Sea</span>, particularly at the mouth of the Solomon Strait, where they are associated with a high eddy kinetic energy signal that was particularly active during the phase transition during the 1997-1998 ENSO event. Track data appear especially helpful for documenting the fine structure of surface coastal currents. The annual variability of the boundary currents that emerged from altimetry compared quite well with the variability seen at the thermocline <span class="hlt">level</span>, as based on numerical simulations. At interannual time scales, western boundary current transport anomalies counterbalance changes in western equatorial Pacific warm water volume, confirming the phasing of South Pacific western boundary currents to ENSO. Altimetry appears to be a valuable source of information for variability in low latitude western boundary currents and their associated transport in the South Pacific.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1812016S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1812016S"><span>Uncertainty estimates of altimetric Global Mean <span class="hlt">Sea</span> <span class="hlt">Level</span> timeseries</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Scharffenberg, Martin; Hemming, Michael; Stammer, Detlef</p> <p>2016-04-01</p> <p>An attempt is being presented concerned with providing uncertainty measures for global mean <span class="hlt">sea</span> <span class="hlt">level</span> time series. For this purpose <span class="hlt">sea</span> surface height (SSH) fields, simulated by the high resolution STORM/NCEP model for the period 1993 - 2010, were subsampled along altimeter tracks and processed similar to techniques used by five working groups to estimate GMSL. Results suggest that the spatial and temporal resolution have a substantial impact on GMSL estimates. Major impacts can especially result from the interpolation technique or the treatment of SSH outliers and easily lead to artificial temporal variability in the resulting time series.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.G31A0911V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.G31A0911V"><span><span class="hlt">Sea</span> <span class="hlt">Level</span> Variation at the North Atlantic Ocean from Altimetry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vigo, I.; Sanchez-Reales, J. M.; Belda, S.</p> <p>2012-12-01</p> <p>About twenty years of multi-satellite radar altimeter data are analyzed to investigate the <span class="hlt">sea-level</span> variation (SLV) of the North Atlantic Ocean. In particular seasonal variations and inter-seasonal trends are studied. <span class="hlt">Sea</span> surface temperature and ice mass lost variations at Greenland are investigated as potential contributors of SLV in the case. It was found a quadratic acceleration term to be significant at some areas mainly located at the sub-polar gyre region. Results are consistent with changes in temperature data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6577148','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6577148"><span><span class="hlt">Sea</span> <span class="hlt">level</span> during the Phanerozoic - what causes the fluctuations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Harrison, C.G.A.</p> <p>1985-01-01</p> <p>All possible causes of <span class="hlt">sea</span> <span class="hlt">level</span> change have been analyzed in order to explain the fall of <span class="hlt">sea</span> <span class="hlt">level</span> since the Cretaceous. The most important effect is the decrease in volume of the ridge crests due to an overall decrease in the rate of spreading since the Cretaceous. Other factors in order of decreasing importance are the reduction of the thermal bulge which accompanied the episode of Pacific volcanism between 110 and 70 my bp, the production of continental ice, the effect of the collision of India with Asia, and cooling of the ocean water. Sedimentation variation in the deep ocean has the effect of raising <span class="hlt">sea</span> <span class="hlt">level</span> a modest amount. The net variation in <span class="hlt">sea</span> <span class="hlt">level</span> during the past 80 million years has been a reduction by about 280 m after having allowed for isostatic adjustment of the ocean floor. This is considerably larger, than <span class="hlt">sea</span> <span class="hlt">level</span> calculated from the amount of continental flooding, and it is proposed that the discrepancy is due to a change in the continental hypsographic curve following the breakup of Pangea. This hypothesis is born out by studies of flooding during the Phanerozoic which reveal that flooding was very low at the beginning of the Mesozoic during a time of continental agglomeration, and high during much of the Paleozoic, which was a time of continental separation. In the Cambrian there is evidence for an increase in flooding with time, and at the beginning of the Cambrian flooding was not much greater than at the beginning of the Mesozoic, suggesting that it marked a time just subsequent to the break up of a super continent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70024231','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70024231"><span>Responses of coastal wetlands to rising <span class="hlt">sea</span> <span class="hlt">level</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Morris, J.T.; Sundareshwar, P.V.; Nietch, C.T.; Kjerfve, B.; Cahoon, D.R.</p> <p>2002-01-01</p> <p>Salt marsh ecosystems are maintained by the dominant macrophytes that regulate the elevation of their habitat within a narrow portion of the intertidal zone by accumulating organic matter and trapping inorganic sediment. The long-term stability of these ecosystems is explained by interactions among <span class="hlt">sea</span> <span class="hlt">level</span>, land elevation, primary production, and sediment accretion that regulate the elevation of the sediment surface toward an equilibrium with mean <span class="hlt">sea</span> <span class="hlt">level</span>. We show here in a salt marsh that this equilibrium is adjusted upward by increased production of the salt marsh macrophyte Spartina alterniflora and downward by an increasing rate of relative <span class="hlt">sea-level</span> rise (RSLR). Adjustments in marsh surface elevation are slow in comparison to interannual anomalies and long-period cycles of <span class="hlt">sea</span> <span class="hlt">level</span>, and this lag in sediment elevation results in significant variation in annual primary productivity. We describe a theoretical model that predicts that the system will be stable against changes in relative mean <span class="hlt">sea</span> <span class="hlt">level</span> when surface elevation is greater than what is optimal for primary production. When surface elevation is less than optimal, the system will be unstable. The model predicts that there is an optimal rate of RSLR at which the equilibrium elevation and depth of tidal flooding will be optimal for plant growth. However, the optimal rate of RSLR also represents an upper limit because at higher rates of RSLR the plant community cannot sustain an elevation that is within its range of tolerance. For estuaries with high sediment loading, such as those on the southeast coast of the United States, the limiting rate of RSLR was predicted to be at most 1.2 cm/yr, which is 3.5 times greater than the current, long-term rate of RSLR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.U22A..03C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.U22A..03C"><span>Understanding and projecting <span class="hlt">sea</span> <span class="hlt">level</span> change: improvements and uncertainties (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Church, J. A.; Clark, P. U.; Cazenave, A. A.; Gregory, J. M.; Jevrejeva, S.; Merrifield, M. A.; Milne, G. A.; Nerem, R.; Payne, A. J.; Pfeffer, W. T.; Stammer, D.; Levermann, A.; Nunn, P.; Unnikrishnan, A. S.</p> <p>2013-12-01</p> <p>The rate of global mean <span class="hlt">sea</span> <span class="hlt">level</span> rise (GMSLR) has accelerated during the last two centuries, from a rate of order tenths of mm yr-1 during the late Holocene, to about 1.7 mm yr-1 since 1901. Ocean thermal expansion and glacier melting were the dominant contributors to 20th century GMSLR, with relatively small contributions from the Greenland and Antarctic ice sheets. Process-based models suggest that the larger rate of rise since 1990 results from increased radiative forcing (both natural and anthropogenic) and increased ice-sheet outflow, induced by warming of the immediately adjacent ocean. Confidence in projections of global mean <span class="hlt">sea</span> <span class="hlt">level</span> rise has increased since the AR4 because of improved physical process-based understanding of observed <span class="hlt">sea</span> <span class="hlt">level</span> change, especially in recent decades, and the inclusion of future rapid ice-sheet dynamical changes, for which a quantitative assessment could not be made on the basis of scientific knowledge available at the time of the AR4. By 2100, the rate of GMSLR for a scenario of high emissions (RCP8.5) could approach the average rates that occurred during the last deglaciation, whereas for a strong emissions mitigation scenario (RCP2.6) it could stabilise at rates similar to those of the early 21st century. In either case, GMSLR will continue for many subsequent centuries. Although there has been much recent progress, projections of ice-sheet change are still uncertain, especially beyond 2100. Future <span class="hlt">sea</span> <span class="hlt">level</span> change will not be globally uniform, but models still exhibit substantial disagreement in projections of ice mass loss and ocean dynamics, which are the main influences on the pattern. Uncertainty in projections of future storminess is a further obstacle to confident projection of changes in <span class="hlt">sea</span> <span class="hlt">level</span> extremes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMOS33C1084P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMOS33C1084P"><span>Pacific <span class="hlt">Sea</span> <span class="hlt">Level</span> Rise Pattern and Global Warming Hiatus</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Peyser, C.; Yin, J.; Landerer, F. W.</p> <p>2014-12-01</p> <p>Two important topics in current climate research are the global warming hiatus and the seesaw pattern of <span class="hlt">sea</span> <span class="hlt">level</span> rise (SLR) in the Pacific Ocean. We use ocean temperature and <span class="hlt">sea-level</span> observations along with CMIP5 climate modelling data to investigate the relationship between the warming hiatus and <span class="hlt">sea-level</span> variability in the Pacific Ocean. We analyse ocean heat content (OHC) trend by basin and layer for the full record (1945-2012) as well as the hiatus period (1998-2012). The result confirms the importance of the Pacific for heat uptake during the hiatus. Notably, the subsurface layer of the Pacific shows significant increase in OHC during the hiatus and a strong east-west compensation. This is mainly responsible for and reflected by the seesaw pattern of the Pacific <span class="hlt">sea</span> <span class="hlt">level</span> through thermosteric effect. The control simulations from 38 CMIP5 models indicate that the seesaw pattern of SLR in the Pacific is mainly a feature of decadal to multidecadal variability. Most CMIP5 models can capture this variability, especially in the Pacific Decadal Oscillation region (poleward of 20°N). The CMIP5 control runs show that during periods of negative trends of global temperatures (analogous to hiatus decades in a warming world), <span class="hlt">sea</span> <span class="hlt">level</span> increases in the western Pacific and decreases in the eastern Pacific. The opposite is true during periods of positive temperature trend (accelerated warming). These results suggest that a possible flip of the Pacific SLR seesaw would imply a resumption of surface warming and a SLR acceleration along the U.S. West Coast.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMPP33C1251V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMPP33C1251V"><span>Evidence from the Seychelles of Last Interglacial <span class="hlt">Sea</span> <span class="hlt">Level</span> Oscillations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vyverberg, K.; Dutton, A.; Dechnik, B.; Webster, J.; Zwartz, D.</p> <p>2014-12-01</p> <p>Several studies indicate that <span class="hlt">sea</span> <span class="hlt">level</span> oscillated during Marine Isotope Stage (MIS) 5e, but the details of these scenarios, including the number of <span class="hlt">sea</span> <span class="hlt">level</span> oscillations, are still debated. We lack a detailed understanding of the sensitivity of the large polar ice sheets to changes in temperature that could result in eustatic <span class="hlt">sea</span> <span class="hlt">level</span> oscillations. Because the Seychelles are located far from the margins of the Last Glacial Maximum northern hemisphere ice sheets, they have not been subjected to glacial isostatic adjustment, and have been tectonically stable since the Last Interglacial period; therefore, they provide a robust record of eustatic <span class="hlt">sea</span> <span class="hlt">level</span> during MIS 5e. All of the outcrops we examined contain unconformities and/or sharp transitions between facies, though the nature of these boundaries varies between sites. In some outcrops we observed a hardground comprising fine-grained, mollusc-rich sediment layer between distinct generations of in situ coralgal framework. In one outcrop, this succession was observed twice, where two generations of reef growth were each capped by a strongly indurated fine-grained, mollusc-rich sediment layer. At the site with the greatest vertical extent of outcrop, there is a marked difference in the taxonomic composition of the coral community above and below an unconformable surface, but the indurated fine-grained, sediment layer observed elsewhere was absent. Most of the other outcrops we studied contained a common succession of facies from in situ reef units overlain by cemented coral rubble. In two dated outcrops, the age of corals above and below the rubble layer are the same age. The hardgrounds and rubble layers may represent ephemeral exposure of the reef units during two drops in <span class="hlt">sea</span> <span class="hlt">level</span>. The inference of multiple meter-scale oscillations during the MIS 5e highstand indicates a more dynamic cryosphere than the present interglacial, although the climatic threshold for more volatile polar ice sheets is not yet clear.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26062511','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26062511"><span>Bipolar seesaw control on last interglacial <span class="hlt">sea</span> <span class="hlt">level</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Marino, G; Rohling, E J; Rodríguez-Sanz, L; Grant, K M; Heslop, D; Roberts, A P; Stanford, J D; Yu, J</p> <p>2015-06-11</p> <p>Our current understanding of ocean-atmosphere-cryosphere interactions at ice-age terminations relies largely on assessments of the most recent (last) glacial-interglacial transition, Termination I (T-I). But the extent to which T-I is representative of previous terminations remains unclear. Testing the consistency of termination processes requires comparison of time series of critical climate parameters with detailed absolute and relative age control. However, such age control has been lacking for even the penultimate glacial termination (T-II), which culminated in a <span class="hlt">sea-level</span> highstand during the last interglacial period that was several metres above present. Here we show that Heinrich Stadial 11 (HS11), a prominent North Atlantic cold episode, occurred between 135 ± 1 and 130 ± 2 thousand years ago and was linked with rapid <span class="hlt">sea-level</span> rise during T-II. Our conclusions are based on new and existing data for T-II and the last interglacial that we collate onto a single, radiometrically constrained chronology. The HS11 cold episode punctuated T-II and coincided directly with a major deglacial meltwater pulse, which predominantly entered the North Atlantic Ocean and accounted for about 70 per cent of the glacial-interglacial <span class="hlt">sea-level</span> rise. We conclude that, possibly in response to stronger insolation and CO2 forcing earlier in T-II, the relationship between climate and ice-volume changes differed fundamentally from that of T-I. In T-I, the major <span class="hlt">sea-level</span> rise clearly post-dates Heinrich Stadial 1. We also find that HS11 coincided with sustained Antarctic warming, probably through a bipolar seesaw temperature response, and propose that this heat gain at high southern latitudes promoted Antarctic ice-sheet melting that fuelled the last interglacial <span class="hlt">sea-level</span> peak.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008GeCar..34..109J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008GeCar..34..109J"><span>Geoid Profiles in the Baltic <span class="hlt">Sea</span> Determined Using GPS and <span class="hlt">Sea</span> <span class="hlt">Level</span> Surface</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jürgenson, Harli; Liibusk, Aive; Ellmann, Artu</p> <p>2008-12-01</p> <p>The idea was to compare the geoid of <span class="hlt">sea</span> areas by an independent method, like GPS <span class="hlt">levelling</span>, on the mainland. On the earth surface we can compare the gravimetric geoid with GPS <span class="hlt">levelling</span> to get an accuracy estimation and tilt information. On the <span class="hlt">sea</span> we can do it by the GPS methodology and eliminating the current water tilt corrections and the <span class="hlt">sea</span> surface topography effect. A modern GPS device on board a ferry can store data every second and determine heights with an accuracy of a few centimetres (using the kinematic method with the postprocessing of data obtained from several base stations close to the ferry line). As a result, it is possible to observe the current water <span class="hlt">level</span>'s relative profile in reference to the ellipsoid. Some areas close to Estonia, such as the eastern part of the Gulf of Finland, are not completely covered by gravity measurements. The Baltic <span class="hlt">Sea</span> has been measured using airborne gravimetry with the accuracy of about 2 mGal. Therefore, the gravimetric geoid is not fully reliable for the region either. If we take into account the tilt of the water <span class="hlt">level</span> at the moment of measurement, we can observe the relative change of the geoid using an independent methodology, which serves as a comparison to the gravimetric geoid solution. The main problem during the measurement campaign, of course, was how to eliminate a water tilt. Water placement in relation to <span class="hlt">level</span> surface is a very complex issue; special studies of that were conducted as well.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26020776','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26020776"><span>Metatranscriptomic Analysis of Pycnopodia helianthoides (Asteroidea) <span class="hlt">Affected</span> by <span class="hlt">Sea</span> Star Wasting Disease.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gudenkauf, Brent M; Hewson, Ian</p> <p>2015-01-01</p> <p><span class="hlt">Sea</span> star wasting disease (SSWD) describes a suite of symptoms reported in asteroids of the North American Pacific Coast. We performed a metatranscriptomic survey of asymptomatic and symptomatic sunflower star (Pycnopodia helianthoides) body wall tissues to understand holobiont gene expression in tissues <span class="hlt">affected</span> by SSWD. Metatranscriptomes were highly variable between replicate libraries, and most differentially expressed genes represented either transcripts of associated microorganisms (particularly Pseudomonas and Vibrio relatives) or low-<span class="hlt">level</span> echinoderm transcripts of unknown function. However, the pattern of annotated host functional genes reflects enhanced apoptotic and tissue degradation processes and decreased energy metabolism, while signalling of death-related proteins was greater in asymptomatic and symptomatic tissues. Our results suggest that the body wall tissues of SSWD-<span class="hlt">affected</span> asteroids may undergo structural changes during disease progression, and that they are stimulated to undergo autocatalytic cell death processes.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4447261','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4447261"><span>Metatranscriptomic Analysis of Pycnopodia helianthoides (Asteroidea) <span class="hlt">Affected</span> by <span class="hlt">Sea</span> Star Wasting Disease</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Gudenkauf, Brent M.; Hewson, Ian</p> <p>2015-01-01</p> <p><span class="hlt">Sea</span> star wasting disease (SSWD) describes a suite of symptoms reported in asteroids of the North American Pacific Coast. We performed a metatranscriptomic survey of asymptomatic and symptomatic sunflower star (Pycnopodia helianthoides) body wall tissues to understand holobiont gene expression in tissues <span class="hlt">affected</span> by SSWD. Metatranscriptomes were highly variable between replicate libraries, and most differentially expressed genes represented either transcripts of associated microorganisms (particularly Pseudomonas and Vibrio relatives) or low-<span class="hlt">level</span> echinoderm transcripts of unknown function. However, the pattern of annotated host functional genes reflects enhanced apoptotic and tissue degradation processes and decreased energy metabolism, while signalling of death-related proteins was greater in asymptomatic and symptomatic tissues. Our results suggest that the body wall tissues of SSWD-<span class="hlt">affected</span> asteroids may undergo structural changes during disease progression, and that they are stimulated to undergo autocatalytic cell death processes. PMID:26020776</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ClDy..tmp..367M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ClDy..tmp..367M"><span>Impact of accelerated future global mean <span class="hlt">sea</span> <span class="hlt">level</span> rise on hypoxia in the Baltic <span class="hlt">Sea</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meier, H. E. M.; Höglund, A.; Eilola, K.; Almroth-Rosell, E.</p> <p>2016-08-01</p> <p>Expanding hypoxia is today a major threat for many coastal <span class="hlt">seas</span> around the world and disentangling its drivers is a large challenge for interdisciplinary research. Using a coupled physical-biogeochemical model we estimate the impact of past and accelerated future global mean <span class="hlt">sea</span> <span class="hlt">level</span> rise (GSLR) upon water exchange and oxygen conditions in a semi-enclosed, shallow <span class="hlt">sea</span>. As a study site, the Baltic <span class="hlt">Sea</span> was chosen that suffers today from eutrophication and from dead bottom zones due to (1) excessive nutrient loads from land, (2) limited water exchange with the world ocean and (3) perhaps other drivers like global warming. We show from model simulations for the period 1850-2008 that the impacts of past GSLR on the marine ecosystem were relatively small. If we assume for the end of the twenty-first century a GSLR of +0.5 m relative to today's mean <span class="hlt">sea</span> <span class="hlt">level</span>, the impact on the marine ecosystem may still be small. Such a GSLR corresponds approximately to the projected ensemble-mean value reported by the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. However, we conclude that GSLR should be considered in future high-end projections (>+1 m) for the Baltic <span class="hlt">Sea</span> and other coastal <span class="hlt">seas</span> with similar hydrographical conditions as in the Baltic because GSLR may lead to reinforced saltwater inflows causing higher salinity and increased vertical stratification compared to present-day conditions. Contrary to intuition, reinforced ventilation of the deep water does not lead to overall improved oxygen conditions but causes instead expanded dead bottom areas accompanied with increased internal phosphorus loads from the sediments and increased risk for cyanobacteria blooms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24739960','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24739960"><span><span class="hlt">Sea-level</span> and deep-<span class="hlt">sea</span>-temperature variability over the past 5.3 million years.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rohling, E J; Foster, G L; Grant, K M; Marino, G; Roberts, A P; Tamisiea, M E; Williams, F</p> <p>2014-04-24</p> <p>Ice volume (and hence <span class="hlt">sea</span> <span class="hlt">level</span>) and deep-<span class="hlt">sea</span> temperature are key measures of global climate change. <span class="hlt">Sea</span> <span class="hlt">level</span> has been documented using several independent methods over the past 0.5 million years (Myr). Older periods, however, lack such independent validation; all existing records are related to deep-<span class="hlt">sea</span> oxygen isotope (δ(18)O) data that are influenced by processes unrelated to <span class="hlt">sea</span> <span class="hlt">level</span>. For deep-<span class="hlt">sea</span> temperature, only one continuous high-resolution (Mg/Ca-based) record exists, with related <span class="hlt">sea-level</span> estimates, spanning the past 1.5 Myr. Here we present a novel <span class="hlt">sea-level</span> reconstruction, with associated estimates of deep-<span class="hlt">sea</span> temperature, which independently validates the previous 0-1.5 Myr reconstruction and extends it back to 5.3 Myr ago. We find that deep-<span class="hlt">sea</span> temperature and <span class="hlt">sea</span> <span class="hlt">level</span> generally decreased through time, but distinctly out of synchrony, which is remarkable given the importance of ice-albedo feedbacks on the radiative forcing of climate. In particular, we observe a large temporal offset during the onset of Plio-Pleistocene ice ages, between a marked cooling step at 2.73 Myr ago and the first major glaciation at 2.15 Myr ago. Last, we tentatively infer that ice sheets may have grown largest during glacials with more modest reductions in deep-<span class="hlt">sea</span> temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012CSR....33...14E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012CSR....33...14E"><span><span class="hlt">Sea</span> <span class="hlt">level</span> variability influencing coastal flooding in the Swan River region, Western Australia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Eliot, Matt</p> <p>2012-02-01</p> <p>Coastal flooding refers to the incidence of high water <span class="hlt">levels</span> produced by water <span class="hlt">level</span> fluctuations of marine origin, rather than riverine floods. An understanding of the amplitude and frequency of high water <span class="hlt">level</span> events is essential to foreshore management and the design of many coastal and estuarine facilities. Coastal flooding events generally determine public perception of <span class="hlt">sea</span> <span class="hlt">level</span> phenomena, as they are commonly associated with erosion events. This investigation has explored the nature of coastal flooding events <span class="hlt">affecting</span> the Swan River Region, Western Australia, considering water <span class="hlt">level</span> records at four sites in the estuary and lower river, extending from the mouth of the Swan River to 40 km upstream. The analysis examined the significance of tides, storms and mean <span class="hlt">sea</span> <span class="hlt">level</span> fluctuations over both seasonal and inter-annual time scales. The relative timing of these processes is significant for the enhanced or reduced frequency of coastal flooding. These variations overlie net <span class="hlt">sea</span> <span class="hlt">level</span> rise previously reported from the coastal Fremantle record, which is further supported by changes to the distribution of high water <span class="hlt">level</span> events at an estuarine tidal station. Seasonally, coastal flooding events observed in the Swan River region are largely restricted to the period from May to July due to the relative phases of the annual mean <span class="hlt">sea</span> fluctuation and biannual tidal cycle. Although significant storm surge events occur outside this period, their impact is normally reduced, as they are superimposed on lower tidal and mean <span class="hlt">sea</span> <span class="hlt">level</span> conditions. Over inter-annual time scales tide, storminess and mean <span class="hlt">sea</span> <span class="hlt">level</span> produce cycles of enhanced and depressed frequency of coastal flooding. For the Swan River region, the inter-annual tidal variation is regular, dominated by the 18.6 year lunar nodal cycle. Storminess and mean <span class="hlt">sea</span> <span class="hlt">level</span> variations are independent and irregular, with cycles from 3 to 10 year duration. Since 1960, these fluctuations have not occurred in phase</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7423M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7423M"><span>Geodetic infrastructure at the Barcelona harbour for <span class="hlt">sea</span> <span class="hlt">level</span> monitoring</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Martinez-Benjamin, Juan Jose; Gili, Josep; Lopez, Rogelio; Tapia, Ana; Pros, Francesc; Palau, Vicenc; Perez, Begona</p> <p>2015-04-01</p> <p>The presentation is directed to the description of the actual geodetic infrastructure of Barcelona harbour with three tide gauges of different technologies for <span class="hlt">sea</span> <span class="hlt">level</span> determination and contribution to regional <span class="hlt">sea</span> <span class="hlt">level</span> rise and understanding past and present <span class="hlt">sea</span> <span class="hlt">level</span> rise in the Barcelona harbour. It is intended that the overall system will constitute a CGPS Station of the ESEAS (European <span class="hlt">Sea</span> <span class="hlt">Level</span>) and TIGA (GPS Tide Gauge Benchmark Monitoring) networks. At Barcelona harbour there is a MIROS radar tide gauge belonging to Puertos del Estado (Spanish Harbours).The radar sensor is over the water surface, on a L-shaped structure which elevates it a few meters above the quay shelf. 1-min data are transmitted to the ENAGAS Control Center by cable and then sent each 1 min to Puertos del Estado by e-mail. The information includes wave forescast (mean period, significant wave height, <span class="hlt">sea</span> <span class="hlt">level</span>, etc.This sensor also measures agitation and sends wave parameters each 20 min. There is a GPS station Leica Geosystems GRX1200 GG Pro and antenna AX 1202 GG. The Control Tower of the Port of Barcelona is situated in the North dike of the so-called Energy Pier in the Barcelona harbor (Spain). This tower has different kind of antennas for navigation monitoring and a GNSS permanent station. As the tower is founded in reclaimed land, and because its metallic structure, the 50 m building is subjected to diverse movements, including periodic fluctuations due to temperature changes. In this contribution the 2009, 2011, 2012, 2013 and 2014 the necessary monitoring campaigns are described. In the framework of a Spanish Space Project, the instrumentation of <span class="hlt">sea</span> <span class="hlt">level</span> measurements has been improved by providing the Barcelona site with a radar tide gauge Datamar 2000C from Geonica S.L. in June 2014 near an acoustic tide gauge from the Barcelona Harbour installed in 2013. Precision <span class="hlt">levelling</span> has been made several times in the last two years because the tower is founded in reclaimed land and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016QSRv..137...54B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016QSRv..137...54B"><span>Modelling <span class="hlt">sea</span> <span class="hlt">level</span> data from China and Malay-Thailand to estimate Holocene ice-volume equivalent <span class="hlt">sea</span> <span class="hlt">level</span> change</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bradley, Sarah L.; Milne, Glenn A.; Horton, Benjamin P.; Zong, Yongqiang</p> <p>2016-04-01</p> <p>This study presents a new model of Holocene ice-volume equivalent <span class="hlt">sea</span> <span class="hlt">level</span> (ESL), extending a previously published global ice sheet model (Bassett et al., 2005), which was unconstrained from 10 kyr BP to present. This new model was developed by comparing relative <span class="hlt">sea</span> <span class="hlt">level</span> (RSL) predictions from a glacial isostatic adjustment (GIA) model to a suite of Holocene <span class="hlt">sea</span> <span class="hlt">level</span> index points from China and Malay-Thailand. Three consistent data-model misfits were found using the Bassett et al. (2005) model: an over-prediction in the height of maximum <span class="hlt">sea</span> <span class="hlt">level</span>, the timing of this maximum, and the temporal variation of <span class="hlt">sea</span> <span class="hlt">level</span> from the time of the highstand to present. The data-model misfits were examined for a large suite of ESL scenarios and a range of earth model parameters to determine an optimum model of Holocene ESL. This model is characterised by a slowdown in melting at ∼7 kyr BP, associated with the final deglaciation of the Laurentide Ice Sheet, followed by a continued rise in ESL until ∼1 kyr BP of ∼5.8 m associated with melting from the Antarctic Ice Sheet. It was not possible to identify an earth viscosity model that provided good fits for both regions; with the China data preferring viscosity values in the upper mantle of less than 1.5 × 1020 Pa s and the Malay-Thailand data preferring greater values. We suggest that this inference of a very weak upper mantle for the China data originates from the nearby subduction zone and Hainan Plume. The low viscosity values may also account for the lack of a well-defined highstand at the China sites.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70170271','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70170271"><span>Late Holocene <span class="hlt">sea</span> <span class="hlt">level</span> variability and Atlantic Meridional Overturning Circulation</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Cronin, Thomas M.; Farmer, Jesse R.; Marzen, R. E.; Thomas, E.; Varekamp, J.C.</p> <p>2014-01-01</p> <p>Pre-twentieth century <span class="hlt">sea</span> <span class="hlt">level</span> (SL) variability remains poorly understood due to limits of tide gauge records, low temporal resolution of tidal marsh records, and regional anomalies caused by dynamic ocean processes, notably multidecadal changes in Atlantic Meridional Overturning Circulation (AMOC). We examined SL and AMOC variability along the eastern United States over the last 2000 years, using a SL curve constructed from proxy <span class="hlt">sea</span> surface temperature (SST) records from Chesapeake Bay, and twentieth century SL-<span class="hlt">sea</span> surface temperature (SST) relations derived from tide gauges and instrumental SST. The SL curve shows multidecadal-scale variability (20–30 years) during the Medieval Climate Anomaly (MCA) and Little Ice Age (LIA), as well as the twentieth century. During these SL oscillations, short-term rates ranged from 2 to 4 mm yr−1, roughly similar to those of the last few decades. These oscillations likely represent internal modes of climate variability related to AMOC variability and originating at high latitudes, although the exact mechanisms remain unclear. Results imply that dynamic ocean changes, in addition to thermosteric, glacio-eustatic, or glacio-isostatic processes are an inherent part of SL variability in coastal regions, even during millennial-scale climate oscillations such as the MCA and LIA and should be factored into efforts that use tide gauges and tidal marsh sediments to understand global <span class="hlt">sea</span> <span class="hlt">level</span> rise.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900033471&hterms=Barometers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DBarometers','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900033471&hterms=Barometers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DBarometers"><span>Seasonal variability in global <span class="hlt">sea</span> <span class="hlt">level</span> observed with Geosat altimetry</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zlotnicki, V.; Fu, L.-L.; Patzert, W.</p> <p>1989-01-01</p> <p>Time changes in global mesoscale <span class="hlt">sea</span> <span class="hlt">level</span> variances were observed with satellite altimetry between November 1986 and March 1988, showing significant, geographically coherent seasonal patterns. The NE Pacific and NE Atlantic variances show the most reliable patterns, higher than their yearly averages in both the fall and winter. The response to wind forcing appears as the major contributor to the NE Pacific and Atlantic signals; errors in the estimated inverse barometer response due to errors in atmospheric pressure, residual orbit errors, and errors in <span class="hlt">sea</span> state bias are evaluated and found to be negligible contributors to this particular signal. The equatorial regions also show significant seasonal patterns, but the uncertainties in the wet tropospheric correction prevent definitive conclusions. The western boundary current changes are very large but not statistically significant. Estimates of the regression coefficient between <span class="hlt">sea</span> <span class="hlt">level</span> and significant wave height, an estimate of the <span class="hlt">sea</span> state bias correction, range between 2.3 and 2.9 percent and vary with the type of orbit correction applied.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17763873','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17763873"><span>Predator diversity and density <span class="hlt">affect</span> <span class="hlt">levels</span> of predation upon strongly interactive species in temperate rocky reefs.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Guidetti, Paolo</p> <p>2007-12-01</p> <p>Indirect effects of predators in the classic trophic cascade theory involve the effects of basal species (e.g. primary producers) mediated by predation upon strongly interactive consumers (e.g. grazers). The diversity and density of predators, and the way in which they interact, determine whether and how the effects of different predators on prey combine. Intraguild predation, for instance, was observed to dampen the effects of predators on prey in many ecosystems. In marine systems, species at high trophic <span class="hlt">levels</span> are particularly susceptible to extinction (at least functionally). The loss of such species, which is mainly attributed to human activities (mostly fishing), is presently decreasing the diversity of marine predators in many areas of the world. Experimental studies that manipulate predator diversity and investigate the effects of this on strongly interactive consumers (i.e. those potentially capable of causing community-wide effects) in marine systems are scant, especially in the rocky sublittoral. I established an experiment that utilised cage enclosures to test whether the diversity and density of fish predators (two <span class="hlt">sea</span> breams and two wrasses) would <span class="hlt">affect</span> predation upon juvenile and adult <span class="hlt">sea</span> urchins, the most important grazers in Mediterranean sublittoral rocky reefs. Changes in species identity (with <span class="hlt">sea</span> breams producing major effects) and density of predators <span class="hlt">affected</span> predation upon <span class="hlt">sea</span> urchins more than changes in species richness per se. Predation upon adult <span class="hlt">sea</span> urchins decreased in the presence of multiple predators, probably due to interference competition between <span class="hlt">sea</span> breams and wrasses. This study suggests that factors that influence both fish predator diversity and density in Mediterranean rocky reefs (e.g. fishing and climate change) may have the potential to <span class="hlt">affect</span> the predators' ability to control <span class="hlt">sea</span> urchin population density, with possible repercussions for the whole benthic community structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMGC31A1023K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMGC31A1023K"><span>Holocene <span class="hlt">Sea-Level</span> Database For The Caribbean Region</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khan, N. S.; Horton, B.; Engelhart, S. E.; Peltier, W. R.; Scatena, F. N.; Vane, C. H.; Liu, S.