Spatial variations in atmospheric CO2 concentrations during the ARCTAS-CARB 2008 Summer Campaign

NASA Astrophysics Data System (ADS)

Vadrevu, K. P.; Choi, Y.; Vay, S. A.

2009-12-01

The Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) was a major NASA field campaign designed to understand the transport and transformation of trace gases and aerosols on transcontinental and intercontinental scales and their impact on the composition of the arctic atmosphere and climate. Preceding the summer ARCTAS deployment, measurements were conducted over the state of California in collaboration with the California Air Resources Board (CARB) utilizing the airborne chemistry payload already integrated on the NASA DC-8. In situ CO2 measurements were made using a modified infrared CO2 gas analyzer having a precision of 0.1 ppmv and accuracy of ±0.25 ppmv traceable to the WMO scale. This analysis focuses on the atmospheric CO2 variability and biospheric/atmospheric exchange over California. We used multi-satellite remote sensing datasets to relate airborne observations of CO2 to infer sources and sinks. Georeferencing the airborne CO2 transect data with the LANDSAT derived land cover datasets over California suggested significant spatial variations. The airborne CO2 concentrations were found to be 375-380ppm over the Pacific ocean, 385-391ppm in the highly vegetated agricultural areas, 400-420 in the near coastal areas and greater than 425ppmv in the urban areas. Analysis from MODIS fire products suggested significant fires in northern California. CO2 emissions exceeded 425ppmv in the fire affected regions, where mostly Douglas and White Fir conifers and mixed Chaparral vegetation was burnt. Analysis from GOES-East and GOES-West visible satellite imagery suggested significant smoke plumes moving from northern California towards Nevada and Idaho. To infer the biospheric uptake of CO2, we tested the potential correlations between airborne CO2 data and MODIS normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI). Results suggested significant anti-correlations between the airborne CO2 data and

Chris Cantrell and Becky Anderson of the National Center for Atmospheric Research assess the CIMS instrument's operation during ARCTAS mission preparations

NASA Image and Video Library

2008-03-07

Climate researchers from the National Center for Atmospheric Research (NCAR) and several universities install and perform functional checkouts of a variety of sensitive atmospheric instruments on NASA's DC-8 airborne laboratory prior to beginning the ARCTAS mission.

Jingqiu Moa and Xinrong Ren check out Pennsylvania State University's Airborne Tropospheric Hydrogen Oxides Sensor instrument during the ARCTAS mission upload

NASA Image and Video Library

2008-03-07

Climate researchers from the National Center for Atmospheric Research (NCAR) and several universities install and perform functional checkouts of a variety of sensitive atmospheric instruments on NASA's DC-8 airborne laboratory prior to beginning the ARCTAS mission.

Assessment of Anthropogenic and Biomass Burning Impact on Aerosol Properties over California as Observed During ARCTAS-CA

NASA Astrophysics Data System (ADS)

Thornhill, K. L.; Anderson, B.; Chen, G.; Beyersdorf, A. J.; Winstead, E. L.; Dibb, J. E.; Scheuer, E. M.; Weber, R.; Lathem, T. L.; Jimenez, J. L.; Cubison, M.; Kondo, Y.; Wennberg, P. O.; Weinheimer, A. J.; Wisthaler, A.

2009-12-01

In the summer of 2008, measurements of aerosols were made on-board the NASA DC-8 over the state of California, as part of the second phase of the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) on behalf of the California Air resources Board (CARB). The DC-8 made four flights, between 18 June and 26 June, totaling 33 hours, to examine California’s atmosphere to better understand the chemical dynamics of smog and greenhouse gases over the state. Serendipitously, from a science perspective, this time period was marked by numerous wildfires spread throughout the state. The NASA DC-8 had a suite of aerosol instruments, capable of measuring the number concentrations, optical properties, and size distributions of aerosols between 0.003 and 1500 um. In this presentation, we will characterize aerosols sampled over the Los Angeles basin, which included several missed approaches at Los Angeles International Airport (LAX), traverses through the Long Beach and Santa Barbara ship channels, sampling in and out of the marine boundary layer, and encounters with outflow of forest fires mixed with urban smog. The evolution of the aerosols during the day will be examined, as the smog builds up within the basin and the plume travels out of the basin into the surrounding atmosphere.

An investigation of methods for injecting emissions from boreal wildfires using WRF-Chem during ARCTAS

NASA Astrophysics Data System (ADS)

Sessions, W. R.; Fuelberg, H. E.; Kahn, R. A.; Winker, D. M.

2010-11-01

The Weather Research and Forecasting Model (WRF) is considered a "next generation" mesoscale meteorology model. The inclusion of a chemistry module (WRF-Chem) allows transport simulations of chemical and aerosol species such as those observed during NASA's Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) in 2008. The ARCTAS summer deployment phase during June and July coincided with large boreal wildfires in Saskatchewan and Eastern Russia. One of the most important aspects of simulating wildfire plume transport is the height at which emissions are injected. WRF-Chem contains an integrated one-dimensional plume rise model to determine the appropriate injection layer. The plume rise model accounts for thermal buoyancy associated with fires and the local atmospheric stability. This study compares results from the plume model against those of two more traditional injection methods: Injecting within the planetary boundary layer, and in a layer 3-5 km above ground level. Fire locations are satellite derived from the GOES Wildfire Automated Biomass Burning Algorithm (WF_ABBA) and the MODIS thermal hotspot detection. Two methods for preprocessing these fire data are compared: The prep_chem_sources method included with WRF-Chem, and the Naval Research Laboratory's Fire Locating and Monitoring of Burning Emissions (FLAMBE). Results from the simulations are compared with satellite-derived products from the AIRS, MISR and CALIOP sensors. Results show that the FLAMBE pre-processor produces more realistic injection heights than does prep_chem_sources. The plume rise model using FLAMBE provides the best agreement with satellite-observed injection heights. Conversely, when the planetary boundary layer or the 3-5 km AGL layer were filled with emissions, the resulting injection heights exhibit less agreement with observed plume heights. Results indicate that differences in injection heights produce different transport pathways. These

Distribution of Aerosols in the Arctic as Observed by CALIOP

NASA Astrophysics Data System (ADS)

Winker, D.; Kittaka, C.

2007-12-01

The Arctic climate is now recognized to be uniquely sensitive to atmospheric perturbations. Pollution aerosols and smoke from boreal fires have potentially important impacts on Arctic climate but there are many uncertainties. Aerosol in the Arctic, generally referred to as "Arctic haze", has been studied with great interest for over thirty years. Much has been learned about the composition and sources of the haze yet our knowledge is largely based on long term measurements at a very few widely dispersed sites, augmented by modeling activities and occasional field campaigns. Transport pathways from source regions into the Arctic are not well understood. Emission patterns have changed over the last several decades, but the impact of this on concentrations and distribution of Arctic haze are understood only in the crudest sense. Due to poor lighting conditions, extended periods of darkness, and surfaces covered by snow and ice, satellite sensors have been unable to provide much information on Arctic haze to date. The CALIPSO satellite carries CALIOP, a two-wavelength polarization lidar, optimized for profiling clouds and aerosols. CALIOP has been acquiring global observations since June 2006 and provides our first opportunity to observe the distribution and seasonal variation of aerosol in the Arctic. The Arctic is characterized by the prevalence of optically thin ice clouds and clouds composed of supercooled water, often occurring in the same atmospheric column along with aerosol. CALIOP depolarization signals are used to discriminate Arctic haze from optically thin cirrus and diamond dust. Two-wavelength returns aid in the discrimination of aerosol and optically thin water cloud. Results of initial analyses of CALIOP aerosol observations in the Arctic will be presented. This work is a preliminary analysis in support of the NASA Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) field campaign planned for April 2008.

Reactive nitrogen, ozone and ozone production in the Arctic troposphere and the impact of stratosphere-troposphere exchange

NASA Astrophysics Data System (ADS)

Liang, Q.; Rodriguez, J. M.; Douglass, A. R.; Crawford, J. H.; Olson, J. R.; Apel, E.; Bian, H.; Blake, D. R.; Brune, W.; Chin, M.; Colarco, P. R.; da Silva, A.; Diskin, G. S.; Duncan, B. N.; Huey, L. G.; Knapp, D. J.; Montzka, D. D.; Nielsen, J. E.; Pawson, S.; Riemer, D. D.; Weinheimer, A. J.; Wisthaler, A.

2011-12-01

We use aircraft observations obtained during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) mission to examine the distributions and source attributions of O3 and NOy in the Arctic and sub-Arctic region. Using a number of marker tracers, we distinguish various air masses from the background troposphere and examine their contributions to NOx, O3, and O3 production in the Arctic troposphere. The background Arctic troposphere has a mean O3 of ~60 ppbv and NOx of ~25 pptv throughout spring and summer with CO decreasing from ~145 ppbv in spring to ~100 ppbv in summer. These observed mixing ratios are not notably different from the values measured during the 1988 ABLE-3A and the 2002 TOPSE field campaigns despite the significant changes in emissions and stratospheric ozone layer in the past two decades that influence Arctic tropospheric composition. Air masses associated with stratosphere-troposphere exchange are present throughout the mid and upper troposphere during spring and summer. These air masses, with mean O3 concentrations of 140-160 ppbv, are significant direct sources of O3 in the Arctic troposphere. In addition, air of stratospheric origin displays net O3 formation in the Arctic due to its sustainable, high NOx (75 pptv in spring and 110 pptv in summer) and NOy (~800 pptv in spring and ~1100 pptv in summer). The air masses influenced by the stratosphere sampled during ARCTAS-B also show conversion of HNO3 to PAN. This active production of PAN is the result of increased degradation of ethane in the stratosphere-troposphere mixed air mass to form CH3CHO, followed by subsequent formation of PAN under high NOx conditions. These findings imply that an adequate representation of stratospheric NOy input, in addition to stratospheric O3 influx, is essential to accurately simulate tropospheric Arctic O3, NOx and PAN in chemistry transport models. Plumes influenced by recent anthropogenic and biomass burning emissions

Climbing the Slope of Enlightenment during NASA's Arctic Boreal Vulnerability Experiment

NASA Astrophysics Data System (ADS)

Griffith, P. C.; Hoy, E.; Duffy, D.; McInerney, M.

2015-12-01

The Arctic Boreal Vulnerability Experiment (ABoVE) is a new field campaign sponsored by NASA's Terrestrial Ecology Program and designed to improve understanding of the vulnerability and resilience of Arctic and boreal social-ecological systems to environmental change (http://above.nasa.gov). ABoVE is integrating field-based studies, modeling, and data from airborne and satellite remote sensing. The NASA Center for Climate Simulation (NCCS) has partnered with the NASA Carbon Cycle and Ecosystems Office (CCEO) to create a high performance science cloud for this field campaign. The ABoVE Science Cloud combines high performance computing with emerging technologies and data management with tools for analyzing and processing geographic information to create an environment specifically designed for large-scale modeling, analysis of remote sensing data, copious disk storage for "big data" with integrated data management, and integration of core variables from in-situ networks. The ABoVE Science Cloud is a collaboration that is accelerating the pace of new Arctic science for researchers participating in the field campaign. Specific examples of the utilization of the ABoVE Science Cloud by several funded projects will be presented.

Reactive Nitrogen, Ozone and Ozone Production in the Arctic Troposphere and the Impact of Stratosphere-Troposphere Exchange

NASA Technical Reports Server (NTRS)

Liang, Q.; Rodriquez, J. M.; Douglass, A. R.; Crawford, J. H.; Apel, E.; Bian, H.; Blake, D. R.; Brune, W.; Chin, M.; Colarco, P. R.;

Analysis of Snow Bidirectional Reflectance from ARCTAS Spring-2008 Campaign

NASA Technical Reports Server (NTRS)

Lyapustin, A.; Gatebe, C. K.; Redemann, J.; Kahn, R.; Brandt, R.; Russell, P.; King, M. D.; Pedersen, C. A.; Gerland, S.; Poudyal, R.;

Arctic-COLORS (Coastal Land Ocean Interactions in the Arctic) - a NASA field campaign scoping study to examine land-ocean interactions in the Arctic

NASA Astrophysics Data System (ADS)

Hernes, P.; Tzortziou, M.; Salisbury, J.; Mannino, A.; Matrai, P.; Friedrichs, M. A.; Del Castillo, C. E.