</p> <p>2013-12-01</p> <p>Holocene relative <span class="hlt">sea-level</span> (RSL) records from far-field locations are important for understanding the driving mechanisms controlling the nature and timing of the mid-late Holocene reduction in global meltwaters and providing background rates of late Holocene RSL change with which to compare the magnitude of 20th century RSL rise. The Caribbean region has traditionally been considered far-field (i.e., with negligible glacio-isostatic adjustment (GIA) influence), although recent investigations indicate otherwise. Here, we consider the spatial variability in glacio-isostatic, tectonic and local contributions on RSL records from the circum-Caribbean region to infer a Holocene eustatic <span class="hlt">sea-level</span> signal. We have constructed a database of quality-controlled, spatially comprehensive, Holocene RSL observations for the circum-Caribbean region. The database contains over 500 index points, which locate the position of RSL in time and space. The database incorporates <span class="hlt">sea-level</span> observations from a latitudinal range of 5°N to 25°N and longitudinal range of 55°W to 90°W. We include <span class="hlt">sea-level</span> observations from 11 ka BP to present, although the majority of the index points in the database are younger than 8 ka BP. The database is sub-divided into 13 regions based on the distance from the former Laurentide Ice Sheet and regional tectonic setting. The index points were primarily derived from mangrove peat deposits, which in the Caribbean form in the upper half of the tidal range, and corals (predominantly Acropora palmata), the growth of which is constrained to the upper 5 m of water depth. The index points are classified on the basis of their susceptibility to compaction (e.g., intercalated, basal). The influence of temporal changes in tidal range on index points is also considered. The <span class="hlt">sea-level</span> reconstructions demonstrate that RSL did not exceed the present height (0 m) during the Holocene in the majority of locations, except at sites in Suriname/Guayana and possibly Trinidad</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA.....8435A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA.....8435A"><span><span class="hlt">Sea</span> <span class="hlt">level</span> during roman epoch in the central Tyrrhenian <span class="hlt">sea</span> (Italy)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Anzidei, M.; Antonioli, F.; Benini, A.; Esposito, A.; Lambeck, K.; Surace, L.</p> <p>2003-04-01</p> <p>The aim of this research is to reconstruct the vertical deformations of the earth's crust and the relative <span class="hlt">sea</span> <span class="hlt">level</span> oscillations during late Holocene (2-3 ka BP) by means of multidisciplinary investigations of archaeological sites located along the central Tyrrhenian coastlines (Italy). The sites (piscinae, harbours and quarries) of pre-Roman and Roman Age, play a fundamental role for the evaluation of the <span class="hlt">sea</span> <span class="hlt">level</span> rise during the last 2.5 ka. Early studies using this technique were performed by Flemming (1969), Schmiedt (1972), Pirazzoli (1976) and more recently by Flemming and Webb (1986) and Leoni and Dai Pra (1997). We have used the original latin sources written by the historical Roman authors Varrone and Columella to understand the detailed technical rules for the construction of the piscinae (depth of ponds and channels, operating range of the sluice gates, etc.). On the basis of these publications we re-interpret some significant sites to estimate the difference between their ancient depths and some recent interpretations. We studied the remains located at Castiglioncello, Gravisca, Punta della Vipera, Santa Marinella, Torre Astura and Ventotene island. Our data show an increase in <span class="hlt">sea</span> <span class="hlt">level</span> at these sites of between 178±20 and 125±20 cm since pre-roman age (2.3-1.9 ka BP). All sites are located along about 400 km coastline of the Tyrrhenian <span class="hlt">sea</span>, from Tuscany to Latium, that exhibits areas of both tectonic stability and instability and we use the elevation of the MIS 5.5 transgression (inner margin sediments) to estimate the rates of uplift or subsidence. At Punta della Vipera this elevation reaches 35 m (Antonioli et al., 2000) and we consider that this area has been tectonically active with an uplift rate of 0.23 ± 0.05 mm yr-1. High resolution numerical models of <span class="hlt">sea-level</span> change have been used and tested against other Italian <span class="hlt">sea</span> <span class="hlt">level</span> data to provide a realistic representation of the spatial variability of the <span class="hlt">sea-level</span> change and shoreline</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/1000866','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/1000866"><span>Chemosterilization of male <span class="hlt">sea</span> lampreys (Petromyzon marinus) does not <span class="hlt">affect</span> sex pheromone release</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Siefkes, Michael J.; Bergstedt, Roger A.; Twohey, Michael B.; Li, Weiming</p> <p>2003-01-01</p> <p>Release of males sterilized by injection with bisazir is an important experimental technique in management of <span class="hlt">sea</span> lamprey (Petromyzon marinus), an invasive, nuisance species in the Laurentian Great Lakes. <span class="hlt">Sea</span> lampreys are semelparous and sterilization can theoretically eliminate a male's reproductive capacity and, if the ability to obtain mates is not <span class="hlt">affected</span>, waste the sex products of females spawning with him. It has been demonstrated that spermiating males release a sex pheromone that attracts ovulating females. We demonstrated that sterilized, spermiating males also released the pheromone and attracted ovulating females. In a two-choice maze, ovulating females increased searching behavior and spent more time in the side of the maze containing chemical stimuli from sterilized, spermiating males. This attraction response was also observed in spawning stream experiments. Also, electro-olfactograms showed that female olfactory organs were equally sensitive to chemical stimuli from sterilized and nonsterilized, spermiating males. Finally, fast atom bombardment mass spectrometry showed that extracts from water conditioned with sterilized and nonsterilized, spermiating males contained the same pheromonal molecule at similar <span class="hlt">levels</span>. We concluded that injection of bisazir did not <span class="hlt">affect</span> the efficacy of sex pheromone in sterilized males.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28240439','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28240439"><span>Using environmental heterogeneity to plan for <span class="hlt">sea-level</span> rise.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hunter, Elizabeth A; Nibbelink, Nathan P</p> <p>2017-02-27</p> <p>Environmental heterogeneity is increasingly being used to select conservation areas that will provide for future biodiversity under a variety of climate scenarios. This approach, termed "conserving nature's stage" (CNS), assumes that environmental features will respond to climate change more slowly than biological communities, but is CNS effective when the stage is changing as rapidly as the climate? We tested the effectiveness of CNS to select conservation sites in salt marshes in coastal Georgia, USA, where environmental features will change rapidly due to <span class="hlt">sea</span> <span class="hlt">level</span> rise (SLR). We calculated species diversity using distributions of a group of seven bird species with a wide variety of niches within Georgia salt marshes. Environmental heterogeneity was assessed across six landscape gradients (e.g., elevation, salinity, and patch area). We selected sites with high environmental heterogeneity using two approaches: a site complementarity approach ("Environmental Diversity" [ED]) and an approach that favors local environmental heterogeneity ("Environmental Richness" [ER]). We found that ER-selected sites could predict present-day species diversity better than randomly selected sites (up to an 8.1% improvement), while also being resilient to areal loss from SLR, and providing habitat to a particularly at-risk species. ED-selected sites did not perform well (no better or worse than random) in terms of predicting species diversity and will not be resilient to SLR. Despite the discrepancy between the two approaches, CNS is a viable strategy for conservation site selection in salt marshes, and potentially other coastal areas where SLR will <span class="hlt">affect</span> environmental features, but performance may depend on the magnitude of geological changes caused by SLR. Our results indicate that conservation planners using CNS that had heretofore ignored low-lying coasts (due to concerns of SLR) could include coastal ecosystems in regional planning strategies. This article is protected by</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006GeoRL..3314606Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006GeoRL..3314606Z"><span>Annual <span class="hlt">sea</span> <span class="hlt">level</span> amphidromes in the South China <span class="hlt">Sea</span> revealed by merged altimeter data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Caiyun; Wang, Bin; Chen, Ge</p> <p>2006-07-01</p> <p>Annual phase-amplitude characteristics of <span class="hlt">sea</span> <span class="hlt">level</span> anomaly (SLA) in the South China <span class="hlt">Sea</span> (SCS) are investigated by a merged SLA data set derived from simultaneous measurements of Envisat, Geosat-Follow-on (GFO), Jason-1, and TOPEX/Poseidon (T/P) from January 2004 to December 2005. Four annual amphidromes instead of two are revealed and their locations, surrounding the Vietnam eddy, distinguish two distinctive regimes of annual variations in the SCS, a basin scale monsoon regime and a local Vietnam eddy regime. Their existence suggests that the annual amphidrome is not only a common feature on global scale, but also a phenomenon in regional <span class="hlt">seas</span>. However, the locations of these amphidromes in the SCS vary considerably from year to year, in contrast to the annual amphidomes found in the tropical ocean basins, which are much more stable.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ChJOL..35...79Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ChJOL..35...79Q"><span>Interannual to decadal variation of spring <span class="hlt">sea</span> <span class="hlt">level</span> anomaly in the western South China <span class="hlt">Sea</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Qiu, Fuwen; Fang, Wendong; Pan, Aijun; Cha, Jing; Zhang, Shanwu; Huang, Jiang</p> <p>2017-01-01</p> <p>Satellite observations of <span class="hlt">sea</span> <span class="hlt">level</span> anomalies (SLA) from January 1993 to December 2012 are used to investigate the interannual to decadal changes of the boreal spring high SLA in the western South China <span class="hlt">Sea</span> (SCS) using the Empirical Orthogonal Function (EOF) method. We find that the SLA variability has two dominant modes. The <span class="hlt">Sea</span> <span class="hlt">Level</span> Changing Mode (SLCM) occurs mainly during La Niña years, with high SLA extension from west of Luzon to the eastern coast of Vietnam along the central basin of the SCS, and is likely induced by the increment of the ocean heat content. The Anticyclonic Eddy Mode (AEM) occurs mainly during El Niño years and appears to be triggered by the negative wind curl anomalies within the central SCS. In addition, the spring high SLA in the western SCS experienced a quasi-decadal change during 1993-2012; in other words, the AEM predominated during 1993-1998 and 2002-2005, while the La Niña-related SLCM prevailed during 1999-2001 and 2006-2012. Moreover, we suggest that the accelerated <span class="hlt">sea</span> <span class="hlt">level</span> rise in the SCS during 2005-2012 makes the SLCM the leading mode over the past two decades.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMPP33C1260P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMPP33C1260P"><span>Quaternary <span class="hlt">Sea-Level</span> History from the US Atlantic Coastal Plain</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Poirier, R. K.; Cronin, T. M.; Katz, M. E.; Browning, J. V.; Miller, K. G.; Willard, D. A.</p> <p>2014-12-01</p> <p>Analyses of emerged Quaternary paleo-shorelines and marine deposits aid in the reconstruction of environmental conditions and variability surrounding recent ice volume and <span class="hlt">sea-level</span> histories derived from oxygen isotope records. We present preliminary results from a project designed to analyze the age, elevation, and paleoclimate history of Quaternary sediments deposited during <span class="hlt">sea</span> <span class="hlt">level</span> highstands along the United States Atlantic Coastal Plain (ACP) from Maryland to Florida. Prior studies have shown that, depending on the region, ACP sediments correlate with past interglacial periods corresponding to Marine Isotope Stages (MIS) 5, 7, possibly 9, and 11. Stratigraphy, marine micropaleontology, and palynology indicate at least two major marine transgressive sequences on the Delmarva Peninsula in Virginia corresponding to MIS 5a and 11, the Nassawadox Formation and Accomack beds of the Omar Formation, respectively. These depositional sequences represent <span class="hlt">sea-level</span> positions of approximately +10m and +15m, relative to today. Despite generally corresponding to glacio-eustatic <span class="hlt">sea</span> <span class="hlt">levels</span> of +5-9m for MIS 5a-e (Potter & Lambeck, 2003; Kopp et al., 2009), and of +6-13m for MIS 11 (Raymo & Mitrovica, 2012), the relative <span class="hlt">sea-level</span> positions during both interglacial periods were likely <span class="hlt">affected</span> by glacio-isostatic adjustment in the region. Corresponding marine units and paleo-shorelines, identified by pronounced inland scarps separated by intermittent terraces on the western side of the Chesapeake Bay, are likely from MIS 5, 7, and 11. Ostracode and foraminifera assemblages identify significant environmental variability within these transgressive interglacial deposits, likely driven by relatively minor, suborbital climatic and <span class="hlt">sea-level</span> oscillations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70011660','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70011660"><span>Holocene changes in <span class="hlt">sea</span> <span class="hlt">level</span>: Evidence in Micronesia</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Shepard, F.P.; Curray, Joseph R.; Newman, W.A.; Bloom, A.L.; Newell, N.D.; Tracey, J.I.; Veeh, H.H.</p> <p>1967-01-01</p> <p>Investigation of 33 islands, scattered widely across the Caroline and Marshall Island groups in the Central Pacific revealed no emerged reefs in which corals had unquestionably formed in situ, or other direct evidence of postglacial high stands of <span class="hlt">sea</span> <span class="hlt">level</span>. Low unconsolidated rock terraces and ridges of reef-flat islands, mostly lying between tide <span class="hlt">levels</span>, were composed of rubble conglomerates; carbon-14 dating of 11 samples from the conglomerates so far may suggest a former slightly higher <span class="hlt">sea</span> <span class="hlt">level</span> (nine samples range between 1890 and 3450 and one approaches 4500 years ago). However, recent hurricanes have produced ridges of comparable height and material, and in the same areas relics from World War II have been found cemented in place. Thus these datings do not in themselves necessarily indicate formerly higher <span class="hlt">sea</span> <span class="hlt">levels</span>. Rubble tracts are produced by storms under present conditions without any change in datum, and there seems to be no compelling evidence that they were not so developed during various periods in the past.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009ERL.....4d1001H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009ERL.....4d1001H"><span>PERSPECTIVE: The tripping points of <span class="hlt">sea</span> <span class="hlt">level</span> rise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hecht, Alan D.</p> <p>2009-12-01</p> <p>When President Nixon created the US Environmental Protection Agency (EPA) in 1970 he said the environment must be perceived as a single, interrelated system. We are nowhere close to achieving this vision. Jim Titus and his colleagues [1] highlight one example of where one set of regulations or permits may be in conflict with another and where regulations were crafted in the absence of understanding the cumulative impact of global warming. The issue here is how to deal with the impacts of climate change on <span class="hlt">sea</span> <span class="hlt">level</span> and the latter's impact on wetland polices, clean water regulations, and ecosystem services. The Titus paper could also be called `The tripping points of <span class="hlt">sea</span> <span class="hlt">level</span> rise'. Titus and his colleagues have looked at the impact of such <span class="hlt">sea</span> <span class="hlt">level</span> rise on the east coast of the United States. Adaptive responses include costly large- scale investment in shore protection (e.g. dikes, sand replenishment) and/or ecosystem migration (retreat), where coastal ecosystems move inland. Shore protection is limited by available funds, while ecosystem migrations are limited by available land use. The driving factor is the high probability of <span class="hlt">sea</span> <span class="hlt">level</span> rise due to climate change. Estimating <span class="hlt">sea</span> <span class="hlt">level</span> rise is difficult because of local land and coastal dynamics including rising or falling land areas. It is estimated that <span class="hlt">sea</span> <span class="hlt">level</span> could rise between 8 inches and 2 feet by the end of this century [2]. The extensive data analysis done by Titus et al of current land use is important because, as they observe, `property owners and land use agencies have generally not decided how they will respond to <span class="hlt">sea</span> <span class="hlt">level</span> rise, nor have they prepared maps delineating where shore protection and retreat are likely'. This is the first of two `tripping points', namely the need for adaptive planning for a pending environmental challenge that will create economic and environment conflict among land owners, federal and state agencies, and businesses. One way to address this gap in adaptive management</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.G43B1041J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.G43B1041J"><span><span class="hlt">Sea</span> <span class="hlt">Level</span> Variability in the Coastal Ocean Induced by Atmospheric Forcing for the Period 1871-2012</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jorda, G.; Compo, G. P.; Nerem, R. S.; Lyard, F.</p> <p>2015-12-01</p> <p>Global mean <span class="hlt">sea</span> <span class="hlt">level</span> (GMSL) is the preferred proxy to assess changes in the ocean heat and freshwater content as it is less <span class="hlt">affected</span> by internal variability that regional <span class="hlt">sea</span> <span class="hlt">level</span> (Cazenave and Nerem, 2004). However, what really matters for society is the variability of <span class="hlt">sea</span> <span class="hlt">level</span> at regional scales as the impact of <span class="hlt">sea</span> <span class="hlt">level</span> variations occur at those scales. Regional <span class="hlt">sea</span> <span class="hlt">level</span> (RSL) is not only <span class="hlt">affected</span> by the same processes that GMSL (thermal expansion/contraction and water addition/removal) but also by the redistribution of mass. In particular, due to atmospheric forcing (i.e. atmospheric <span class="hlt">sea</span> <span class="hlt">level</span> pressure and wind stress) is the principal mechanism for the water redistribution in the ocean and accounts for a large fraction of the coastal <span class="hlt">sea</span> <span class="hlt">level</span> variance. In particular, it is the dominant mechanism for the variability in the subtidal to intraseasonal range (i.e. from days to months). This includes storm surge events, which are responsible for the largest damages in coastal regions. At frequencies from seasonal to interannual, its relevance is comparable to the steric contribution, specially at high and low latitudes (Fukumori et al. 1998). For the decadal to multidecadal range it is usually assumed that it has a secondary role, but this has not yet been studied in depth. In this presentation we will show the results obtained from a new global simulation of atmospherically induced <span class="hlt">sea</span> <span class="hlt">level</span> variability for the period 1871-2012. This simulation uses the NOAA Twentieth Century Reanalysis (Compo et al., 2011) to force a global ocean barotropic model (TUGO, Carrère and Lyard, 2003). We will focus on the description of the impact of mass redistribution on coastal <span class="hlt">sea</span> <span class="hlt">level</span> variability at interannual to multidecadal scales and from a global perspective. We will also show how this mass redistribution can induce errors in GMSL trends and accelerations derived from tide gauge reconstructions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17801535','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17801535"><span>Milankovitch forcing of the last interglacial <span class="hlt">sea</span> <span class="hlt">level</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Crowley, T J; Kim, K Y</p> <p>1994-09-09</p> <p>During the last interglacial, <span class="hlt">sea</span> <span class="hlt">level</span> was as high as present, 4000 to 6000 years before peak Northern Hemisphere insolation receipt 126,000 years ago. The <span class="hlt">sea-level</span> results are shown to be consistent with climate models, which simulate a 3 degrees to 4 degrees C July temperature increase from 140,000 to 130,000 years ago in high latitudes, with all Northern Hemisphere land areas being warmer than present by 130,000 years ago. The early warming occurs because obliquity peaked earlier than precession and because precession values were greater than present before peak precessional forcing occurred. These results indicate that a fuller understanding of the Milankovitch-climate connection requires consideration of fields other than just insolation forcing at 65 degrees N.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999EOSTr..80..103G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999EOSTr..80..103G"><span>Holocene Antarctic's coastal environment, ice sheet, and <span class="hlt">sea</span> <span class="hlt">levels</span> explored</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Goodwin, I.; Berkman, P.; Hjort, C.; Hirakawa, K.</p> <p></p> <p>Efforts are in the works to resolve a several-decade-long debate over the size and extent of the Antarctic ice sheet and its role in <span class="hlt">sea</span> <span class="hlt">levels</span> during the last glacial cycle. Researchers also want to find out more about the nature of environmental changes around the Antarctic coast throughout the Holocene, the sensitivity of the ice sheet to warm periods, and the significance of pre-Holocene marine fossils there.Scientists concerned with these issues presented their research priorities last fall at an Antarctic ice margin evolution (ANTIME) workshop, “Circum-Antarctic Coastal Environmental Variability and <span class="hlt">Sea</span> <span class="hlt">Level</span> History During the Late Quaternary.” These workshop participants included coastal and glacial geomorphologists, geochemists, and paleoecologists.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70013881','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70013881"><span>Contribution of small glaciers to global <span class="hlt">sea</span> <span class="hlt">level</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Meier, M.F.</p> <p>1984-01-01</p> <p>Observed long-term changes in glacier volume and hydrometeorological mass balance models yield data on the transfer of water from glaciers, excluding those in Greenland and Antarctica, to the oceans, The average observed volume change for the period 1900 to 1961 is scaled to a global average by use of the seasonal amplitude of the mass balance. These data are used to calibrate the models to estimate the changing contribution of glaciers to <span class="hlt">sea</span> <span class="hlt">level</span> for the period 1884 to 1975. Although the error band is large, these glaciers appear to accountfor a third to half of observed rise in <span class="hlt">sea</span> <span class="hlt">level</span>, approximately that fraction not explained by thermal expansion of the ocean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4978990','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4978990"><span>Is the detection of accelerated <span class="hlt">sea</span> <span class="hlt">level</span> rise imminent?</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Fasullo, J. T.; Nerem, R. S.; Hamlington, B.</p> <p>2016-01-01</p> <p>Global mean <span class="hlt">sea</span> <span class="hlt">level</span> rise estimated from satellite altimetry provides a strong constraint on climate variability and change and is expected to accelerate as the rates of both ocean warming and cryospheric mass loss increase over time. In stark contrast to this expectation however, current altimeter products show the rate of <span class="hlt">sea</span> <span class="hlt">level</span> rise to have decreased from the first to second decades of the altimeter era. Here, a combined analysis of altimeter data and specially designed climate model simulations shows the 1991 eruption of Mt Pinatubo to likely have masked the acceleration that would have otherwise occurred. This masking arose largely from a recovery in ocean heat content through the mid to late 1990 s subsequent to major heat content reductions in the years following the eruption. A consequence of this finding is that barring another major volcanic eruption, a detectable acceleration is likely to emerge from the noise of internal climate variability in the coming decade. PMID:27506974</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=350421','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=350421"><span>Relative <span class="hlt">sea</span> <span class="hlt">levels</span> from tide-gauge records</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Emery, K. O.</p> <p>1980-01-01</p> <p>Mean annual <span class="hlt">sea</span> <span class="hlt">levels</span> at 247 tide-gauge stations of the world exhibit a general rise of relative <span class="hlt">sea</span> <span class="hlt">level</span> of about 3 mm/year during the past 40 years. In contrast, general uplift of the land is typical of high northern latitudes, where unloading of the crust by melt of Pleistocene ice sheets is significant. Erratic movements are typical of belts having crustal overthrusting and active volcanism. Short-term (5- and 10-year) records reveal recent changes in rates, but such short time spans may be so influenced by climatic cycles that identification of new trends is difficult, especially with the existing poor distribution and reporting of tide-gauge data. Images PMID:16592929</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014GeoRL..41.4970R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014GeoRL..41.4970R"><span>Control of Quaternary <span class="hlt">sea-level</span> changes on gas seeps</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Riboulot, Vincent; Thomas, Yannick; Berné, Serge; Jouet, Gwénaël.; Cattaneo, Antonio</p> <p>2014-07-01</p> <p>Gas seeping to the seafloor through structures such as pockmarks may contribute significantly to the enrichment of atmospheric greenhouse gases and global warming. Gas seeps in the Gulf of Lions, Western Mediterranean, are cyclical, and pockmark "life" is governed both by sediment accumulation on the continental margin and Quaternary climate changes. Three-dimensional seismic data, correlated to multi-proxy analysis of a deep borehole, have shown that these pockmarks are associated with oblique chimneys. The prograding chimney geometry demonstrates the syn-sedimentary and long-lasting functioning of the gas seeps. Gas chimneys have reworked chronologically constrained stratigraphic units and have functioned episodically, with maximum activity around <span class="hlt">sea</span> <span class="hlt">level</span> lowstands. Therefore, we argue that one of the main driving mechanisms responsible for their formation is the variation in hydrostatic pressure driven by relative <span class="hlt">sea</span> <span class="hlt">level</span> changes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6481137','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6481137"><span>Relative <span class="hlt">sea</span> <span class="hlt">levels</span> from tide-gauge records</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Emery, K.O.</p> <p>1980-12-01</p> <p>Mean annual <span class="hlt">sea</span> <span class="hlt">levels</span> at 247 tide-gauge stations of the world exhibit a general rise of relative <span class="hlt">sea</span> <span class="hlt">level</span> of about 3 mm/year during the past 40 years. In contrast, general uplift of the land is typical of high northern latitudes, where unloading of the crust by melt of Pleistocene ice sheets is significant. Erratic movements are typical of belts having crustal overthrusting and active volcanism. Short-term (5- and 10-year) records reveal recent changes in rates, but such short time spans may be so influenced by climatic cycles that identification of new trends is difficult, especially with the existing poor distribution and reporting of tide-gauge data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27506974','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27506974"><span>Is the detection of accelerated <span class="hlt">sea</span> <span class="hlt">level</span> rise imminent?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fasullo, J T; Nerem, R S; Hamlington, B</p> <p>2016-08-10</p> <p>Global mean <span class="hlt">sea</span> <span class="hlt">level</span> rise estimated from satellite altimetry provides a strong constraint on climate variability and change and is expected to accelerate as the rates of both ocean warming and cryospheric mass loss increase over time. In stark contrast to this expectation however, current altimeter products show the rate of <span class="hlt">sea</span> <span class="hlt">level</span> rise to have decreased from the first to second decades of the altimeter era. Here, a combined analysis of altimeter data and specially designed climate model simulations shows the 1991 eruption of Mt Pinatubo to likely have masked the acceleration that would have otherwise occurred. This masking arose largely from a recovery in ocean heat content through the mid to late 1990 s subsequent to major heat content reductions in the years following the eruption. A consequence of this finding is that barring another major volcanic eruption, a detectable acceleration is likely to emerge from the noise of internal climate variability in the coming decade.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011EOSTr..92Q.408S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011EOSTr..92Q.408S"><span>Groundwater depletion's contribution to <span class="hlt">sea</span> <span class="hlt">level</span> rise increasing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schultz, Colin</p> <p>2011-11-01</p> <p>Since the turn of the twentieth century, industrial-scale redistribution of water from landlocked aquifers to the ocean has driven up the global average <span class="hlt">sea</span> <span class="hlt">level</span> by more than 12 centimeters. Between 1900 and 2008, roughly 4500 cubic kilometers of water was drawn from the ground, largely to feed an agricultural system increasingly reliant on irrigation. Of that 4500-cubic-kilometer total (nearly the volume of Lake Michigan), 1100 cubic kilometers were pumped out between 2000 and 2008 alone. This early-21st-century groundwater depletion was responsible for raising global <span class="hlt">sea</span> <span class="hlt">level</span> at a rate of 0.4 millimeter per year, an eighth of the observed total. These updated values, falling near the middle of the range of previous estimates, are the product of an investigation by Konikow that drew together a variety of volumetric measurements of groundwater storage.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70014916','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70014916"><span>The record of Pliocene <span class="hlt">sea-level</span> change at Enewetak Atoll</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Wardlaw, B.R.; Quinn, T.M.</p> <p>1991-01-01</p> <p>Detailed seismic stratigraphy, lithostratigraphy, and chemostratigraphy indicate that atoll-wide subaerial exposure surfaces (major disconformities) developed during major <span class="hlt">sea-level</span> lowstands form prominent seismic reflectors and are coincident with biostratigraphic breaks in the Plio-Pleistocene on Enewetak Atoll. <span class="hlt">Sea-level</span> models based on the stratigraphic position and age of major disconformities suggest a maximum <span class="hlt">sea-level</span> highstand elevation of 36 m above present <span class="hlt">sea</span> <span class="hlt">level</span> and a maximum <span class="hlt">sea-level</span> lowstand elevation of 63 m below present <span class="hlt">sea</span> <span class="hlt">level</span> for the Pliocene. ?? 1991.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1991QSRv...10..247W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1991QSRv...10..247W"><span>The record of Pliocene <span class="hlt">sea-level</span> change at Enewetak Atoll</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wardlaw, Bruce R.; Quinn, Terrence M.</p> <p></p> <p>Detailed seismic stratigraphy, lithostratigraphy, and chemostratigraphy indicate that atoll-wide subaerial exposure surfaces (major disconformities) developed during major <span class="hlt">sea-level</span> lowstands form prominent seismic reflectors and are coincident with biostratigraphic breaks in the Plio-Pleistocene on Enewetak Atoll. <span class="hlt">Sea-level</span> models based on the stratigraphic position and age of major disconformities suggest a maximum <span class="hlt">sea-level</span> highstand elevation of 36 m above present <span class="hlt">sea</span> <span class="hlt">level</span> and a maximum <span class="hlt">sea-level</span> lowstand elevation of 63 m below present <span class="hlt">sea</span> <span class="hlt">level</span> for the Pliocene.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12..126C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12..126C"><span><span class="hlt">Sea</span> <span class="hlt">level</span> change impacts on the coastal infrastructures of the Basque Coast</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Caballero, Ainhoa; Chust, Guillem; Liria, Pedro; Marcos, Marta</p> <p>2010-05-01</p> <p> ports will decrease (in some cases the distance will be less than 30 cm); with the subsequent diminish of these piers functionality. In order to evaluate the impact on external dikes, besides <span class="hlt">sea</span> <span class="hlt">level</span> rise, predicted wave height change has been taken into account. The estimations of the overtopping over a model dike, under the oceanographic conditions <span class="hlt">affecting</span> the main real external dikes, suggest an increasing overtopping of these model dikes for the end of this century. Keywords: <span class="hlt">sea</span> <span class="hlt">level</span> rise, climate change, coast, impacts, infrastructures Session: OS10; <span class="hlt">Sea</span> <span class="hlt">level</span> change and its impact in coastal oceans References: - Cearreta, A., Irabien, M.J., Pascual, A., 2004. Human activities along the Basque coast during the last two centuries: geological perspective of recent anthropogenic impact on the coast and its environmental consequences. In: Borja, A., Collins, M. (Eds.), Oceanography and Marine Environment of the Basque Country. Elsevier Oceanography Series, vol. 70, pp. 27-50. - Chust, G., Borja, A., Liria, P., Galparsoro, I., Marcos, M., Caballero, A., Castro, R., 2009. Human impacts overwhelm the effects of <span class="hlt">sea-level</span> rise on Basque coastal habitats (N Spain) between 1954 and 2004. Estuarine, Coastal and Shelf Science, 84, 453-462.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ECSS..163..185H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ECSS..163..185H"><span>Coastal wetland response to <span class="hlt">sea</span> <span class="hlt">level</span> rise in Connecticut and New York</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hill, Troy D.; Anisfeld, Shimon C.</p> <p>2015-09-01</p> <p>The persistence of salt marshes in the landscape depends on their ability to accommodate rising <span class="hlt">sea</span> <span class="hlt">level</span> and minimize additional flooding stress. We use sediment cores and water <span class="hlt">level</span> data from 14 marshes in Connecticut and New York to evaluate how marsh accretion, mineral and organic accumulation, carbon storage, and hydroperiod have changed from 1900 to 2012. We observe a regional acceleration in marsh accretion beginning around 1940, although marsh accretion did not reach parity with <span class="hlt">sea</span> <span class="hlt">level</span> rise for several additional decades. Despite a rise in marsh accretion from 1.0 mm yr-1 circa 1900 to 3.6 mm yr-1 at present, the marsh surface has lost elevation relative to tidal datums. Declining relative elevations have led to increased tidal flooding, particularly in high marsh settings. As flooding increased, organic matter accumulation accelerated at all marshes. Accelerating mineral deposition was only observed in areas of short-form Spartina alterniflora. Mineral and organic sediment accumulation co-limit accretion, but organic accumulation was the stronger limiting factor, suggesting that marsh response to <span class="hlt">sea</span> <span class="hlt">level</span> rise in the region is sensitive to processes <span class="hlt">affecting</span> rates of belowground production and decomposition. Marsh carbon storage over the period of study averaged 84 g C m-2 yr-1, increasing as accretion accelerated. If marshes remain spatially intact as <span class="hlt">sea</span> <span class="hlt">levels</span> rise, these results suggest that marshes have the capacity to become even greater C sinks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5946008','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5946008"><span>Land subsidence and <span class="hlt">sea</span> <span class="hlt">level</span> rise on the Atlantic Coastal Plain of the United States</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Davis, G.H.</p> <p>1987-01-01</p> <p>Land subsidence due to decline in head in confined aquifers, related to municipal and industrial water pumpage, is widespread in the Atlantic Coastal Plain. Although not a major engineering problem, subsidence greatly complicates adjustment of precise <span class="hlt">leveling</span> and distorts prediction of future <span class="hlt">sea-level</span> rise. When preconsolidation stress equivalent to about 20 m of head decline is exceeded compaction of fine-grained sediments of the aquifer system begins, and continuous until a new head equilibrium is attained between fine and coarse units. The ratio subsidence/head decline is quite consistent, ranging form 0.0064 in southeastern Virginia to 0.0018 at Dover, Delaware and Atlantic City, New Jersey. Higher values are related to the occurrence of montmorillonite as the predominant clay mineral present. Review of tide gauge records indicates that gauges not <span class="hlt">affected</span> by land subsidence or other local secular effects have been sinking relative to <span class="hlt">sea</span> <span class="hlt">level</span> since 1940 at rates averaging about 2.5 mm/yr. of which 0.6 mm/yr is ascribed to glacio-isostatic adjustment to unloading of North America resulting from melting of late Pleistocene glaciers, and about 0.9 mm/yr is ascribed to steric <span class="hlt">sea-level</span> rise related to ocean warming. The residual 1 mm/yr of relative <span class="hlt">sea-level</span> rise is not well understood, but may be related to regional tectonic subsidence of the Atlantic coast.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMIN41B3656J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMIN41B3656J"><span>The Future of GLOSS <span class="hlt">Sea</span> <span class="hlt">Level</span> Data Archaeology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jevrejeva, S.; Bradshaw, E.; Tamisiea, M. E.; Aarup, T.</p> <p>2014-12-01</p> <p>Long term climate records are rare, consisting of unique and unrepeatable measurements. However, data do exist in analogue form in archives, libraries and other repositories around the world. The Global <span class="hlt">Sea</span> <span class="hlt">Level</span> Observing System (GLOSS) Group of Experts aims to provide advice on locating hidden tide gauge data, scanning and digitising records and quality controlling the resulting data. Long <span class="hlt">sea</span> <span class="hlt">level</span> data time series are used in Intergovernmental Panel on Climate Change (IPCC) assessment reports and climate studies, in oceanography to study changes in ocean currents, tides and storm surges, in geodesy to establish national datum and in geography and geology to monitor coastal land movement. GLOSS has carried out a number of data archaeology activities over the past decade, which have mainly involved sending member organisations questionnaires on their repositories. The Group of Experts is now looking at future developments in <span class="hlt">sea</span> <span class="hlt">level</span> data archaeology and how new technologies coming on line could be used by member organisations to make data digitisation and transcription more efficient. Analogue tide data comes in two forms charts, which record the continuous measurements made by an instrument, usually via a pen trace on paper ledgers containing written values of observations The GLOSS data archaeology web pages will provide a list of software that member organisations have reported to be suitable for the automatic digitisation of tide gauge charts. Transcribing of ledgers has so far proved more labour intensive and is usually conducted by people entering numbers by hand. GLOSS is exploring using Citizen Science techniques, such as those employed by the Old Weather project, to improve the efficiency of transcribing ledgers. The Group of Experts is also looking at recent advances in Handwritten Text Recognition (HTR) technology, which mainly relies on patterns in the written word, but could be adapted to work with the patterns inherent in <span class="hlt">sea</span> <span class="hlt">level</span> data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/fs/0091-97/report.pdf','USGSPUBS'); return false;" href="https://pubs.usgs.gov/fs/0091-97/report.pdf"><span>Global warming, <span class="hlt">sea-level</span> rise, and coastal marsh survival</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Cahoon, Donald R.</p> <p>1997-01-01</p> <p>Coastal wetlands are among the most productive ecosystems in the world. These wetlands at the land-ocean margin provide many direct benefits to humans, including habitat for commercially important fisheries and wildlife; storm protection; improved water quality through sediment, nutrient, and pollution removal; recreation; and aesthetic values. These valuable ecosystems will be highly vulnerable to the effects of the rapid rise in <span class="hlt">sea</span> <span class="hlt">level</span> predicted to occur during the next century as a result of global warming.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011GeoJI.186.1036T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011GeoJI.186.1036T"><span>Ongoing glacial isostatic contributions to observations of <span class="hlt">sea</span> <span class="hlt">level</span> change</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tamisiea, Mark E.</p> <p>2011-09-01</p> <p>Studies determining the contribution of water fluxes to <span class="hlt">sea</span> <span class="hlt">level</span> rise typically remove the ongoing effects of glacial isostatic adjustment (GIA). Unfortunately, use of inconsistent terminology between various disciplines has caused confusion as to how contributions from GIA should be removed from altimetry and GRACE measurements. In this paper, we review the physics of the GIA corrections applicable to these measurements and discuss the differing nomenclature between the GIA literature and other studies of <span class="hlt">sea</span> <span class="hlt">level</span> change. We then examine a range of estimates for the GIA contribution derived by varying the Earth and ice models employed in the prediction. We find, similar to early studies, that GIA produces a small (compared to the observed value) but systematic contribution to the altimetry estimates, with a maximum range of -0.15 to -0.5 mm yr-1. Moreover, we also find that the GIA contribution to the mass change measured by GRACE over the ocean is significant. In this regard, we demonstrate that confusion in nomenclature between the terms 'absolute <span class="hlt">sea</span> <span class="hlt">level</span>' and 'geoid' has led to an overestimation of this contribution in some previous studies. A component of this overestimation is the incorrect inclusion of the direct effect of the contemporaneous perturbations of the rotation vector, which leads to a factor of ˜two larger value of the degree two, order one spherical harmonic component of the model results. Aside from this confusion, uncertainties in Earth model structure and ice sheet history yield a spread of up to 1.4 mm yr-1 in the estimates of this contribution. However, even if the ice and Earth models were perfectly known, the processing techniques used in GRACE data analysis can introduce variations of up to 0.4 mm yr-1. Thus, we conclude that a single-valued 'GIA correction' is not appropriate for <span class="hlt">sea</span> <span class="hlt">level</span> studies based on gravity data; each study must estimate a bound on the GIA correction consistent with the adopted data-analysis scheme.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.8447M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.8447M"><span>Mean Tide <span class="hlt">Level</span> Data in the PSMSL Mean <span class="hlt">Sea</span> <span class="hlt">Level</span> Dataset</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Matthews, Andrew; Bradshaw, Elizabeth; Gordon, Kathy; Jevrejeva, Svetlana; Rickards, Lesley; Tamisiea, Mark; Williams, Simon; Woodworth, Philip</p> <p>2016-04-01</p> <p>The Permanent Service for Mean <span class="hlt">Sea</span> <span class="hlt">Level</span> (PSMSL) is the internationally recognised global <span class="hlt">sea</span> <span class="hlt">level</span> data bank for long term <span class="hlt">sea</span> <span class="hlt">level</span> change information from tide gauges. Established in 1933, the PSMSL continues to be responsible for the collection, publication, analysis and interpretation of <span class="hlt">sea</span> <span class="hlt">level</span> data. The PSMSL operates under the auspices of the International Council for Science (ICSU), is a regular member of the ICSU World Data System and is associated with the International Association for the Physical Sciences of the Oceans (IAPSO) and the International Association of Geodesy (IAG). The PSMSL continues to work closely with other members of the <span class="hlt">sea</span> <span class="hlt">level</span> community through the Intergovernmental Oceanographic Commission's Global <span class="hlt">Sea</span> <span class="hlt">Level</span> Observing System (GLOSS). Currently, the PSMSL data bank holds over 67,000 station-years of monthly and annual mean <span class="hlt">sea</span> <span class="hlt">level</span> data from over 2250 tide gauge stations. Data from each site are quality controlled and, wherever possible, reduced to a common datum, whose stability is monitored through a network of geodetic benchmarks. PSMSL also distributes a data bank of measurements taken from in-situ ocean bottom pressure recorders. Most of the records in the main PSMSL dataset indicate mean <span class="hlt">sea</span> <span class="hlt">level</span> (MSL), derived from high-frequency tide gauge data, with sampling typically once per hour or higher. However, some of the older data is based on mean tide <span class="hlt">level</span> (MTL), which is obtained from measurements taken at high and low tide only. While usually very close, MSL and MTL can occasionally differ by many centimetres, particularly in shallow water locations. As a result, care must be taken when using long <span class="hlt">sea</span> <span class="hlt">level</span> records that contain periods of MTL data. Previously, periods during which the values indicated MTL rather than MSL were noted in the documentation, and sometimes suggested corrections were supplied. However, these comments were easy to miss, particularly in large scale studies that used multiple stations from across</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/638181','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/638181"><span>Glacier calving, dynamics, and <span class="hlt">sea-level</span> rise. Final report</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Meier, M.F.; Pfeffer, W.T.; Amadei, B.</p> <p>1998-08-01</p> <p>The present-day calving flux from Greenland and Antarctica is poorly known, and this accounts for a significant portion of the uncertainty in the current mass balance of these ice sheets. Similarly, the lack of knowledge about the role of calving in glacier dynamics constitutes a major uncertainty in predicting the response of glaciers and ice sheets to changes in climate and thus <span class="hlt">sea</span> <span class="hlt">level</span>. Another fundamental problem has to do with incomplete knowledge of glacier areas and volumes, needed for analyses of <span class="hlt">sea-level</span> change due to changing climate. The authors proposed to develop an improved ability to predict the future contributions of glaciers to <span class="hlt">sea</span> <span class="hlt">level</span> by combining work from four research areas: remote sensing observations of calving activity and iceberg flux, numerical modeling of glacier dynamics, theoretical analysis of the calving process, and numerical techniques for modeling flow with large deformations and fracture. These four areas have never been combined into a single research effort on this subject; in particular, calving dynamics have never before been included explicitly in a model of glacier dynamics. A crucial issue that they proposed to address was the general question of how calving dynamics and glacier flow dynamics interact.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6119945','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6119945"><span>A Mid-Holocene <span class="hlt">sea</span> <span class="hlt">level</span> fluctuation in South Carolina</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gayes, P.T.; Nelson, D.D. . Marine and Wetland Studies); Scott, D.B.; Collins, E. . Centre for Marine Geology)</p> <p>1993-03-01</p> <p>A high stand of relative <span class="hlt">sea</span> <span class="hlt">level</span> occurred at 4.2 ka in Murrells Inlet on the northern coast of South Carolina. The event was identified using benthic foraminiferal zonations, marsh stratigraphic relations and radiocarbon data. This highstand reached a maximum of approximately [minus]1 meter MSD and was followed by a fall of 2 meters until 3.6 ka. Subsequent to 3.6 ka submergence was slow averaging 10 cm/century to the present. A second smaller fluctuation may have occurred around 2.5 ka but remains poorly constrained. Although a Mid-Holocene highstand had been suggested by others, it has not been well constrained. New data from North Inlet, South Carolina also record a baselevel change in the Mid-Holocene. Strong differential submergence between Murrells Inlet and Santee Delta, South Carolina, has occurred over the last 4 ka, probably as a result of sediment loading by and subsidence of, the Santee Delta. The occurrence of the 4.2 ka highstand corresponds in the range (7 [minus] 4 ka) to that of the Holocene Hypsithermal. The rate and magnitude of the relative <span class="hlt">sea</span> <span class="hlt">level</span> fluctuation are similar to those projected for future flooding and suggest that the evaluation of the Hypsithermal highstand may provide an insight to continued <span class="hlt">sea-level</span> rise.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730009903','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730009903"><span>Objective <span class="hlt">sea</span> <span class="hlt">level</span> pressure analysis for sparse data areas</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Druyan, L. M.</p> <p>1972-01-01</p> <p>A computer procedure was used to analyze the pressure distribution over the North Pacific Ocean for eleven synoptic times in February, 1967. Independent knowledge of the central pressures of lows is shown to reduce the analysis errors for very sparse data coverage. The application of planned remote sensing of <span class="hlt">sea-level</span> wind speeds is shown to make a significant contribution to the quality of the analysis especially in the high gradient mid-latitudes and for sparse coverage of conventional observations (such as over Southern Hemisphere oceans). Uniform distribution of the available observations of <span class="hlt">sea-level</span> pressure and wind velocity yields results far superior to those derived from a random distribution. A generalization of the results indicates that the average lower limit for analysis errors is between 2 and 2.5 mb based on the perfect specification of the magnitude of the <span class="hlt">sea-level</span> pressure gradient from a known verification analysis. A less than perfect specification will derive from wind-pressure relationships applied to satellite observed wind speeds.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70098419','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70098419"><span>How mangrove forests adjust to rising <span class="hlt">sea</span> <span class="hlt">level</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Krauss, Ken W.; McKee, Karen L.; Lovelock, Catherine E.; Cahoon, Donald R.; Saintilan, Neil; Reef, Ruth; Chen, Luzhen</p> <p>2014-01-01</p> <p>Mangroves are among the most well described and widely studied wetland communities in the world. The greatest threats to mangrove persistence are deforestation and other anthropogenic disturbances that can compromise habitat stability and resilience to <span class="hlt">sea-level</span> rise. To persist, mangrove ecosystems must adjust to rising <span class="hlt">sea</span> <span class="hlt">level</span> by building vertically or become submerged. Mangroves may directly or indirectly influence soil accretion processes through the production and accumulation of organic matter, as well as the trapping and retention of mineral sediment. In this review, we provide a general overview of research on mangrove elevation dynamics, emphasizing the role of the vegetation in maintaining soil surface elevations (i.e. position of the soil surface in the vertical plane). We summarize the primary ways in which mangroves may influence sediment accretion and vertical land development, for example, through root contributions to soil volume and upward expansion of the soil surface. We also examine how hydrological, geomorphological and climatic processes may interact with plant processes to influence mangrove capacity to keep pace with rising <span class="hlt">sea</span> <span class="hlt">level</span>. We draw on a variety of studies to describe the important, and often under-appreciated, role that plants play in shaping the trajectory of an ecosystem undergoing change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70148342','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70148342"><span><span class="hlt">Sea</span> <span class="hlt">level</span>, paleogeography, and archeology on California's Northern Channel Islands</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Reeder-Myers, Leslie; Erlandson, Jon M.; Muhs, Daniel R.; Rick, Torben C.</p> <p>2015-01-01</p> <p><span class="hlt">Sea-level</span> rise during the late Pleistocene and early Holocene inundated nearshore areas in many parts of the world, producing drastic changes in local ecosystems and obscuring significant portions of the archeological record. Although global forces are at play, the effects of <span class="hlt">sea-level</span> rise are highly localized due to variability in glacial isostatic adjustment (GIA) effects. Interpretations of coastal paleoecology and archeology require reliable estimates of ancient shorelines that account for GIA effects. Here we build on previous models for California's Northern Channel Islands, producing more accurate late Pleistocene and Holocene paleogeographic reconstructions adjusted for regional GIA variability. This region has contributed significantly to our understanding of early New World coastal foragers. <span class="hlt">Sea</span> <span class="hlt">level</span> that was about 80–85 m lower than present at the time of the first known human occupation brought about a landscape and ecology substantially different than today. During the late Pleistocene, large tracts of coastal lowlands were exposed, while a colder, wetter climate and fluctuating marine conditions interacted with rapidly evolving littoral environments. At the close of the Pleistocene and start of the Holocene, people in coastal California faced shrinking land, intertidal, and subtidal zones, with important implications for resource availability and distribution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70156427','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70156427"><span>Mangrove sedimentation and response to relative <span class="hlt">sea-level</span> rise</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Woodroffe, CD; Rogers, K.; Mckee, Karen L.; Lovelock, CE; Mendelssohn, IA; Saintilan, N.</p> <p>2016-01-01</p> <p>Mangroves occur on upper intertidal shorelines in the tropics and subtropics. Complex hydrodynamic and salinity conditions influence mangrove distributions, primarily related to elevation and hydroperiod; this review considers how these adjust through time. Accumulation rates of allochthonous and autochthonous sediment, both inorganic and organic, vary between and within different settings. Abundant terrigenous sediment can form dynamic mudbanks; tides redistribute sediment, contrasting with mangrove peat in sediment-starved carbonate settings. Sediments underlying mangroves sequester carbon, but also contain paleoenvironmental records of adjustments to past <span class="hlt">sea-level</span> changes. Radiometric dating indicates long-term sedimentation, whereas Surface Elevation Table-Marker Horizon measurements (SET-MH) provide shorter perspectives, indicating shallow subsurface processes of root growth and substrate autocompaction. Many tropical deltas also experience deep subsidence, which augments relative <span class="hlt">sea-level</span> rise. The persistence of mangroves implies an ability to cope with moderately high rates of relative <span class="hlt">sea-level</span> rise. However, many human pressures threaten mangroves, resulting in continuing decline in their extent throughout the tropics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5028851','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5028851"><span><span class="hlt">Sea</span> <span class="hlt">level</span> rise in Louisiana and Gulf of Mexico</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ramsey, K.; Penland, S. )</p> <p>1989-09-01</p> <p>Data from two tide-gage networks in Louisiana and the northern Gulf of Mexico were analyzed to determine local and regional trends in relative <span class="hlt">sea</span> <span class="hlt">level</span> rise. The US Army Corps of Engineers (USACE) maintains a network of 83 tide-gage stations throughout coastal Louisiana. Of these, 20 have records for two lunar nodal cycles or more, and some date back to 1933. The authors used the USACE data set to determine the local and regional character of relative <span class="hlt">sea</span> <span class="hlt">level</span> rise in Louisiana. The National ocean Survey (NOS) maintains nine tide gage stations throughout the northern Gulf of Mexico in Texas, Louisiana, Mississippi, Alabama, and Florida. All of the records of these stations exceed two lunar nodal cycles, and some date back to 1908. The authors used the NOS data set to determine the character of relative <span class="hlt">sea</span> <span class="hlt">level</span> rise throughout the northern Gulf of Mexico. This investigation updates and extends the previous systematic regional tide gage analysis (which covered 1908-1983) to 1988.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26407146','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26407146"><span>Mangrove Sedimentation and Response to Relative <span class="hlt">Sea-Level</span> Rise.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Woodroffe, C D; Rogers, K; McKee, K L; Lovelock, C E; Mendelssohn, I A; Saintilan, N</p> <p>2016-01-01</p> <p>Mangroves occur on upper intertidal shorelines in the tropics and subtropics. Complex hydrodynamic and salinity conditions, related primarily to elevation and hydroperiod, influence mangrove distributions; this review considers how these distributions change over time. Accumulation rates of allochthonous and autochthonous sediment, both inorganic and organic, vary between and within different settings. Abundant terrigenous sediment can form dynamic mudbanks, and tides redistribute sediment, contrasting with mangrove peat in sediment-starved carbonate settings. Sediments underlying mangroves sequester carbon but also contain paleoenvironmental records of adjustments to past <span class="hlt">sea-level</span> changes. Radiometric dating indicates long-term sedimentation, whereas measurements made using surface elevation tables and marker horizons provide shorter perspectives, indicating shallow subsurface processes of root growth and substrate autocompaction. Many tropical deltas also experience deep subsidence, which augments relative <span class="hlt">sea-level</span> rise. The persistence of mangroves implies an ability to cope with moderately high rates of relative <span class="hlt">sea-level</span> rise. However, many human pressures threaten mangroves, resulting in a continuing decline in their extent throughout the tropics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24251960','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24251960"><span>How mangrove forests adjust to rising <span class="hlt">sea</span> <span class="hlt">level</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Krauss, Ken W; McKee, Karen L; Lovelock, Catherine E; Cahoon, Donald R; Saintilan, Neil; Reef, Ruth; Chen, Luzhen</p> <p>2014-04-01</p> <p>Mangroves are among the most well described and widely studied wetland communities in the world. The greatest threats to mangrove persistence are deforestation and other anthropogenic disturbances that can compromise habitat stability and resilience to <span class="hlt">sea-level</span> rise. To persist, mangrove ecosystems must adjust to rising <span class="hlt">sea</span> <span class="hlt">level</span> by building vertically or become submerged. Mangroves may directly or indirectly influence soil accretion processes through the production and accumulation of organic matter, as well as the trapping and retention of mineral sediment. In this review, we provide a general overview of research on mangrove elevation dynamics, emphasizing the role of the vegetation in maintaining soil surface elevations (i.e. position of the soil surface in the vertical plane). We summarize the primary ways in which mangroves may influence sediment accretion and vertical land development, for example, through root contributions to soil volume and upward expansion of the soil surface. We also examine how hydrological, geomorphological and climatic processes may interact with plant processes to influence mangrove capacity to keep pace with rising <span class="hlt">sea</span> <span class="hlt">level</span>. We draw on a variety of studies to describe the important, and often under-appreciated, role that plants play in shaping the trajectory of an ecosystem undergoing change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ARMS....8..243W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ARMS....8..243W"><span>Mangrove Sedimentation and Response to Relative <span class="hlt">Sea-Level</span> Rise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Woodroffe, C. D.; Rogers, K.; McKee, K. L.; Lovelock, C. E.; Mendelssohn, I. A.; Saintilan, N.</p> <p>2016-01-01</p> <p>Mangroves occur on upper intertidal shorelines in the tropics and subtropics. Complex hydrodynamic and salinity conditions, related primarily to elevation and hydroperiod, influence mangrove distributions; this review considers how these distributions change over time. Accumulation rates of allochthonous and autochthonous sediment, both inorganic and organic, vary between and within different settings. Abundant terrigenous sediment can form dynamic mudbanks, and tides redistribute sediment, contrasting with mangrove peat in sediment-starved carbonate settings. Sediments underlying mangroves sequester carbon but also contain paleoenvironmental records of adjustments to past <span class="hlt">sea-level</span> changes. Radiometric dating indicates long-term sedimentation, whereas measurements made using surface elevation tables and marker horizons provide shorter perspectives, indicating shallow subsurface processes of root growth and substrate autocompaction. Many tropical deltas also experience deep subsidence, which augments relative <span class="hlt">sea-level</span> rise. The persistence of mangroves implies an ability to cope with moderately high rates of relative <span class="hlt">sea-level</span> rise. However, many human pressures threaten mangroves, resulting in a continuing decline in their extent throughout the tropics. *</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015QuRes..83..263R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015QuRes..83..263R"><span><span class="hlt">Sea</span> <span class="hlt">level</span>, paleogeography, and archeology on California's Northern Channel Islands</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Reeder-Myers, Leslie; Erlandson, Jon M.; Muhs, Daniel R.; Rick, Torben C.</p> <p>2015-03-01</p> <p><span class="hlt">Sea-level</span> rise during the late Pleistocene and early Holocene inundated nearshore areas in many parts of the world, producing drastic changes in local ecosystems and obscuring significant portions of the archeological record. Although global forces are at play, the effects of <span class="hlt">sea-level</span> rise are highly localized due to variability in glacial isostatic adjustment (GIA) effects. Interpretations of coastal paleoecology and archeology require reliable estimates of ancient shorelines that account for GIA effects. Here we build on previous models for California's Northern Channel Islands, producing more accurate late Pleistocene and Holocene paleogeographic reconstructions adjusted for regional GIA variability. This region has contributed significantly to our understanding of early New World coastal foragers. <span class="hlt">Sea</span> <span class="hlt">level</span> that was about 80-85 m lower than present at the time of the first known human occupation brought about a landscape and ecology substantially different than today. During the late Pleistocene, large tracts of coastal lowlands were exposed, while a colder, wetter climate and fluctuating marine conditions interacted with rapidly evolving littoral environments. At the close of the Pleistocene and start of the Holocene, people in coastal California faced shrinking land, intertidal, and subtidal zones, with important implications for resource availability and distribution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26587269','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26587269"><span>Nest inundation from <span class="hlt">sea-level</span> rise threatens <span class="hlt">sea</span> turtle population viability.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pike, David A; Roznik, Elizabeth A; Bell, Ian</p> <p>2015-07-01</p> <p>Contemporary <span class="hlt">sea-level</span> rise will inundate coastal habitats with seawater more frequently, disrupting the life cycles of terrestrial fauna well before permanent habitat loss occurs. <span class="hlt">Sea</span> turtles are reliant on low-lying coastal habitats worldwide for nesting, where eggs buried in the sand remain vulnerable to inundation until hatching. We show that saltwater inundation directly lowers the viability of green turtle eggs (Chelonia mydas) collected from the world's largest green turtle nesting rookery at Raine Island, Australia, which is undergoing enigmatic decline. Inundation for 1 or 3 h reduced egg viability by less than 10%, whereas inundation for 6 h reduced viability by approximately 30%. All embryonic developmental stages were vulnerable to mortality from saltwater inundation. Although the hatchlings that emerged from inundated eggs displayed normal physical and behavioural traits, hypoxia during incubation could influence other aspects of the physiology or behaviour of developing embryos, such as learning or spatial orientation. Saltwater inundation can directly lower hatching success, but it does not completely explain the consistently low rates of hatchling production observed on Raine Island. More frequent nest inundation associated with <span class="hlt">sea-level</span> rise will increase variability in <span class="hlt">sea</span> turtle hatching success spatially and temporally, due to direct and indirect impacts of saltwater inundation on developing embryos.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=PIA11002&hterms=Rising+sea+levels&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DRising%2Bsea%2Blevels','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=PIA11002&hterms=Rising+sea+levels&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DRising%2Bsea%2Blevels"><span>Portrait of a Warming Ocean and Rising <span class="hlt">Sea</span> <span class="hlt">Levels</span>: Trend of <span class="hlt">Sea</span> <span class="hlt">Level</span> Change 1993-2008</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2008-01-01</p> <p><p/> Warming water and melting land ice have raised global mean <span class="hlt">sea</span> <span class="hlt">level</span> 4.5 centimeters (1.7 inches) from 1993 to 2008. But the rise is by no means uniform. This image, created with <span class="hlt">sea</span> surface height data from the Topex/Poseidon and Jason-1 satellites, shows exactly where <span class="hlt">sea</span> <span class="hlt">level</span> has changed during this time and how quickly these changes have occurred. <p/> It's also a road map showing where the ocean currently stores the growing amount of heat it is absorbing from Earth's atmosphere and the heat it receives directly from the Sun. The warmer the water, the higher the <span class="hlt">sea</span> surface rises. The location of heat in the ocean and its movement around the globe play a pivotal role in Earth's climate. <p/> Light blue indicates areas in which <span class="hlt">sea</span> <span class="hlt">level</span> has remained relatively constant since 1993. White, red, and yellow are regions where <span class="hlt">sea</span> <span class="hlt">levels</span> have risen the most rapidly up to 10 millimeters per year and which contain the most heat. Green areas have also risen, but more moderately. Purple and dark blue show where <span class="hlt">sea</span> <span class="hlt">levels</span> have dropped, due to cooler water. <p/> The dramatic variation in <span class="hlt">sea</span> surface heights and heat content across the ocean are due to winds, currents and long-term changes in patterns of circulation. From 1993 to 2008, the largest area of rapidly rising <span class="hlt">sea</span> <span class="hlt">levels</span> and the greatest concentration of heat has been in the Pacific, which now shows the characteristics of the Pacific Decadal Oscillation (PDO), a feature that can last 10 to 20 years or even longer. <p/> In this 'cool' phase, the PDO appears as a horseshoe-shaped pattern of warm water in the Western Pacific reaching from the far north to the Southern Ocean enclosing a large wedge of cool water with low <span class="hlt">sea</span> surface heights in the eastern Pacific. This ocean/climate phenomenon may be caused by wind-driven Rossby waves. Thousands of kilometers long, these waves move from east to west on either side of the equator changing the distribution of water mass and heat. <p/> This image of <span class="hlt">sea</span> <span class="hlt">level</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2012/1025/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2012/1025/"><span>Preliminary investigation of the effects of <span class="hlt">sea-level</span> rise on groundwater <span class="hlt">levels</span> in New Haven, Connecticut</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Bjerklie, David M.; Mullaney, John R.; Stone, Janet R.; Skinner, Brian J.; Ramlow, Matthew A.</p> <p>2012-01-01</p> <p>Global <span class="hlt">sea</span> <span class="hlt">level</span> rose about 0.56 feet (ft) (170 millimeters (mm)) during the 20th century. Since the 1960s, <span class="hlt">sea</span> <span class="hlt">level</span> has risen at Bridgeport, Connecticut, about 0.38 ft (115 mm), at a rate of 0.008 ft (2.56 mm + or - 0.58 mm) per year. With regional subsidence, and with predicted global climate change, <span class="hlt">sea</span> <span class="hlt">level</span> is expected to continue to rise along the northeast coast of the United States through the 21st century. Increasing <span class="hlt">sea</span> <span class="hlt">levels</span> will cause groundwater <span class="hlt">levels</span> in coastal areas to rise in order to adjust to the new conditions. Some regional climate models predict wetter climate in the northeastern United States under some scenarios. Scenarios for the resulting higher groundwater <span class="hlt">levels</span> have the potential to inundate underground infrastructure in lowlying coastal cities. New Haven is a coastal city in Connecticut surrounded and bisected by tidally <span class="hlt">affected</span> waters. Monitoring of water <span class="hlt">levels</span> in wells in New Haven from August 2009 to July 2010 indicates the complex effects of urban influence on groundwater <span class="hlt">levels</span>. The response of groundwater <span class="hlt">levels</span> to recharge and season varied considerably from well to well. Groundwater temperatures varied seasonally, but were warmer than what was typical for Connecticut, and they seem to reflect the influence of the urban setting, including the effects of conduits for underground utilities. Specific conductance was elevated in many of the wells, indicating the influence of urban activities or seawater in Long Island Sound. A preliminary steady-state model of groundwater flow for part of New Haven was constructed using MODFLOW to simulate current groundwater <span class="hlt">levels</span> (2009-2010) and future groundwater <span class="hlt">levels</span> based on scenarios with a rise of 3 ft (0.91 meters (m)) in <span class="hlt">sea</span> <span class="hlt">level</span>, which is predicted for the end of the 21st century. An additional simulation was run assuming a 3-ft rise in <span class="hlt">sea</span> <span class="hlt">level</span> combined with a 12-percent increase in groundwater recharge. The model was constructed from existing hydrogeologic information for the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70031023','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70031023"><span>Holocene <span class="hlt">sea</span> <span class="hlt">level</span> and climate change in the Black <span class="hlt">Sea</span>: Multiple marine incursions related to freshwater discharge events</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Martin, R.E.; Leorri, E.; McLaughlin, P.P.</p> <p>2007-01-01</p> <p>Repeated marine invasions of the Black <span class="hlt">Sea</span> during the Holocene have been inferred by many eastern scientists as resulting from episodes of marine inflow from the Mediterranean beneath a brackish outflow from the Black <span class="hlt">Sea</span>. We support this scenario but a fundamental question remains: What caused the repeated marine invasions? We offer an hypothesis for the repeated marine invasions of the Black <span class="hlt">Sea</span> based on: (1) the overall similarity of <span class="hlt">sea-level</span> curves from both tectonically quiescent and active margins of the Black <span class="hlt">Sea</span> and their similarity to a sequence stratigraphic record from the US mid-Atlantic coast. The similarity of the records from two widely-separated regions suggests their common response to documented Holocene climate ocean-atmosphere reorganizations (coolings); (2) the fact that in the modern Black <span class="hlt">Sea</span>, freshwater runoff from surrounding rivers dominates over evaporation, so that excess runoff might have temporarily raised Black <span class="hlt">Sea</span> <span class="hlt">level</span> (although the Black <span class="hlt">Sea</span> would have remained brackish). Following the initial invasion of the Black <span class="hlt">Sea</span> by marine Mediterranean waters (through the Marmara <span class="hlt">Sea</span>) in the early Holocene, repeated marine incursions were modulated, or perhaps even caused, by freshwater discharge to the Black <span class="hlt">Sea</span>. Climatic amelioration (warming) following each documented ocean-atmosphere reorganization during the Holocene likely shifted precipitation patterns in the surrounding region and caused mountain glaciers to retreat, increasing freshwater runoff above modern values and temporarily contributing to an increase of Black <span class="hlt">Sea</span> <span class="hlt">level</span>. Freshwater-to-brackish water discharges into the Black <span class="hlt">Sea</span> initially slowed marine inflow but upon mixing of runoff with more marine waters beneath them and their eventual exit through the Bosphorus, marine inflow increased again, accounting for the repeated marine invasions. The magnitude of the hydrologic and <span class="hlt">sea-level</span> fluctuations became increasingly attenuated through the Holocene, as reflected by Black</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EOSTr..94..283U','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EOSTr..94..283U"><span>The Science and Communication Needed to Help Communities Plan for <span class="hlt">Sea</span> <span class="hlt">Level</span> Rise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Uhlenbrock, Kristan</p> <p>2013-08-01</p> <p>From the shores of Bangladesh to the bayous of Louisiana, <span class="hlt">sea</span> <span class="hlt">level</span> rise will <span class="hlt">affect</span> communities across the globe and will likely be exacerbated by other threats such as severe weather. Local and national decision makers face a myriad of challenges as they prepare for or adapt to changing coastal conditions while trying to manage increasing population and development along the coasts. In the United States alone, approximately 39% of the population lives in a coastal county.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMPP53B2002C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMPP53B2002C"><span>Late Holocene <span class="hlt">Sea-Level</span> Changes in French Polynesia, South-Central Pacific</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Camoin, G.; Hallmann, N.; Eisenhauer, A.; Samankassou, E.; Milne, G. A.