2014-12-01

The Arctic region is warming faster than anywhere else on the planet, triggering rapid social and economic changes and impacting both terrestrial and marine ecosystems. Yet our understanding of critical processes and interactions along the Arctic land-ocean interface is limited. Arctic-COLORS is a Field Campaign Scoping Study funded by NASA's Ocean Biology and Biogeochemistry Program that aims to improve understanding and prediction of land-ocean interactions in a rapidly changing Arctic coastal zone, and assess vulnerability, response, feedbacks and resilience of coastal ecosystems, communities and natural resources to current and future pressures. Specific science objectives include: - Quantify lateral fluxes to the arctic inner shelf from (i) rivers and (ii) the outer shelf/basin that affect biology, biodiversity, biogeochemistry (i.e. organic matter, nutrients, suspended sediment), and the processing rates of these constituents in coastal waters. - Evaluate the impact of the thawing of Arctic permafrost within the river basins on coastal biology, biodiversity and biogeochemistry, including various rates of community production and the role these may play in the health of regional economies. - Assess the impact of changing Arctic landfast ice and coastal sea ice dynamics. - Establish a baseline for comparison to future change, and use state-of-the-art models to assess impacts of environmental change on coastal biology, biodiversity and biogeochemistry. A key component of Arctic-COLORS will be the integration of satellite and field observations with coupled physical-biogeochemical models for predicting impacts of future pressures on Arctic, coastal ocean, biological processes and biogeochemical cycles. Through interagency and international collaborations, and through the organization of dedicated workshops, town hall meetings and presentations at international conferences, the scoping study engages the broader scientific community and invites participation of

CO source contribution analysis for California during ARCTAS-CARB

NASA Astrophysics Data System (ADS)

Pfister, G. G.; Avise, J.; Wiedinmyer, C.; Edwards, D. P.; Emmons, L. K.; Diskin, G. D.; Podolske, J.; Wisthaler, A.

2011-08-01

Air pollution is of concern in many parts of California and is impacted by both local emissions and also by pollution inflow from the North Pacific Ocean. In this study, we use the regional chemical transport model WRF-Chem V3.2 together with the global Model for OZone and Related Chemical Tracers to examine the CO budget over California. We include model CO tracers for different emission sources in the models, which allow estimation of the relative importance of local sources versus pollution inflow on the distribution of CO at the surface and in the free troposphere. The focus of our study is on the 15 June-15 July 2008 time period, which coincides with the aircraft deployment of the NASA Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) mission over California. Model simulations are evaluated using these aircraft observations as well as satellite retrievals and surface observations of CO. Evaluation results show that the model overall predicts the observed CO fields well, but points towards an underestimate of CO from the fires in Northern California, which had a strong influence during the study period, and towards a slight overestimate of CO from pollution inflow and local anthropogenic sources. The analysis of the CO budget over California reveals that inflow of CO explains on average 99 ± 11 ppbV of surface CO during the study period, compared to 61 ± 95 ppbV for local anthropogenic direct emissions of CO and 84 ± 194 ppbV for fires. In the free troposphere, the average CO contributions are estimated as 96 ± 7 ppbV for CO inflow, 8 ± 9 ppbV for CO from local anthropogenic sources and 18 ± 13 ppbV for CO from fires. Accounting for the low bias in the CO fire emission inventory, the fire impact during the study period might have been up to a factor 4 higher than the given estimates.

Investigation of the Aerosols Over the Los Angeles Basin during the ARCTAS-CARB 2008 Pilot Study

NASA Astrophysics Data System (ADS)

Thornhill, L.; Anderson, B. E.; Beyersdorf, A.; Chen, G.; Winstead, E. L.; Lathem, T.; Diskin, G.; Sachse, G.; Dibb, J.; Scheuer, E.

2008-12-01

In the summer of 2008 during preparation for the second phase of the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS), detailed measurements of atmospheric composition were made on-board the NASA DC-8 over the state of California on behalf of the California Air resources Board (CARB). Four flights were conducted between 18 July and 24 July, totaling 31 hours, over southern and central California to establish upwind chemical boundary conditions and gain a better understanding of the sources, chemical characteristics and spatial distribution of smog and greenhouse gases over the state. Serendipitously, from a science perspective, this time period was marked by numerous wildfires spread throughout the state. The DC-8 sensor suite included aerosol instruments capable of measuring the number concentrations, optical properties, and size distributions of aerosols between 0.003 and 20 um in diameter. In this presentation, we will characterize aerosols sampled during sorties over the Los Angeles basin, which included several missed approaches at Los Angeles International Airport (LAX), traverses through the Long Beach and Santa Barbara ship channels, sampling in and out of the marine boundary layer, and encounters with outflow of forest fires mixed with urban smog. We will examine the evolution of the aerosols over the course of the day, as the smog accumulates within the basin and is then transported out of the basin into the surrounding atmosphere.

Pollution impacts on Arctic O3 and CO distributions during POLARCAT summer campaign.

NASA Astrophysics Data System (ADS)

Pommier, M.; Law, K. S.; Clerbaux, C.; Turquety, S.; Schlager, H.; Ancellet, G.; Paris, J.-D.; NASA Arctas Data Team

2009-04-01

The Arctic ozone budget is not well quantified and global models fail to reproduce seasonal cycles especially in summertime when anthropogenic and boreal forest fire emissions can contribute. One possible explanation is the underestimation of modelled ozone production in forest fires plumes. Long-range transport of anthropogenic pollution to the Arctic is also not well quantified. This study focuses on analysis of the POLARCAT summer campaign which took place in Kangerlussuaq, Greenland in July 2008. During the campaign different air masses were sampled including clean northerly air, polluted plumes originating from anthropogenic sources in North American and forest fire plumes from Siberia and Canada. Measurements of O3 and CO collected by the ATR-42 aircraft as part of POLARCAT-France and the German DLR-Falcon aircraft as part of POLARCAT-GRACE are compared to satellite observations from the IASI (Infrared Atmospheric Sounding Interferometer) interferometer. Specific IASI validation flights are also used to validate the measurements. Both in-situ and satellite data are compared to results from the LMDz-INCA global chemistry model. Data from other campaigns such as NASA-ARCTAS and YAK flights in Siberia are also available for these comparisons. Preliminary analyses of Lagrangian matches between aircraft measuring in the same air masses using the CiTTyCAT photochemical trajectory model are presented.

Simulating Aerosol Optical Properties With the Aerosol Simulation Program (ASP): Closure Studies Using ARCTAS Data

NASA Astrophysics Data System (ADS)

Alvarado, M. J.; Macintyre, H. L.; Bian, H.; Chin, M.; Wang, C.

2012-12-01

The scattering and absorption of ultraviolet and visible radiation by aerosols can significantly alter actinic fluxes and photolysis rates. Accurate modeling of aerosol optical properties is thus essential to simulating atmospheric chemistry, air quality, and climate. Here we evaluate the aerosol optical property predictions of the Aerosol Simulation Program (ASP) with in situ data on aerosol scattering and absorption gathered during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) campaign. The model simulations are initialized with in situ data on the aerosol size distribution and composition. We perform a set of sensitivity studies (e.g., internal vs. external mixture, core-in-shell versus Maxwell-Garnett, fraction of the organic carbon mass that is light-absorbing "brown carbon," etc.) to determine the model framework and parameters most consistent with the observations. We compare the ASP results to the aerosol optical property lookup tables in FAST-JX and suggest improvements that will better enable FAST-JX to simulate the impact of aerosols on photolysis rates and atmospheric chemistry.

Siberian and North American Biomass Burning Contributions to the Processes that Influenced the 2008 Arctic Aircraft and Satellite Field Campaigns

NASA Astrophysics Data System (ADS)

Soja, A. J.; Stocks, B. J.; Carr, R.; Pierce, R. B.; Natarajan, M.; Fromm, M.

2009-05-01

Current climate change scenarios predict increases in biomass burning in terms of increases in fire frequency, area burned, fire season length and fire season severity, particularly in boreal regions. Climate and weather control fire danger, which strongly influences the severity of fire events, and these in turn, feed back to the climate system through direct and indirect emissions, modifying cloud condensation nuclei and altering albedo (affecting the energy balance) through vegetative land cover change and deposition. Additionally, fire emissions adversely influence air quality and human health downwind of burning. The boreal zone is significant because this region stores the largest reservoir of terrestrial carbon, globally, and will experience climate change impacts earliest. Boreal biomass burning is an integral component to several of the primary goals of the ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) and ARCPAC (Aerosol, Radiation, and Cloud Processes affecting Arctic Climate) 2008 field campaigns, which include its implication for atmospheric composition and climate, aerosol radiative forcing, and chemical processes with a focus on ozone and aerosols. Both the spring and summer phases of ARCTAS and ARCPAC offered substantial opportunities for sampling fresh and aged biomass burning emissions. However, the extent to which spring biomass burning influenced arctic haze was unexpected, which could inform our knowledge of the formation of arctic haze and the early deposition of black carbon on the icy arctic surface. There is already evidence of increased extreme fire seasons that correlate with warming across the circumboreal zone. In this presentation, we discuss seasonal and annual fire activity and anomalies that relate to the ARCTAS and ARCPAC spring (April 1 - 20) and summer (June 18 - July 13) periods across Siberia and North America, with particular emphasis on fire danger and fire behavior as they relate

Spatio-Temporal Variability of Atmospheric CO2 as Observed from In-Situ Measurements over North America during NASA Field Campaigns (2004-2008)

NASA Technical Reports Server (NTRS)

Choi, Yonghoon; Vay, Stephanie A.; Woo, Jung-Hun; Choi, Kichul; Diskin, Glenn S.; Sachse, G. W.; Vadrevu, Krishna P.; Czech, E.

2009-01-01

Regional-scale measurements were made over the eastern United States (Intercontinental Chemical Transport Experiment - North America (INTEX-NA), summer 2004); Mexico (Megacity Initiative: Local and Global Research Observations (MILAGRO), March 2006); the eastern North Pacific and Alaska (INTEX-B May 2006); and the Canadian Arctic (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS), spring and summer 2008). For these field campaigns, instrumentation for the in situ measurement of CO2 was integrated on the NASA DC-8 research aircraft providing high-resolution (1 second) data traceable to the WMO CO2 mole fraction scale. These observations provide unique and definitive data sets via their intermediate-scale coverage and frequent vertical profiles (0.1 - 12 km) for examining the variability CO2 exhibits above the Earth s surface. A bottom-up anthropogenic CO2 emissions inventory (1deg 1deg) and processing methodology has also been developed for North America in support of these airborne science missions. In this presentation, the spatio-temporal distributions of CO2 and CO column values derived from the campaign measurements will be examined in conjunction with the emissions inventory and transport histories to aid in the interpretation of the CO2 observations.

Toward understanding the role of the atmosphere in pan Arctic change and sea ice loss; an update on the status of focused campaigns under POLARCAT.

NASA Astrophysics Data System (ADS)

Burkhart, J. F.; Bates, T.; Brock, C. A.; Clerbaux, C.; Crawford, J. H.; Dibb, J. E.; Elansky, N.; Ghan, S.; Hirdman, D.; Honrath, R. E.; Jacob, D. J.; Law, K.; Paris, J.; Quinn, P.; Schlager, H.; Singh, H. B.; Sodemann, H.; Stohl, A.

2008-12-01

Sea ice loss reached an extraordinary extent in 2007, decreasing in area more than 2.5 million square kilometres below the 1979 extent. Sea ice loss is one of many Arctic processes resulting from a warming climate. The dynamics of a changing Arctic system are particularly sensitive to climate change and filled with uncertainties and complex feedback mechanisms - most being simply unknown. During the International Polar Year (IPY) a number of international partnerships were formed to establish the Polar Study using Aircraft, Remote Sensing, Surface Measurements and Models, of Climate, Chemistry, Aerosols, and Transport (POLARCAT). Under the umbrella of POLARCAT projects cooperated with national funding to undertake the most comprehensive assessment of air pollution impacts on the Arctic to date. In the spring and summer of 2008 more than 20 institutes from ten nations participated in intensive aircraft, ship, and station-based campaigns with accompanying efforts from the satellite and modelling communities to provide near real time products for mission planning and analysis. The campaigns provided an assessment of the role that tropospheric chemistry, aerosols, and transport play in the Arctic. The spring campaigns focused on anthropogenic pollution, while the summer campaigns targeted biomass burning. During the spring of 2008, over 80 flights were flown by five different aircraft as part of the ARCTAS, ISDAC, ARCPAC, and French POLARCAT campaigns, the ICEALOT campaign commissioned the R/V Knorr to travel over 12,000 km, and numerous specialty satellite and modelling products were developed with near real time distribution. These same products were again used for flight planning and forecasting in the summer when an additional 50+ flights were flown by the ARCTAS, French POLARCAT, Siberian YAK, and GRACE campaigns. Several ground based stations and the Siberian TROICA campaign also conducted intensive operating periods (IOPs). We present an overview of the

Eric Apel and Alan Hills of the National Center for Atmospheric Research install the Trace Organic Gas Analyzer's sensor probe on the exterior of NASA's DC-8

NASA Image and Video Library

2008-03-07

Climate researchers from the National Center for Atmospheric Research (NCAR) and several universities install and perform functional checkouts of a variety of sensitive atmospheric instruments on NASA's DC-8 airborne laboratory prior to beginning the ARCTAS mission.

Arctic Gas Phase Water Vapor Measurements from the NASA DC-8 During SOLVE

NASA Technical Reports Server (NTRS)

Podolske, James; Sachse, Glen; Hipskind, R. Stephen (Technical Monitor)

2000-01-01

The NASA Langley / Ames Diode Laser Hygrometer (DLH) was flown aboard the NASA DC-8 during all three arctic deployments of the SOLVE campaign. The DLH measures gas phase H2O in the freestream air between the fuselage and the outer right engine cowling, essentially free from aircraft perturbations. It uses wavelength-modulated near-IR laser radiation at about 1.4 microns to detect the H2O absorption. Calibration is based on short path experiments in the laboratory using a NIST-traceable dewpoint hygrometer with carefully conditioned air at dewpoints between - 10 and + 10 degrees C. The theory of operation of the DLH instrument will be presented, along with a description of the calibration methodology. A simple climatology of H2O observations from SOLVE will be presented.

Validation of Cloud Optical Parameters from Passive Remote Sensing in the Arctic by using the Aircraft Measurements

NASA Astrophysics Data System (ADS)

Chen, H.; Schmidt, S.; Coddington, O.; Wind, G.; Bucholtz, A.; Segal-Rosenhaimer, M.; LeBlanc, S. E.

2017-12-01

Cloud Optical Parameters (COPs: e.g., cloud optical thickness and cloud effective radius) and surface albedo are the most important inputs for determining the Cloud Radiative Effect (CRE) at the surface. In the Arctic, the COPs derived from passive remote sensing such as from the Moderate Resolution Imaging Spectroradiometer (MODIS) are difficult to obtain with adequate accuracy owing mainly to insufficient knowledge about the snow/ice surface, but also because of the low solar zenith angle. This study aims to validate COPs derived from passive remote sensing in the Arctic by using aircraft measurements collected during two field campaigns based in Fairbanks, Alaska. During both experiments, ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) and ARISE (Arctic Radiation-IceBridge Sea and Ice Experiment), the Solar Spectral Flux Radiometer (SSFR) measured upwelling and downwelling shortwave spectral irradiances, which can be used to derive surface and cloud albedo, as well as the irradiance transmitted by clouds. We assess the variability of the Arctic sea ice/snow surfaces albedo through these aircraft measurements and incorporate this variability into cloud retrievals for SSFR. We then compare COPs as derived from SSFR and MODIS for all suitable aircraft underpasses of the satellites. Finally, the sensitivities of the COPs to surface albedo and solar zenith angle are investigated.

Global View of the Arctic Ocean

NASA Image and Video Library

2000-09-20

NASA researchers have new [sic] insights into the mysteries of Arctic sea ice, thanks to the unique abilities of Canada's Radarsat satellite. The Arctic is the smallest of the world's four oceans, but it may play a large role in helping scientists monitor Earth's climate shifts. Using Radarsat's special sensors to take images at night and to peer through clouds, NASA researchers can now see the complete ice cover of the Arctic. This allows tracking of any shifts and changes, in unprecedented detail, over the course of an entire winter. The radar-generated, high-resolution images are up to 100 times better than those taken by previous satellites. http://photojournal.jpl.nasa.gov/catalog/PIA02970

MISR ARCTAS Products

Atmospheric Science Data Center

2016-11-25

... Remote sensing, surface measurements and modeling of Climate, chemistry, Aerosols and Transport) campaigns for the International Polar Year, is aimed at learning more about the state of the Arctic atmosphere and reporting on the changes that have occurred ...

Analysis of Satellite-Derived Arctic Tropospheric BrO Columns in Conjunction with Aircraft Measurements During ARCTAS and ARCPAC

NASA Technical Reports Server (NTRS)

Choi, S.; Wang, Y.; Salawitch, R. J.; Canty, T.; Joiner, J.; Zeng, T.; Kurosu, T. P.; Chance, K.; Richter, A.; Huey, L. G.;

Arctic Sea Ice

NASA Image and Video Library

2017-12-08

On July 12, 2011, crew from the U.S. Coast Guard Cutter Healy retrieved a canister dropped by parachute from a C-130, which brought supplies for some mid-mission fixes. The ICESCAPE mission, or "Impacts of Climate on Ecosystems and Chemistry of the Arctic Pacific Environment," is NASA's two-year shipborne investigation to study how changing conditions in the Arctic affect the ocean's chemistry and ecosystems. The bulk of the research takes place in the Beaufort and Chukchi seas in summer 2010 and 2011. Credit: NASA/Kathryn Hansen For updates on the five-week ICESCAPE voyage, visit the mission blog at: go.usa.gov/WwU NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Compendium of NASA data base for the Global Tropospheric Experiment's Arctic Boundary Layer Experiments ABLE-3A and ABLE-3B

NASA Technical Reports Server (NTRS)

Gregory, Gerald L.; Scott, A. Donald, Jr.

1994-01-01

The report provides a compendium of NASA aircraft data that are available from NASA's Global Tropospheric Experiment's (GTE) Arctic Boundary Layer Experiments (ABLE) conducted in July and August of 1988 (ABLE-3A) and 1990 (ABLE-3B). ABLE-3A flight experiments were based at Barrow and Bethel, Alaska, and included survey/transit flights to Thule, Greenland. ABLE-3B flight experiments were based at North Bay (Ontario) and Goose Bay, Canada, and included flights northward to Frobisher Bay, Canada. The primary purposes of the experiments were (1) the measurement of the flux of various trace gases from high-arctic ecosystems, (2) the elucidation of factors important to the production and destruction of ozone, and (3) the documentation of source and chemical signature of air common to and transported into the regions. The report provides a representation, in the form of selected data plots, of aircraft data that are available in archived format via NASA Langley's Distributed Active Archive Center. The archived data bases include data for other species measured on the aircraft as well as numerous supporting data, including meteorological observations/products, results from surface studies, satellite observations, and sondes releases.

Approaching the 2015 Arctic Sea Ice Minimum

NASA Image and Video Library

2017-12-08

As the sun sets over the Arctic, the end of this year’s melt season is quickly approaching and the sea ice cover has already shrunk to the fourth lowest in the satellite record. With possibly some days of melting left, the sea ice extent could still drop to the second or third lowest on record. Arctic sea ice, which regulates the planet’s temperature by bouncing solar energy back to space, has been on a steep decline for the last two decades. This animation shows the evolution of Arctic sea ice in 2015, from its annual maximum wintertime extent, reached on February 25, to September 6. Credit: NASA Scientific Visualization Studio DOWNLOAD THIS VIDEO HERE: svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=11999 NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

The Real Time Mission Monitor: A Platform for Real Time Environmental Data Integration and Display during NASA Field Campaigns

NASA Astrophysics Data System (ADS)

He, M.; Hardin, D. M.; Goodman, M.; Blakeslee, R.

2008-05-01

the RTMM will be flown in the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) experiment to study the atmospheric composition in the Arctic.

HFC-152a and HFC-134a emission estimates and characterization of CFCs, CFC replacements, and other halogenated solvents measured during the 2008 ARCTAS campaign (CARB phase) over the South Coast Air Basin of California

NASA Astrophysics Data System (ADS)

Barletta, B.; Nissenson, P.; Meinardi, S.; Dabdub, D.; Sherwood Rowland, F.; Vancuren, R. A.; Pederson, J.; Diskin, G. S.; Blake, D. R.

2011-03-01

This work presents results from the NASA Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) study. Whole air samples were obtained on board research flights that flew over California during June 2008 and analyzed for selected volatile organic compounds, including several halogenated species. Samples collected over the South Coast Air Basin of California (SoCAB), which includes much of Los Angeles (LA) County, were compared with samples from inflow air masses over the Pacific Ocean. The levels of many halocarbon species were enhanced significantly over the SoCAB, including compounds regulated by the Montreal Protocol and subsequent amendments. Emissions estimates of HFC-152a (1,1-difluoroethane, CH3CHF2; 0.82 ± 0.11 Gg) and HFC-134a (1,1,1,2-tetrafluoroethane, CH2FCF3; 1.16 ± 0.22 Gg) in LA County for 2008 were obtained using the observed HFC:carbon monoxide (CO) enhancement ratio. Emission rates also were calculated for the SoCAB (1.60 ± 0.22 Gg yr-1 for HFC-152a and 2.12 ± 0.28 Gg yr-1 for HFC-134a) and then extrapolated to the United States (32 ± 4 Gg yr-1 for HFC-152a and 43 ± 6 Gg yr-1 for HFC-134a) using population data. In addition, emission rates of the two HFCs in LA County and SoCAB were calculated by a second method that utilizes air quality modeling. Emissions estimates obtained using both methods differ by less than 25% for the LA County and less than 45% for the SoCAB.

Global View of the Arctic Ocean

NASA Technical Reports Server (NTRS)

2000-01-01

NASA researchers have new insights into the mysteries of Arctic sea ice, thanks to the unique abilities of Canada's Radarsat satellite. The Arctic is the smallest of the world's four oceans, but it may play a large role in helping scientists monitor Earth's climate shifts.

Using Radarsat's special sensors to take images at night and to peer through clouds, NASA researchers can now see the complete ice cover of the Arctic. This allows tracking of any shifts and changes, in unprecedented detail, over the course of an entire winter. The radar-generated, high-resolution images are up to 100 times better than those taken by previous satellites.

Using this new information, scientists at NASA's Jet Propulsion Laboratory (JPL), Pasadena, Calif., can generate comprehensive maps of Arctic sea ice thickness for the first time. 'Before we knew only the extent of the ice cover,' said Dr. Ronald Kwok, JPL principal investigator of a project called Sea Ice Thickness Derived From High Resolution Radar Imagery. 'We also knew that the sea ice extent had decreased over the last 20 years, but we knew very little about ice thickness.'

'Since sea ice is very thin, about 3 meters (10 feet) or less,'Kwok explained, 'it is very sensitive to climate change.'

Until now, observations of polar sea ice thickness have been available for specific areas, but not for the entire polar region.