</p> <p>2013-12-01</p> <p>Camoin, G.1, Hallmann, N.1, Eisenhauer, A.2, Vella, C.1, Samankassou, E.3, Fietzke, J.2, Milne, G.A.4 1 Aix-Marseille Université, CNRS, IRD, CEREGE UM34, Europôle Méditerranéen de l'Arbois, BP80, 13545 Aix-en-Provence cedex 4, France 2 Helmholtz-Zentrum für Ozeanforschung GEOMAR, Kiel, Wischhofstrasse 1-3, 24148 Kiel, Germany 3 University of Geneva, Rue des Maraîchers 13, CH-1205 Geneva, Switzerland 4 University of Ottawa, Department of Earth Sciences, Ottawa, Ontario, K1N 6N5, Canada Knowledge of the timing and course of <span class="hlt">sea-level</span> changes provides an essential framework for conceptual models aimed at understanding the dynamics of melting of large ice sheets and their effects on the isostasy of the Earth. The marked variability of local Holocene <span class="hlt">sea</span> <span class="hlt">levels</span>, responding both to ice-sheet unloading and the redistribution of water masses in the global ocean, demonstrates the need to constrain geophysical processes that include hydro-isostasy, equatorial ocean syphoning and tectonic movements <span class="hlt">affecting</span> relative <span class="hlt">sea-level</span> positions. A regional reconstruction of Late Holocene <span class="hlt">sea-level</span> changes (i.e., the last 6,000 yrs) in French Polynesia is based on the accurate U-series dating of in situ <span class="hlt">sea-level</span> indicators (coral colonies including microatolls; bivalves) and their precise vertical and horizontal GPS positioning in five atolls (Fakarava, Hao, Manihi, Rangiroa, Tikehau) from the Tuamotu Archipelago and six high islands (Bora Bora, Mangareva, Maupiti, Moorea, Raivavae, Rurutu) from the Society, Gambier and Austral Archipelagos. These islands provide the opportunity to reconstruct accurately Late Holocene <span class="hlt">sea-level</span> changes that are well-suited to estimate eustatic and isostatic changes because : 1) they exhibit unique coral reef records including valuable <span class="hlt">sea-level</span> indicators, such as corals and bivalves in growth position, emerged coral conglomerates and beachrocks, 2) their subsidence rates are negligible for the Late Holocene period, thus excluding any tectonic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMNH23C..07G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMNH23C..07G"><span>Incorporating Tsunami Projections to <span class="hlt">Sea</span> <span class="hlt">Level</span> Rise Vulnerability Assessments -A Case Study for Midway Atoll-</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gica, E.; Reynolds, M.</p> <p>2012-12-01</p> <p>Recent global models predict a rise of approximately one meter in global <span class="hlt">sea</span> <span class="hlt">level</span> by 2100, with potentially larger increases in areas of the Pacific Ocean. If current climate change trends continue, low-lying islands across the globe may become inundated over the next century, placing island biodiversity at risk. Adding to the risk of inundation due to <span class="hlt">sea</span> <span class="hlt">level</span> rise is the occurrence of cyclones and tsunamis. This combined trend will <span class="hlt">affect</span> the low-lying islands of the Northwestern Hawaiian Islands and it is therefore important to assess its impact since these islands are critical habitats to many endangered endemic species and support the largest tropical seabird rookery in the world. The 11 March 2011 Tohoku (Mw=8.8) earthquake-tsunami <span class="hlt">affected</span> the habitat of many endangered endemic species in Midway Atoll National Wildlife Refuge because all three islands (Sand, Eastern and Spit) were inundated by tsunami waves. At present <span class="hlt">sea</span> <span class="hlt">level</span>, some tsunamis from certain source regions would not <span class="hlt">affect</span> Midway Atoll. For example, the previous earthquake-tsunamis such as the 15 November 2006 Kuril (Mw=8.1) and 13 February 2007 Kuril (Mw=7.9) were not significant enough to <span class="hlt">affect</span> Midway Atoll. But at higher <span class="hlt">sea</span> <span class="hlt">levels</span>, tsunamis with similar characteristics could pose a threat to such terrestrial habitats and wildlife. To visualize projected impacts to vegetation composition, wildlife habitat, and wildlife populations, we explored and analyzed inundation vulnerability for a range of possible <span class="hlt">sea</span> <span class="hlt">level</span> rise and tsunami scenarios at Midway Atoll National Wildlife Refuge. Studying the combined threat of tsunamis and <span class="hlt">sea</span> <span class="hlt">level</span> rise can provide more accurate and comprehensive assessments of the vulnerability of the unique natural resources on low-lying islands. A passive <span class="hlt">sea</span> <span class="hlt">level</span> rise model was used to determine how much inundation will occur at different <span class="hlt">sea</span> <span class="hlt">level</span> rise values for the three islands of Midway Atoll and each scenario was coupled with NOAA Center for Tsunami</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008PhDT.......110R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008PhDT.......110R"><span>Modeling future <span class="hlt">sea</span> <span class="hlt">level</span> rise from melting glaciers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Radic, Valentina</p> <p></p> <p>Melting mountain glaciers and ice caps (MG&IC) are the second largest contributor to rising <span class="hlt">sea</span> <span class="hlt">level</span> after thermal expansion of the oceans and are likely to remain the dominant glaciological contributor to rising <span class="hlt">sea</span> <span class="hlt">level</span> in the 21st century. The aim of this work is to project 21st century volume changes of all MG&IC and to provide systematic analysis of uncertainties originating from different sources in the calculation. I provide an ensemble of 21st century volume projections for all MG&IC from the World Glacier Inventory by modeling the surface mass balance coupled with volume-area-length scaling and forced with temperature and precipitation scenarios from four Global Climate Models (GCMs). By upscaling the volume projections through a regionally differentiated approach to all MG&IC outside Greenland and Antarctica (514,380 km 2) I estimated total volume loss for the time period 2001-2100 to range from 0.039 to 0.150 m <span class="hlt">sea</span> <span class="hlt">level</span> equivalent. While three GCMs agree that Alaskan glaciers are the main contributors to the projected <span class="hlt">sea</span> <span class="hlt">level</span> rise, one GCM projected the largest total volume loss mainly due to Arctic MG&IC. The uncertainties in the projections are addressed by a series of sensitivity tests applied in the methodology for assessment of global volume changes and on individual case studies for particular glaciers. Special emphasis is put on the uncertainties in volume-area scaling. For both, individual and global assessments of volume changes, the choice of GCM forcing glacier models is shown to be the largest source of quantified uncertainties in the projections. Another major source of uncertainty is the temperature forcing in the mass balance model depending on the quality of climate reanalysis products (ERA-40) in order to simulate the local temperatures on a mountain glacier or ice cap. Other uncertainties in the methods are associated with volume-area-length scaling as a tool for deriving glacier initial volumes and glacier geometry changes in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5808621','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5808621"><span>Climate-induced variations in lake <span class="hlt">levels</span>: A mechanism for short-term <span class="hlt">sea</span> <span class="hlt">level</span> change during non-glacial times</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Jacobs, D. ); Sahagian, D. . Dept of Geological Sciences)</p> <p>1992-01-01</p> <p>Variations in insolation due to periodic orbital parameters can cause climatic changes and associated variations in the intensity of monsoonal circulation. This can lead to significant variations in the <span class="hlt">levels</span> of internally draining lakes on timescales of 10,000 to 100,000 years in regions <span class="hlt">affected</span> by the monsoon (20,000 years for orbital precession). These variations may be responsible for small scale (few meters) eustatic <span class="hlt">sea</span> <span class="hlt">level</span> changes in an ice-free Earth, and may contribute to <span class="hlt">sea</span> <span class="hlt">level</span> changes in the presence of ice as well. The authors have estimated the volume of empty present lake basins in the regions of Asia and North Africa influenced by the monsoon. The surface water volume alone of these basins is equivalent to a two meter difference in <span class="hlt">sea</span> <span class="hlt">level</span>, but is considerably augmented by groundwater associated with an increase in lake <span class="hlt">level</span>. The lake variation mechanism for <span class="hlt">sea</span> <span class="hlt">level</span> change has its basis in the Quaternary record of climate change and associated explanatory models. However, the argument also applies to earlier, non-glacial periods of geologic time. Clear evidence for the presence of ice in the Triassic is lacking. However, there is evidence for short-term periodic fluctuations of lake <span class="hlt">levels</span> as well as <span class="hlt">sea</span> <span class="hlt">level</span> during that time. These <span class="hlt">sea</span> <span class="hlt">level</span> changes, as well as those in the Devonian, Jurassic, and Cretaceous, may be driven by periodic fluctuation in lacustrine and groundwater storage resulting from orbitally forced changes in monsoon intensity, even in the absence of significant glacial ice.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70031475','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70031475"><span>Modeling barrier island response to <span class="hlt">sea-level</span> rise in the outer Banks, North Carolina</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Moore, Laura J.; List, Jeffrey H.; Williams, S. Jeffress; Stolper, David</p> <p>2007-01-01</p> <p>An 8500-year Holocene simulation developed in GEOMBEST provides a possible scenario to explain the evolution of barrier coast between Rodanthe and Cape Hatteras, NC. Sensitivity analyses suggest that in the Outer Banks, the rate of <span class="hlt">sea-level</span> rise is the most important factor in determining how barrier islands evolve. The Holocene simulation provides a basis for future simulations, which suggest that if <span class="hlt">sea</span> <span class="hlt">level</span> rises up to 0.88 m by AD 2100, as predicted by the highest estimates of the Intergovernmental Panel on Climate Change, the barrier in the study area may migrate on the order of 2.5 times more rapidly than at present. If <span class="hlt">sea</span> <span class="hlt">level</span> rises beyond IPCC predictions to reach 1.4–1.9 m above modern <span class="hlt">sea</span> <span class="hlt">level</span> by AD 2100, model results suggest that barrier islands in the Outer Banks may become vulnerable to threshold collapse, disintegrating during storm events, by the end of the next century. Consistent with sensitivity analyses, additional simulations indicate that anthropogenic activities, such as increasing the rate of sediment supply through beach nourishment, will only slightly <span class="hlt">affect</span> barrier island migration rates and barrier island vulnerability to collapse.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMNH23C..03D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMNH23C..03D"><span><span class="hlt">Sea-Level</span> Rise for California, Oregon, and Washington: Present and Future</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dalrymple, R. A.</p> <p>2012-12-01</p> <p>This talk discusses the results of a NRC study on U.S. west coast <span class="hlt">sea-level</span> rise, completed in June. The first part of the study deals with global <span class="hlt">sea</span> <span class="hlt">level</span> rise, utilizing data generated since the IPCC (2007) report and examining each of the major contributors to <span class="hlt">sea-level</span> risel: thermal expansion of <span class="hlt">sea</span> water in response to a warming atmosphere and ice melt from glaciers, ice caps, and ice sheets. Results show that land ice melt is currently the largest contributor to <span class="hlt">sea</span> <span class="hlt">level</span> rise. Predictions of global <span class="hlt">sea</span> <span class="hlt">level</span> are developed for 2030, 2050, and 2100. Next, regional <span class="hlt">sea</span> <span class="hlt">level</span> is determined by including the effects of local vertical land motions, from tectonics, subsidence, and the spatial distribution of ice melt <span class="hlt">sea</span> <span class="hlt">level</span> contributions (<span class="hlt">sea</span> <span class="hlt">level</span> fingerprinting). Of particular interest is the potential of a Cascadia subduction zone earthquake that could add more than a meter of <span class="hlt">sea-level</span> rise in minutes in addition to the expected <span class="hlt">sea</span> <span class="hlt">level</span> rise. Again, predictions of <span class="hlt">sea-level</span> rise for the shoreline of the west coast for 2030, 2050, and 2100 are determined. Implications of <span class="hlt">sea</span> <span class="hlt">level</span> rise on storminess, and the erosion of beaches, coastal cliffs, and wetlands are discussed as well.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.1599Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.1599Y"><span>Grain-size based <span class="hlt">sea-level</span> reconstruction in the south Bohai <span class="hlt">Sea</span> during the past 135 kyr</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yi, Liang; Chen, Yanping</p> <p>2013-04-01</p> <p>Future anthropogenic <span class="hlt">sea-level</span> rise and its impact on coastal regions is an important issue facing human civilizations. Due to the short nature of the instrumental record of <span class="hlt">sea-level</span> change, development of proxies for <span class="hlt">sea-level</span> change prior to the advent of instrumental records is essential to reconstruct long-term background <span class="hlt">sea-level</span> changes on local, regional and global scales. Two of the most widely used approaches for past <span class="hlt">sea-level</span> changes are: (1) exploitation of dated geomorphologic features such as coastal sands (e.g. Mauz and Hassler, 2000), salt marsh (e.g. Madsen et al., 2007), terraces (e.g. Chappell et al., 1996), and other coastal sediments (e.g. Zong et al., 2003); and (2) <span class="hlt">sea-level</span> transfer functions based on faunal assemblages such as testate amoebae (e.g. Charman et al., 2002), foraminifera (e.g. Chappell and Shackleton, 1986; Horton, 1997), and diatoms (e.g. Horton et al., 2006). While a variety of methods has been developed to reconstruct palaeo-changes in <span class="hlt">sea</span> <span class="hlt">level</span>, many regions, including the Bohai <span class="hlt">Sea</span>, China, still lack detailed relative <span class="hlt">sea-level</span> curves extending back to the Pleistocene (Yi et al., 2012). For example, coral terraces are absent in the Bohai <span class="hlt">Sea</span>, and the poor preservation of faunal assemblages makes development of a transfer function for a relative <span class="hlt">sea-level</span> reconstruction unfeasible. In contrast, frequent alternations between transgression and regression has presumably imprinted <span class="hlt">sea-level</span> change on the grain size distribution of Bohai <span class="hlt">Sea</span> sediments, which varies from medium silt to coarse sand during the late Quaternary (IOCAS, 1985). Advantages of grainsize-based relative <span class="hlt">sea-level</span> transfer function approaches are that they require smaller sample sizes, allowing for replication, faster measurement and higher spatial or temporal resolution at a fraction of the cost of detail micro-palaeontological analysis (Yi et al., 2012). Here, we employ numerical methods to partition sediment grain size using a combined database of</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70029895','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70029895"><span>Holocene <span class="hlt">sea-level</span> oscillations and environmental changes on the Eastern Black <span class="hlt">Sea</span> shelf</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Ivanova, E.V.; Murdmaa, I.O.; Chepalyga, A.L.; Cronin, T. M.; Pasechnik, I.V.; Levchenko, O.V.; Howe, S.S.; Manushkina, A.V.; Platonova, E.A.</p> <p>2007-01-01</p> <p>A multi-proxy study of four sediment cores from the Eastern (Caucasian) Black <span class="hlt">Sea</span> shelf revealed five transgressive-regressive cycles overprinted on the general trend of glacioeustatic <span class="hlt">sea-level</span> rise during the last 11,000??14C yr. These cycles are well represented in micro-and macrofossil assemblages, sedimentation rates, and grain size variations. The oldest recovered sediments were deposited in the Neoeuxinian semi-freshwater basin (??? 10,500-9000??14C yr BP) and contain a Caspian-type mollusk fauna dominated by Dreissena rostriformis. Low ??18O and ??13C values are measured on this species. The first appearance of marine mollusks and ostracodes from the Mediterranean is established in this part of the Black <span class="hlt">Sea</span> at ??? 8200??14C yr BP, i.e., about 1000-2000??yr later than the appearance of marine microfossils in the deeper part of the <span class="hlt">sea</span>. The Early Holocene (Bugazian to Vityazevian) condensed section of shell and shelly mud sediments with at least two hiatuses represent a high-energy shelf-edge facies. It contains a transitional assemblage representing a mixture of Caspian and Mediterranean fauna. This pattern suggests a dual-flow regime via the Bosphorus after 8200??14C yr BP. Caspian species disappear and oligohaline species decrease in abundance during the Vityazevian-Prekalamitian cycle. Later, during the Middle to Late Holocene, low <span class="hlt">sea-level</span> stands are characterized by shell layers, whereas silty mud with various mollusk and ostracode assemblages rapidly accumulated during transgressions. Restricted mud accumulation, as well as benthic faunal composition and abundance, suggest high-energy and well-ventilated bottom water during low <span class="hlt">sea-level</span> stands. A trend of 18O enrichment in mollusk shells points to an increase in bottom-water salinity during the Vityazevian to Kalamitian transgressions (??? 7000 to 5700??14C yr BP) due to a more open connection with the Mediterranean, while a pronounced increase in polyhaline species abundance is established during</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6645326','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6645326"><span>Correlation of <span class="hlt">sea</span> <span class="hlt">level</span> falls interpreted from atoll stratigraphy with turbidites in adjacent basins</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lincoln, J.M. )</p> <p>1990-05-01</p> <p>Past <span class="hlt">sea</span> <span class="hlt">levels</span> can be derived from any atoll subsurface sediments deposited at or near <span class="hlt">sea</span> <span class="hlt">level</span> by determining the ages of deposition and correcting the present depths to the sediments for subsidence of the underlying edifice since the times of deposition. A <span class="hlt">sea</span> <span class="hlt">level</span> curve constructed by this method consists of discontinuous segments, each corresponding to a period of rising relative <span class="hlt">sea</span> <span class="hlt">level</span> and deposition of a discrete sedimentary package. Discontinuities in the <span class="hlt">sea</span> <span class="hlt">level</span> curve derived by this method correspond to relative <span class="hlt">sea</span> <span class="hlt">level</span> falls and stratigraphic hiatuses in the atoll subsurface. During intervals of relative <span class="hlt">sea</span> <span class="hlt">level</span> fall an atoll emerges to become a high limestone island. <span class="hlt">Sea</span> <span class="hlt">level</span> may fluctuate several times during a period of atoll emergence to become a high limestone island. <span class="hlt">Sea</span> <span class="hlt">level</span> may fluctuate several times during a period of atoll emergence without depositing sediments on top of the atoll. Furthermore, subaerial erosion may remove a substantial part of the depositional record of previous <span class="hlt">sea</span> <span class="hlt">level</span> fluctuations. For these reasons the authors must look to the adjacent basins to complement the incomplete record of <span class="hlt">sea</span> <span class="hlt">level</span> change recorded beneath atolls. During lowstands of <span class="hlt">sea</span> <span class="hlt">level</span>, faunas originally deposited near <span class="hlt">sea</span> <span class="hlt">level</span> on an atoll may be eroded and redeposited as turbidites in deep adjacent basins. Three such turbidites penetrated during deep-<span class="hlt">sea</span> drilling at Sites 462 and 315 in the central Pacific correlate well with a late Tertiary <span class="hlt">sea</span> <span class="hlt">level</span> curve based on biostratigraphic ages and {sup 87}Sr/{sup 86}Sr chronostratigraphy for core from Enewetak Atoll in the northern Marshall Islands. Further drilling of the archipelagic aprons adjacent to atolls will improve the <span class="hlt">sea</span> <span class="hlt">level</span> history that may be inferred from atoll stratigraphy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7043S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7043S"><span><span class="hlt">Sea</span> <span class="hlt">level</span> rise of semi-enclosed basins: deviation of Adriatic and Baltic <span class="hlt">sea</span> <span class="hlt">level</span> from the mean global value.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Scarascia, Luca; Lionello, Piero</p> <p>2015-04-01</p> <p>Future <span class="hlt">sea</span> <span class="hlt">level</span> rise (SL), which represents today one of the major threats that are caused by climate change, will not be uniform. Regional differences are crucial for 40% of the world population, which is located in the coastal zone. To explore the mechanisms linking regional SL to climate variables is very important in order to provide reliable future projections. This study focuses on two semi-enclosed basins, the Adriatic and Baltic <span class="hlt">Sea</span> and investigates the deviation of their SL from the mean global value. In fact, past deviations of the SL of these two basins from the global value have been observed and can be attributed to large scale factors (such as teleconnections) and regional factors, such as the inverse barometric effect, the wind stress, the thermosteric and halosteric effects. The final goal of this work is to assess to which extent the Adriatic and Baltic SL will depart from the mean global value in the next decades and at the end of 21st century. This is achieved by analyzing deviations of the mean SL of the Baltic and Adriatic <span class="hlt">Sea</span> from the global mean SL during the 20th century and investigating which factors can explain such deviations. A multivariate linear regression model is built and used to describe the link between three large scale climate variables which are used as predictors (mean <span class="hlt">sea</span> <span class="hlt">level</span> pressure, surface air temperature and precipitation), and the regional SL deviation (the predictand), computed as the difference between the regional and the global SL. At monthly scale this linear regression model provides a good reconstruction of the past variability in the cold season during which it explains 60%-70% of the variance. Summer reconstruction is substantially less successful and it represents presently the main limit of the model skill. This linear regression model, forced by predictors extracted from CMIP5 multi-model simulations, is used to provide projections of SL in the Adriatic and Baltic <span class="hlt">Sea</span>. On the basis of the projections</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1813447B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1813447B"><span>Observational uncertainty of Arctic <span class="hlt">sea</span>-ice concentration significantly <span class="hlt">affects</span> seasonal climate forecasts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bunzel, Felix; Notz, Dirk; Baehr, Johanna; Müller, Wolfgang; Fröhlich, Kristina</p> <p>2016-04-01</p> <p>We examine how the choice of a particular satellite-retrieved <span class="hlt">sea</span>-ice concentration dataset used for initialising seasonal climate forecasts impacts the prediction skill of Arctic <span class="hlt">sea</span>-ice area and Northern hemispheric 2-meter air temperatures. To do so, we performed two assimilation runs with the Max Planck Institute Earth System Model (MPI-ESM) from 1979 to 2012, where atmospheric and oceanic parameters as well as <span class="hlt">sea</span>-ice concentration were assimilated using Newtonian relaxation. The two assimilation runs differ only in the <span class="hlt">sea</span>-ice concentration dataset used for assimilating <span class="hlt">sea</span> ice. In the first run, we use <span class="hlt">sea</span>-ice concentrations as derived by the NASA-Team algorithm, while in the second run we use <span class="hlt">sea</span>-ice concentrations as derived from the Bootstrap algorithm. A major difference between these two <span class="hlt">sea</span>-ice concentration data products involves the treatment of melt ponds. While for both products melt ponds appear as open water in the raw satellite data, the Bootstrap algorithm more strongly attempts to offset this systematic bias by synthetically increasing the retrieved ice concentration during summer months. For each year of the two assimilation runs we performed a 10-member ensemble of hindcast experiments starting on 1 May and 1 November with a hindcast length of 6 months. For hindcasts started in November, initial differences in Arctic <span class="hlt">sea</span>-ice area and surface temperature decrease rapidly throughout the freezing period. For hindcasts started in May, initial <span class="hlt">sea</span>-ice area differences increase over time. By the end of the melting period, this causes significant differences in 2-meter air temperature of regionally more than 3°C. Hindcast skill for surface temperatures over Europe and North America is higher with Bootstrap initialization during summer and with NASA Team initialisation during winter. This implies that the choice of the <span class="hlt">sea</span>-ice data product and, thus, the observational uncertainty also <span class="hlt">affects</span> forecasts of teleconnections that depend on Northern</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMOS23C..07S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMOS23C..07S"><span><span class="hlt">Sea-Level</span> Acceleration Hotspot along the Atlantic Coast of North America</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sallenger, A. H.; Doran, K. J.; Howd, P.</p> <p>2012-12-01</p> <p>Spatial variations of <span class="hlt">sea</span> <span class="hlt">level</span> rise (SLR) can be forced by dynamic processes arising from circulation and variations in temperature and/or salinity, and by static equilibrium processes arising from mass re-distributions changing gravity and the earth's rotation and shape. The <span class="hlt">sea-level</span> variations can form unique spatial patterns, yet there are very few field observations verifying predicted patterns, or fingerprints. We present evidence of SLR acceleration in a 1,000-km-long hotspot on the North American Atlantic coast north of Cape Hatteras, North Carolina to above Boston, Massachusetts. By using accelerations, or rate differences, <span class="hlt">sea</span> <span class="hlt">level</span> signals that are linear over sub-century records, like the relative <span class="hlt">sea</span> <span class="hlt">level</span> changes arising from vertical land movements of glacial isostatic adjustment, do not <span class="hlt">affect</span> our results. For a 60-yr regression window (between 1950-1979 and 1980-2009), mean increase in the rate of SLR in the hotspot was 1.97 ± 0.64 mm/yr. (For a 40-yr window, the mean rate increase was 3.80 ± 1.06 mm/yr.) South of Cape Hatteras to Key West, Florida, rate differences for either 60 yr or 40 yr windows were not statistically different from zero (e.g. for 60 yr window: mean= 0.11 ± 0.92 mm/yr). This pattern is similar to a fingerprint of dynamic SLR established by <span class="hlt">sea-level</span> projections in several climate model studies. Correlations were consistent with accelerated SLR associated with a slowdown of Atlantic Meridional Overturning Current.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009QSRv...28.1786J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009QSRv...28.1786J"><span>Conceptual framework for assessing the response of delta channel networks to Holocene <span class="hlt">sea</span> <span class="hlt">level</span> rise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jerolmack, Douglas J.</p> <p>2009-08-01</p> <p>Recent research has identified two fundamental unit processes that build delta distributary channels. The first is mouth-bar deposition at the shoreline and subsequent channel bifurcation, which is driven by progradation of the shoreline; the second is avulsion to a new channel, a result of aggradation of the delta topset. The former creates relatively small, branching networks such as Wax Lake Delta; the latter generates relatively few, long distributaries such as the Mississippi and Atchafalaya channels on the Mississippi Delta. The relative rate of progradation to aggradation, and hence the creation of accommodation space, emerges as a controlling parameter on channel network form. Field and experimental research has identified <span class="hlt">sea</span> <span class="hlt">level</span> as the dominant control on Holocene delta growth worldwide, and has empirically linked channel network changes to changes in the rate of <span class="hlt">sea</span> <span class="hlt">level</span> rise. Here I outline a simple modeling framework for distributary network evolution, and use this to explore large-scale changes in Holocene channel pattern that have been observed in deltas such as the Rhine-Meuse and Mississippi. Rapid early- to mid-Holocene <span class="hlt">sea</span> <span class="hlt">level</span> rise forced many deltas into an aggradational mode, where I hypothesize that avulsion and the generation of large-scale branches should dominate. Slowing of <span class="hlt">sea</span> <span class="hlt">level</span> rise in the last ˜6000 yr allowed partitioning of sediment into progradation, facilitating the growth of smaller-scale distributary trees at the shorelines of some deltas, and a reduction in the number of large-scale branches. Significant antecedent topography modulates delta response; the filling of large incised valleys, for example, caused many deltas to bypass the aggradational phase. Human effects on deltas can be cast in terms of geologic controls <span class="hlt">affecting</span> accommodation: constriction of channels forces rapid local progradation and mouth-bar bifurcation, while accelerated <span class="hlt">sea</span> <span class="hlt">level</span> rise increases aggradation and induces more frequent channel</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..1410078H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..1410078H"><span>The Semiannual Oscillation of Southern Ocean <span class="hlt">Sea</span> <span class="hlt">Level</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hibbert, A.</p> <p>2012-04-01</p> <p>The atmospheric Semiannual Oscillation (SAO) is a half-yearly wave in mean <span class="hlt">sea</span> <span class="hlt">level</span> air pressure, which exhibits equinoctial maxima between 45°S and 50°S and solstitial maxima between 55°S and 65°s, with a phase reversal occurring at around 60°S. Its existence has been attributed to a phase difference in the annual temperature cycle between mid- and high-latitudes which sets up meridional temperature and pressure gradients that are largest during September and March, enhancing atmospheric baroclinicity and inducing equinoctial maxima in the Southern Hemisphere Westerlies. In this study, we use harmonic analysis of atmospheric and oceanic Southern Ocean datasets to show that this atmospheric SAO induces oceanic counterparts in <span class="hlt">sea</span> <span class="hlt">level</span> and circumpolar transport. This aspect of atmosphere-ocean interaction is particularly important, given the capacity of the Antarctic Circumpolar Current (ACC) to influence regional climate through the exchange of heat, fresh water and nutrients to each of the major ocean basins. We examine the relative contributions of local and regional semiannual atmospheric fluctuations in explaining the observed <span class="hlt">sea</span> <span class="hlt">level</span> response at 20 Southern Ocean and South Atlantic tide gauge stations and find that the oceanic SAO is associated with a modulation of zonal surface wind strength at key latitudes between ~55°S and 65°S. We also explore whether a seasonal inequality in SAO amplitude might facilitate the deduction of the timescales upon which Southern Ocean 'eddy saturation' theory might operate. However, though we find evidence of biannual fluctuations in eddy kinetic energy, regional variations in the phases and amplitudes of these emergent harmonics prevent us from elucidating the possible timescales upon which an eddy response to the atmospheric SAO might arise.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017QSRv..155...13K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017QSRv..155...13K"><span>Drivers of Holocene <span class="hlt">sea-level</span> change in the Caribbean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khan, Nicole S.; Ashe, Erica; Horton, Benjamin P.; Dutton, Andrea; Kopp, Robert E.; Brocard, Gilles; Engelhart, Simon E.; Hill, David F.; Peltier, W. R.; Vane, Christopher H.; Scatena, Fred N.</p> <p>2017-01-01</p> <p>We present a Holocene relative <span class="hlt">sea-level</span> (RSL) database for the Caribbean region (5°N to 25°N and 55°W to 90°W) that consists of 499 <span class="hlt">sea-level</span> index points and 238 limiting dates. The database was compiled from multiple <span class="hlt">sea-level</span> indicators (mangrove peat, microbial mats, beach rock and acroporid and massive corals). We subdivided the database into 20 regions to investigate the influence of tectonics and glacial isostatic adjustment on RSL. We account for the local-scale processes of sediment compaction and tidal range change using the stratigraphic position (overburden thickness) of index points and paleotidal modeling, respectively. We use a spatio-temporal empirical hierarchical model to estimate RSL position and its rates of change in the Caribbean over 1-ka time slices. Because of meltwater input, the rates of RSL change were highest during the early Holocene, with a maximum of 10.9 ± 0.6 m/ka in Suriname and Guyana and minimum of 7.4 ± 0.7 m/ka in south Florida from 12 to 8 ka. Following complete deglaciation of the Laurentide Ice Sheet (LIS) by ∼7 ka, mid-to late-Holocene rates slowed to < 2.4 ± 0.4 m/ka. The hierarchical model constrains the spatial extent of the mid-Holocene highstand. RSL did not exceed the present height during the Holocene, except on the northern coast of South America, where in Suriname and Guyana, RSL attained a height higher than present by 6.6 ka (82% probability). The highstand reached a maximum elevation of +1.0 ± 1.1 m between 5.3 and 5.2 ka. Regions with a highstand were located furthest away from the former LIS, where the effects from ocean syphoning and hydro-isostasy outweigh the influence of subsidence from forebulge collapse.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1986QuRes..26....3D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1986QuRes..26....3D"><span>Global ice-sheet system interlocked by <span class="hlt">sea</span> <span class="hlt">level</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Denton, George H.; Hughes, Terence J.; Karlén, Wibjörn</p> <p>1986-07-01</p> <p>Denton and Hughes (1983, Quaternary Research20, 125-144) postulated that <span class="hlt">sea</span> <span class="hlt">level</span> linked a global ice-sheet system with both terrestrial and grounded marine components during late Quaternary ice ages. Summer temperature changes near Northern Hemisphere melting margins initiated <span class="hlt">sea-level</span> fluctuations that controlled marine components in both polar hemispheres. It was further proposed that variations of this ice-sheet system amplified and transmitted Milankovitch summer half-year insolation changes between 45 and 75°N into global climatic changes. New tests of this hypothesis implicate <span class="hlt">sea</span> <span class="hlt">level</span> as a major control of the areal extent of grounded portions of the Antarctic Ice Sheet, thus fitting the concept of a globally interlocked ice-sheet system. But recent atmospheric modeling results ( Manabe and Broccoli, 1985, Journal of Geophysical Research90, 2167-2190) suggest that factors other than areal changes of the grounded Antarctic Ice Sheet strongly influenced Southern Hemisphere climate and terminated the last ice age simultaneously in both polar hemispheres. Atmospheric carbon dioxide linked to high-latitude oceans is the most likely candidate ( Shackleton and Pisias, 1985, Atmospheric carbon dioxide, orbital forcing, and climate. In "The Carbon Cycle and Atmospheric CO 2: Natural Variations Archean to Present" (E. T. Sundquest and W. S. Broecker, Eds.), pp. 303-318. Geophysical Monograph 32, American Geophysical Union, Washington, D.C.), but another potential influence was high-frequency climatic oscillations (2500 yr). It is postulated that variations in atmospheric carbon dioxide acted through an Antarctic ice shelf linked to the grounded ice sheet to produce and terminate Southern Hemisphere ice-age climate. It is further postulated that Milankovitch summer insolation combined with a warm high-frequency oscillation caused marked recession of Northern Hemisphere ice-sheet melting margins and the North Atlantic polar front about 14,000 14C yr B.P. This</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA......186K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA......186K"><span>Fractal geometry methods and neurocomputing for Caspian <span class="hlt">sea</span> <span class="hlt">level</span> forecasting</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Karimova, L.; Mukhamejanova, S.; Makarenko, N.</p> <p>2003-04-01</p> <p>In this paper a method of natural dynamical systems forecasting is proposed. This method is a result of combination of topological dynamics and deterministic chaos theories. The technique enables reconstructing a universal model of the process in question from the given data directly, which is implemented by embedding the investigated time series into Euclidean space of the proper dimension. Such a model can preserve characteristics of the attractor of a dynamical system, which is supposed to generate the time series and allows constructing a correct scheme of local multidimensional prediction. The predictor is described by a continuous nonlinear function with number of its arguments depending on embedding dimension. An artificial neural network is used to approximate the function. The method is illustrated on the example of Caspian <span class="hlt">Sea</span> <span class="hlt">level</span>. It is the largest intercontinental reservoir without water flow, which demonstrates the unique evolution on an extent of a huge time interval, represented by the recurrent change of transgressive and regressive phases, that is noticed in illegible traces of paleodata, scanty historical information and also monitoring on short instrumental period. The instrumental time series contain not enough values to trace the global variations of the <span class="hlt">sea</span> <span class="hlt">level</span>. That is why we use these measurements together with historical records. The second data are preliminary processed with the fractal interpolation procedure. This is done in order to make the two series have equal time resolutions. The appropriateness of such an interpolation is verified with the help of Hurst method. We apply the delay coordinate transformation with different delay parameters instead of the canonical Takens reconstruction procedure for embedding the time series into Euclidean space. This technique is called irregular embedding and allows investigating multicyclic dynamical systems. For the problem of Caspian <span class="hlt">sea</span> <span class="hlt">level</span> forecasting we use a version of the irregular</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRC..120.1527W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRC..120.1527W"><span>Evidence for multidecadal variability in US extreme <span class="hlt">sea</span> <span class="hlt">level</span> records</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wahl, Thomas; Chambers, Don P.</p> <p>2015-03-01</p> <p>We analyze a set of 20 tide gauge records covering the contiguous United States (US) coastline and the period from 1929 to 2013 to identify long-term trends and multidecadal variations in extreme <span class="hlt">sea</span> <span class="hlt">levels</span> (ESLs) relative to changes in mean <span class="hlt">sea</span> <span class="hlt">level</span> (MSL). Different data sampling and analysis techniques are applied to test the robustness of the results against the selected methodology. Significant but small long-term trends in ESLs above/below MSL are found at individual sites along most coastline stretches, but are mostly confined to the southeast coast and the winter season when storm surges are primarily driven by extratropical cyclones. We identify six regions with broadly coherent and considerable multidecadal ESL variations unrelated to MSL changes. Using a quasi-nonstationary extreme value analysis, we show that the latter would have caused variations in design relevant return water <span class="hlt">levels</span> (50-200 year return periods) ranging from ˜10 cm to as much as 110 cm across the six regions. The results raise questions as to the applicability of the "MSL offset method," assuming that ESL changes are primarily driven by changes in MSL without allowing for distinct long-term trends or low-frequency variations. Identifying the coherent multidecadal ESL variability is crucial in order to understand the physical driving factors. Ultimately, this information must be included into coastal design and adaptation processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910014943','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910014943"><span>Uprated OMS Engine Status-<span class="hlt">Sea</span> <span class="hlt">Level</span> Testing Results</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bertolino, J. D.; Boyd, W. C.</p> <p>1990-01-01</p> <p>The current Space Shuttle Orbital Maneuvering Engine (OME) is pressure fed, utilizing storable propellants. Performance uprating of this engine, through the use of a gas generator driven turbopump to increase operating pressure, is being pursued by the NASA Johnson Space Center (JSC). Component <span class="hlt">level</span> design, fabrication, and test activities for this engine system have been on-going since 1984. More recently, a complete engine designated the Integrated Component Test Bed (ICTB), was tested at <span class="hlt">sea</span> <span class="hlt">level</span> conditions by Aerojet. A description of the test hardware and results of the <span class="hlt">sea</span> <span class="hlt">level</span> test program are presented. These results, which include the test condition operating envelope and projected performance at altitude conditions, confirm the capability of the selected Uprated OME (UOME) configuration to meet or exceed performance and operational requirements. Engine flexibility, demonstrated through testing at two different operational mixture ratios, along with a summary of projected Space Shuttle performance enhancements using the UOME, are discussed. Planned future activities, including ICTB tests at simulated altitude conditions, and recommendations for further engine development, are also discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.5692G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.5692G"><span>Freeboard, <span class="hlt">sea</span> <span class="hlt">level</span> and dynamic topography during aggregation of a supercontinent</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Guillaume, B.; Husson, L.; Choblet, G.</p> <p>2012-04-01</p> <p>The long-term evolution of <span class="hlt">sea</span> <span class="hlt">level</span> is a combination of eustatic mechanisms (tectono-eustatism, distribution of continental masses through orogenesis and sedimentation) and non-uniform processes (dynamic topography, geoid, wander of the Earth rotation pole). Given the potentially similar amplitude of both factors, there is a bias in the observation of absolute <span class="hlt">sea</span> <span class="hlt">level</span>. Moreover, over large time-scales, and more specifically over the Wilson cycle time-scale, plate aggregation and separation are associated both with (i) variations of the flow pattern and (ii) thermal state in the mantle, which in turn may induce specific vertical motions of the surface. By changing the size of the oceanic and continental water reservoirs, large-scale dynamic topography associated with subduction or the presence of mantle plumes controls rises or drops of <span class="hlt">sea</span> <span class="hlt">level</span>, which in turn controls part of the stratigraphic record. The Earth has known periods of continental aggregation and fragmentation that redistribute the location of plate boundaries, especially the location and the length of subduction zones, that could potentially <span class="hlt">affect</span> <span class="hlt">sea</span> <span class="hlt">level</span>. The distribution of mass anomalies in the mantle with respect to continents may therefore have a significant impact. To test the possible correlation between <span class="hlt">sea</span> <span class="hlt">level</span> changes and the Wilson cycle, we decide to first focus on the Pangea, which is known to be a period during which most subductions took place beneath continents. We run a set of Earth-like instantaneous flow model using the OEDIPUS (Origin, Evolution and Dynamics of the Interiors of Planets Using Simulation) tool, which allows spherical geometries with lateral viscosity variations. In these models, Pangea is modeled by a spherical continental cap, covering 29% of the planet surface, and floating above a two-layered viscous mantle. We vary parameters such as the dip of the subducting panel, the depth reached by the slab, the viscosity structure and the plate thickness within</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016cosp...41E1677S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016cosp...41E1677S"><span>Investigation of the seasonal spatial variability of the Caspian <span class="hlt">Sea</span> <span class="hlt">level</span> by satellite altimetry.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Safarov, Elnur; Mammadov, Ramiz; Cretaux, Jean-Francois; Arsen, Adalbert; Safarov, Said; Amrahov, Elvin</p> <p>2016-07-01</p> <p><span class="hlt">Sea</span> <span class="hlt">level</span> fluctuations are among the most outstanding and debated issues of the Caspian <span class="hlt">Sea</span>. Precipitation, underground water and river input are consistent parts of the inflow of the Caspian <span class="hlt">Sea</span> water balance. The river input is also considered to be the main driver of the seasonal <span class="hlt">level</span> changes of the Caspian <span class="hlt">Sea</span>. Sufficiently large amount of this input is provided by the Volga. Although there is a good network of <span class="hlt">sea</span> <span class="hlt">level</span> stations covering the coastline of the <span class="hlt">sea</span>, these facilities are not capable to reflect the <span class="hlt">sea</span> <span class="hlt">level</span> variations over the all surface. Meanwhile, the Caspian <span class="hlt">Sea</span> is well observed by satellites Jason 1, Jason 2 and ENVISAT. Altimetric data taken from these satellites covers the surface of the <span class="hlt">sea</span> much better than the data from the in-situ network stations. In this paper we investigate the spatial variability of the <span class="hlt">sea</span> <span class="hlt">level</span> that could provide more insight into the influence of river input (especially the Volga river), precipitation and other hydro-meteorological parameters on the Caspian <span class="hlt">Sea</span> <span class="hlt">level</span>.The altimetric data was averaged per every 10 square kilometers through all the tracks by means of the pre-prepared program made especially for this work. Also new maps of seasonal spatial variability of amplitude and phase of the annual signal of the Caspian <span class="hlt">Sea</span> <span class="hlt">level</span> for each investigated satellite were created by employing ARCGIS software. Moreover, these peaks of <span class="hlt">sea</span> <span class="hlt">level</span> amplitude and phase of annual signal results were comparatively analyzed with the corresponding river discharge of the Volga.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007GeoRL..3410405G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007GeoRL..3410405G"><span>Mediterranean <span class="hlt">Sea</span> <span class="hlt">level</span> variations during the Messinian salinity crisis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gargani, Julien; Rigollet, Christophe</p> <p>2007-05-01</p> <p>The Mediterranean Basin has not always been connected to the Atlantic Ocean. During the Messinian salinity crisis (MSC), the Mediterranean <span class="hlt">Sea</span> became progressively isolated by a complex combination of tectonic and glacio-eustatic processes. When isolated, the Mediterranean water <span class="hlt">level</span> depends on the hydrological flux and is expected to vary significantly. The amplitude and number of large water <span class="hlt">level</span> fluctuations in the isolated Mediterranean is still controversial, despite numerous geological investigations. The observation of 3-5 surfaces of erosion in the Nile delta (Eastern Basin) provides new elements for understanding the dynamics of the MSC. Our model demonstrates that numerous water <span class="hlt">level</span> falls of short duration may explain the preservation of a discontinuous river profile at ~-500 m and ~-1500 m in the Western Basin, as well as the existence of deep surfaces of erosion in the Eastern Basin.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006GPC....53..108K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006GPC....53..108K"><span>Biogenic and abiogenic sedimentation in the northern East China <span class="hlt">Sea</span> in response to <span class="hlt">sea-level</span> change during the Late Pleistocene</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kawahata, Hodaka; Nohara, Masato; Aoki, Kaori; Minoshima, Kayo; Gupta, Lallan P.</p> <p>2006-08-01</p> <p>In order to understand fluctuations in terrestrial and marine environments in response to <span class="hlt">sea-level</span> change during the last 42 ky, we investigated sedimentation of biogenic and abiogenic components in core MD982195, collected from the northern East China <span class="hlt">Sea</span> (ECS), one of the largest marginal <span class="hlt">seas</span> in the world. Amino acids (AAs), major nitrogen compounds in marine organic matter (OM), can be protected inside biogenic material and survive the decomposition process. The total AAs were highly correlated with organic carbon (OC) ( r = 0.91; p < 0.05) but less with total nitrogen (TN) ( r = 0.76; p < 0.05). Therefore, total AAs and OC contents should reflect primary production (PP) more than TN in core MD982195. PP was approximately constant during 42-15 ka, increased in 15-14 ka was kept constant until 7 ka. Then PP increased from 5 ka to the present. IMAGES program is generally interested in high-resolutional reconstruction of paleo-environments in the area with high sedimentation rate, which is mainly due to abundant supply of lithogenic matter. The positive correlation of lithogenic matter with nonarboreal pollens (NAP) abundance suggests that lithogenic matter and NAP were mainly transported from the coastal lowlands created by the large drop in <span class="hlt">sea</span> <span class="hlt">level</span> during the glacial period. Large, millennial-scale fluctuations in <span class="hlt">sea</span>-surface temperature and salinity did not always correspond to sedimentation pulses of OC and lithogenic matter. Sedimentation of biogenic and abiogenic components was more <span class="hlt">affected</span> by <span class="hlt">sea-level</span> change, which controls the positions of the coastline and river mouths and the presence of terrestrial environments on the exposed continental shelf. The Japan <span class="hlt">Sea</span> is also sensitive to <span class="hlt">sea-level</span> change because of the shallow sills connecting it to other ocean basins.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.5572B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.5572B"><span>IODP Expedition 359: Maldives Monsoon and <span class="hlt">Sea</span> <span class="hlt">Level</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Betzler, Christian; Eberli, Gregor; Zarikian, Carlos</p> <p>2016-04-01</p> <p>Drilling the carbonate platforms and drifts in the Maldives aimed to recover the marine tropical record of the Neogene <span class="hlt">sea-level</span> changes and the onset of the monsoon related current system in the Indian Ocean. To reach this goal, eight sites were drilled along two transects in the Kardiva Channel in the Inner <span class="hlt">Sea</span> of the Maldives during IODP Expedition 359. The recovered cores and log data retrieved the material to achieve all the objectives set for the expedition. The most arresting accomplishment is the documentation of how the <span class="hlt">sea</span> <span class="hlt">level</span> controlled the carbonate platform system that was thriving during the Miocene Climate Optimum abruptly transitioned into a current-dominated system in the late Middle Miocene. This transition is linked to the onset of an early intensification of the Indian monsoon and the coeval demise of some of the Maldivian platforms. Cores and downhole logs allowed producing a solid record and reconstructing the Neogene environmental changes in the central Indian Ocean. Preliminary shipboard analyses allow a precise dating of this major paleoclimatological and paleoceanographical changes, as it also applies for the extension of the Oxygen Minimum Zone (OMZ) into this part of the Indian Ocean. Coring produced a solid framework to foster the post-cruise research of these distinct topics. In addition, complete spliced sections and logging at key sites during Expedition 359 provide the potential to assemble a cycle-based astrochronology for the Neogene section in the Maldives. This high-resolution chronology will allow: 1) independent ages to be assigned to key biostratigraphic events in the Maldives for comparison with those from other tropical regions; 2) more precise ages for the major sequence boundaries and unconformities; and 3) evaluation of higher-resolution sedimentation rate variations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70016863','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70016863"><span>General circulation model simulations of winter and summer <span class="hlt">sea-level</span> pressures over North America</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>McCabe, G.J.; Legates, D.R.</p> <p>1992-01-01</p> <p>In this paper, observed <span class="hlt">sea-level</span> pressures were used to evaluate winter and summer <span class="hlt">sea-level</span> pressures over North America simulated by the Goddard Institute for Space Studies (GISS) and the Geophysical Fluid Dynamics Laboratory (GFDL) general circulation models. The objective of the study is to determine how similar the spatial and temporal distributions of GCM-simulated daily <span class="hlt">sea-level</span> pressures over North America are to observed distributions. Overall, both models are better at reproducing observed within-season variance of winter and summer <span class="hlt">sea-level</span> pressures than they are at simulating the magnitude of mean winter and summer <span class="hlt">sea-level</span> pressures. -from Authors</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11679666','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11679666"><span><span class="hlt">Sea</span> <span class="hlt">level</span> rise during past 40 years determined from satellite and in situ observations.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cabanes, C; Cazenave, A; Le Provost, C</p> <p>2001-10-26</p> <p>The 3.2 +/- 0.2 millimeter per year global mean <span class="hlt">sea</span> <span class="hlt">level</span> rise observed by the Topex/Poseidon satellite over 1993-98 is fully explained by thermal expansion of the oceans. For the period 1955-96, <span class="hlt">sea</span> <span class="hlt">level</span> rise derived from tide gauge data agrees well with thermal expansion computed at the same locations. However, we find that subsampling the thermosteric <span class="hlt">sea</span> <span class="hlt">level</span> at usual tide gauge positions leads to a thermosteric <span class="hlt">sea</span> <span class="hlt">level</span> rise twice as large as the "true" global mean. As a possible consequence, the 20th century <span class="hlt">sea</span> <span class="hlt">level</span> rise estimated from tide gauge records may have been overestimated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.C42A..04B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.C42A..04B"><span>Contribution of Iceland's Ice Caps to <span class="hlt">Sea</span> <span class="hlt">Level</span> Change</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bjornsson, H.; Gudmundsson, S.; Pálsson, F.; Magnusson, E.; Sigurdsson, O.; Johannesson, T.; Thorsteinsson, T.; Berthier, E.</p> <p>2011-12-01</p> <p>We report on the volume change of Icelandic ice caps during several time intervals from the 1980s until present. Changes in ice volume have been monitored by both annual mass balance measurements on the glaciers and by comparison of multi-temporal digital surface elevation models derived from various satellite and airborne remote observations. The glaciers' mass budgets have declined significantly, from being close to zero in the 1980s and early 1990s, to becoming on average negative by -0.7 to -1.8 m w.e. per year since the mid 1990s. This reduction in mass balance is related to rapid climate warming in Iceland, approx. 1.5 °C since the early 1980s. High mass balance sensitivities of -1 to -2 m w. e. per °C are identified. The current contribution of Icelandic ice caps to <span class="hlt">sea</span> <span class="hlt">level</span> change is estimated to be ~0.03 mm SLE per year. Icelandic ice caps contain in total approx. 3,600 cubic km of ice, which if melted would raise <span class="hlt">sea</span> <span class="hlt">level</span> by approx. 1 cm.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990QuRes..33....1H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990QuRes..33....1H"><span>South Carolina interglacial sites and stage 5 <span class="hlt">sea</span> <span class="hlt">levels</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hollin, John T.; Hearty, Paul J.</p> <p>1990-01-01</p> <p>Amino acid and other studies have been made on the 30-km Pleistocene sections of the Intracoastal Waterway between Myrtle Beach and Little River, South Carolina. Our ratios differentiate the long-established Waccamaw (oldest), Canepatch, and Socastee formations. The ratios from the four laboratories that have worked in this area agree very well, and apparent conflicts with U-series dates may merely reflect an abundance of reworked corals. Our amino acid correlations with U-series coral dates in South Carolina, Bermuda, and the Mediterranean all argue that the classical Canepatch and its Horry Clay date from isotope stage 5e and not, as has been implied, from stage 7, 9, 11, or 13. Excavations and erosion have increased position-fixing problems along the Waterway, and "Canepatch" amino acid ratios and U-series dates (460,000 ± 100,000 yr B.P.) at "ICW5" may be from an older unit. The Canepatch shows the double marine transgression visible in many stage 5e deposits. Pollen shows that the second transgression occurred late in the interglaciation, and stratigraphic studies show that it reached 14 m. It therefore fits very well Antarctic ice-surge models of stage 5 <span class="hlt">sea</span> <span class="hlt">level</span> and climate. The Socastee adds to the evidence for one or more <span class="hlt">sea</span> <span class="hlt">levels</span> above 0 m late in stage 5.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017OcSci..13...47B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017OcSci..13...47B"><span>Changes in extreme regional <span class="hlt">sea</span> <span class="hlt">level</span> under global warming</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brunnabend, S.-E.; Dijkstra, H. A.; Kliphuis, M. A.; Bal, H. E.; Seinstra, F.; van Werkhoven, B.; Maassen, J.; van Meersbergen, M.</p> <p>2017-01-01</p> <p>An important contribution to future changes in regional <span class="hlt">sea</span> <span class="hlt">level</span> extremes is due to the changes in intrinsic ocean variability, in particular ocean eddies. Here, we study a scenario of future dynamic <span class="hlt">sea</span> <span class="hlt">level</span> (DSL) extremes using a high-resolution version of the Parallel Ocean Program and generalized extreme value theory. This model is forced with atmospheric fluxes from a coupled climate model which has been integrated under the IPCC-SRES-A1B scenario over the period 2000-2100. Changes in 10-year return time DSL extremes are very inhomogeneous over the globe and are related to changes in ocean currents and corresponding regional shifts in ocean eddy pathways. In this scenario, several regions in the North Atlantic experience an increase in mean DSL of up to 0.4 m over the period 2000-2100. DSL extremes with a 10-year return time increase up to 0.2 m with largest values in the northern and eastern Atlantic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMGC13A1051K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMGC13A1051K"><span>Eco-technological management of Tuvalu against <span class="hlt">sea</span> <span class="hlt">level</span> rise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kayanne, H.</p> <p>2012-12-01</p> <p>Atoll island is formed and maintained by sand production, transportation and sedimentation process. Major component of sand in the Pacific atolls is foraminifera, which is produced on the ocean-side reef flat, and then transported from the ocean-side to the lagoon-side coast through channels between the islands. Sand is then transported along the lagoon-side coast by longshore current, and finally deposited to nourish sandy beach. At present, however, this natural process has been deteriorated by local human stresses. High production of foraminifera and corals are degraded by human waste. Transportation of sand from the ocean to the lagoon is blocked by a causeway, and longshore transportation and sedimentation along the lagoon coast is prevented by jetties, dredges and upright seawalls. All these local factors severely reduce natural resilience and increase vulnerability against the projected future <span class="hlt">sea</span> <span class="hlt">level</span> rise and the global changes. Countermeasure plans must be based on and must not conflict with the natural island formation process. We launched "Eco-technological management of Tuvalu against <span class="hlt">sea</span> <span class="hlt">level</span> rise" under Science and Technology Research Partnership for Sustainable Development funded by JICA and JST. The goal of this project is to regenerate sandy beach along Fongafale Island, Funrafuti Atoll Tuvalu by rehabilitation of production, transportation and sedimentation process including establishing foraminifera culture system.; Fig. 1 Aerial view of Fongafale Is., Funafuti Atoll, Tuvalu.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.9121S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.9121S"><span>A High School Project Seminar on <span class="hlt">Sea</span> <span class="hlt">Level</span> Rise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Seitz, M.; Bosch, W.</p> <p>2012-04-01</p> <p>In Bavaria the curriculum of the upper grade of high school includes a so called project seminar, running over one and a half year. The aims of the seminar are to let the pupils learn to work on a specific topic, to organize themselves in a team, to improve their soft skills and become familiar with the working life. The topic of the project seminar, jointly organized by the Bertold-Brecht-Gymnasium in Munich and the Deutsche Geodätische Forschungsinstitut (DGFI) was on the "Global <span class="hlt">sea</span> <span class="hlt">level</span> rise". A team of 13 pupils computed the mean <span class="hlt">sea</span> <span class="hlt">level</span> rise by using on the one hand altimetry data of TOPEX, Jason-1 and Jason2 and on the other hand data of globally distributed tide gauges, corrected for vertical crustal movements derived from GPS products. The results of the two independent approaches were compared with each other and discussed considering also statements and discussions found in press, TV, and the web. Finally, a presentation was prepared and presented at school.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5875484','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5875484"><span>Vulnerability of the US to future <span class="hlt">sea</span> <span class="hlt">level</span> rise</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gornitz, V. . Goddard Inst. for Space Studies); White, T.W.; Cushman, R.M. )</p> <p>1991-01-01</p> <p>The differential vulnerability of the conterminous United States to future <span class="hlt">sea</span> <span class="hlt">level</span> rise from greenhouse climate warming is assessed, using a coastal hazards data base. This data contains information on seven variables relating to inundation and erosion risks. High risk shorelines are characterized by low relief, erodible substrate, subsidence, shoreline retreat, and high wave/tide energies. Very high risk shorelines on the Atlantic Coast (Coastal Vulnerability Index {ge}33.0) include the outer coast of the Delmarva Peninsula, northern Cape Hatteras, and segments of New Jersey, Georgia and South Carolina. Louisiana and sections of Texas are potentially the most vulnerable, due to anomalously high relative <span class="hlt">sea</span> <span class="hlt">level</span> rise and erosion, coupled with low elevation and mobile sediments. Although the Pacific Coast is generally the least vulnerable, because of its rugged relief and erosion-resistant substrate, the high geographic variability leads to several exceptions, such as the San Joaquin-Sacramento Delta area, the barrier beaches of Oregon and Washington, and parts of the Puget Sound Lowlands. 31 refs., 2 figs., 3 tabs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70030065','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70030065"><span><span class="hlt">Sea</span> <span class="hlt">level</span> fluctuations in central California at subtidal to decadal and longer time scales with implications for San Francisco Bay, California</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Ryan, H.F.; Noble, M.A.</p> <p>2007-01-01</p> <p><span class="hlt">Sea</span> <span class="hlt">level</span> elevations from near the mouth of San Francisco Bay are used to describe the low-frequency variability of forcing of the coastal ocean on the Bay at a variety of temporal scales. About 90% of subtidal fluctuations in <span class="hlt">sea</span> <span class="hlt">level</span> in San Francisco Bay are driven by the <span class="hlt">sea</span> <span class="hlt">level</span> variations in the coastal ocean that propagate into the Bay at the estuary mouth. We use the 100-year <span class="hlt">sea</span> <span class="hlt">level</span> record available at San Francisco to document a 1.9 mm/yr mean <span class="hlt">sea</span> <span class="hlt">level</span> rise, and to determine fluctuations related to El Nino-Southern Oscillation (ENSO) and other climatic events. At time scales greater than 1 year, ENSO dominates the <span class="hlt">sea</span> <span class="hlt">level</span> signal and can result in fluctuations in <span class="hlt">sea</span> <span class="hlt">level</span> of 10-15 cm. Alongshore wind stress data from central California are also analyzed to determine the impact of changes in coastal elevation at the mouth of San Francisco Bay within the synoptic wind band of 2-30 days. At least 40% of the subtidal fluctuations in <span class="hlt">sea</span> <span class="hlt">level</span> of the Bay are tied to the large-scale regional wind field <span class="hlt">affecting</span> <span class="hlt">sea</span> <span class="hlt">level</span> variations in the coastal ocean, with little local, direct wind forcing of the Bay itself. The majority of the subtidal <span class="hlt">sea</span> <span class="hlt">level</span> fluctuations within the Bay that are not related to the coastal ocean <span class="hlt">sea</span> <span class="hlt">level</span> signal are forced by an east-west <span class="hlt">sea</span> <span class="hlt">level</span> gradient resulting from tidally induced variations in <span class="hlt">sea</span> <span class="hlt">level</span> at specific beat frequencies that are enhanced in the northern reach of the Bay. River discharge into the Bay through the Sacramento and San Joaquin River Delta also contributes to the east-west gradient, but to a lesser degree. ?? 2007 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1611423T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1611423T"><span>New developments in spatial interpolation methods of <span class="hlt">Sea-Level</span> Anomalies in the Mediterranean <span class="hlt">Sea</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Troupin, Charles; Barth, Alexander; Beckers, Jean-Marie; Pascual, Ananda</p> <p>2014-05-01</p> <p>The gridding of along-track <span class="hlt">Sea-Level</span> Anomalies (SLA) measured by a constellation of satellites has numerous applications in oceanography, such as model validation, data assimilation or eddy tracking. Optimal Interpolation (OI) is often the preferred method for this task, as it leads to the lowest expected error and provides an error field associated to the analysed field. However, the numerical cost of the method may limit its utilization in situations where the number of data points is significant. Furthermore, the separation of non-adjacent regions with OI requires adaptation of the code, leading to a further increase of the numerical cost. To solve these issues, the Data-Interpolating Variational Analysis (DIVA), a technique designed to produce gridded from sparse in situ measurements, is applied on SLA data in the Mediterranean <span class="hlt">Sea</span>. DIVA and OI have been shown to be equivalent (provided some assumptions on the covariances are made). The main difference lies in the covariance function, which is not explicitly formulated in DIVA. The particular spatial and temporal distributions of measurements required adaptation in the Software tool (data format, parameter determinations, ...). These adaptation are presented in the poster. The daily analysed and error fields obtained with this technique are compared with available products such as the gridded field from the Archiving, Validation and Interpretation of Satellite Oceanographic data (AVISO) data server. The comparison reveals an overall good agreement between the products. The time evolution of the mean error field evidences the need of a large number of simultaneous altimetry satellites: in period during which 4 satellites are available, the mean error is on the order of 17.5%, while when only 2 satellites are available, the error exceeds 25%. Finally, we propose the use <span class="hlt">sea</span> currents to improve the results of the interpolation, especially in the coastal area. These currents can be constructed from the bathymetry</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006cosp...36.1415L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006cosp...36.1415L"><span>Interannual Trends in Southern Ocean <span class="hlt">Sea</span> Surface Temperatures and <span class="hlt">Sea</span> <span class="hlt">Level</span> from Remote Sensing Data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lebedev, S. A.</p> <p></p> <p>As is shown in last years researches climate changes in Antarctic result in interannual increase trend of surface air temperature and decrease of ice thickness These tendencies are must try in the Southern Ocean hydrological regime For that next remote sensing data AVHRR MCSST data and satellite altimetry data merged data of mission ERS TOPEX Poseidon Jason-1 ENVISAT GFO-1 are used to this task which give information about <span class="hlt">sea</span> surface temperature SST and <span class="hlt">sea</span> <span class="hlt">level</span> anomaly SLA correspondingly According to obtained results SST has positive trend more 0 01 oC yr for 23-yr record 1982-2005 within 300-1000 km northward Antarctic coast However on average for the Southern Ocean SST have negative trend about -0 018 -0 035 oC yr In area of Pacific-Antarctic Ridge and of southern part of Mid Atlantic Ridge decrease rate is more than -0 075 oC yr SLA increases in all area of the Southern Ocean and has average rate about 0 024 -0 026 cm yr for 12-yr record 1993-2005 Around Antarctic SST rate good correspond with the trend analysis of surface air temperature of 8722 0 042 - 0 067oC yr inferred from the satellite 20-yr record Comiso 2000 Nevertheless the observed cooling is intriguing especially since it is compatible with the observed trend in the <span class="hlt">sea</span> ice cover In the <span class="hlt">sea</span> ice regions the northernmost positions of the ice edge are shown to be influenced by alternating warm and cold anomalies around the continent This work was partly supported by the Russian Fund of Basic Research Grant 06-05-65061</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SGeo..tmp...47J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SGeo..tmp...47J"><span>The Twentieth-Century <span class="hlt">Sea</span> <span class="hlt">Level</span> Budget: Recent Progress and Challenges</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jevrejeva, S.; Matthews, A.; Slangen, A.</p> <p>2016-12-01</p> <p>For coastal areas, given the large and growing concentration of population and economic activity, as well as the importance of coastal ecosystems, <span class="hlt">sea</span> <span class="hlt">level</span> rise is one of the most damaging aspects of the warming climate. Huge progress in quantifying the cause of <span class="hlt">sea</span> <span class="hlt">level</span> rise and closure of <span class="hlt">sea</span> <span class="hlt">level</span> budget for the period since the 1990s has been made mainly due to the development of the global observing system for <span class="hlt">sea</span> <span class="hlt">level</span> components and total <span class="hlt">sea</span> <span class="hlt">levels</span>. We suggest that a large spread (1.2 ± 0.2-1.9 ± 0.3 mm year-1) in estimates of <span class="hlt">sea</span> <span class="hlt">level</span> rise during the twentieth century from several reconstructions demonstrates the need for and importance of the rescue of historical observations from tide gauges, with a focus on the beginning of the twentieth century. Understanding the physical mechanisms contributing to <span class="hlt">sea</span> <span class="hlt">level</span> rise and controlling the variability of <span class="hlt">sea</span> <span class="hlt">level</span> over the past few 100 years are a challenging task. In this study, we provide an overview of the progress in understanding the cause of <span class="hlt">sea</span> <span class="hlt">level</span> rise during the twentieth century and highlight the main challenges facing the interdisciplinary <span class="hlt">sea</span> <span class="hlt">level</span> community in understanding the complex nature of <span class="hlt">sea</span> <span class="hlt">level</span> changes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6689563','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6689563"><span><span class="hlt">Sea</span> <span class="hlt">level</span> controls on carbonate facies associated with Mesozoic and Cenozoic hydrocarbon fields</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kendall, C.G.S.C. ); Alsharhan, A. ); Stoudt, D. ); Bowen, B.</p> <p>1990-05-01</p> <p>Abundant subsurface data for the Mesozoic and Cenozoic sections of the Gulf Coast of the US and the Middle East makes it possible to track the relationship of shelf carbonates and evaporites with minor clastics to eustatic <span class="hlt">sea</span> <span class="hlt">level</span>. Since sedimentary stratigraphy for both regions was driven by gentle tectonic subsidence punctuated by eustatic <span class="hlt">sea</span> <span class="hlt">level</span> variations, the major hydrocarbon fields from these areas can be classified in terms of <span class="hlt">sea</span> <span class="hlt">level</span> behavior at the time of the deposition of the reservoir section. With the exception of chalks, most of these carbonate hydrocarbon fields can be related to highstand system tracts and include (1) keep-up plays with sheet-like geometry formed when carbonate accumulation matched <span class="hlt">sea</span> <span class="hlt">level</span> rise, aggrading to form shoaling-upward cycles during <span class="hlt">sea</span> <span class="hlt">level</span> highstands; (2) give-up plays in which carbonate accumulation was unable to match <span class="hlt">sea</span> <span class="hlt">level</span> rise and catch-up plays in which carbonate accumulation initially was unable to keep pace with the <span class="hlt">sea</span> <span class="hlt">level</span> rise, but then aggraded to <span class="hlt">sea</span> <span class="hlt">level</span> forming lense-like geometry on drowned shelves downslope from carbonate margins during and following rapid <span class="hlt">sea</span> <span class="hlt">level</span> rises; and (3) plays with the prograded discontinuous clinoform geometry of the platform margin, formed during stillstands by carbonate accumulation that not only kept-up with the <span class="hlt">sea</span> <span class="hlt">level</span> rise but accumulated in a seaward direction. Source rocks for these carbonate reservoirs often formed during rapid <span class="hlt">sea</span> <span class="hlt">level</span> rises whereas the reservoir seals are usually shales, dense limestones and/or evaporites.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SGeo...38..295J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SGeo...38..295J"><span>The Twentieth-Century <span class="hlt">Sea</span> <span class="hlt">Level</span> Budget: Recent Progress and Challenges</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jevrejeva, S.; Matthews, A.; Slangen, A.