The new radar mapping technique has also given scientists a close look at how the sea ice cover grows and contorts over time. 'Using this new data set, we have the first estimates of how much ice has been produced and where it formed during the winter. We have never been able to do this before, ' said Kwok. 'Through our radar maps of the Arctic Ocean, we can actually see ice breaking apart and thin ice growth in the new openings. '

RADARSAT gives researchers a piece of the overall puzzle every three days by creating a complete image of the Arctic. NASA scientists then put those puzzle pieces

Collaboration During the NASA ABoVE Airborne SAR Campaign: Sampling Strategies Used by NGEE Arctic and Other Partners in Alaska and Western Canada

NASA Astrophysics Data System (ADS)

Wullschleger, S. D.; Charsley-Groffman, L.; Baltzer, J. L.; Berg, A. A.; Griffith, P. C.; Jafarov, E. E.; Marsh, P.; Miller, C. E.; Schaefer, K. M.; Siqueira, P.; Wilson, C. J.; Kasischke, E. S.

2017-12-01

There is considerable interest in using L- and P-band Synthetic Aperture Radar (SAR) data to monitor variations in aboveground woody biomass, soil moisture, and permafrost conditions in high-latitude ecosystems. Such information is useful for quantifying spatial heterogeneity in surface and subsurface properties, and for model development and evaluation. To conduct these studies, it is desirable that field studies share a common sampling strategy so that the data from multiple sites can be combined and used to analyze variations in conditions across different landscape geomorphologies and vegetation types. In 2015, NASA launched the decade-long Arctic-Boreal Vulnerability Experiment (ABoVE) to study the sensitivity and resilience of these ecosystems to disturbance and environmental change. NASA is able to leverage its remote sensing strengths to collect airborne and satellite observations to capture important ecosystem properties and dynamics across large spatial scales. A critical component of this effort includes collection of ground-based data that can be used to analyze, calibrate and validate remote sensing products. ABoVE researchers at a large number of sites located in important Arctic and boreal ecosystems in Alaska and western Canada are following common design protocols and strategies for measuring soil moisture, thaw depth, biomass, and wetland inundation. Here we elaborate on those sampling strategies as used in the 2017 summer SAR campaign and address the sampling design and measurement protocols for supporting the ABoVE aerial activities. Plot size, transect length, and distribution of replicates across the landscape systematically allowed investigators to optimally sample a site for soil moisture, thaw depth, and organic layer thickness. Specific examples and data sets are described for the Department of Energy's Next-Generation Ecosystem Experiments (NGEE Arctic) project field sites near Nome and Barrow, Alaska. Future airborne and satellite

Sources and Variability of Aerosols and Aerosol-Cloud Interactions in the Arctic

NASA Astrophysics Data System (ADS)

Liu, H.; Zhang, B.; Taylor, P. C.; Moore, R.; Barahona, D.; Fairlie, T. D.; Chen, G.; Ham, S. H.; Kato, S.

2017-12-01

Arctic sea ice in recent decades has significantly declined. This requires understanding of the Arctic surface energy balance, of which clouds are a major driver. However, the mechanisms for the formation and evolution of clouds in the Arctic and the roles of aerosols therein are highly uncertain. Here we conduct data analysis and global model simulations to examine the sources and variability of aerosols and aerosol-cloud interactions in the Arctic. We use the MERRA-2 reanalysis data (2006-present) from the NASA Global Modeling and Assimilation Office (GMAO) to (1) quantify contributions of different aerosol types to the aerosol budget and aerosol optical depths in the Arctic, (2) ­examine aerosol distributions and variability and diagnose the major pathways for mid-latitude pollution transport to the Arctic, including their seasonal and interannual variability, and (3) characterize the distribution and variability of clouds (cloud optical depth, cloud fraction, cloud liquid and ice water path, cloud top height) in the Arctic. We compare MERRA-2 aerosol and cloud properties with those from C3M, a 3-D aerosol and cloud data product developed at NASA Langley Research Center and merged from multiple A-Train satellite (CERES, CloudSat, CALIPSO, and MODIS) observations. We also conduct perturbation experiments using the NASA GEOS-5 chemistry-climate model (with GOCART aerosol module coupled with two-moment cloud microphysics), and discuss the roles of various types of aerosols in the formation and evolution of clouds in the Arctic.

Estimation of Volume and Freshwater Flux from the Arctic Ocean using SMAP and NCEP CFSv2

NASA Astrophysics Data System (ADS)

Bulusu, S.

2017-12-01

Spatial and temporal monitoring of sea surface salinity (SSS) plays an important role globally and especially over the Arctic Ocean. The Arctic ice melt has led to an influx of freshwater into the Arctic environment, a process that can be observed in SSS. The recently launched NASA's Soil Moisture Active Passive (SMAP) mission is primarily designed for the global monitoring of soil moisture using L- band (1.4GHz) frequency. SMAP also has the capability of measuring SSS and can thus extend the NASA's Aquarius salinity mission (ended June 7, 2015), salinity data record with improved temporal/spatial sampling. In this research an attempt is made to investigate the retrievability of SSS over the Arctic from SMAP satellite. The objectives of this study are to verify the use of SMAP sea surface salinity (and freshwater) variability in the Arctic Ocean and the extent to estimate freshwater, salt and volume flux from the Arctic Ocean. Along with SMAP data we will use NASA's Ice, Cloud,and land Elevation Satellites (ICESat and ICESat-2), and ESA's CryoSat-2, and NASA's Gravity Recovery and Climate Experiment (GRACE) satellites data to estimate ice melt in the Arctic. The preliminary results from SMAP compared well with the NCEP Climate Forecast System version 2 (CFSv2) salinity data in this region capturing patterns fairly well over the Arctic.

IASI carbon monoxide validation over the Arctic during POLARCAT spring and summer campaigns

NASA Astrophysics Data System (ADS)

Pommier, M.; Law, K. S.; Clerbaux, C.; Turquety, S.; Hurtmans, D.; Hadji-Lazaro, J.; Coheur, P.-F.; Schlager, H.; Ancellet, G.; Paris, J.-D.; Nédélec, P.; Diskin, G. S.; Podolske, J. R.; Holloway, J. S.; Bernath, P.

2010-06-01

In this paper, we provide a detailed comparison between carbon monoxide (CO) data measured by the Infrared Atmospheric Sounding Interferometer (IASI)/METOP and aircraft measurements over the Arctic. The CO measurements were obtained during North American campaigns (NASA ARCTAS and NOAA ARCPAC) and European campaigns (POLARCAT-France, POLARCAT-GRACE and YAK-AEROSIB) as part of the International Polar Year (IPY) in spring and summer 2008. During the campaigns different air masses were sampled including clean air, polluted plumes originating from anthropogenic sources in Europe, Asia and North America, and forest fire plumes originating from Siberia and Canada. CO-rich plumes following different transport pathways were captured well by the IASI instrument, illustrated for example by a transport event over the North Pole from Asia on 9 July 2008. The comparison between the IASI CO profiles and aircraft data was achieved by first completing the latter for higher altitudes using a latitudinally dependent climatology of ACE-FTS satellite CO profiles (2004-2009) and by subsequently smoothing the resulting full profiles by the IASI averaging kernels. Proceeding this way, the IASI profiles were shown to be in good agreement with smoothed in situ profiles (with a difference of about 10 ppbv) in spring. In summer, the IASI profiles were higher than the smoothed in situ profiles below 8 km, for all polluted cases. Correlations between IASI and combination ACE-FTS/aircraft derived total columns varied from 0.15 to 0.74 in spring and 0.26 to 0.84 in summer, with better results over the sea in spring (0.73) and over the land in summer (0.69).

How well is black carbon in the Arctic atmosphere captured by models?

NASA Astrophysics Data System (ADS)

Eckhardt, Sabine; Berntsen, Terje; Cherian, Ribu; Daskalakis, Nikos; Heyes, Chris; Hodnebrog, Øivind; Kanakidou, Maria; Klimont, Zbigniew; Law, Kathy; Lund, Marianne; Myhre, Gunnar; Myriokefalitakis, Stelios; Olivie, Dirk; Quaas, Johannes; Quennehen, Boris; Raut, Jean-Christophe; Samset, Bjørn; Schulz, Michael; Skeie, Ragnhild; Stohl, Andreas

2014-05-01

A correct representation of the spatial distribution of aerosols in atmospheric models is essential for realistic simulations of deposition and calculations of radiative forcing. It has been observed that transport of black carbon (BC) into the Arctic and scavenging is sometimes not captured accurately enough in chemistry transport models (CTM) as well as global circulation models (GCM). In this study we determine the discrepancies between measured equivalent BC (EBC) and modeled BC for several Arctic measurement stations as well as for Arctic aircraft campaigns. For this, we use the output of a set of 5 models based on the same emission dataset (ECLIPSE emissions, see eclipse.nilu.no) and evaluate the simulated concentrations at the measurement locations and times. Emissions are separated for different sources such as biomass burning, domestic heating, gas flaring, industry and the transport sector. We focus on the years 2008 and 2009, where many campaigns took place in the framework of the International Polar Year. Arctic stations like Barrow, Alert, Station Nord in Greenland and Zeppelin show a very pronounced winter/spring maximum in BC. While monthly averaged measured EBC values are around 80 ng/m^3, the models severely underestimate this with some models simulating only a small percentage of the observed values. During summer measured concentrations are a magnitude lower, and still underestimated by almost an order of magnitude in some models. However, the best models are correct within a factor of 2 in winter/spring and give realistic concentrations in summer. In order to get information on the vertical profile we used measurements from aircraft campaigns like ARCTAS, ARCPAC and HIPPO. It is found that BC in latitudes below 60 degrees is better captured by the models than BC at higher latitudes, even though it is overestimated at high altitudes. A systematic analysis of the performance of different models is presented. With the dataset we use we capture

Black carbon in the Arctic: How well is it captured by models?

NASA Astrophysics Data System (ADS)

Eckhardt, Sabine

2015-04-01

A correct representation of the spatial distribution of aerosols in atmospheric models is essential for realistic simulations of deposition and calculations of radiative forcing. It has been observed that transport of black carbon (BC) into the Arctic and scavenging is sometimes not captured accurately enough in chemistry transport models (CTM) as well as global circulation models (GCM). In this study we determine the discrepancies between measured equivalent BC (EBC) and modeled BC for several Arctic measurement stations as well as for Arctic aircraft campaigns. For this, we use the output of a set of 11 models based on the same emission dataset (ECLIPSE emissions, see eclipse.nilu.no) and evaluate the simulated concentrations at the measurement locations and times. Emissions are separated for different sources such as biomass burning, domestic heating, gas flaring, industry and the transport sector. We focus on the years 2008 and 2009, where many campaigns took place in the framework of the International Polar Year. Arctic stations like Barrow, Alert, Station Nord in Greenland and Zeppelin show a very pronounced winter/spring maximum in BC. While monthly averaged measured EBC values are around 80 ng/m3, the models severely underestimate this with some models simulating only a small percentage of the observed values. During summer measured concentrations are a magnitude lower, and still underestimated by almost an order of magnitude in some models. However, the best models are with a factor of 2 in winter/spring and realistic concentrations in summer. In order to get information on the vertical profile we used measurements from aircraft campaigns like ARCTAS, ARCPAC and HIPPO. It is found that BC in latitudes below 60 degrees is better captured by the models than BC at higher latitudes, even though it is overestimated at high altitudes. A systematic analysis of the performance of different models is presented. With the dataset we capture remote, polluted and fire

Satellite Shows an "Arctic Blanket" Over the U.S.

NASA Image and Video Library

2017-12-08

View detail image here: bit.ly/1bvJlaN Arctic air has surged into the U.S. pushing into the Southeastern states and dropping high temperatures there into the 20s with colder wind chills. This NOAA GOES-East satellite image was captured at 1445 UTC/9:45 a.m. EST on January 28, and between the clouds and the snow on the ground with cold air overhead, it appears as if much of the U.S. has been covered by an "Arctic Blanket." According to NOAA's National Weather Service (NWS), the Gulf coast states from southern Louisiana east to the Carolinas are facing a wintry mix of precipitation along the southern edge of the Arctic air. Meanwhile, NWS notes that wind chills throughout much of the central and eastern U.S. are in single and negative numbers during the day on January 28. The GOES-East satellite is managed and operated by NOAA. This image was created by the NASA/NOAA GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Md. Rob Gutro NASA's Goddard Space Flight Center Credit: NOAA/NASA GOES Project NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

NASA's Terra Satellite Sees Shadows of Solar Eclipse

NASA Image and Video Library

2015-03-20

During the morning of March 20, 2015, a total solar eclipse was visible from parts of Europe, and a partial solar eclipse from northern Africa and northern Asia. NASA's Terra satellite passed over the Arctic Ocean on March 20 at 10:45 UTC (6:45 a.m. EDT) and captured the eclipse's shadow over the clouds in the Arctic Ocean. Credit: NASA Goddard MODIS Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Satellite Shows an "Arctic Blanket" Over the U.S. [detail

NASA Image and Video Library

2014-01-28

Arctic air has surged into the U.S. pushing into the Southeastern states and dropping high temperatures there into the 20s with colder wind chills. This NOAA GOES-East satellite image was captured at 1445 UTC/9:45 a.m. EST on January 28, and between the clouds and the snow on the ground with cold air overhead, it appears as if much of the U.S. has been covered by an "Arctic Blanket." According to NOAA's National Weather Service (NWS), the Gulf coast states from southern Louisiana east to the Carolinas are facing a wintry mix of precipitation along the southern edge of the Arctic air. Meanwhile, NWS notes that wind chills throughout much of the central and eastern U.S. are in single and negative numbers during the day on January 28. The GOES-East satellite is managed and operated by NOAA. This image was created by the NASA/NOAA GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Md. Rob Gutro NASA's Goddard Space Flight Center Credit: NOAA/NASA GOES Project NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

NASA scientists are flying over Alaska

NASA Image and Video Library

2017-08-29

As part of the Arctic Boreal Vulnerability Experiment (ABoVE), NASA scientists are flying over Alaska and Canada, measuring the elevation of rivers and lakes to study how thawing permafrost affects hydrology in the landscape. This view of was taken from NASA’s DC-8 “flying laboratory” as part of the Active Sensing of CO2 Emissions over Nights, Days and Seasons (ASCENDS) experiment. Scientists on NASA’s Air Surface, Water and Ocean Topography (AirSWOT) mission have been flying over the same location, investigating how water levels in the Arctic landscape change as permafrost thaws. Under typical conditions, the frozen layer of soil keeps water from sinking into the ground and percolating away. As permafrost thaws, the water has new ways to move between rivers and lakes, which can raise or lower the elevation of the bodies of water. These changes in water levels will have effects on Arctic life— plants, animals, and humans—in the near future. Credit: NASA/Peter Griffith NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Comparative Views of Arctic Sea Ice Growth

NASA Technical Reports Server (NTRS)

2000-01-01

NASA researchers have new insights into the mysteries of Arctic sea ice, thanks to the unique abilities of Canada's Radarsat satellite. The Arctic is the smallest of the world's four oceans, but it may play a large role in helping scientists monitor Earth's climate shifts.

Using Radarsat's special sensors to take images at night and to peer through clouds, NASA researchers can now see the complete ice cover of the Arctic. This allows tracking of any shifts and changes, in unprecedented detail, over the course of an entire winter. The radar-generated, high-resolution images are up to 100 times better than those taken by previous satellites.

The two images above are separated by nine days (earlier image on the left). Both images represent an area (approximately 96 by 128 kilometers; 60 by 80 miles)located in the Baufort Sea, north of the Alaskan coast. The brighter features are older thicker ice and the darker areas show young, recently formed ice. Within the nine-day span, large and extensive cracks in the ice cover have formed due to ice movement. These cracks expose the open ocean to the cold, frigid atmosphere where sea ice grows rapidly and thickens.

Using this new information, scientists at NASA's Jet Propulsion Laboratory (JPL), Pasadena, Calif., can generate comprehensive maps of Arctic sea ice thickness for the first time. 'Before we knew only the extent of the ice cover,' said Dr. Ronald Kwok, JPL principal investigator of a project called Sea Ice Thickness Derived From High Resolution Radar Imagery. 'We also knew that the sea ice extent had decreased over the last 20 years, but we knew very little about ice thickness.'

'Since sea ice is very thin, about 3 meters (10 feet) or less,'Kwok explained, 'it is very sensitive to climate change.'

Until now, observations of polar sea ice thickness have been available for specific areas, but not for the entire polar region.

The new radar mapping technique has also given scientists a close look at

An Update on NASA's Arctic Boreal Vulnerability Experiment

NASA Astrophysics Data System (ADS)

Goetz, S. J.; Miller, C. E.; Griffith, P. C.; Larson, E. K.; Kasischke, E. S.; Margolis, H. A.

2016-12-01

ABoVE is a NASA-led field campaign taking place in Alaska and western Canada over the next 8-10 years, with a wide range of interdisciplinary science objectives designed to address the extent to which ecosystems and society are vulnerable, or resilient, to environmental changes underway and expected. The first phase of ABoVE is underway, with a focus on ecosystem dynamics and ecosystem services objectives. Some 45 core and affiliated projects are currently included, and another 10-20 will be added in late 2016 with initiation of the airborne science component. The ABoVE leadership is fostering partnerships with several other major arctic and boreal research, management and policy initiatives. The Science Team is organized around science themes, with Working Groups (WGs) on vegetation, permafrost and hydrology, disturbance, carbon dynamics, wildlife and ecosystem services, and modeling. Despite the disciplinary science WGs, ABoVE research broadly focuses the complex interdependencies and feedbacks across disciplines. Additional WGs focus on airborne science, geospatial products, core variables and standards, and stakeholder engagement - all supplemented by a range of infrastructure activities such as data management, cloud computing, laboratory and field support. Ultimately ABoVE research will improve our understanding of the consequences of environmental changes occurring across the study domain, as well as increase our confidence in making projections of the ecosystem responses and vulnerability to changes taking place both within and outside the domain. ABoVE will also build a lasting legacy of research through an expanded knowledge base, the provision of key datasets archived for a broader network of researchers and resource managers, and the development of data products and knowledge designed to foster decision support and applied research partnerships with broad societal relevance. We will provide a brief status update of ABoVE activities and plans, including

CARVE: The Carbon in Arctic Reservoirs Vulnerability Experiment

NASA Technical Reports Server (NTRS)

Miller, Charles E.; Dinardo, Steven J.

2012-01-01

The Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) is a NASA Earth Ventures (EV-1) investigation designed to quantify correlations between atmospheric and surface state variables for the Alaskan terrestrial ecosystems through intensive seasonal aircraft campaigns, ground-based observations, and analysis sustained over a 5-year mission. CARVE bridges critical gaps in our knowledge and understanding of Arctic ecosystems, linkages between the Arctic hydrologic and terrestrial carbon cycles, and the feedbacks from fires and thawing permafrost. CARVE's objectives are to: (1) Directly test hypotheses attributing the mobilization of vulnerable Arctic carbon reservoirs to climate warming; (2) Deliver the first direct measurements and detailed maps of CO2 and CH4 sources on regional scales in the Alaskan Arctic; and (3) Demonstrate new remote sensing and modeling capabilities to quantify feedbacks between carbon fluxes and carbon cycle-climate processes in the Arctic (Figure 1). We describe the investigation design and results from 2011 test flights in Alaska.

Federal Arctic Research Information Workshop: Workshop proceedings

NASA Astrophysics Data System (ADS)

Geiselman, Joy; Mitchell, Kathryn L.

1991-07-01

The Federal Arctic Research Information Workshop was organized on behalf of the Inter-Agency Arctic Research Policy Committee (IARPC) in order to facilitate the exchange of information on Federal research to fulfill the intent of the Arctic Research and Policy Act of 1984. The workshop was held on 19-21 Mar. 1991, and representatives from Federal agencies were invited to report on recent accomplishments of research and related activities and to exchange information on current and future projects and programs. The various Federal agencies included the Departments of Agriculture, Commerce, Defense, Energy, Health and Human Services, Interior, and Transportation. The Environmental Protection Agency, NASA, National Science Foundation, and the Smithsonian Institution also presented papers.

SEARCH: Study of Environmental Arctic Change-A System-scale, Cross-disciplinary Arctic Research Program

NASA Astrophysics Data System (ADS)

Wiggins, H. V.; Eicken, H.; Fox, S. E.; Search Science Steering Committee

2011-12-01

several panels and working groups, with broad representation of the research community. SEARCH is sponsored by eight U.S. agencies, including: the National Science Foundation (NSF), the National Oceanic and Atmospheric Administration (NOAA), the National Aeronautics and Space Administration (NASA), the Department of Defense (DOD), the Department of Energy (DOE), the Department of the Interior (DOI), the Smithsonian Institution, and the U.S. Department of Agriculture (USDA). The U.S. Arctic Research Commission participates as an agency observer. For further information, please visit the website: http://www.arcus.org/search or contact: Helen V. Wiggins: helen@arcus.org, SEARCH Project Office, Arctic Research Consortium of the U.S. (ARCUS).

Reducing the Impact of Sampling Bias in NASA MODIS and VIIRS Level 3 Satellite Derived IR SST Observations over the Arctic

NASA Astrophysics Data System (ADS)

Minnett, P. J.; Liu, Y.; Kilpatrick, K. A.

2016-12-01

Sea-surface temperature (SST) measurements by satellites in the northern hemisphere high latitudes confront several difficulties. Year-round prevalent clouds, effects near ice edges, and the relative small difference between SST and low-level cloud temperatures lead to a significant loss of infrared observations regardless of the more frequent polar satellite overpasses. Recent research (Liu and Minnett, 2016) identified sampling issues in the Level 3 NASA MODIS SST products when 4km observations are aggregated into global grids at different time and space scales, particularly in the Arctic, where a binary decision cloud mask designed for global data is often overly conservative at high latitudes and results in many gaps and missing data. This under sampling of some Arctic regions results in a warm bias in Level 3 products, likely a result of warmer surface temperature, more distant from the ice edge, being identified more frequently as cloud free. Here we present an improved method for cloud detection in the Arctic using a majority vote from an ensemble of four classifiers trained based on an Alternative Decision Tree (ADT) algorithm (Freund and Mason 1999, Pfahringer et. al. 2001). This new cloud classifier increases sampling of clear pixel by 50% in several regions and generally produces cooler monthly average SST fields in the ice-free Arctic, while still retaining the same error characteristics at 1km resolution relative to in situ observations. SST time series of 12 years of MODIS (Aqua and Terra) and more recently VIIRS sensors are compared and the improvements in errors and uncertainties resulting from better cloud screening for Level 3 gridded products are assessed and summarized.

EOS Aqua AMSR-E Arctic Sea Ice Validation Program: Arctic2003 Aircraft Campaign Flight Report

NASA Technical Reports Server (NTRS)

Cavalieri, D. J.; Markus,T.

2003-01-01

In March 2003 a coordinated Arctic sea ice validation field campaign using the NASA Wallops P-3B aircraft was successfully completed. This campaign was part of the program for validating the Earth Observing System (EOS) Aqua Advanced Microwave Scanning Radiometer (AMSR-E) sea ice products. The AMSR-E, designed and built by the Japanese National Space Development Agency for NASA, was launched May 4, 2002 on the EOS Aqua spacecraft. The AMSR-E sea ice products to be validated include sea ice concentration, sea ice temperature, and snow depth on sea ice. This flight report describes the suite of instruments flown on the P-3, the objectives of each of the seven flights, the Arctic regions overflown, and the coordination among satellite, aircraft, and surface-based measurements. Two of the seven aircraft flights were coordinated with scientists making surface measurements of snow and ice properties including sea ice temperature and snow depth on sea ice at a study area near Barrow, AK and at a Navy ice camp located in the Beaufort Sea. Two additional flights were dedicated to making heat and moisture flux measurements over the St. Lawrence Island polynya to support ongoing air-sea-ice processes studies of Arctic coastal polynyas. The remaining flights covered portions of the Bering Sea ice edge, the Chukchi Sea, and Norton Sound.