</p> <p>2017-01-01</p> <p>For coastal areas, given the large and growing concentration of population and economic activity, as well as the importance of coastal ecosystems, <span class="hlt">sea</span> <span class="hlt">level</span> rise is one of the most damaging aspects of the warming climate. Huge progress in quantifying the cause of <span class="hlt">sea</span> <span class="hlt">level</span> rise and closure of <span class="hlt">sea</span> <span class="hlt">level</span> budget for the period since the 1990s has been made mainly due to the development of the global observing system for <span class="hlt">sea</span> <span class="hlt">level</span> components and total <span class="hlt">sea</span> <span class="hlt">levels</span>. We suggest that a large spread (1.2 ± 0.2-1.9 ± 0.3 mm year-1) in estimates of <span class="hlt">sea</span> <span class="hlt">level</span> rise during the twentieth century from several reconstructions demonstrates the need for and importance of the rescue of historical observations from tide gauges, with a focus on the beginning of the twentieth century. Understanding the physical mechanisms contributing to <span class="hlt">sea</span> <span class="hlt">level</span> rise and controlling the variability of <span class="hlt">sea</span> <span class="hlt">level</span> over the past few 100 years are a challenging task. In this study, we provide an overview of the progress in understanding the cause of <span class="hlt">sea</span> <span class="hlt">level</span> rise during the twentieth century and highlight the main challenges facing the interdisciplinary <span class="hlt">sea</span> <span class="hlt">level</span> community in understanding the complex nature of <span class="hlt">sea</span> <span class="hlt">level</span> changes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21690367','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21690367"><span>Climate related <span class="hlt">sea-level</span> variations over the past two millennia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kemp, Andrew C; Horton, Benjamin P; Donnelly, Jeffrey P; Mann, Michael E; Vermeer, Martin; Rahmstorf, Stefan</p> <p>2011-07-05</p> <p>We present new <span class="hlt">sea-level</span> reconstructions for the past 2100 y based on salt-marsh sedimentary sequences from the US Atlantic coast. The data from North Carolina reveal four phases of persistent <span class="hlt">sea-level</span> change after correction for glacial isostatic adjustment. <span class="hlt">Sea</span> <span class="hlt">level</span> was stable from at least BC 100 until AD 950. <span class="hlt">Sea</span> <span class="hlt">level</span> then increased for 400 y at a rate of 0.6 mm/y, followed by a further period of stable, or slightly falling, <span class="hlt">sea</span> <span class="hlt">level</span> that persisted until the late 19th century. Since then, <span class="hlt">sea</span> <span class="hlt">level</span> has risen at an average rate of 2.1 mm/y, representing the steepest century-scale increase of the past two millennia. This rate was initiated between AD 1865 and 1892. Using an extended semiempirical modeling approach, we show that these <span class="hlt">sea-level</span> changes are consistent with global temperature for at least the past millennium.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AcO....76...39W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AcO....76...39W"><span>Does distance from the <span class="hlt">sea</span> <span class="hlt">affect</span> a soil microarthropod community?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wasserstrom, Haggai; Steinberger, Yosef</p> <p>2016-10-01</p> <p>Coastal sand dunes are dynamic ecosystems characterized by strong abiotic gradients from the seashore inland. Due to significant differences in the abiotic parameters in such an environment, there is great interest in biotic adaptation in these habitats. The aim of the present study, which was conducted in the northern Sharon sand-dune area of Israel, was to illustrate the spatial changes of a soil microarthropod community along a gradient from the seashore inland. Soil samples were collected from the 0-10 cm depth at five locations at different distances, from the seashore inland. Samples were taken from the bare open spaces during the wet winter and dry summer seasons. The soil microarthropod community exhibited dependence both on seasonality and sampling location across the gradient. The community was more abundant during the wet winter seasons, with an increasing trend from the shore inland, while during the dry summers, such a trend was not observed and community density was lower. The dominant groups within soil Acari were Prostigmata and Endeostigmata, groups known to have many representatives with adaptation to xeric or psammic environments. In addition, mite diversity tended to be higher at the more distant locations from the seashore, and lower at the closer locations, a trend that appeared only during the wet winters. This study demonstrated the heterogeneity of a soil microarthropod community in a coastal dune field in a Mediterranean ecosystem, indicating that the gradient abiotic parameters also <span class="hlt">affect</span> the abundance and composition of a soil microarthropod community in sand dunes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999QuRes..51..124D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999QuRes..51..124D"><span>Holocene <span class="hlt">Sea-Level</span> Record on Funafuti and Potential Impact of Global Warming on Central Pacific Atolls</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dickinson, William R.</p> <p>1999-03-01</p> <p>Geomorphic features inherited from the mid-Holocene glacio-hydro-isostatic <span class="hlt">sea-level</span> highstand that <span class="hlt">affected</span> the central Pacific region influence the susceptibility of atoll islets to potentially enhanced wave erosion associated with rise in <span class="hlt">sea</span> <span class="hlt">level</span> from global warming. Shoreline morphology on multiple islets of Funafuti atoll in central Tuvalu reflects a relative mid-Holocene <span class="hlt">sea-level</span> highstand 2.2-2.4 m above modern <span class="hlt">sea</span> <span class="hlt">level</span>. Typical islets are composed of unconsolidated post-mid-Holocene sediment resting disconformably on cemented coral rubble formed beneath now-emergent mid-Holocene reef flats. Exposed remnants of the lithified islet foundations serve as resistant buttresses protecting the flanks of atoll islets from wave attack. Islets lacking cemented mid-Holocene deposits as part of their internal structure are migratory sand cays with unstable shorelines. Any future <span class="hlt">sea-level</span> rise ≥0.75 m, bringing high tide above the elevation of mid-Holocene low tide, might trigger enhanced wave erosion of stable atoll islets by overtopping the indurated mid-Holocene reef platforms. As analogous threshold relations are inferred for other central Pacific atolls, the risk of future inundation of island nations cannot be evaluated solely in terms of expected <span class="hlt">sea-level</span> rise with respect to gross islet elevations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GPC...149...20J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GPC...149...20J"><span><span class="hlt">Sea</span> <span class="hlt">level</span> change from BeiDou Navigation Satellite System-Reflectometry (BDS-R): First results and evaluation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jin, Shuanggen; Qian, Xiaodong; Wu, X.</p> <p>2017-02-01</p> <p><span class="hlt">Sea</span> <span class="hlt">level</span> changes <span class="hlt">affect</span> human living environments, particularly ocean coasts. The tide gauges (TG) can measure <span class="hlt">sea</span> <span class="hlt">level</span> change, while it is the relative variations with respect to the land. Recently, GPS-Reflectometry (GPS-R) has been demonstrated to measure <span class="hlt">sea</span> <span class="hlt">level</span> change as an altimetry. With the rapid development of China's BeiDou Navigation Satellite System (BDS), it may provide a new possible opportunity to monitor <span class="hlt">sea</span> <span class="hlt">level</span> changes with three frequencies (L2, L6 and L7). In this paper, BDS-Reflectometry (BDS-R) is the first time used to estimate the <span class="hlt">sea</span> <span class="hlt">level</span> changes based on Signal-to-Noise Ratio (SNR) data and triple-frequency phase and code combinations, which are compared to tide gauge observations. Results show that <span class="hlt">sea</span> <span class="hlt">level</span> changes from BDS SNR and phase combination have a good agreement with correlation coefficients of 0.83-0.91 and RMSEs of less than 0.6 m, while BDS code combination is not as good as others. Furthermore, a new negative linear model between phase and code peak frequencies and tide gauge observations is further obtained and analyzed, which improves the results from three-frequency phase and code combinations with the RMSE of about 10 cm and 18 cm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70035184','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70035184"><span>Relative <span class="hlt">sea-level</span> rise as indicated by gage data along the Mississippi and Alabama Gulf Coasts</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Van Wilson, Jr.</p> <p>2004-01-01</p> <p>Global warming, or the increasing of earth's temperatures, leads to rising <span class="hlt">sea</span> <span class="hlt">level</span> as polar ice caps and mountain glaciers melt and ocean water undergoes thermal expansion. Tidal records collected by the U.S. Army Corps of Engineers (COE), Mobile District, at Gulfport, Biloxi, and Pascagoula, Mississippi, and at Mobile, Alabama, indicate trends of water-surface elevations increasing with time (relative <span class="hlt">sea-level</span> rise). The trends indicated by the COE data were compared to relative <span class="hlt">sea-level</span> trends indicated by the National Ocean Survey gages in the Gulf of Mexico. The average global rate of <span class="hlt">sea</span> <span class="hlt">level</span> rise has been suggested to approach about 2 mm/yr (0.007 ft/yr). Some leading scientists have suggested rates of <span class="hlt">sea</span> <span class="hlt">level</span> rise that are greater than 2 mm/yr, when accounting for effects of greenhouse gas emissions. As the <span class="hlt">sea</span> <span class="hlt">level</span> rises and inundates the coastal plain, structures along the existing coast and structures located in the back bays of estuaries will be even more adversely <span class="hlt">affected</span> by future flooding. Also, if the land surface adjacent to the water also sinks due to soil compaction and other geologic processes (collectively call subsidence), additional land will be inundated. Copyright ASCE 2004.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/10952309','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/10952309"><span>Ocean circulation off east Antarctica <span class="hlt">affects</span> ecosystem structure and <span class="hlt">sea</span>-ice extent.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nicol, S; Pauly, T; Bindoff, N L; Wright, S; Thiele, D; Hosie, G W; Strutton, P G; Woehler, E</p> <p>2000-08-03</p> <p><span class="hlt">Sea</span> ice and oceanic boundaries have a dominant effect in structuring Antarctic marine ecosystems. Satellite imagery and historical data have identified the southern boundary of the Antarctic Circumpolar Current as a site of enhanced biological productivity. Meso-scale surveys off the Antarctic peninsula have related the abundances of Antarctic krill (Euphausia superba) and salps (Salpa thompsoni) to inter-annual variations in <span class="hlt">sea</span>-ice extent. Here we have examined the ecosystem structure and oceanography spanning 3,500 km of the east Antarctic coastline, linking the scales of local surveys and global observations. Between 80 degrees and 150 degrees E there is a threefold variation in the extent of annual <span class="hlt">sea</span>-ice cover, enabling us to examine the regional effects of <span class="hlt">sea</span> ice and ocean circulation on biological productivity. Phytoplankton, primary productivity, Antarctic krill, whales and seabirds were concentrated where winter <span class="hlt">sea</span>-ice extent is maximal, whereas salps were located where the <span class="hlt">sea</span>-ice extent is minimal. We found enhanced biological activity south of the southern boundary of the Antarctic Circumpolar Current rather than in association with it. We propose that along this coastline ocean circulation determines both the <span class="hlt">sea</span>-ice conditions and the <span class="hlt">level</span> of biological productivity at all trophic <span class="hlt">levels</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014CorRe..33..819H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014CorRe..33..819H"><span>detrimentally <span class="hlt">affects</span> tissue regeneration of Red <span class="hlt">Sea</span> corals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Horwitz, Rael; Fine, Maoz</p> <p>2014-09-01</p> <p>Ocean acidification (OA) from rising atmospheric carbon dioxide (CO2) is threatening the future of coral reef ecosystems. Mounting experimental evidence suggests that OA negatively impacts fundamental life functions of scleractinian corals, including growth and sexual reproduction. Although regeneration is regarded as a chief life function in scleractinian corals and essential to maintain the colony's integrity, the effect of OA on regeneration processes has not yet been investigated. To evaluate the effects of OA on regeneration, the common Indo-Pacific corals Porites sp., Favia favus, Acropora eurystoma, and Stylophora pistillata were inflicted with lesions (314-350 mm2, depending on species) and incubated in different pCO2: (1) ambient seawater (400 µatm, pH 8.1), (2) intermediate (1,800 µatm, pH 7.6), and (3) high (4,000 µatm, pH 7.3) for extended periods of time (60-120 d). While all coral species after 60 d had significantly higher tissue regeneration in ambient conditions as compared to the intermediate and high treatments, reduction in regeneration rate was more pronounced in the slow-growing massive Porites sp. and F. favus than the relatively fast-growing, branching S. pistillata and A. eurystoma. This coincided with reduced tissue biomass of Porites sp., F. favus, and A. eurystoma in higher pCO2, but not in S. pistillata. Porites sp., F. favus, and S. pistillata also experienced a decrease in Symbiodinium density in higher pCO2, while in A. eurystoma there was no change. We hypothesize that a lowered regenerative capacity under elevated pCO2 may be related to resource trade-offs, energy cost of acid/base regulation, and/or decrease in total energy budget. This is the first study to demonstrate that elevated pCO2 could have a compounding influence on coral regeneration following injury, potentially <span class="hlt">affecting</span> the capacity of reef corals to recover following physical disturbance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.5098J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.5098J"><span>Constraining mid to late Holocene <span class="hlt">sea</span> <span class="hlt">level</span> change of Society Islands, French Polynesia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Juma Rashid, Rashid; Eisenhauer, Anton; Liebetrau, Volker; Fietzke, Jan; Dullo, Christian; Camoin, Gilbert; Hallmann, Nadine</p> <p>2013-04-01</p> <p>In global average rising eustatic <span class="hlt">sea</span> <span class="hlt">level</span> of several centimeters per decade is predicted for the near future as a consequence of seawater warming and partial melting of the Greenland ice cap (Milne et al., 2009). Beside CO2 induced ocean warming local <span class="hlt">sea-level</span> amplitudes may also vary although no extra water has been added to or extracted from the ocean due to post-glacial geoid reorganization, as a consequence of the emergence of the once glaciated areas and the ocean siphoning effect (Milne et al., 2009; Mitrovica and Peltier, 1991; Mitrovica and Milne, 2002). However, previous research on <span class="hlt">sea</span> <span class="hlt">level</span> change was focused on <span class="hlt">sea-level</span> rise that occurred between the "Last Glacial Maximum, LGM" ~18ka before present (BP) and the so called "Holocene <span class="hlt">Sea</span> <span class="hlt">Level</span> Maximum, HSLM" ~6ka BP. Information about <span class="hlt">sea-level</span> change after the HSLM are rare because the Late Holocene was considered to be climatically stable with minor to negligible <span class="hlt">sea-level</span> oscillations and amplitudes. Here we present U/Th dated fossil corals from conglomerate reef platforms of three islands (Moorea, Huahine and Bora Bora) of the Society Islands, French Polynesia. The fossil coral data constrain the timing and amplitude of <span class="hlt">sea-level</span> variations after the HSLM. We found that <span class="hlt">sea</span> <span class="hlt">level</span> reached a subsidence corrected minimum position of ~1.5±0.2m above present <span class="hlt">sea</span> <span class="hlt">level</span> (apsl) at ~5.4ka. <span class="hlt">Sea</span> <span class="hlt">level</span> then remained at this position with probably minor amplitudinal variations for ~3ka and then dropped to the present position at ~1.9ka. Note, that our study does not provide any data on <span class="hlt">sea-level</span> position from ~1.8ka to the Present. Theoretical predictions (Mitrovica and Milne, 2002) taking the ocean siphoning effect into account predicted a <span class="hlt">sea</span> <span class="hlt">level</span> of ~3m apsl at ~5ka and a constantly decreasing <span class="hlt">sea</span> <span class="hlt">level</span> from 5ka to the present. This is in contrast to our observations indicating a more or less constant <span class="hlt">sea</span> <span class="hlt">level</span> between 5ka and 1.9ka followed by a abrupt drop of <span class="hlt">sea</span> <span class="hlt">level</span> to the present position. Although</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20860690','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20860690"><span>Modeling the transient response of saline intrusion to rising <span class="hlt">sea-levels</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Webb, Matt D; Howard, Ken W F</p> <p>2011-01-01</p> <p><span class="hlt">Sea</span> <span class="hlt">levels</span> are expected to rise as a result of global temperature increases, one implication of which is the potential exacerbation of <span class="hlt">sea</span> water intrusion into coastal aquifers. Given that approximately 70% of the world's population resides in coastal regions, it is imperative to understand the interaction between fresh groundwater and <span class="hlt">sea</span> water intrusion in order to best manage available resources. For this study, controlled investigation has been carried out concerning the temporal variation in <span class="hlt">sea</span> water intrusion as a result of rising <span class="hlt">sea</span> <span class="hlt">levels</span>. A series of fixed inland head two-dimensional <span class="hlt">sea</span> water intrusion models were developed with SEAWAT in order to assess the impact of rising <span class="hlt">sea</span> <span class="hlt">levels</span> on the transient migration of saline intrusion in coastal aquifers under a range of hydrogeological property conditions. A wide range of responses were observed for typical hydrogeological parameter values. Systems with a high ratio of hydraulic conductivity to recharge and high effective porosity lagged behind the equilibrium <span class="hlt">sea</span> water toe positions during <span class="hlt">sea-level</span> rise, often by many hundreds of meters, and frequently taking several centuries to equilibrate following a cease in <span class="hlt">sea-level</span> rise. Systems with a low ratio of hydraulic conductivity to recharge and low effective porosity did not develop such a large degree of disequilibrium and generally stabilized within decades following a cease in <span class="hlt">sea-level</span> rise. This study provides qualitative initial estimates for the expected rate of intrusion and predicted degree of disequilibrium generated by <span class="hlt">sea-level</span> rise for a range of hydrogeological parameter values.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4872146','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4872146"><span>Subtle reproductive impairment through nitric oxide-mediated mechanisms in <span class="hlt">sea</span> urchins from an area <span class="hlt">affected</span> by harmful algal blooms</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Migliaccio, Oriana; Castellano, Immacolata; Di Cioccio, Davide; Tedeschi, Gabriella; Negri, Armando; Cirino, Paola; Romano, Giovanna; Zingone, Adriana; Palumbo, Anna</p> <p>2016-01-01</p> <p>The health of the <span class="hlt">sea</span> urchin Paracentrotus lividus, a key species in the Mediterranean <span class="hlt">Sea</span>, is menaced by several pressures in coastal environments. Here, we aimed at assessing the reproductive ability of apparently healthy P. lividus population in a marine protected area <span class="hlt">affected</span> by toxic blooms of Ostreospsis cf. ovata. Wide-ranging analyses were performed in animals collected prior to and during the bloom, as well as at several times thereafter, during the reproductive season. Adults showed a low fertilization rate, along with high nitric oxide (NO) <span class="hlt">levels</span> in the gonads and the nitration of the major yolk protein toposome, which is an important player in <span class="hlt">sea</span> urchin development. Serious developmental anomalies were observed in the progeny, which persist several months after the bloom. NO <span class="hlt">levels</span> were high in the different developmental stages, which also showed variations in the transcription of several genes that were found to be directly or indirectly modulated by NO. These results highlight subtle but important reproductive flaws transmitted from the female gonads to the offspring with the NO involvement. Despite a recovery along time after the bloom, insidious damages can be envisaged in the local <span class="hlt">sea</span> urchin population, with possible reverberation on the whole benthic system. PMID:27192939</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...626086M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...626086M"><span>Subtle reproductive impairment through nitric oxide-mediated mechanisms in <span class="hlt">sea</span> urchins from an area <span class="hlt">affected</span> by harmful algal blooms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Migliaccio, Oriana; Castellano, Immacolata; di Cioccio, Davide; Tedeschi, Gabriella; Negri, Armando; Cirino, Paola; Romano, Giovanna; Zingone, Adriana; Palumbo, Anna</p> <p>2016-05-01</p> <p>The health of the <span class="hlt">sea</span> urchin Paracentrotus lividus, a key species in the Mediterranean <span class="hlt">Sea</span>, is menaced by several pressures in coastal environments. Here, we aimed at assessing the reproductive ability of apparently healthy P. lividus population in a marine protected area <span class="hlt">affected</span> by toxic blooms of Ostreospsis cf. ovata. Wide-ranging analyses were performed in animals collected prior to and during the bloom, as well as at several times thereafter, during the reproductive season. Adults showed a low fertilization rate, along with high nitric oxide (NO) <span class="hlt">levels</span> in the gonads and the nitration of the major yolk protein toposome, which is an important player in <span class="hlt">sea</span> urchin development. Serious developmental anomalies were observed in the progeny, which persist several months after the bloom. NO <span class="hlt">levels</span> were high in the different developmental stages, which also showed variations in the transcription of several genes that were found to be directly or indirectly modulated by NO. These results highlight subtle but important reproductive flaws transmitted from the female gonads to the offspring with the NO involvement. Despite a recovery along time after the bloom, insidious damages can be envisaged in the local <span class="hlt">sea</span> urchin population, with possible reverberation on the whole benthic system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMPP54A..07H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMPP54A..07H"><span>Drivers of <span class="hlt">sea-level</span> change - using relative <span class="hlt">sea</span> <span class="hlt">level</span> records from the North and South Atlantic to fingerprint sources of mid-Holocene ice melt</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Horton, B.; Khan, N.; Ashe, E.; Kopp, R. E.; Long, A. J.; Gehrels, W. R.</p> <p>2015-12-01</p> <p>Many factors give rise to relative <span class="hlt">sea-level</span> (RSL) changes that are far from globally uniform. For example, spatially variable <span class="hlt">sea-level</span> responses arise because of the exchange of mass between ice sheets and oceans. Gravitational, flexural, and rotational processes generate a distinct spatial pattern - or "fingerprint" - of <span class="hlt">sea-level</span> change associated with each shrinking land ice mass. As a land ice mass shrinks, <span class="hlt">sea-level</span> rise is greater in areas geographically distal to the ice mass than in areas proximal to it, in large part because the gravitational attraction between the ice mass and the ocean is reduced. Thus, the U.S. mid-Atlantic coastline experiences about 50% of the global average <span class="hlt">sea-level</span>-rise due to Greenland Ice Sheet melt, but about 120% of the global average due to West Antarctic Ice Sheet melt. Separating the Greenland and Antarctic ice sheet contributions during the past 7,000 years requires analysis of <span class="hlt">sea-level</span> changes from sites in the northern and southern hemisphere. Accordingly we present <span class="hlt">sea-level</span> records within a hierarchical statistical modeling to: (1) quantify rates of change; (2) compare rates of change among sites, including full quantification of the uncertainty in their differences; and (3) test hypotheses about the sources of meltwater through their <span class="hlt">sea-level</span> fingerprints. Preliminary analysis of three sites within our North and South Atlantic <span class="hlt">sea-level</span> database indicates <span class="hlt">sea-level</span> gradient in the rate of RSL rise during the mid Holocene between 6000 and 4000 years BP; a greater change in rate is found in Brazil than St Croix than New Jersey, consistent with an increase and then decrease in Greenland Ice Sheet mass.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012OcDyn..62..969B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012OcDyn..62..969B"><span>Extracting <span class="hlt">sea</span> <span class="hlt">level</span> residual in tidally dominated estuarine environments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brown, Jennifer M.; Bolaños, Rodolfo; Howarth, Michael J.; Souza, Alejandro J.</p> <p>2012-07-01</p> <p><span class="hlt">Sea</span> <span class="hlt">level</span> comprises a mean <span class="hlt">level</span>, tidal elevation and a residual elevation. Knowledge of what causes maximum water <span class="hlt">levels</span> is often key in coastal management. However, different methods to extract deviations in water <span class="hlt">level</span> (residuals) from modelled and observed elevation can give different results. The Dee Estuary, northwest England is a macrotidal estuary that undergoes periodic stratification. It is used here to demonstrate methods to extract the residual water <span class="hlt">level</span> in response to the following interactive processes: tidal, river-induced stratification and flow, meteorology and waves. Using modelling techniques, the interaction and contribution of different physical processes are investigated. Classical harmonic tidal analysis, model simulations and filtering techniques have been used to "de-tide" the total elevation for short-term (approximately month long) records. Each technique gives a different result highlighting the need to select the correct method for a required study. Analysis of the residual components demonstrates that all processes inducing residuals interact with the tide generating a semi-diurnal residual component. It is suggested that modelling methods enable the full effect of tidal interaction to remain in the residual, whilst harmonic tidal analysis (partly) modify and filtering methods (fully) remove this component of the residual. The analysis methods presented and their influences on the resultant residual are applicable to other study sites. However, when applied specifically to the mouth of the Dee Estuary, the external surge is found to be the main contributor to the total residual, whilst local wind and stratification effects are of secondary importance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992GMS....69..133T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992GMS....69..133T"><span><span class="hlt">Sea</span> <span class="hlt">level</span> variations in the northeast Atlantic from GEOSAT</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tokmakian, R.; Challenor, P. G.</p> <p></p> <p>This paper discusses observations of <span class="hlt">sea</span> <span class="hlt">level</span> in the Northeast Atlantic between 5° and 45° west and 25° and 45° north as measured by GEOSAT. Two years of GEOSAT exact repeal data were collocated on a 0.06 degree grid with the mean <span class="hlt">sea</span> surface removed by the along track difference method. Tthe orbit error was extracted by a crossover analysis technique. The data set was then interpolated with a Successive Correction Method onto 15 day, 0.5 degree maps to produce 47 residual height fields to be analyzed using complex empirical orthogonal functions. The results show that there is a region of high variability in the northwest comer reflecting the Gulf Stream extension and a region of medium variability at approximately 35 degrees north reflecting the Azores Current. The variability changes only slightly throughout the year, with the winter season being the highest. The complex EOFs do not show an annual signal, but do show some wave-like feature of approximately a 225 day period propagating westward.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMPP43A2259J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMPP43A2259J"><span>Influence of <span class="hlt">sea</span> <span class="hlt">level</span> change on sediment provenance variations since the last glaciation in the southern South China <span class="hlt">Sea</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jiwarungrueangkul, T.; Liu, Z.; Zhao, Y.</p> <p>2015-12-01</p> <p>Clay mineralogy and grain size of 170 sediment samples from Core MD05-2893 located near the Molengraaff paleo-river mouth on the upper Sunda slope in the southern South China <span class="hlt">Sea</span> were investigated to assess the effect of <span class="hlt">sea</span> <span class="hlt">level</span> change on sediment provenance variations. The clay mineral results show high contents of smectite (35-55%), moderate contents of illite (16-31%), kaolinite (11-29%), and chlorite (8-15%). Due to distinction of clay mineral assemblages from each sediment provenance, the Indonesian Archipelago is the majority of smectite source, whereas North Boneo mainly provides illite to the southern South China <span class="hlt">Sea</span>. Therefore, the smectite/illite ratio is applied to determine the sediment provenance variations. Both the mineralogical ratio and median grain size show consistent sediment source and dynamic variations since the last glaciation, in which case the response of sediment provenance change due to the <span class="hlt">sea</span> <span class="hlt">level</span> rise is expected. Our study suggests a three-stage evolution of the sediment provenance variation on the Sunda slope in the southern South China <span class="hlt">Sea</span>: (1) during the low <span class="hlt">sea</span> <span class="hlt">level</span> stand of the last glaciation, the high content of smectite implies that the Indonesian Archipelago provided the majority of sediments to this area through the Molengraaff paleo-river system; (2) during the <span class="hlt">sea</span> <span class="hlt">level</span> rise of the deglaciation, the decreasing of smectite content but the increasing of illite indicates that the Indonesian Archipelago reduced in sediments supply due to regression of coastline, whereas North Boneo increased sediment supply; (3) during the high <span class="hlt">sea</span> <span class="hlt">level</span> stand of Holocene, the smectite content increases again, implying that the Indonesian Archipelago provides sediments to this area again through the ocean circulation. Consequently, the <span class="hlt">sea</span> <span class="hlt">level</span> rise mainly results in sediment provenance change in the southern South China <span class="hlt">Sea</span> since the last deglaciation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.C13D..01N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.C13D..01N"><span>Constraining the Antarctic contribution to interglacial <span class="hlt">sea-level</span> rise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Naish, T.; Mckay, R. M.; Barrett, P. J.; Levy, R. H.; Golledge, N. R.; Deconto, R. M.; Horgan, H. J.; Dunbar, G. B.</p> <p>2015-12-01</p> <p>Observations, models and paleoclimate reconstructions suggest that Antarctica's marine-based ice sheets behave in an unstable manner with episodes of rapid retreat in response to warming climate. Understanding the processes involved in this "marine ice sheet instability" is key for improving estimates of Antarctic ice sheet contribution to future <span class="hlt">sea-level</span> rise. Another motivating factor is that far-field <span class="hlt">sea-level</span> reconstructions and ice sheet models imply global mean <span class="hlt">sea</span> <span class="hlt">level</span> (GMSL) was up to 20m and 10m higher, respectively, compared with present day, during the interglacials of the warm Pliocene (~4-3Ma) and Late Pleistocene (at ~400ka and 125ka). This was when atmospheric CO2 was between 280 and 400ppm and global average surface temperatures were 1- 3°C warmer, suggesting polar ice sheets are highly sensitive to relatively modest increases in climate forcing. Such magnitudes of GMSL rise not only require near complete melt of the Greenland Ice Sheet and the West Antarctic Ice Sheet, but a substantial retreat of marine-based sectors of East Antarctic Ice Sheet. Recent geological drilling initiatives on the continental margin of Antarctica from both ship- (e.g. IODP; International Ocean Discovery Program) and ice-based (e.g. ANDRILL/Antarctic Geological Drilling) platforms have provided evidence supporting retreat of marine-based ice. However, without direct access through the ice sheet to archives preserved within sub-glacial sedimentary basins, the volume and extent of ice sheet retreat during past interglacials cannot be directly constrained. Sediment cores have been successfully recovered from beneath ice shelves by the ANDRILL Program and ice streams by the WISSARD (Whillans Ice Stream Sub-glacial Access Research Drilling) Project. Together with the potential of the new RAID (Rapid Access Ice Drill) initiative, these demonstrate the technological feasibility of accessing the subglacial bed and deeper sedimentary archives. In this talk I will outline the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GPC...139....1W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GPC...139....1W"><span>Relative <span class="hlt">sea-level</span> changes during the last century recorded by coral microatolls in Belloc, Haiti</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weil-Accardo, J.; Feuillet, N.; Jacques, E.; Deschamps, P.; Saurel, J.-M.; Thirumalai, K.; Demeza, S.; Anglade, D.</p> <p>2016-04-01</p> <p>We present here the first study of coral microatolls in the Caribbean. An exceptional site (Belloc reef) where dozens of microatolls were growing was uplifted and exposed during the 12 January 2010 Mw 7 Haiti earthquake. Total station measurements of the old pre-earthquake and the new post-earthquake coral highest <span class="hlt">level</span> of survival (HLS) on two generations of Siderastrea siderea corals allowed us to estimate a value of 45 ± 14 cm for the coseismic uplift. In this small 90 m × 70 m reef, microatolls of different shapes (cups, hats or flats) coexist, indicating long term submergence, emergence or stable relative <span class="hlt">sea-level</span>. This variability in coral shape is uncommon. Two slices of microatolls, one cup-shaped (B8) and one hat-shaped (B10) were sampled with a chain saw and X-rayed to study their stratigraphy. B10 recorded a mean relative <span class="hlt">sea-level</span> decrease of about - 1 mm/yr over the last five decades, whereas B8 has grown in a context of relative <span class="hlt">sea-level</span> rise at a rate of about 1 mm/yr over nine decades. Several sudden and temporary die downs simultaneously disrupted the growth of both corals in 1940 ± 2, 1963 ± 2, 1983 ± 2, 1992 ± 1, 2001 ± 1 and 2009 and may be caused by oceanographic/climatic phenomena occurring in the tropical North Atlantic. The last one, in 2009, was associated with a clear <span class="hlt">sea-level</span> height decrease (about 10 cm) in the satellite data. B10 was strongly <span class="hlt">affected</span> by these events and records die downs of systematically larger amplitude, which tended to delay its upward growth compared to B8. This makes B10 less reliable for the evaluation of the relative <span class="hlt">sea-level</span> trend, its emergence rate being only an apparent estimate due to die downs. Fossil coral microatolls of Diploria strigosa which died between 1958 and 1966 (according to U/Th dating), probably during one of the strongest hurricane reported in Haiti (Flora, 1963), display a cup shape attesting for submergence. Their HLS is 1 cm below the HLS of the S. siderea killed in 2010. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26460051','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26460051"><span>Carbon choices determine US cities committed to futures below <span class="hlt">sea</span> <span class="hlt">level</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Strauss, Benjamin H; Kulp, Scott; Levermann, Anders</p> <p>2015-11-03</p> <p>Anthropogenic carbon emissions lock in long-term <span class="hlt">sea-level</span> rise that greatly exceeds projections for this century, posing profound challenges for coastal development and cultural legacies. Analysis based on previously published relationships linking emissions to warming and warming to rise indicates that unabated carbon emissions up to the year 2100 would commit an eventual global <span class="hlt">sea-level</span> rise of 4.3-9.9 m. Based on detailed topographic and population data, local high tide lines, and regional long-term <span class="hlt">sea-level</span> commitment for different carbon emissions and ice sheet stability scenarios, we compute the current population living on endangered land at municipal, state, and national <span class="hlt">levels</span> within the United States. For unabated climate change, we find that land that is home to more than 20 million people is implicated and is widely distributed among different states and coasts. The total area includes 1,185-1,825 municipalities where land that is home to more than half of the current population would be <span class="hlt">affected</span>, among them at least 21 cities exceeding 100,000 residents. Under aggressive carbon cuts, more than half of these municipalities would avoid this commitment if the West Antarctic Ice Sheet remains stable. Similarly, more than half of the US population-weighted area under threat could be spared. We provide lists of implicated cities and state populations for different emissions scenarios and with and without a certain collapse of the West Antarctic Ice Sheet. Although past anthropogenic emissions already have caused <span class="hlt">sea-level</span> commitment that will force coastal cities to adapt, future emissions will determine which areas we can continue to occupy or may have to abandon.