Derive Arctic Sea-ice Freeboard and Thickness from NASA's LVIS Observations

NASA Astrophysics Data System (ADS)

Yi, D.; Hofton, M. A.; Harbeck, J.; Cornejo, H.; Kurtz, N. T.

2015-12-01

The sea-ice freeboard and thickness are derived from the six sea-ice flights of NASA's IceBridge Land, Vegetation, and Ice Sensor (LVIS) over the Arctic from 2009 to 2013. The LVIS is an airborne scanning laser altimeter. It can operate at an altitude up to 10 km above the ground and produce a data swath up to 2 km wide with 20-m wide footprints. The laser output wavelength is 1064 nm and pulse repetition rate is 1000 Hz. The LVIS L2 geolocated surface elevation product and Level-1b waveform product (http://nsidc.org/data/ilvis2.html and http://nsidc.org/data/ilvis1b.html) at National Snow and Ice Data Center, USA (NSIDC) are used in this study. The elevations are referenced to a geoid with tides and dynamic atmospheric corrections applied. The LVIS waveforms were fitted with Gaussian curves to calculate pulse width, peak location, pulse amplitude, and signal baseline. For each waveform, the centroid, skewness, kurtosis, and pulse area were also calculated. The waveform parameters were calibrated based on laser off pointing angle and laser channels. Calibrated LVIS waveform parameters show a coherent response to variations in surface features along their ground tracks. These parameters, combined with elevation, can be used to identify leads, enabling the derivation of sea-ice freeboard and thickness without relying upon visual images. Preliminary results show that the elevations in some of the LVIS campaigns may vary with laser incident angle; this can introduce an elevation bias if not corrected. Further analysis of the LVIS data shown that the laser incident angle related elevation bias can be removed empirically. The sea-ice freeboard and thickness results from LVIS are compared with NASA's Airborne Topographic Mapper (ATM) for an April 20, 2010 flight, when both LVIS and ATM sensors were on the same aircraft and made coincidental measurements along repeat ground tracks.

Peculiarities of stochastic regime of Arctic ice cover time evolution over 1987-2014 from microwave satellite sounding on the basis of NASA team 2 algorithm

NASA Astrophysics Data System (ADS)

Raev, M. D.; Sharkov, E. A.; Tikhonov, V. V.; Repina, I. A.; Komarova, N. Yu.

2015-12-01

The GLOBAL-RT database (DB) is composed of long-term radio heat multichannel observation data received from DMSP F08-F17 satellites; it is permanently supplemented with new data on the Earth's exploration from the space department of the Space Research Institute, Russian Academy of Sciences. Arctic ice-cover areas for regions higher than 60° N latitude were calculated using the DB polar version and NASA Team 2 algorithm, which is widely used in foreign scientific literature. According to the analysis of variability of Arctic ice cover during 1987-2014, 2 months were selected when the Arctic ice cover was maximal (February) and minimal (September), and the average ice cover area was calculated for these months. Confidence intervals of the average values are in the 95-98% limits. Several approximations are derived for the time dependences of the ice-cover maximum and minimum over the period under study. Regression dependences were calculated for polynomials from the first degree (linear) to sextic. It was ascertained that the minimal root-mean-square error of deviation from the approximated curve sharply decreased for the biquadratic polynomial and then varied insignificantly: from 0.5593 for the polynomial of third degree to 0.4560 for the biquadratic polynomial. Hence, the commonly used strictly linear regression with a negative time gradient for the September Arctic ice cover minimum over 30 years should be considered incorrect.

SEARCH: Study of Environmental Arctic Change—A System-scale, Cross-disciplinary Arctic Research Program

NASA Astrophysics Data System (ADS)

Wiggins, H. V.; Eicken, H.; Fox, S. E.; Search Science Steering Committee

2010-12-01

The Study of Environmental Arctic Change (SEARCH) is a multi-agency effort to understand system-scale arctic change. Interrelated environmental changes in the Arctic are affecting ecosystems and living resources and are impacting local and global communities. The SEARCH program is guided by the Science Steering Committee (SSC), the Interagency Program Management Committee (IPMC), and focused panels. Over 150 projects and activities contribute to SEARCH implementation. The Observing Change component is underway through the National Science Foundation’s (NSF) Arctic Observing Network (AON), NOAA-sponsored atmospheric and sea ice observations, and other relevant national and international efforts. The Understanding Change component of SEARCH consists of modeling and analysis efforts, with strong linkages to relevant programs such as NSF’s Arctic System Science (ARCSS) Program. The SEARCH Sea Ice Outlook (http://www.arcus.org/search/seaiceoutlook/index.php) is an "Understanding Change" synthesis effort that aims to advance our understanding of the arctic sea ice system. The Responding to Change element currently includes initial planning efforts by the International Study of Arctic Change (ISAC) program as well as a newly-launched "Sea Ice for Walrus Outlook," which is a weekly report of sea ice conditions geared to Alaska Native walrus subsistence hunters, coastal communities, and others interested in sea ice and walrus (http://www.arcus.org/search/siwo). SEARCH is sponsored by eight U.S. agencies, including: the National Science Foundation (NSF), the National Oceanic and Atmospheric Administration (NOAA), the National Aeronautics and Space Administration (NASA), the Department of Defense (DOD), the Department of Energy (DOE), the Department of the Interior (DOI), the Smithsonian Institution, and the U.S. Department of Agriculture (USDA). The U.S. Arctic Research Commission participates as an IPMC observer. For further information, please visit the website: http

NASA’s Aerial Survey of Polar Ice Expands Its Arctic Reach

NASA Image and Video Library

2017-12-08

For the past eight years, Operation IceBridge, a NASA mission that conducts aerial surveys of polar ice, has produced unprecedented three-dimensional views of Arctic and Antarctic ice sheets, providing scientists with valuable data on how polar ice is changing in a warming world. Now, for the first time, the campaign will expand its reach to explore the Arctic’s Eurasian Basin through two research flights based out of Svalbard, a Norwegian archipelago in the northern Atlantic Ocean. More: go.nasa.gov/2ngAxX2 Caption: Ellesmere Island mountain tops bathed in light as the sun began to peak over the horizon during Operation IceBridge’s first flight of its 2017 Arctic campaign, on March 9, 2017. Credits: NASA/Nathan Kurtz NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

SEARCH: Study of Environmental Arctic Change—A System-scale, Cross-disciplinary Arctic Research Program

NASA Astrophysics Data System (ADS)

Wiggins, H. V.; Eicken, H.; Fox, S. E.

2012-12-01

permafrost, land ice and sea level, and societal and policy implications. Together, the goals will provide significant insight into arctic system change as a whole. The SEARCH SSC will release the goals in their revised form and then work closely with agency representatives to implement the goals through research opportunities and community activities. SEARCH is guided by a Science Steering Committee and several panels and working groups, with broad representation of the research community. SEARCH is sponsored by eight U.S. agencies, including: the National Science Foundation (NSF), the National Oceanic and Atmospheric Administration (NOAA), the National Aeronautics and Space Administration (NASA), the Department of Defense (DOD), the Department of Energy (DOE), the Department of the Interior (DOI), the Smithsonian Institution, and the U.S. Department of Agriculture (USDA). The U.S. Arctic Research Commission participates as an agency observer. For further information, please visit the website: http://www.arcus.org/search or contact: Helen V. Wiggins: helen@arcus.org, SEARCH Project Office, Arctic Research Consortium of the U.S. (ARCUS).

Four-dimensional variational inversion of black carbon emissions during ARCTAS-CARB with WRFDA-Chem

NASA Astrophysics Data System (ADS)

Guerrette, Jonathan J.; Henze, Daven K.

2017-06-01

Biomass burning emissions of atmospheric aerosols, including black carbon, are growing due to increased global drought, and comprise a large source of uncertainty in regional climate and air quality studies. We develop and apply new incremental four-dimensional variational (4D-Var) capabilities in WRFDA-Chem to find optimal spatially and temporally distributed biomass burning (BB) and anthropogenic black carbon (BC) aerosol emissions. The constraints are provided by aircraft BC concentrations from the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites in collaboration with the California Air Resources Board (ARCTAS-CARB) field campaign and surface BC concentrations from the Interagency Monitoring of PROtected Visual Environment (IMPROVE) network on 22, 23, and 24 June 2008. We consider three BB inventories, including Fire INventory from NCAR (FINN) v1.0 and v1.5 and Quick Fire Emissions Database (QFED) v2.4r8. On 22 June, aircraft observations are able to reduce the spread between a customized QFED inventory and FINNv1.0 from a factor of 3. 5 ( × 3. 5) to only × 2. 1. On 23 and 24 June, the spread is reduced from × 3. 4 to × 1. 4. The posterior corrections to emissions are heterogeneous in time and space, and exhibit similar spatial patterns of sign for both inventories. The posterior diurnal BB patterns indicate that multiple daily emission peaks might be warranted in specific regions of California. The US EPA's 2005 National Emissions Inventory (NEI05) is used as the anthropogenic prior. On 23 and 24 June, the coastal California posterior is reduced by × 2, where highway sources dominate, while inland sources are increased near Barstow by × 5. Relative BB emission variances are reduced from the prior by up to 35 % in grid cells close to aircraft flight paths and by up to 60 % for fires near surface measurements. Anthropogenic variance reduction is as high as 40 % and is similarly limited to sources close to observations. We

SEARCH: Study of Environmental Arctic Change--A System-scale, Cross-disciplinary, Long-term Arctic Research Program

NASA Astrophysics Data System (ADS)

Wiggins, H. V.; Schlosser, P.; Loring, A. J.; Warnick, W. K.; Committee, S. S.

2008-12-01

The Study of Environmental Arctic Change (SEARCH) is a multi-agency effort to observe, understand, and guide responses to changes in the arctic system. Interrelated environmental changes in the Arctic are affecting ecosystems and living resources and are impacting local and global communities and economic activities. Under the SEARCH program, guided by the Science Steering Committee (SSC), the Interagency Program Management Committee (IPMC), and the Observing, Understanding, and Responding to Change panels, scientists with a variety of expertise--atmosphere, ocean and sea ice, hydrology and cryosphere, terrestrial ecosystems, human dimensions, and paleoclimatology--work together to achieve goals of the program. Over 150 projects and activities contribute to SEARCH implementation. The Observing Change component is underway through National Science Foundation's (NSF) Arctic Observing Network (AON), NOAA-sponsored atmospheric and sea ice observations, and other relevant national and international efforts, including the EU- sponsored Developing Arctic Modelling and Observing Capabilities for Long-term Environmental Studies (DAMOCLES) Program. The Understanding Change component of SEARCH consists of modeling and analysis efforts, with strong linkages to relevant programs such as NSF's Arctic System Synthesis (ARCSS) Program. The Responding to Change element is driven by stakeholder research and applications addressing social and economic concerns. As a national program under the International Study of Arctic Change (ISAC), SEARCH is also working to expand international connections in an effort to better understand the global arctic system. SEARCH is sponsored by eight (8) U.S. agencies, including: the National Science Foundation (NSF), the National Oceanic and Atmospheric Administration (NOAA), the National Aeronautics and Space Administration (NASA), the Department of Defense (DOD), the Department of Energy (DOE), the Department of the Interior (DOI), the Smithsonian

Warm Rivers Play Role in Arctic Sea Ice Melt

NASA Image and Video Library

2014-03-05

Beaufort Sea surface temperatures where Canada Mackenzie River discharges into the Arctic Ocean, measured by NASA MODIS instrument; warm river waters had broken through a shoreline sea ice barrier to enhance sea ice melt.

IASI carbon monoxide validation over the Arctic during POLARCAT spring and summer campaigns

NASA Astrophysics Data System (ADS)

Pommier, M.; Law, K. S.; Clerbaux, C.; Turquety, S.; Hurtmans, D.; Hadji-Lazaro, J.; Coheur, P.-F.; Schlager, H.; Ancellet, G.; Paris, J.-D.; Nédélec, P.; Diskin, G. S.; Podolske, J. R.; Holloway, J. S.; Bernath, P.

2010-11-01

In this paper, we provide a detailed comparison between carbon monoxide (CO) data measured by the Infrared Atmospheric Sounding Interferometer (IASI)/MetOp and aircraft observations over the Arctic. The CO measurements were obtained during North American (NASA ARCTAS and NOAA ARCPAC) and European campaigns (POLARCAT-France, POLARCAT-GRACE and YAK-AEROSIB) as part of the International Polar Year (IPY) POLARCAT activity in spring and summer 2008. During the campaigns different air masses were sampled including clean air, polluted plumes originating from anthropogenic sources in Europe, Asia and North America, and forest fire plumes originating from Siberia and Canada. The paper illustrates that CO-rich plumes following different transport pathways were well captured by the IASI instrument, in particular due to the high spatial coverage of IASI. The comparison between IASI CO total columns, 0-5 km partial columns and profiles with collocated aircraft data was achieved by taking into account the different sensitivity and geometry of the sounding instruments. A detailed analysis is provided and the agreement is discussed in terms of information content and surface properties at the location of the observations. For profiles, the data were found to be in good agreement in spring with differences lower than 17%, whereas in summer the difference can reach 20% for IASI profiles below 8 km for polluted cases. For total columns the correlation coefficients ranged from 0.15 to 0.74 (from 0.47 to 0.77 for partial columns) in spring and from 0.26 to 0.84 (from 0.66 to 0.88 for partial columns) in summer. A better agreement is seen over the sea in spring (0.73 for total column and 0.78 for partial column) and over the land in summer (0.69 for total columns and 0.81 for partial columns). The IASI vertical sensitivity was better over land than over sea, and better over land than over sea ice and snow allowing a higher potential to detect CO vertical distribution during summer.

Arctic Observing Experiment (AOX) Field Campaign Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rigor, Ignatius; Johnson, Jim; Motz, Emily

Our ability to understand and predict weather and climate requires an accurate observing network. One of the pillars of this network is the observation of the fundamental meteorological parameters: temperature, air pressure, and wind. We plan to assess our ability to measure these parameters for the polar regions during the Arctic Observing Experiment (AOX, Figure 1) to support the International Arctic Buoy Programme (IABP), Arctic Observing Network (AON), International Program for Antarctic Buoys (IPAB), and Southern Ocean Observing System (SOOS). Accurate temperature measurements are also necessary to validate and improve satellite measurements of surface temperature across the Arctic. Support formore » research associated with the campaign is provided by the National Science Foundation, and by other US agencies contributing to the US Interagency Arctic Buoy Program. In addition to the support provided by the U.S Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility’s North Slope of Alaska (NSA) site at Barrow and the National Science Foundation (NSF), the U.S. IABP is supported by the U.S. Coast Guard (USCG), the National Aeronautics and Space Administration (NASA), the National Ice Center (NIC), the National Oceanic and Atmospheric Administration (NOAA), and the Office of Naval Research (ONR).« less

The Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE): Examining the complex Arctic biological-climatologic-hydrologic system

NASA Astrophysics Data System (ADS)

McDonald, K. C.; Podest, E.; Miller, C. E.; Dinardo, S. J.

2012-12-01

Fundamental aspects of the complex Arctic biological-climatologic-hydrologic system remain poorly quantified. As a result, significant uncertainties exist in the carbon budget of the Arctic ecosystem. NASA's Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) is a currently-operational Earth Venture 1 (EV-1) mission that is examining correlations between atmospheric and surface state variables for the Alaskan terrestrial ecosystems. CARVE is conducted through a series of intensive seasonal aircraft campaigns, ground-based observations, and analysis sustained over a 5-year mission timeframe. CARVE employs a C-23 Sherpa aircraft to fly an innovative airborne remote sensing payload. This payload includes an L-band radiometer/radar system and a nadir-viewing spectrometer to deliver simultaneous measurements of land surface state variables that control gas emissions (i.e., soil moisture and inundation, freeze/thaw state, surface temperature) and total atmospheric columns of carbon dioxide, methane, and carbon monoxide. The aircraft payload also includes a gas analyzer that links greenhouse gas measurements directly to World Meteorological Organization standards and provide vertical profile information. CARVE measurement campaigns are scheduled regularly throughout the growing season each year to capture the seasonal variability in Arctic system carbon fluxes associated with the spring thaw, the summer drawdown, and the fall refreeze. Continuous ground-based measurements provide temporal and regional context as well as calibration for CARVE airborne measurements. CARVE bridges critical gaps in our knowledge and understanding of Arctic ecosystems, linkages between the Arctic hydrologic and terrestrial carbon cycles, and the feedbacks from fires and thawing permafrost. Ultimately, CARVE will provide an integrated set of data that will provide unprecedented experimental insights into Arctic carbon cycling. Portions of this work were carried out at the Jet

SEARCH: Study of Environmental Arctic Change--A System-scale, Cross-disciplinary, Long-term Arctic Research Program

NASA Astrophysics Data System (ADS)

Wiggins, H. V.; Schlosser, P.; Fox, S. E.

2009-12-01

Administration (NASA), the Department of Defense (DOD), the Department of Energy (DOE), the Department of the Interior (DOI), the Smithsonian Institution, and the U.S. Department of Agriculture (USDA). The U.S. Arctic Research Commission (USARC) participates as an IPMC observer. For more information, visit the website at: http://www.arcus.org/search or contact: Helen V. Wiggins: helen@arcus.org, SEARCH Project Office, ARCUS; or Peter Schlosser, schlosser@ldeo.columbia.edu, SEARCH SSC Chair.

Intra- and Inter- annual PM2.5 variations in the Arctic region during 2003-2017 based on the NASA's MERRA-2 re-analysis data

NASA Astrophysics Data System (ADS)

Yasunari, T. J.; Kim, K. M.; da Silva, A. M., Jr.

2017-12-01

We examined the intra- and inter-annual variations of PM2.5 in the Arctic region based on monthly mean aerosols (dust, sulfate, sea salt, and carbonaceous aerosols) and PM2.5 from NASA's latest reanalysis, MERRA2. We focus on the time period from January 2003 to the recent month (May 2017). The domain of the Arctic region was defined as North of 66.5N in this study. Although there are some exceptions, the largest contributions of dust, ammonium sulfate, sea salt, and carbonaceous aerosols (i.e., Black Carbon, BC, and Particulate Organic Matter, POM) to the fractions of PM2.5 were mainly seen in spring, spring, fall, and summer, respectively. During the focused time period, the fractions of dust, ammonium sulfate, sea salt, BC, and POM explains 2.7-42.5%, 9.5-37.5%, 16.7-73.1%, 0.5-2.8%, 1.5-58.0% of the Arctic PM2.5, respectively. If we picked up the top 10 high PM2.5 months during the period, those were separated into two seasons: summer (eight months) and winter (two months). For the composites of the summer months above, the areas with higher PM2.5 were Siberia, Far East, Alaska, and Canada and the regions where POM fractions were larger, implying the contributions from smokes due to active wildfires in summer seasons. For the winter months, the mixture of increased dust, ammonium sulfate, and sea salt was seen. However, the highest PM2.5 in the Arctic region was seen from the Kara Sea, Barents Sea, and Greenland Sea over which the contribution of sea salt was very large. This means the sea salt aerosols were the main contributor to the high PM2.5 winter months there. Based on our MERRA-2 analyses, continuous monitoring and development for better forecasting wildfire activities in summer and sea salt emissions in winter would be the keys for better understanding of the air quality in the Arctic region including mitigation and measures of it in the future.

Observations of Hydration and Dehydration in the Winter 2000 Arctic Stratosphere

NASA Technical Reports Server (NTRS)

Herman, R.; Webster, C.; Ordla, K.; Bui, P.; Gandrud, B.

2000-01-01

During the January 2000 deployment of the SAGE III Ozone Loss Validation Experiment (SOLVE), the NASA ER-2 aircraft intercepted air parcels with unusual water mixing ratios within the the Arctic polar vortex.

Airborne Arctic Stratospheric Expedition II: An overview

NASA Astrophysics Data System (ADS)

Anderson, James G.; Toon, Owen B.

1993-11-01

The sudden onset of ozone depletion in the antarctic vortex set a precedent for both the time scale and the severity of global change. The Airborne Antarctic Ozone Experiment (AAOE), staged from Punta Arenas, Chile, in 1987, established that CFCs, halons, and methyl bromide, the dominant sources of chlorine and bromine radicals in the stratosphere, control the rate of ozone destruction over the Antarctic; that the vortex is depleted in reactive nitrogen and water vapor; and that diabatic cooling during the Antarctic winter leads to subsidence within the vortex core, importing air from higher altitudes and lower latitudes. This last conclusion is based on observed dramatic distortion in the tracer fields, most notably N2O.In 1989, the first Airborne Arctic Stratospheric Expedition (AASE-I), staged from Stavanger, Norway, and using the same aircraft employed for AAOE (the NASA ER-2 and the NASA DC-8), discovered that while NOx and to some degree NOy were perturbed within the arctic vortex, there was little evidence for desiccation. Under these (in contrast to the antarctic) marginally perturbed conditions, however, ClO was found to be dramatically enhanced such that a large fraction of the available (inorganic) chlorine resided in the form of ClO and its dimer ClOOCl.This leaves two abiding issues for the northern hemisphere and the mission of the second Airborne Arctic Stratospheric Expedition (AASE-II): (1) Will significant ozone erosion occur within the arctic vortex in the next ten years as chlorine loading in the stratosphere exceeds four parts per billion by volume? (2) Which mechanisms are responsible for the observed ozone erosion poleward of 30°N in the winter/spring northern hemisphere reported in satellite observations?

Warm Rivers Play Role in Arctic Sea Ice Melt Animation

NASA Image and Video Library

2014-03-05

This frame from a NASA MODIS animation depicts warming sea surface temperatures in the Arctic Beaufort Sea after warm waters from Canada Mackenzie River broke through a shoreline sea ice barrier in summer 2012, enhancing the melting of sea ice.

The Arctic Observing Viewer (AOV): Visualization, Data Discovery, Strategic Assessment, and Decision Support for Arctic Observing

NASA Astrophysics Data System (ADS)

Kassin, A.; Cody, R. P.; Barba, M.; Escarzaga, S. M.; Villarreal, S.; Manley, W. F.; Gaylord, A. G.; Habermann, T.; Kozimor, J.; Score, R.; Tweedie, C. E.