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6470553','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6470553"><span>Vegetation change on a northeast tidal marsh: Interaction of <span class="hlt">sea-level</span> rise and marsh accretion</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Warren, R.S.; Niering, W.A. )</p> <p>1993-01-01</p> <p>Increasing rates of relative <span class="hlt">sea-level</span> rise (RSL) have been linked to coastal wetland losses along the Gulf of Mexico and elsewhere. Rapidly rising RSL may be <span class="hlt">affecting</span> New England tidal marshes. Studies of the Wequetequock-Pawcatuck tidal marshes over four decades have documented dramatic changes in vegetation apparently related primarily to differential rates of marsh accretion and <span class="hlt">sea-level</span> rise though sediment supply and anthropogenic modifications of the system may also be involved. When initially studied in 1947-1948 the high marsh supported a Juncus gerardi-Spartina patens belting pattern typical of many New England salt marshes. On most of the marsh complex the former Juncus belt has now been replaced by forbs, primarily Triglochin maritima, while the former S. patens high marsh is now a complex of vegetation types-stunted Spartina alterniflora, Distichlis spicata, forbs, and relic stands of S. patens. The mean surface elevation of areas where the vegetation has changed is significantly lower than that of areas still supporting the earlier pattern (4.6 vs. 13.9 cm above mean tide <span class="hlt">level</span>). The differences in surface elevation reflect differences in accretion of marsh peat. Stable areas have been accreting at the rate of local <span class="hlt">sea-level</span> rise, 2.0-2.5 mm/yr at least since 1938; changed areas have accreted at about one half that rate. Lower surface elevations result in greater frequency and duration of tidal flooding, and thus in increased peat saturation, salinity, and sulfide concentrations, and in decreased redox potential, as directly measured over the growing season at both changed and stable sites. These edaphic changes may have combined to favor establishment of a wetter, more open vegetation type. Similar changes have been observed on other Long Island Sound marshes and may be a model for the potential effects of <span class="hlt">sea-level</span> rise on New England tidal salt marshes. 39 refs., 4 figs., 1 tab.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4640796','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4640796"><span>Carbon choices determine US cities committed to futures below <span class="hlt">sea</span> <span class="hlt">level</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Strauss, Benjamin H.; Kulp, Scott; Levermann, Anders</p> <p>2015-01-01</p> <p>Anthropogenic carbon emissions lock in long-term <span class="hlt">sea-level</span> rise that greatly exceeds projections for this century, posing profound challenges for coastal development and cultural legacies. Analysis based on previously published relationships linking emissions to warming and warming to rise indicates that unabated carbon emissions up to the year 2100 would commit an eventual global <span class="hlt">sea-level</span> rise of 4.3–9.9 m. Based on detailed topographic and population data, local high tide lines, and regional long-term <span class="hlt">sea-level</span> commitment for different carbon emissions and ice sheet stability scenarios, we compute the current population living on endangered land at municipal, state, and national <span class="hlt">levels</span> within the United States. For unabated climate change, we find that land that is home to more than 20 million people is implicated and is widely distributed among different states and coasts. The total area includes 1,185–1,825 municipalities where land that is home to more than half of the current population would be <span class="hlt">affected</span>, among them at least 21 cities exceeding 100,000 residents. Under aggressive carbon cuts, more than half of these municipalities would avoid this commitment if the West Antarctic Ice Sheet remains stable. Similarly, more than half of the US population-weighted area under threat could be spared. We provide lists of implicated cities and state populations for different emissions scenarios and with and without a certain collapse of the West Antarctic Ice Sheet. Although past anthropogenic emissions already have caused <span class="hlt">sea-level</span> commitment that will force coastal cities to adapt, future emissions will determine which areas we can continue to occupy or may have to abandon. PMID:26460051</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016OSJ....51...87M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016OSJ....51...87M"><span>Shifts in multi-decadal <span class="hlt">sea</span> <span class="hlt">level</span> trends in the East/Japan <span class="hlt">Sea</span> over the past 60 years</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moon, Jae-Hong; Lee, Joonho</p> <p>2016-03-01</p> <p>Data derived from altimetry shows that since 1993 the mean <span class="hlt">sea</span> <span class="hlt">level</span> over the East /Japan (EJS) <span class="hlt">Sea</span> is increasing at a rate of ~3 mm/year, but tide gauge records indicate that a multidecadal reversal trend occurred prior to the early 1980s. We here characterize and quantify the multi-decadal trend of mean <span class="hlt">sea</span> <span class="hlt">level</span> in the EJS from the reconstructed <span class="hlt">sea</span> <span class="hlt">levels</span> and the in-situ ocean profiles over the past 60 years. Our analysis shows that <span class="hlt">sea</span> <span class="hlt">level</span> trends have undergone a shift, revealing a declining trend before the early 1980s, followed by a rising trend from the early 1980s onward with a near basin-wide <span class="hlt">sea</span> <span class="hlt">level</span> fluctuation. The trend reversal strongly corresponds to changes in the upper-ocean heat content over the EJS, revealing a negative correlation with the Pacific Decadal Oscillation (PDO) index that correlates negatively with wind stress curl (WSC) in the subtropical North Pacific. The PDO-related WSC, which changes the transport of the western boundary current in the subtropical gyre, may account for the observed trend reversal in the EJS <span class="hlt">sea</span> <span class="hlt">level</span> on a multi-decadal time scale.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1812775D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1812775D"><span>Quantitative analysis of Paratethys <span class="hlt">sea</span> <span class="hlt">level</span> change during the Messinian Salinity Crisis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>de la Vara, Alba; Meijer, Paul; van Baak, Christiaan; Marzocchi, Alice; Grothe, Arjen</p> <p>2016-04-01</p> <p>At the time of the Messinian Salinity Crisis in the Mediterranean <span class="hlt">Sea</span> (i.e., the Pontian stage of the Paratethys), the Paratethys <span class="hlt">sea</span> <span class="hlt">level</span> dropped also. Evidence found in the sedimentary record of the Black <span class="hlt">Sea</span> and the Caspian <span class="hlt">Sea</span> has been interpreted to indicate that a <span class="hlt">sea</span> <span class="hlt">level</span> fall occurred between 5.6 and 5.5 Ma. Estimates for the magnitude of the fall range between tens of meters to more than 1500 m. The purpose of this study is to provide quantitative insight into the sensitivity of the water <span class="hlt">level</span> of the Black <span class="hlt">Sea</span> and the Caspian <span class="hlt">Sea</span> to the hydrologic budget, for the case that the Paratethys is disconnected from the Mediterranean. Using a Late Miocene bathymetry based on a palaeographic map by Popov et al. (2004) we quantify the fall in <span class="hlt">sea</span> <span class="hlt">level</span>, the mean salinity, and the time to reach equilibrium for a wide range of negative hydrologic budgets. By combining our results with (i) estimates derived from a recent global Late Miocene climate simulation and (ii) reconstructed basin salinities, we are able to rule out a drop in <span class="hlt">sea</span> <span class="hlt">level</span> of the order of 1000 m in the Caspian <span class="hlt">Sea</span> during this time period. In the Black <span class="hlt">Sea</span>, however, such a large <span class="hlt">sea</span> <span class="hlt">level</span> fall cannot be fully discarded.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26306559','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26306559"><span>Dietary carbohydrate and lipid source <span class="hlt">affect</span> cholesterol metabolism of European <span class="hlt">sea</span> bass (Dicentrarchus labrax) juveniles.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Castro, Carolina; Corraze, Geneviève; Pérez-Jiménez, Amalia; Larroquet, Laurence; Cluzeaud, Marianne; Panserat, Stéphane; Oliva-Teles, Aires</p> <p>2015-10-28</p> <p>Plant feedstuffs (PF) are rich in carbohydrates, which may interact with lipid metabolism. Thus, when considering dietary replacement of fishery by-products with PF, knowledge is needed on how dietary lipid source (LS) and carbohydrates <span class="hlt">affect</span> lipid metabolism and other metabolic pathways. For that purpose, a 73-d growth trial was performed with European <span class="hlt">sea</span> bass juveniles (IBW 74 g) fed four diets differing in LS (fish oil (FO) or a blend of vegetable oils (VO)) and carbohydrate content (0 % (CH-) or 20 % (CH+) gelatinised starch). At the end of the trial no differences among diets were observed on growth and feed utilisation. Protein efficiency ratio was, however, higher in the CH+ groups. Muscle and liver fatty acid profiles reflected the dietary LS. Dietary carbohydrate promoted higher plasma cholesterol and phospholipids (PL), whole-body and hepatic (mainly 16 : 0) lipids and increased muscular and hepatic glycogen. Except for PL, which were higher in the FO groups, no major alterations between FO and VO groups were observed on plasma metabolites (glucose, TAG, cholesterol, PL), liver and muscle glycogen, and lipid and cholesterol contents. Activities of glucose-6-phosphate dehydrogenase and malic enzyme - lipogenesis-related enzymes - increased with carbohydrate intake. Hepatic expression of genes involved in cholesterol metabolism was up-regulated with carbohydrate (HMGCR and CYP3A27) and VO (HMGCR and CYP51A1) intake. No dietary regulation of long-chain PUFA biosynthesis at the transcriptional <span class="hlt">level</span> was observed. Overall, very few interactions between dietary carbohydrates and LS were observed. However, important insights on the direct relation between dietary carbohydrate and the cholesterol biosynthetic pathway in European <span class="hlt">sea</span> bass were demonstrated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1995CSR....15..981B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1995CSR....15..981B"><span>Long-term <span class="hlt">sea-level</span> variations in the central Great Barrier Reef</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Burrage, Derek M.; Black, Kerry P.; Steinberg, Craig R.</p> <p>1995-07-01</p> <p>Low frequency <span class="hlt">sea-level</span> variations and associated geostrophic currents in the central Great Barrier Reef (GBR) region near Townsville are studied using optimally-lagged multivariate regression. The analyses show that pressure-adjusted coastal <span class="hlt">sea</span> <span class="hlt">levels</span> and mid-shelf geostrophic currents are influenced predominantly by local along-shelf wind stress at the weather time-scale, and by climatic variables, such as atmospheric pressure and temperature, at seasonal and inter-annual time-scales. These forcing variables can specify <span class="hlt">sea</span> <span class="hlt">levels</span> over annual and inter-annual time-scales with a forecasting skill of 0.53 and 0.22, respectively (where 1.0 is perfect skill). Associated along-shelf geostrophic currents can be forecast with a skill of 0.57 over an annual time scale. If, instead, absolute coastal <span class="hlt">sea</span> <span class="hlt">levels</span> or offshore <span class="hlt">sea-level</span> differences are used to specify the along-shelf geostrophic current, the forecasting skill is 0.75. A characteristic El Niño/Southern Oscillation (ENSO) response is detected for time periods up to 25 years in monthly <span class="hlt">sea-level</span> both at Townsville and at western Pacific island <span class="hlt">sea-level</span> stations. This spatially coherent response varies in intensity and phase within the Coral <span class="hlt">Sea</span>. <span class="hlt">Sea-level</span> differences show a pattern which characterizes known features of the large-scale circulation of the Coral <span class="hlt">Sea</span>. These very low frequency <span class="hlt">sea-level</span> variations in the Coral <span class="hlt">Sea</span> must be taken into account to obtain accurate predictions of along-shelf geostrophic current variations on seasonal and inter-annual time scales. Regression analysis and a diagnostic river plume model show that the influence of the major rivers can produce <span class="hlt">sea-level</span> changes due to buoyancy of order 5 cm. The corresponding errors in geostrophic velocities estimated using pressure-adjusted Townsville <span class="hlt">sea-level</span> data alone are of order 5 cm s -1 rms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5216410','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5216410"><span><span class="hlt">Sea-level</span> rise induced amplification of coastal protection design heights</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Arns, Arne; Dangendorf , Sönke; Jensen, Jürgen; Talke, Stefan; Bender, Jens; Pattiaratchi, Charitha</p> <p>2017-01-01</p> <p>Coastal protection design heights typically consider the superimposed effects of tides, surges, waves, and relative <span class="hlt">sea-level</span> rise (SLR), neglecting non-linear feedbacks between these forcing factors. Here, we use hydrodynamic modelling and multivariate statistics to show that shallow coastal areas are extremely sensitive to changing non-linear interactions between individual components caused by SLR. As <span class="hlt">sea-level</span> increases, the depth-limitation of waves relaxes, resulting in waves with larger periods, greater amplitudes, and higher run-up; moreover, depth and frictional changes <span class="hlt">affect</span> tide, surge, and wave characteristics, altering the relative importance of other risk factors. Consequently, <span class="hlt">sea-level</span> driven changes in wave characteristics, and to a lesser extent, tides, amplify the resulting design heights by an average of 48–56%, relative to design changes caused by SLR alone. Since many of the world’s most vulnerable coastlines are impacted by depth-limited waves, our results suggest that the overall influence of SLR may be greatly underestimated in many regions. PMID:28057920</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28057920','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28057920"><span><span class="hlt">Sea-level</span> rise induced amplification of coastal protection design heights.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Arns, Arne; Dangendorf, Sönke; Jensen, Jürgen; Talke, Stefan; Bender, Jens; Pattiaratchi, Charitha</p> <p>2017-01-06</p> <p>Coastal protection design heights typically consider the superimposed effects of tides, surges, waves, and relative <span class="hlt">sea-level</span> rise (SLR), neglecting non-linear feedbacks between these forcing factors. Here, we use hydrodynamic modelling and multivariate statistics to show that shallow coastal areas are extremely sensitive to changing non-linear interactions between individual components caused by SLR. As <span class="hlt">sea-level</span> increases, the depth-limitation of waves relaxes, resulting in waves with larger periods, greater amplitudes, and higher run-up; moreover, depth and frictional changes <span class="hlt">affect</span> tide, surge, and wave characteristics, altering the relative importance of other risk factors. Consequently, <span class="hlt">sea-level</span> driven changes in wave characteristics, and to a lesser extent, tides, amplify the resulting design heights by an average of 48-56%, relative to design changes caused by SLR alone. Since many of the world's most vulnerable coastlines are impacted by depth-limited waves, our results suggest that the overall influence of SLR may be greatly underestimated in many regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NatSR...740171A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NatSR...740171A"><span><span class="hlt">Sea-level</span> rise induced amplification of coastal protection design heights</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arns, Arne; Dangendorf, Sönke; Jensen, Jürgen; Talke, Stefan; Bender, Jens; Pattiaratchi, Charitha</p> <p>2017-01-01</p> <p>Coastal protection design heights typically consider the superimposed effects of tides, surges, waves, and relative <span class="hlt">sea-level</span> rise (SLR), neglecting non-linear feedbacks between these forcing factors. Here, we use hydrodynamic modelling and multivariate statistics to show that shallow coastal areas are extremely sensitive to changing non-linear interactions between individual components caused by SLR. As <span class="hlt">sea-level</span> increases, the depth-limitation of waves relaxes, resulting in waves with larger periods, greater amplitudes, and higher run-up; moreover, depth and frictional changes <span class="hlt">affect</span> tide, surge, and wave characteristics, altering the relative importance of other risk factors. Consequently, <span class="hlt">sea-level</span> driven changes in wave characteristics, and to a lesser extent, tides, amplify the resulting design heights by an average of 48–56%, relative to design changes caused by SLR alone. Since many of the world’s most vulnerable coastlines are impacted by depth-limited waves, our results suggest that the overall influence of SLR may be greatly underestimated in many regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/9298550','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/9298550"><span>Physiological implications of altitude training for endurance performance at <span class="hlt">sea</span> <span class="hlt">level</span>: a review.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bailey, D M; Davies, B</p> <p>1997-09-01</p> <p> training and accelerate performance improvements after return to <span class="hlt">sea</span> <span class="hlt">level</span>. This has stimulated an exponential increase in scientific research, and, since 1984, 22 major reviews have summarised the physiological implications of altitude training for both aerobic and anaerobic performance at altitude and after return to <span class="hlt">sea</span> <span class="hlt">level</span>. Of these reviews, only eight have specifically focused on physical performance changes after return to <span class="hlt">sea</span> <span class="hlt">level</span>, the most comprehensive of which was recently written by Wolski et al. Few reviews have considered the potentially less favourable physiological responses to moderate altitude exposure, which include decreases in absolute training intensity, decreased plasma volume, depression of haemopoiesis and increased haemolysis, increases in sympathetically mediated glycogen depletion at altitude, and increased respiratory muscle work after return to <span class="hlt">sea</span> <span class="hlt">level</span>. In addition, there is a risk of developing more serious medical complications at altitude, which include acute mountain sickness, pulmonary oedema, cardiac arrhythmias, and cerebral hypoxia. The possible implications of changes in immune function at altitude have also been largely ignored, despite accumulating evidence of hypoxia mediated immunosuppression. In general, altitude training has been shown to improve performance at altitude, whereas no unequivocal evidence exists to support the claim that performance at <span class="hlt">sea</span> <span class="hlt">level</span> is improved. Table 1 summarises the theoretical advantages and disadvantages of altitude training for <span class="hlt">sea</span> <span class="hlt">level</span> performance. This review summarises the physiological rationale for altitude training as a means of enhancing endurance performance after return to <span class="hlt">sea</span> <span class="hlt">level</span>. Factors that have been shown to <span class="hlt">affect</span> the acclimatisation process and the subsequent implications for exercise performance at <span class="hlt">sea</span> <span class="hlt">level</span> will also be discussed. Studies were located using five major database searches, which included Medline, Embase, Science Citation Index, Sports Discus, and Sport, in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18339903','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18339903"><span>Impact of artificial reservoir water impoundment on global <span class="hlt">sea</span> <span class="hlt">level</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chao, B F; Wu, Y H; Li, Y S</p> <p>2008-04-11</p> <p>By reconstructing the history of water impoundment in the world's artificial reservoirs, we show that a total of approximately 10,800 cubic kilometers of water has been impounded on land to date, reducing the magnitude of global <span class="hlt">sea</span> <span class="hlt">level</span> (GSL) rise by -30.0 millimeters, at an average rate of -0.55 millimeters per year during the past half century. This demands a considerably larger contribution to GSL rise from other (natural and anthropogenic) causes than otherwise required. The reconstructed GSL history, accounting for the impact of reservoirs by adding back the impounded water volume, shows an essentially constant rate of rise at +2.46 millimeters per year over at least the past 80 years. This value is contrary to the conventional view of apparently variable GSL rise, which is based on face values of observation.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.U13A..01H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.U13A..01H"><span>Scientific Reticence and <span class="hlt">Sea</span> <span class="hlt">Level</span> Rise (Invited Talk)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hansen, J. E.</p> <p>2015-12-01</p> <p>Caution is an essential ingredient in scientific investigations, as success in science depends on objective skepticism. In some cases a cultural resistance to scientific discovery has seemed to exist and there are other factors that can contribute to scientific reticence. In a case such as ice sheet instability and <span class="hlt">sea</span> <span class="hlt">level</span> rise there is a danger that excessive caution might serve to lock in future disasters. I discussed these issues almost a decade ago (in Environ. Res. Lett., 2, 024002, 2007, doi:10.1088/1748-9326/2/2/024002), but given all that has transpired since then, this topic has become even more relevant and urgent. I will discuss the status of this dilemma as I see it.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.1296T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.1296T"><span><span class="hlt">Sea</span> <span class="hlt">Level</span> Rise as Covariate for Extreme Value Analysis and Forecasting at the Operational <span class="hlt">Level</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Toilliez, Jean; Fay, Segolene</p> <p>2013-04-01</p> <p>An exploration of the performance of time-dependent extreme value models to predict the return <span class="hlt">levels</span> and periods of water <span class="hlt">levels</span> (WL) is presented. The study compares the long-term projections for design water <span class="hlt">levels</span> obtained from a stationary and time-dependent generalized extreme-value distributions (GEVD and GEVDT, resp.). Data is extracted from 12 NOAA coastal locations in the continental United States and consists in mean <span class="hlt">sea-level</span> (MSL) and monthly highest water <span class="hlt">levels</span>. In this context, the usefulness of a time-dependent extreme value model holds in its ability to capture a mean long-term trend and change in variance in the signal. As such, this effort continues on the results obtained by Menendez (2009), who focused on inter-annual variability, and others. By integrating a local or global <span class="hlt">sea-level</span> trend (SLT) as a covariate or as a linear component, the study seeks to establish the engineering value of a time-dependent model over the more frequently used stationary GEVD, ranking and least square fitting methods. In this particular context, we show that in a majority of cases, to date and according to this method, there does not appear to be a sufficient amount of information recorded by tidal gauges to observe and capture a significant amount of variability in the signal. Therefore, in most cases, we show that the linear superimposition of return <span class="hlt">levels</span> with a given offset due to a change in base <span class="hlt">sea-level</span> appears to be a valid method to estimate long-term, future design water <span class="hlt">levels</span>. Nonetheless, the results of this historical data assessment indicate that in some instances, a significant <span class="hlt">level</span> of variability in the frequency or magnitude of extremes is observed. In that case, the difference made between a linear model and a time-dependent can become significant over the long-term, and a time-dependent model is superior. A range of SLT projections are explored based on US Federal and International guidelines. This effort focuses on the application of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1991JGR....96.6727L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1991JGR....96.6727L"><span>Atoll stratigraphy as a record of <span class="hlt">sea</span> <span class="hlt">level</span> change: Problems and prospects</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lincoln, Jonathan M.; Schlanger, Seymour O.</p> <p>1991-04-01</p> <p>Stratigraphic hiatuses and solution unconformities in the subsurface of Enewetak Atoll, northern Marshall Islands, record periods of atoll emergence during low stands of <span class="hlt">sea</span> <span class="hlt">level</span>. Changes in <span class="hlt">sea</span> <span class="hlt">level</span> are also recorded in the atoll subsurface by variations in the rate of sediment accumulation relative to the subsidence rate of the underlying volcanic edifice. Past <span class="hlt">sea</span> <span class="hlt">levels</span> can be derived from atoll stratigraphy by correcting the present depth of dated subsurface horizons for thermal subsidence and lithospheric flexure since the time of deposition. A correction for depositional paleodepth may also be necessary. As a result of erosion and nondeposition during periods of emergence, the history of <span class="hlt">sea</span> <span class="hlt">level</span> derived in this manner is discontinuous. Past <span class="hlt">sea</span> <span class="hlt">levels</span> derived from atoll stratigraphy can only be estimated to within ±50 m relative to present <span class="hlt">sea</span> <span class="hlt">level</span> owing to uncertainties in the corrections for subsidence and flexure; however, the minimum magnitude of <span class="hlt">sea</span> <span class="hlt">level</span> falls estimated from stratigraphic hiatuses can be estimated to within ±10 m. Owing to limited fossil-based age resolution, only long-term <span class="hlt">sea</span> <span class="hlt">level</span> trends can be deduced from sediments dated by means of biostratigraphy. Based on the biostratigraphic ages of subsurface horizons at Enewetak, we can discern very little long-term change in <span class="hlt">sea</span> <span class="hlt">level</span> from late Eocene through late Oligocene, a rise to ˜110 m above present <span class="hlt">sea</span> <span class="hlt">level</span> in the early Miocene, a long-term fall of ˜170 m through middle and late Miocene time, and a long-term rise of ˜60 m from the end of the Miocene to present. Resolution of the <span class="hlt">sea</span> <span class="hlt">level</span> history recorded beneath mid-ocean atolls may be improved by determining the age of shallow-marine carbonates by means of strontium isotope stratigraphy. Our interpretation of past <span class="hlt">sea</span> <span class="hlt">levels</span> based on 87Sr/86Sr chronostratigraphy from Enewetak confirms the long-term <span class="hlt">sea</span> <span class="hlt">level</span> trends inferred from biostratigraphic subsurface ages. In addition, we interpret three Oligocene <span class="hlt">sea</span> <span class="hlt">level</span> falls</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.4175B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.4175B"><span>Postglacial <span class="hlt">sea-level</span> rise and its impact on the circum-arctic Holocene climate evolution</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bauch, Henning; Abramova, Ekaterina; Alenius, Teija; Saarnisto, Matti</p> <p>2016-04-01</p> <p>The global <span class="hlt">sea-level</span> rise after the last glaciation not only <span class="hlt">affected</span> the surface properties (circulation, T-S, <span class="hlt">sea</span> ice seasonality) of the Arctic Ocean and nearby <span class="hlt">seas</span> it also had a strong impact on the Holocene development of the shallow North Siberian shelf systems and the environmental evolution of the adjacent hinterland areas. In this region <span class="hlt">sea</span> <span class="hlt">level</span> reconstructions indicate the postglacial highstand occurred some time in the middle Holocene, between 6 to 5 ka (Klemann et al., 2015). After that time the sedimentary regime of the shelf <span class="hlt">seas</span> stabilized as noted in a drastic decrease in sedimentation rates observed in all sediment cores taken from middle to outer shelf water depths of the Laptev <span class="hlt">Sea</span> (Bauch et al. 2001). But, at water depths lower than 30 meters - i.e., in the inner shelf and nearer to the coasts - sedimentation continued at relatively higher rates, presumably due to input of terrigenous material from river runoff as well as coastal erosion. In relation to the latter process, the huge Lena Delta should comprise a region of sediment catchment where aggradation wins over erosion. However, little is known about the detailed history of this delta during the second half of the Holocene. We therefore have investigated three islands within the Lena Delta. All of these are comprised of massive peat of several meters in thickness. Picking discrete specimens of water mosses (Sphagnum) only, we have carefully dated these peat sections. The depth/age relation of the sampled profiles reflect the growth rate of peat, and thus, the islands. It shows that the islands' history above the present-day delta <span class="hlt">sea</span> <span class="hlt">level</span> is about 4000 yrs. old. Moreover, a significant change in peat growth is noted after 2500 yrs BP in both, accumulation and composition, and allows the conclusion of a major shift in Arctic environmental conditions since then. Thus, our results add further information also for other coastal studies, as the ongoing degradation of the rather vulnerable</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3785813','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3785813"><span>Climate sensitivity, <span class="hlt">sea</span> <span class="hlt">level</span> and atmospheric carbon dioxide</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hansen, James; Sato, Makiko; Russell, Gary; Kharecha, Pushker</p> <p>2013-01-01</p> <p>Cenozoic temperature, <span class="hlt">sea</span> <span class="hlt">level</span> and CO2 covariations provide insights into climate sensitivity to external forcings and <span class="hlt">sea-level</span> sensitivity to climate change. Climate sensitivity depends on the initial climate state, but potentially can be accurately inferred from precise palaeoclimate data. Pleistocene climate oscillations yield a fast-feedback climate sensitivity of 3±1°C for a 4 W m−2 CO2 forcing if Holocene warming relative to the Last Glacial Maximum (LGM) is used as calibration, but the error (uncertainty) is substantial and partly subjective because of poorly defined LGM global temperature and possible human influences in the Holocene. Glacial-to-interglacial climate change leading to the prior (Eemian) interglacial is less ambiguous and implies a sensitivity in the upper part of the above range, i.e. 3–4°C for a 4 W m−2 CO2 forcing. Slow feedbacks, especially change of ice sheet size and atmospheric CO2, amplify the total Earth system sensitivity by an amount that depends on the time scale considered. Ice sheet response time is poorly defined, but we show that the slow response and hysteresis in prevailing ice sheet models are exaggerated. We use a global model, simplified to essential processes, to investigate state dependence of climate sensitivity, finding an increased sensitivity towards warmer climates, as low cloud cover is diminished and increased water vapour elevates the tropopause. Burning all fossil fuels, we conclude, would make most of the planet uninhabitable by humans, thus calling into question strategies that emphasize adaptation to climate change. PMID:24043864</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140017102','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140017102"><span>Climate Sensitivity, <span class="hlt">Sea</span> <span class="hlt">Level</span>, and Atmospheric Carbon Dioxide</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hansen, James; Sato, Makiko; Russell, Gary; Kharecha, Pushker</p> <p>2013-01-01</p> <p>Cenozoic temperature, <span class="hlt">sea</span> <span class="hlt">level</span> and CO2 covariations provide insights into climate sensitivity to external forcings and <span class="hlt">sea-level</span> sensitivity to climate change. Climate sensitivity depends on the initial climate state, but potentially can be accurately inferred from precise palaeoclimate data. Pleistocene climate oscillations yield a fast-feedback climate sensitivity of 3+/-1deg C for a 4 W/sq m CO2 forcing if Holocene warming relative to the Last Glacial Maximum (LGM) is used as calibration, but the error (uncertainty) is substantial and partly subjective because of poorly defined LGM global temperature and possible human influences in the Holocene. Glacial-to-interglacial climate change leading to the prior (Eemian) interglacial is less ambiguous and implies a sensitivity in the upper part of the above range, i.e. 3-4deg C for a 4 W/sq m CO2 forcing. Slow feedbacks, especially change of ice sheet size and atmospheric CO2, amplify the total Earth system sensitivity by an amount that depends on the time scale considered. Ice sheet response time is poorly defined, but we show that the slow response and hysteresis in prevailing ice sheet models are exaggerated. We use a global model, simplified to essential processes, to investigate state dependence of climate sensitivity, finding an increased sensitivity towards warmer climates, as low cloud cover is diminished and increased water vapour elevates the tropopause. Burning all fossil fuels, we conclude, would make most of the planet uninhabitable by humans, thus calling into question strategies that emphasize adaptation to climate change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMOS11A1982D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMOS11A1982D"><span>Anomalies Thermosteric and Halosteric Contributions to <span class="hlt">Sea</span> <span class="hlt">Level</span> Variation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>da Silva, C. E.; Polito, P. S.</p> <p>2015-12-01</p> <p><span class="hlt">Sea</span> <span class="hlt">level</span> anomaly (SLA) is an important indicator of changes in the Earth's climate system because the oceans have great heat storage capacity. The <span class="hlt">sea</span> <span class="hlt">level</span> variation is due to combination of thermosteric and halosteric effects. These two effects play significant roles in the annual cycle of the SLA and maintain the thermohaline circulation. Previous studies only considered the thermosteric effect. The main goal of this study was to determine the regions of the global ocean where the variability induced by halosteric effect is equal or higher than that induced by thermosteric effect. We used temperature and salinity data from World Ocean Atlas 2013 (WOA13) with spatial resolution of 1°x1° during the period of 1955 to 2012 to calculate the coefficient of thermal expansion (α), haline contraction (β) and to estimate their contributions to the SLA variation in the global ocean. Our results showed that the thermosteric effect is dominant in the tropical and subtropical regions due to high insolation throughout the year. However, in polar regions, North Atlantic and North Pacific oceans the halosteric effect was the main contributor to SLA variation. In polar regions, the effect occurs because of the lack in temperature variation and the fact that in this region the precipitation rate exceeds evaporation increasing the freshwater input. In the others, the mechanism is still unknown. The linear trend of thermosteric and halosteric components for 1955-2012 is 0.35mm/yr and 0.07mm/yr, respectively. This results shows that halosteric effect should be considered in the heat storage estimation from satellite data, in situ data and numerical modelling contrasting the previous approaches to SLA.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24043864','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24043864"><span>Climate sensitivity, <span class="hlt">sea</span> <span class="hlt">level</span> and atmospheric carbon dioxide.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hansen, James; Sato, Makiko; Russell, Gary; Kharecha, Pushker</p> <p>2013-10-28</p> <p>Cenozoic temperature, <span class="hlt">sea</span> <span class="hlt">level</span> and CO2 covariations provide insights into climate sensitivity to external forcings and <span class="hlt">sea-level</span> sensitivity to climate change. Climate sensitivity depends on the initial climate state, but potentially can be accurately inferred from precise palaeoclimate data. Pleistocene climate oscillations yield a fast-feedback climate sensitivity of 3±1(°)C for a 4 W m(-2) CO2 forcing if Holocene warming relative to the Last Glacial Maximum (LGM) is used as calibration, but the error (uncertainty) is substantial and partly subjective because of poorly defined LGM global temperature and possible human influences in the Holocene. Glacial-to-interglacial climate change leading to the prior (Eemian) interglacial is less ambiguous and implies a sensitivity in the upper part of the above range, i.e. 3-4(°)C for a 4 W m(-2) CO2 forcing. Slow feedbacks, especially change of ice sheet size and atmospheric CO2, amplify the total Earth system sensitivity by an amount that depends on the time scale considered. Ice sheet response time is poorly defined, but we show that the slow response and hysteresis in prevailing ice sheet models are exaggerated. We use a global model, simplified to essential processes, to investigate state dependence of climate sensitivity, finding an increased sensitivity towards warmer climates, as low cloud cover is diminished and increased water vapour elevates the tropopause. Burning all fossil fuels, we conclude, would make most of the planet uninhabitable by humans, thus calling into question strategies that emphasize adaptation to climate change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.bioone.org/doi/abs/10.2112/SI63-016.1','USGSPUBS'); return false;" href="http://www.bioone.org/doi/abs/10.2112/SI63-016.1"><span>Consideration of vertical uncertainty in elevation-based <span class="hlt">sea-level</span> rise assessments: Mobile Bay, Alabama case study</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Gesch, Dean B.</p> <p>2013-01-01</p> <p>The accuracy with which coastal topography has been mapped directly <span class="hlt">affects</span> the reliability and usefulness of elevationbased <span class="hlt">sea-level</span> rise vulnerability assessments. Recent research has shown that the qualities of the elevation data must be well understood to properly model potential impacts. The cumulative vertical uncertainty has contributions from elevation data error, water <span class="hlt">level</span> data uncertainties, and vertical datum and transformation uncertainties. The concepts of minimum sealevel rise increment and minimum planning timeline, important parameters for an elevation-based <span class="hlt">sea-level</span> rise assessment, are used in recognition of the inherent vertical uncertainty of the underlying data. These concepts were applied to conduct a <span class="hlt">sea-level</span> rise vulnerability assessment of the Mobile Bay, Alabama, region based on high-quality lidar-derived elevation data. The results that detail the area and associated resources (land cover, population, and infrastructure) vulnerable to a 1.18-m <span class="hlt">sea-level</span> rise by the year 2100 are reported as a range of values (at the 95% confidence <span class="hlt">level</span>) to account for the vertical uncertainty in the base data. Examination of the tabulated statistics about land cover, population, and infrastructure in the minimum and maximum vulnerable areas shows that these resources are not uniformly distributed throughout the overall vulnerable zone. The methods demonstrated in the Mobile Bay analysis provide an example of how to consider and properly account for vertical uncertainty in elevation-based <span class="hlt">sea-level</span> rise vulnerability assessments, and the advantages of doing so.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.G53A..04H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.G53A..04H"><span>GPS Imaging of Global Vertical Land Motion for <span class="hlt">Sea</span> <span class="hlt">Level</span> Studies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hammond, W. C.; Blewitt, G.; Hamlington, B. D.</p> <p>2015-12-01</p> <p>Coastal vertical land motion contributes to the signal of local relative <span class="hlt">sea</span> <span class="hlt">level</span> change. Moreover, understanding global <span class="hlt">sea</span> <span class="hlt">level</span> change requires understanding local <span class="hlt">sea</span> <span class="hlt">level</span> rise at many locations around Earth. It is therefore essential to understand the regional secular vertical land motion attributable to mantle flow, tectonic deformation, glacial isostatic adjustment, postseismic viscoelastic relaxation, groundwater basin subsidence, elastic rebound from groundwater unloading or other processes that can change the geocentric height of tide gauges anchored to the land. These changes can <span class="hlt">affect</span> inferences of global <span class="hlt">sea</span> <span class="hlt">level</span> rise and should be taken into account for global projections. We present new results of GPS imaging of vertical land motion across most of Earth's continents including its ice-free coastlines around North and South America, Europe, Australia, Japan, parts of Africa and Indonesia. These images are based on data from many independent open access globally distributed continuously recording GPS networks including over 13,500 stations. The data are processed in our system to obtain solutions aligned to the International Terrestrial Reference Frame (ITRF08). To generate images of vertical rate we apply the Median Interannual Difference Adjusted for Skewness (MIDAS) algorithm to the vertical times series to obtain robust non-parametric estimates with realistic uncertainties. We estimate the vertical land motion at the location of 1420 tide gauges locations using Delaunay-based geographic interpolation with an empirically derived distance weighting function and median spatial filtering. The resulting image is insensitive to outliers and steps in the GPS time series, omits short wavelength features attributable to unstable stations or unrepresentative rates, and emphasizes long-wavelength mantle-driven vertical rates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28303196','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28303196"><span>Can community structure track <span class="hlt">sea-level</span> rise? Stress and competitive controls in tidal wetlands.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schile, Lisa M; Callaway, John C; Suding, Katharine N; Kelly, N Maggi</p> <p>2017-02-01</p> <p>Climate change impacts, such as accelerated <span class="hlt">sea-level</span> rise, will <span class="hlt">affect</span> stress gradients, yet impacts on competition/stress tolerance trade-offs and shifts in distributions are unclear. Ecosystems with strong stress gradients, such as estuaries, allow for space-for-time substitutions of stress factors and can give insight into future climate-related shifts in both resource and nonresource stresses. We tested the stress gradient hypothesis and examined the effect of increased inundation stress and biotic interactions on growth and survival of two congeneric wetland sedges, Schoenoplectus acutus and Schoenoplectus americanus. We simulated <span class="hlt">sea-level</span> rise across existing marsh elevations and those not currently found to reflect potential future <span class="hlt">sea-level</span> rise conditions in two tidal wetlands differing in salinity. Plants were grown individually and together at five tidal elevations, the lowest simulating an 80-cm increase in <span class="hlt">sea</span> <span class="hlt">level</span>, and harvested to assess differences in biomass after one growing season. Inundation time, salinity, sulfides, and redox potential were measured concurrently. As predicted, increasing inundation reduced biomass of the species commonly found at higher marsh elevations, with little effect on the species found along channel margins. The presence of neighbors reduced total biomass of both species, particularly at the highest elevation; facilitation did not occur at any elevation. Contrary to predictions, we documented the competitive superiority of the stress tolerator under increased inundation, which was not predicted by the stress gradient hypothesis. Multifactor manipulation experiments addressing plant response to accelerated climate change are integral to creating a more realistic, valuable, and needed assessment of potential ecosystem response. Our results point to the important and unpredicted synergies between physical stressors, which are predicted to increase in intensity with climate change, and competitive forces on biomass as</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003GPC....36....1K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003GPC....36....1K"><span>Climate change scenarios and the effect of <span class="hlt">sea-level</span> rise for Estonia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kont, Are; Jaagus, Jaak; Aunap, Raivo</p> <p>2003-03-01</p> <p>Climate warming due to the enhanced greenhouse effect is expected to have a significant impact on natural environment and human activity in high latitudes. Mostly, it should have a positive effect on human activity. The main threats in Estonia that could be connected with <span class="hlt">sea-level</span> rise are the flooding of coastal areas, erosion of sandy beaches and the destruction of harbour constructions. Possible climate change and its negative impacts in the coastal regions of Estonia are estimated in this paper. Climate change scenarios for Estonia were generated using a Model for the Assessment of Greenhouse-gas Induced Climate Change (MAGICC) and a regional climate change database—SCENanario GENerator (SCENGEN). Three alternative emission scenarios were combined with data from 14 general circulation model experiments. Climate change scenarios for the year 2100 indicate a significant increase in air temperature (by 2.3-4.5 °C) and precipitation (by 5-30%) in Estonia. The highest increase is expected to take place during winter and the lowest increase in summer. Due to a long coastline (3794 km) and extensive low-lying coastal areas, global climate change through <span class="hlt">sea-level</span> rise will strongly <span class="hlt">affect</span> the territory of Estonia. A number of valuable natural ecosystems will be in danger. These include both marine and terrestrial systems containing rare plant communities and suitable breeding places for birds. Most sandy beaches high in recreational value will disappear. However, isostatic land uplift and the location of coastal settlements at a distance from the present coastline reduce the rate of risk. Seven case study areas characterising all the shore types of Estonia have been selected for <span class="hlt">sea-level</span> rise vulnerability and adaptation assessment. Results and estimates of vulnerability to 1.0-m <span class="hlt">sea-level</span> rise by 2100 are presented in this paper. This is the maximum scenario according to which the actually estimated relative <span class="hlt">sea-level</span> rise would vary from 0.9 m (SW Estonia) to 0</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1991JGR....96.6713Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1991JGR....96.6713Q"><span>The history of Post-Miocene <span class="hlt">sea</span> <span class="hlt">level</span> change: Inferences from stratigraphic modeling of Enewetak Atoll</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Quinn, Terrence M.</p> <p>1991-04-01</p> <p>The history of post-Miocene <span class="hlt">sea</span> <span class="hlt">level</span> change has been investigated using a quantitative, one-dimensional stratigraphic forward model. The stratigraphic model produces synthetic stratigraphies, including mineralogy and sediment age versus depth, in response to changes in <span class="hlt">sea</span> <span class="hlt">level</span>, subsidence, sedimentation, and diagenesis. Model outputs, using <span class="hlt">sea</span> <span class="hlt">level</span> curves inferred from passive margin sequence stratigraphy and deep-<span class="hlt">sea</span> foraminiferal oxygen isotope stratigraphy, were compared to the post-Miocene stratigraphy of Enewetak Atoll. Modeling results support high-frequency (104 to 105 years) fluctuations of post-Miocene <span class="hlt">sea</span> <span class="hlt">level</span>. Post-Miocene <span class="hlt">sea</span> <span class="hlt">level</span> elevations significantly greater than modern <span class="hlt">sea</span> <span class="hlt">level</span> elevation are not easily reconciled with the stratigraphy of Enewetak Atoll. Model/data fit is maximized when a rapid subsidence rate for Enewetak Atoll is used. Alternatively, model/data fit may be maximized using a lower subsidence rate for Enewetak and having post-Miocene <span class="hlt">sea</span> <span class="hlt">level</span> elevations significantly lower than modem <span class="hlt">sea</span> <span class="hlt">level</span> elevation. Given the present state of knowledge, much work is still needed to accurately decipher the record of post-Miocene <span class="hlt">sea</span> <span class="hlt">level</span> change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010JGRC..11512016G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010JGRC..11512016G"><span>Steric and mass-induced <span class="hlt">sea</span> <span class="hlt">level</span> variations in the Mediterranean <span class="hlt">Sea</span> revisited</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>GarcíA-GarcíA, D.; Chao, B. F.; Boy, J.-P.</p> <p>2010-12-01</p> <p>The total <span class="hlt">sea</span> <span class="hlt">level</span> variation (SLV) is the combination of steric and mass-induced SLV, whose exact shares are key to understanding the oceanic response to climate system changes. Total SLV can be observed by radar altimetry satellites such as TOPEX/POSEIDON and Jason 1/2. The steric SLV can be computed through temperature and salinity profiles from in situ measurements or from ocean general circulation models (OGCM), which can assimilate the said observations. The mass-induced SLV can be estimated from its time-variable gravity (TVG) signals. We revisit this problem in the Mediterranean <span class="hlt">Sea</span> estimating the observed, steric, and mass-induced SLV, for the latter we analyze the latest TVG data set from the GRACE (Gravity Recovery and Climate Experiment) satellite mission launched in 2002, which is 3.5 times longer than in previous studies, with the application of a two-stage anisotropic filter to reduce the noise in high-degree and -order spherical harmonic coefficients. We confirm that the intra-annual total SLV are only produced by water mass changes, a fact explained in the literature as a result of the wind field around the Gibraltar Strait. The steric SLV estimated from the residual of "altimetry minus GRACE" agrees in phase with that estimated from OGCMs and in situ measurements, although showing a higher amplitude. The net water fluxes through both the straits of Gibraltar and Sicily have also been estimated accordingly.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11.8231G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11.8231G"><span>Steric and Mass-Induced <span class="hlt">Sea</span> <span class="hlt">Level</span> Variations in the Mediterranean <span class="hlt">Sea</span>, Revisited</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Garcia-Garcia, D.; Chao, B. F.; Boy, J.-P.</p> <p>2009-04-01</p> <p>Observed by radar altimetry satellites such as TOPEX/Poseidon (T/P) and Jason-1/2, the total <span class="hlt">Sea</span> <span class="hlt">Level</span> Variations (SLV) are produced by a combination of the steric and mass-induced components. The steric SLV can be computed from in situ measurements of temperature and salinity profiles, or from Ocean General Circulation Models (OGCM) that can assimilate those measurements. Mass-induced SLV can be estimated, since 2002, from Time-Variable Gravity (TVG) measurements by the GRACE satellite mission. This methodology has been successfully applied in estimation of the global ocean mass-induced SLV. However, some difficulties arise when studying semi-enclosed basins due to land aliasing of the GRACE TVG signal. The problem is specially complicated in the Mediterranean <span class="hlt">Sea</span> as reported in previous studies. We revisit this problem analyzing release 4 of the GRACE data set, which represents a time series 3 times longer than in previous studies, by means of new and more efficient filters to reduce the noise in the high degree and order spherical harmonics coefficients. The seasonal and non-seasonal signals are analyzed. From the comparison of GRACE with altimetry data a general underestimation of the steric term is observed in the OGCMs used.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMNH11D..07B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMNH11D..07B"><span>Adaptation to <span class="hlt">Sea</span> <span class="hlt">Level</span> Rise in Coastal Units of the National Park Service (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beavers, R. L.</p> <p>2010-12-01</p> <p>83 National Park Service (NPS) units contain nearly 12,000 miles of coastal, estuarine and Great Lakes shoreline and their associated resources. Iconic natural features exist along active shorelines in NPS units, including, e.g., Cape Cod, Padre Island, Hawaii Volcanoes, and the Everglades. Iconic cultural resources managed by NPS include the Cape Hatteras Lighthouse, Fort Sumter, the Golden Gate, and heiaus and fish traps along the coast of Hawaii. Impacts anticipated from <span class="hlt">sea</span> <span class="hlt">level</span> rise include inundation and flooding of beaches and low lying marshes, shoreline erosion of coastal areas, and saltwater intrusion into the water table. These impacts and other coastal hazards will threaten park beaches, marshes, and other resources and values; alter the viability of coastal roads; and require the NPS to re-evaluate the financial, safety, and environmental implications of maintaining current projects and implementing future projects in ocean and coastal parks in the context of <span class="hlt">sea</span> <span class="hlt">level</span> rise. Coastal erosion will increase as <span class="hlt">sea</span> <span class="hlt">levels</span> rise. Barrier islands along the coast of Louisiana and North Carolina may have already passed the threshold for maintaining island integrity in any scenario of <span class="hlt">sea</span> <span class="hlt">level</span> rise (U.S. Climate Change Science Program Synthesis and Assessment Program Report 4.1). Consequently, <span class="hlt">sea</span> <span class="hlt">level</span> rise is expected to hasten the disappearance of historic coastal villages, coastal wetlands, forests, and beaches, and threaten coastal roads, homes, and businesses. While <span class="hlt">sea</span> <span class="hlt">level</span> is rising in most coastal parks, some parks are experiencing lower water <span class="hlt">levels</span> due to isostatic rebound and lower lake <span class="hlt">levels</span>. NPS funded a Coastal Vulnerability Project to evaluate the physical and geologic factors <span class="hlt">affecting</span> 25 coastal parks. The USGS Open File Reports for each park are available at http://woodshole.er.usgs.gov/project-pages/. These reports were designed to inform park planning efforts. NPS conducted a Storm Vulnerability Project to provide ocean and coastal</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMEP13A0832P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMEP13A0832P"><span>On the significance of incorporating shoreline changes for evaluating coastal hydrodynamics under <span class="hlt">sea</span> <span class="hlt">level</span> rise scenarios</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Passeri, D.; Hagen, S. C.; Medeiros, S. C.</p> <p>2013-12-01</p> <p><span class="hlt">Sea</span> <span class="hlt">level</span> rise (SLR) threatens coastal environments with loss of land, inundation of coastal wetlands, and increased flooding during extreme storm events. Research has shown that SLR is a major factor in the long-term, gradual retreat of shorelines (Fitzgerald et al., 2008). Along sandy shorelines, retreat has a more dynamic effect than just inundation due to rising water <span class="hlt">levels</span>, including the physical process of erosion in which sand is removed from the shoreface and deposited offshore. This has the potential to <span class="hlt">affect</span> ecological habitats as well as coastal communities. Although SLR induces seaward retreat of shorelines, many shorelines especially within the vicinity of inlets may experience accretion due to sediment trapping or beach replenishment (Aubrey and Giese, 1993, Browder and R.G., 1999). This study examines the influence of including projected shoreline changes under future <span class="hlt">sea</span> states into hydrodynamic modeling within the Northern Gulf of Mexico (NGOM). The NGOM coastline is an economically and ecologically significant area, comprised of various bays, barrier islands and mainland beaches. Projected shorelines and nearshore morphology for the year 2050 are derived from the Coastal Vulnerability Index (CVI) shoreline change rates (Thieler and Hammer-Klose, 1999) and used in conjunction with the 'Bruun Rule effect'(Bruun, 1962). A large scale hydrodynamic model forced by astronomic tides and hurricane winds and pressures is used to simulate present conditions, a high projection of the 2050 <span class="hlt">sea</span> state (18 in of SLR in accordance with Parris et al. (2012)) and the 2050 high <span class="hlt">sea</span> state with 2050 shorelines to test the sensitivity of the system to the projected shoreline changes. Results show that shoreline changes coupled with <span class="hlt">sea</span> <span class="hlt">level</span> rise increases tidal inundation along shorelines, amplifies overtopping of barrier islands during storm surge events, and heightens inland storm surge inundation. It is critical to include estimates of shoreline and barrier</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18..649S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18..649S"><span>Late Glacial to Holocene evolution and <span class="hlt">sea-level</span> history of Gulf of Gemlik, <span class="hlt">Sea</span> of Marmara, Turkey</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sabuncu, Asen; Kadir Eriş, K.; Kaslilar, Ayse; Namık Çaǧatay, M.; Gasperini, Luca; Filikçi, Betül</p> <p>2016-04-01</p> <p>The Gulf of Gemlik is an E-W elongated trans-tensional basin with a maximum depth of 113 m, located on the middle strand of the North Anatolian Fault (NAF) in the south eastern part of the <span class="hlt">Sea</span> of Marmara (SoM). While during the Holocene the <span class="hlt">sea</span> <span class="hlt">level</span> in the Gulf of Gemlik changed in tandem with the water <span class="hlt">level</span> changes in the SoM, it may have been different in the late glacial when the <span class="hlt">Sea</span> of Marmara was lacustrine. Beside the tectonic activity related to the NAFZ, eustatic <span class="hlt">sea</span> <span class="hlt">level</span> changes would have controlled the basin evolution and consequent sedimentary history during the different paleocanographic phases of the SoM. Considering the limited studies on the late glacial-Holocene stratigraph of the Gulf of Gemlik, this study aims to investigate the depositional units and their environments with respect to different allogenic and autogenic controls. For these purposes, we analyzed over 300 2 - 7 kHz bandwidth high-resolution gridded seismic sub-bottom CHIRP profiles together with 70 kHz high resolution multibeam bathymetry with backscatter data. Four seismic stratigraphic units were defined and correlated with chronstratigraphic units in five piston cores covering the last 15.8 ka BP according to radiocarbon ages (14C). The depth-scale accuracy of chronostratigraphic units in cores is of key importance for the precise calculation of sedimentation rates. Correlation between the seismic profiles and cores were made by matching Multi-Sensor Core-Logger (MSCL) data and seismic reflection coefficients and amplitudes for different stratigraphic units. The impedance data derived from the logger were used to generate a synthetic seismogram. We used an approach to display, estimate, and correct the depth-scale discrepancies due to oversampling <span class="hlt">affecting</span> the upper part of sedimentary series during piston coring. The method is based on the resynchronization of synthetic seismograms computed from high-quality physical property logs to the corresponding CHIRP profiles. Each</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..1413197M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..1413197M"><span>Effects of large <span class="hlt">sea-level</span> variations in connected basins: the Dacian - Black <span class="hlt">Sea</span> system of the Eastern Paratethys</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Munteanu, I.; Matenco, L.; Dinu, C.; Cloetingh, S.</p> <p>2012-04-01</p> <p><span class="hlt">Sea-level</span> changes provide an important control on the interplay between accommodation space and sediment supply, in particular for shallow-water basins where the available space is limited. Sediment exchange between connected basins separated by a subaqueous sill (bathymetric threshold) is still not well understood. When <span class="hlt">sea-level</span> falls below the bathymetric <span class="hlt">level</span> of this separating sill, the shallow-water basin evolution is controlled by its erosion and rapid fill. Once this marginal basin is filled, the sedimentary depocenter shifts to the open marine basin (outward shift). With new accommodation space created during the subsequent <span class="hlt">sea-level</span> rise, sediment depocenter shifts backwards to the marginal basin (inward shift). This new conceptual model is tested here in the context of Late Miocene to Quaternary evolution of the open connection between Dacian and Black <span class="hlt">Sea</span> basins. By the means of seismic sequence stratigraphic analysis of the Miocene-Pliocene evolution of this Eastern Paratethys domain, this case study demonstrates these shifts in sedimentary depocenter between basins. An outward shift occurs with a delay that corresponds to the time required to fill the remaining accommodation space in the Dacian Basin below the sill that separates it from the Black <span class="hlt">Sea</span>. This study provides novel insight on the amplitude and sedimentary geometry of the Messinian Salinity Crisis (MSC) event in the Black <span class="hlt">Sea</span>. A large (1.3 - 1.7km) <span class="hlt">sea-level</span> drop is demonstrated by quantifying coeval sedimentation patterns that change to mass-flows and turbiditic deposits in the deep-<span class="hlt">sea</span> part of this main sink. The post-MSC sediment routing continued into the present-day pattern of Black <span class="hlt">Sea</span> rivers discharge.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010GeoRL..3723702B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010GeoRL..3723702B"><span>Imprint of the El Niño Modoki on decadal <span class="hlt">sea</span> <span class="hlt">level</span> changes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Behera, Swadhin; Yamagata, Toshio</p> <p>2010-12-01</p> <p>Decadal variation in <span class="hlt">sea</span> <span class="hlt">level</span> is shown to manifest as higher than normal <span class="hlt">sea</span> <span class="hlt">level</span> in the central Pacific flanked by lower than normal <span class="hlt">sea</span> <span class="hlt">level</span> on either side of the basin during the early 21st century. This abnormal condition is evidently aided by frequent occurrences of El Niño Modoki events and associated wind convergence to the dateline during 2000-2004. The <span class="hlt">sea</span> <span class="hlt">level</span> rise in central Pacific succeeded a phase of lower than normal <span class="hlt">sea</span> <span class="hlt">level</span> associated with La Niña Modoki events toward the end of 20th century. A correlation analysis confirms the dominant influence of El Niño/La Niña Modoki on the <span class="hlt">sea</span> <span class="hlt">level</span> rise in the central Pacific as compared to that of the El Niño/La Niña. This influence can even be seen in remote regions such as the coasts of California and Mauritius through atmospheric teleconnections.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoRL..43.3351V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoRL..43.3351V"><span>The impact of groundwater depletion on spatial variations in <span class="hlt">sea</span> <span class="hlt">level</span> change during the past century</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Veit, Emeline; Conrad, Clinton P.</p> <p>2016-04-01</p> <p>Continental groundwater loss during the past century has elevated <span class="hlt">sea</span> <span class="hlt">level</span> by up to ~25 mm. The mass unloading associated with this depletion locally uplifts Earth's solid surface and depresses the geoid, leading to slower relative <span class="hlt">sea</span> <span class="hlt">level</span> rise near areas of significant groundwater loss. We computed spatial variations in <span class="hlt">sea</span> <span class="hlt">level</span> using a model of the solid Earth's response to estimates of groundwater depletion during the past century and find large negative deviations of ~0.4 mm/yr along the coastlines of western North America and southern Asia. This approximately corresponds to the difference between rates of <span class="hlt">sea</span> <span class="hlt">level</span> rise measured by tide gauges in these regions since 1930 and average rates inferred from global reconstructions. Groundwater-induced regional variations in <span class="hlt">sea</span> <span class="hlt">level</span> can be larger than those due to postglacial rebound and interseismic deformation and should become increasingly important in the future as both groundwater depletion and <span class="hlt">sea</span> <span class="hlt">level</span> rise accelerate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016E%26PSL.451...10S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016E%26PSL.451...10S"><span>Sedimentary architecture of the Bohai <span class="hlt">Sea</span> China over the last 1 Ma and implications for <span class="hlt">sea-level</span> changes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shi, Xuefa; Yao, Zhengquan; Liu, Qingsong; Larrasoaña, Juan Cruz; Bai, Yazhi; Liu, Yanguang; Liu, Jihua; Cao, Peng; Li, Xiaoyan; Qiao, Shuqing; Wang, Kunshan; Fang, Xisheng; Xu, Taoyu</p> <p>2016-10-01</p> <p>Sedimentary architecture dominated by transgression-regression cycles in the shallow Bohai shelf region contains information about global <span class="hlt">sea-level</span>, climate and local tectonics. However, previous studies of transgression-regression cycles in this region at orbital timescales that extend back to the early Pleistocene are sparse, mainly because of the shortage of well-dated long cores. Although transgression-regression sedimentary cycles in the region have been interpreted in terms of local tectonics, <span class="hlt">sea-level</span>, and climate change, the detailed structure of marine transgressions and their significance for Quaternary global <span class="hlt">sea-level</span> variations remains to be examined. In this study, we present an integrated sedimentological, geochemical and paleontological study of a 212.4 m (∼1 Ma) core (BH08) recovered from the Bohai <span class="hlt">Sea</span>, China, for which an astronomically-based age model is available. Correspondence between marine-terrestrial sedimentary cycles and global <span class="hlt">sea-level</span> fluctuations suggests that stacking of marine and terrestrial sediments was driven mainly by glacio-eustatic <span class="hlt">sea-level</span> fluctuations in a context in which tectonic subsidence was largely balanced by sediment supply over the last ∼1 Ma. We report a dominant 100-kyr cycle beginning at ∼650 ka, which reflects the worldwide influence of the mid-Pleistocene transition (MPT) in <span class="hlt">sea-level</span> records. We find that neritic deposits after the MPT were relatively thicker than before the MPT, which indicates an important control of the MPT on sedimentary architecture through lengthening of the duration of <span class="hlt">sea-level</span> highstands.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3704648','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3704648"><span>Non-Linear Interactions Determine the Impact of <span class="hlt">Sea-Level</span> Rise on Estuarine Benthic Biodiversity and Ecosystem Processes</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Yamanaka, Tsuyuko; Raffaelli, David; White, Piran C. L.</p> <p>2013-01-01</p> <p><span class="hlt">Sea-level</span> rise induced by climate change may have significant impacts on the ecosystem functions and ecosystem services provided by intertidal sediment ecosystems. Accelerated <span class="hlt">sea-level</span> rise is expected to lead to steeper beach slopes, coarser particle sizes and increased wave exposure, with consequent impacts on intertidal ecosystems. We examined the relationships between abundance, biomass, and community metabolism of benthic fauna with beach slope, particle size and exposure, using samples across a range of conditions from three different locations in the UK, to determine the significance of sediment particle size beach slope and wave exposure in <span class="hlt">affecting</span> benthic fauna and ecosystem function in different ecological contexts. Our results show that abundance, biomass and oxygen consumption of intertidal macrofauna and meiofauna are <span class="hlt">affected</span> significantly by interactions among sediment particle size, beach slope and wave exposure. For macrofauna on less sloping beaches, the effect of these physical constraints is mediated by the local context, although for meiofauna and for macrofauna on intermediate and steeper beaches, the effects of physical constraints dominate. Steeper beach slopes, coarser particle sizes and increased wave exposure generally result in decreases in abundance, biomass and oxygen consumption, but these relationships are complex and non-linear. <span class="hlt">Sea-level</span> rise is likely to lead to changes in ecosystem structure with generally negative impacts on ecosystem functions and ecosystem services. However, the impacts of <span class="hlt">sea-level</span> rise will also be <span class="hlt">affected</span> by local ecological context, especially for less sloping beaches. PMID:23861863</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23861863','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23861863"><span>Non-linear interactions determine the impact of <span class="hlt">sea-level</span> rise on estuarine benthic biodiversity and ecosystem processes.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yamanaka, Tsuyuko; Raffaelli, David; White, Piran C L</p> <p>2013-01-01</p> <p><span class="hlt">Sea-level</span> rise induced by climate change may have significant impacts on the ecosystem functions and ecosystem services provided by intertidal sediment ecosystems. Accelerated <span class="hlt">sea-level</span> rise is expected to lead to steeper beach slopes, coarser particle sizes and increased wave exposure, with consequent impacts on intertidal ecosystems. We examined the relationships between abundance, biomass, and community metabolism of benthic fauna with beach slope, particle size and exposure, using samples across a range of conditions from three different locations in the UK, to determine the significance of sediment particle size beach slope and wave exposure in <span class="hlt">affecting</span> benthic fauna and ecosystem function in different ecological contexts. Our results show that abundance, biomass and oxygen consumption of intertidal macrofauna and meiofauna are <span class="hlt">affected</span> significantly by interactions among sediment particle size, beach slope and wave exposure. For macrofauna on less sloping beaches, the effect of these physical constraints is mediated by the local context, although for meiofauna and for macrofauna on intermediate and steeper beaches, the effects of physical constraints dominate. Steeper beach slopes, coarser particle sizes and increased wave exposure generally result in decreases in abundance, biomass and oxygen consumption, but these relationships are complex and non-linear. <span class="hlt">Sea-level</span> rise is likely to lead to changes in ecosystem structure with generally negative impacts on ecosystem functions and ecosystem services. However, the impacts of <span class="hlt">sea-level</span> rise will also be <span class="hlt">affected</span> by local ecological context, especially for less sloping beaches.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003JGRC..108.3335P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003JGRC..108.3335P"><span>Influence of interannual rainfall anomalies on <span class="hlt">sea</span> <span class="hlt">level</span> variations in the tropical Indian Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Perigaud, Claire; McCreary, Julian P.</p> <p>2003-10-01</p> <p>A halo-thermal, reduced-gravity model with four active layers is used to investigate how interannual rainfall anomalies <span class="hlt">affect</span> <span class="hlt">sea</span> surface height (SSH) variability in the Indian Ocean. The model is forced by monthly varying winds observed over the period 1980-2000 in two experiments that differ by their rainfall forcing, Run FSU and Run Arkin, forced by climatological and interannually varying rainfall, respectively. Compared to the large impact of wind on SSH (about 30 cm), the impact of rain is much smaller. Its maximum (found in the southeastern Indian Ocean during the rainfall deficits of 1994 and 1997) is only 2 cm. Because rainfall significantly <span class="hlt">affects</span> model salinity and temperature, the deficits make the layers of Run Arkin colder and saltier than in Run FSU, causing a -5 cm change in <span class="hlt">sea</span> <span class="hlt">level</span>. Baroclinic adjustments also occur such that the top (bottom) two layers are thicker (thinner), increasing <span class="hlt">sea</span> <span class="hlt">level</span> by 3 cm and hence significantly reducing the SSH change due to steric effects alone. SSH variability in either Run Arkin or Run FSU compares very well with TOPEX data. Although the impact of rainfall on SSH is negligible, salinity variations significantly <span class="hlt">affect</span> dynamic-height calculations of SSH. In the model, the neglect of salinity variations leads to an error of 5 to 10 cm along the eastern boundary, in the Bay of Bengal, and in the interior ocean south of 8°S. This error is validated by the difference between TOPEX data and SSH derived from observed temperature profiles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5928115','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5928115"><span>(Reduce uncertainty in projection of future <span class="hlt">sea-level</span> change due to ice wastage)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Meier, M.F.</p> <p>1991-01-01</p> <p>Three basic goals were stated in the original proposal. These were: (1) develop an understanding of the heat and mass flow into subfreezing snow and firn, in order to model the evolution of the temperature distribution and the infiltration rates through the firn; (2) relate changes in climate, as given by general circulation model predictions, to changes in the surface mass and energy balances of glaciers; and (3) use the above results to analyze the effects of changed surface mass and energy balances on the flow of meltwater through snow and firn, and on the runoff from these glaciers, in a CO{sub 2}-<span class="hlt">affected</span> climate. This final report summarizes our progress toward these goals. The primary product of this research program has been the communication of this progress in the form of publications in the scientific literature and presentations at scientific meetings. Our research activities in the past three years have provided a new basis for modeling of multiphase flow in subfreezing snow, new field data on the structural properties of arctic firn pertinent to hydrological modeling, and estimates of <span class="hlt">sea</span> <span class="hlt">level</span> change in response to changing patterns of runoff from the Greenland Ice Sheet. We conclude that forecasts of future <span class="hlt">sea</span> <span class="hlt">level</span> changes from all glacier runoff sources may be in error by amounts on the order of +8 cm over the next 150 years, due to the lag in generating runoff to the <span class="hlt">sea</span>. Our specific research products include two distributed-parameter models of water flow through snow with melting and freezing, a theoretical model of wetting-front advance into subfreezing snow for inclusion in a future model, and a simple large-scale model of the response of Greenland runoff in a changing climate which provides estimates of the effect of melt water refreezing phenomena on <span class="hlt">sea</span> <span class="hlt">level</span> changes in response to a range of possible future climates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.G41A0876F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.G41A0876F"><span>Effects of sediment transport and deposition on crustal loading, Earth's gravitational field, and <span class="hlt">sea</span> <span class="hlt">level</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ferrier, K.; Mitrovica, J. X.; Perron, T.; Milne, G. A.; Wickert, A. D.</p> <p>2012-12-01</p> <p>Spatial patterns in static <span class="hlt">sea</span> <span class="hlt">level</span> are controlled by the interplay between the history of ice mass variations and the associated deformational, gravitational and rotational perturbations in the Earth's state. Over the last decade, there has been a renewed effort to extend classic treatments of ice-age <span class="hlt">sea-level</span> change (Farrell and Clark, 1976) to incorporate effects such as shoreline migration due to the local onlap or offlap of seawater and changes in the extent of grounded, marine-based ice, as well as feedbacks between <span class="hlt">sea</span> <span class="hlt">level</span> and the orientation of Earth's rotation axis. To date, the impact of sediment transport - whether in the context of glacial processes, or other processes such as fluvial deposition - has not been incorporated into a gravitationally self-consistent <span class="hlt">sea-level</span> theory. Here we briefly summarize the main elements of a new <span class="hlt">sea-level</span> theory that includes sediment transport, and we apply this new theory to investigate crustal deformation and <span class="hlt">sea-level</span> changes driven by sediment deposition on the Mississippi fan in the Gulf of Mexico. The calculations incorporate sediment transport from the start of the last glacial cycle through to the present and are constrained to conserve sediment and ocean mass. We compare relative <span class="hlt">sea</span> <span class="h