2017-12-01

To better assess progress in Arctic Observing made by U.S. SEARCH, NSF AON, SAON, and related initiatives, an updated version of the Arctic Observing Viewer (AOV; http://ArcticObservingViewer.org) has been released. This web mapping application and information system conveys the who, what, where, and when of "data collection sites" - the precise locations of monitoring assets, observing platforms, and wherever repeat marine or terrestrial measurements have been taken. Over 13,000 sites across the circumarctic are documented including a range of boreholes, ship tracks, buoys, towers, sampling stations, sensor networks, vegetation plots, stream gauges, ice cores, observatories, and more. Contributing partners are the U.S. NSF, NOAA, the NSF Arctic Data Center, ADIwg, AOOS, a2dc, CAFF, GINA, IASOA, INTERACT, NASA ABoVE, and USGS, among others. Users can visualize, navigate, select, search, draw, print, view details, and follow links to obtain a comprehensive perspective of environmental monitoring efforts. We continue to develop, populate, and enhance AOV. Recent updates include: a vastly improved Search tool with free text queries, autocomplete, and filters; faster performance; a new clustering visualization; heat maps to highlight concentrated research; and 3-D represented data to more easily identify trends. AOV is founded on principles of interoperability, such that agencies and organizations can use the AOV Viewer and web services for their own purposes. In this way, AOV complements other distributed yet interoperable cyber resources and helps science planners, funding agencies, investigators, data specialists, and others to: assess status, identify overlap, fill gaps, optimize sampling design, refine network performance, clarify directions, access data, coordinate logistics, and collaborate to meet Arctic Observing goals. AOV is a companion application to the Arctic Research Mapping Application (armap.org), which is focused on general project information at a

Lidar measurements of ozone and aerosol distributions during the 1992 airborne Arctic stratospheric expedition

NASA Technical Reports Server (NTRS)

Browell, Edward V.; Butler, Carolyn F.; Fenn, Marta A.; Grant, William B.; Ismail, Syed; Carter, Arlen F.

1994-01-01

The NASA Langley airborne differential absorption lidar system was operated from the NASA Ames DC-8 aircraft during the 1992 Airborne Arctic Stratospheric Expedition to investigate the distribution of stratospheric aerosols and ozone (O3) across the Arctic vortex from January to March 1992. Aerosols from the Mt. Pinatubo eruption were found outside and inside the Arctic vortex with distinctly different scattering characteristics and spatial distributions in the two regions. The aerosol and O3 distributions clearly identified the edge of the vortex and provided additional information on vortex dynamics and transport processes. Few polar stratospheric clouds were observed during the AASE-2; however, those that were found had enhanced scattering and depolarization over the background Pinatubo aerosols. The distribution of aerosols inside the vortex exhibited relatively minor changes during the AASE-2. Ozone depletion inside the vortex as limited to less than or equal to 20 percent in the altitude region from 15-20 km.

Reconstruction of Arctic surface temperature in past 100 years using DINEOF

NASA Astrophysics Data System (ADS)

Zhang, Qiyi; Huang, Jianbin; Luo, Yong

2015-04-01

Global annual mean surface temperature has not risen apparently since 1998, which is described as global warming hiatus in recent years. However, measuring of temperature variability in Arctic is difficult because of large gaps in coverage of Arctic region in most observed gridded datasets. Since Arctic has experienced a rapid temperature change in recent years that called polar amplification, and temperature risen in Arctic is faster than global mean, the unobserved temperature in central Arctic will result in cold bias in both global and Arctic temperature measurement compared with model simulations and reanalysis datasets. Moreover, some datasets that have complete coverage in Arctic but short temporal scale cannot show Arctic temperature variability for long time. Data Interpolating Empirical Orthogonal Function (DINEOF) were applied to fill the coverage gap of NASA's Goddard Institute for Space Studies Surface Temperature Analysis (GISTEMP 250km smooth) product in Arctic with IABP dataset which covers entire Arctic region between 1979 and 1998, and to reconstruct Arctic temperature in 1900-2012. This method provided temperature reconstruction in central Arctic and precise estimation of both global and Arctic temperature variability with a long temporal scale. Results have been verified by extra independent station records in Arctic by statistical analysis, such as variance and standard deviation. The result of reconstruction shows significant warming trend in Arctic in recent 30 years, as the temperature trend in Arctic since 1997 is 0.76°C per decade, compared with 0.48°C and 0.67°C per decade from 250km smooth and 1200km smooth of GISTEMP. And global temperature trend is two times greater after using DINEOF. The discrepancies above stress the importance of fully consideration of temperature variance in Arctic because gaps of coverage in Arctic cause apparent cold bias in temperature estimation. The result of global surface temperature also proves that

Monitoring the Arctic during Polar Darkness

NASA Image and Video Library

2017-12-08

Image acquired October 30, 2012 Scientists watched the Arctic with particular interest in the summer of 2012, when Arctic sea ice set a new record low. The behavior of sea ice following such a low extent also interests scientists, but as Arctic sea ice was advancing in the autumn of 2012, so was polar darkness. Fortunately, the Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi NPP satellite can see in the dark. The VIIRS “day-night band” detects light in a range of wavelengths from green to near-infrared and uses filtering techniques to observe signals such as gas flares, auroras, wildfires, city lights, and reflected moonlight. VIIRS acquired this nighttime view of sea ice north of Russia and Alaska on October 30, 2012. The day-night band takes advantage of moonlight, airglow (the atmosphere’s self-illumination through chemical reactions), zodiacal light (sunlight scattered by interplanetary dust), and starlight from the Milky Way. By using these dim light sources, the day-night band can detect changes in clouds, snow cover, and sea ice. The VIIRS day-night band offers a unique perspective because once polar night has descended, satellite sensors relying on visible light can no longer produce photo-like images. And although passive microwave sensors can monitor sea ice through the winter, they offer much lower resolution. Steve Miller of the Cooperative Institute for Research in the Atmosphere at Colorado State University has used the day-night band to study nighttime behavior of weather systems and sees advantages in studying the polar regions. “There’s a lot of use with these measurements as we look back at a season of record ice melt in the Arctic,” Miller says. “We can observe areas where there is ice melt and reformation, where there’s clear water and ships can pass through—especially as the ‘great darkness’ approaches with winter.” Ted Scambos of the National Snow and Ice Data Center at the University of Colorado concurs

Arctic Sea Ice Sets New Record Winter Low

NASA Image and Video Library

2015-03-19

The sea ice cap of the Arctic appeared to reach its annual maximum winter extent on February 25, according to data from the NASA-supported National Snow and Ice Data Center (NSIDC) at the University of Colorado, Boulder. At 5.61 million square miles (14.54 million square kilometers), this year’s maximum extent was the smallest on the satellite record and also one of the earliest. Credit: NASA Goddard Space Flight Center NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

IHY-IPY conference report from Polar Gateways Arctic Circle Sunrise 2008

NASA Astrophysics Data System (ADS)

Cooper, John; Kauristie, Kirsti; Weatherwax, Allan; Thompson, Barbara; Sheehan, Glenn; Smith, Roger; Sandahl, Ingrid

Polar, heliophysical, and planetary science topics related to the International Heliophysical and Polar Years 2007-2009 were addressed during this unique circumpolar conference hosted January 23-29, 2008 at the new Barrow Arctic Research Center of the Barrow Arctic Science Consortium in Barrow, Alaska. Science presentations spanned the solar system from the polar Sun and heliospheric environment to Earth, Moon, Mars, Jupiter, Saturn, the Kuiper Belt, and the solar wind termination shock now crossed by both Voyager spacecraft. Many of the science presentations were made remotely via video conference or teleconference from Sweden, Norway, Russia, Canada, Antarctica, and the United States, spanning up to thirteen time zones (Alaska to Russia) at various times during the conference. U.S. remote contributions came from the University of Alaska at Fairbanks, the University of California at Berkeley, the University of Arizona, NASA Jet Propulsion Laboratory, and NASA Goddard Space Flight Center. Convening during the first week of 2008 Arctic sunrise at Barrow, this conference served as a prelude that year to international Sun-Earth Day celebrations for IHY, while also commemorating Barrow scientific and native cultural support for the first International Polar Year 1882-1883. Extensive educational outreach activities were conducted with the local Barrow and Alaska North Slope communities and through the NASA Digital Learning Network live from the "top of the world" at Barrow. The conference proceedings are Internet accessible via the home page at http://polargateways2008.org/.

The Importance of Earth Observations and Data Collaboration within Environmental Intelligence Supporting Arctic Research

NASA Technical Reports Server (NTRS)

Casas, Joseph

2017-01-01

Within the IARPC Collaboration Team activities of 2016, Arctic in-situ and remote earth observations advanced topics such as :1) exploring the role for new and innovative autonomous observing technologies in the Arctic; 2) advancing catalytic national and international community based observing efforts in support of the National Strategy for the Arctic Region; and 3) enhancing the use of discovery tools for observing system collaboration such as the U.S. National Oceanic and Atmospheric Administration (NOAA) Arctic Environmental Response Management Application (ERMA) and the U.S. National Aeronautics and Space Administration (NASA) Arctic Collaborative Environment (ACE) project geo reference visualization decision support and exploitation internet based tools. Critical to the success of these earth observations for both in-situ and remote systems is the emerging of new and innovative data collection technologies and comprehensive modeling as well as enhanced communications and cyber infrastructure capabilities which effectively assimilate and dissemination many environmental intelligence products in a timely manner. The Arctic Collaborative Environment (ACE) project is well positioned to greatly enhance user capabilities for accessing, organizing, visualizing, sharing and producing collaborative knowledge for the Arctic.

Arctic Landscape Within Reach

NASA Technical Reports Server (NTRS)

2008-01-01

This image, one of the first captured by NASA's Phoenix Mars Lander, shows flat ground strewn with tiny pebbles and marked by small-scale polygonal cracking, a pattern seen widely in Martian high latitudes and also observed in permafrost terrains on Earth. The polygonal cracking is believed to have resulted from seasonal contraction and expansion of surface ice.

Phoenix touched down on the Red Planet at 4:53 p.m. Pacific Time (7:53 p.m. Eastern Time), May 25, 2008, in an arctic region called Vastitas Borealis, at 68 degrees north latitude, 234 degrees east longitude.

This image was acquired at the Phoenix landing site by the Surface Stereo Imager on day 1 of the mission on the surface of Mars, or Sol 0, after the May 25, 2008, landing.

The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

Characterizing Arctic Sea Ice Topography Using High-Resolution IceBridge Data

NASA Technical Reports Server (NTRS)

Petty, Alek; Tsamados, Michel; Kurtz, Nathan; Farrell, Sinead; Newman, Thomas; Harbeck, Jeremy; Feltham, Daniel; Richter-Menge, Jackie

2016-01-01

We present an analysis of Arctic sea ice topography using high resolution, three-dimensional, surface elevation data from the Airborne Topographic Mapper, flown as part of NASA's Operation IceBridge mission. Surface features in the sea ice cover are detected using a newly developed surface feature picking algorithm. We derive information regarding the height, volume and geometry of surface features from 2009-2014 within the Beaufort/Chukchi and Central Arctic regions. The results are delineated by ice type to estimate the topographic variability across first-year and multi-year ice regimes.

Summer in the Arctic National Wildlife Refuge

NASA Technical Reports Server (NTRS)

2001-01-01

-60 kilometers, arctic tundra dominates the coastal plain, until reaching the foothills of the Brooks Mountain Range. Beneath the tundra, a layer of permafrost reaches an average depth of 600 meters, restricting water drainage through the soil, and increasing the sensitivity of tundra vegetation to disturbance. Precipitation is scarce (less than 16 centimeters per year) and the small amount of melt water or rain that soaks into the tundra remains near the surface. This is why the coastal plain can be classified as a wetland.

The western boundary of the Refuge is marked by the Canning River, about halfway between the center and left-hand side of the image, and the eastern boundary is near the right-hand edge at the US/Canadian border. The two permanent human settlements within the image area are Kaktovic near the tip of the large rounded peninsula, and Arctic Village south of the Brooks Range near the southern Refuge boundary. The area represented by the image is approximately 380 kilometers x 540 kilometers.

MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.

Time-dependence of sea-ice concentration and multiyear ice fraction in the Arctic Basin

USGS Publications Warehouse

Gloersen, P.; Zwally, H.J.; Chang, A.T.C.; Hall, D.K.; Campbell, W.J.; Ramseier, R.O.

1978-01-01

The time variation of the sea-ice concentration and multiyear ice fraction within the pack ice in the Arctic Basin is examined, using microwave images of sea ice recently acquired by the Nimbus-5 spacecraft and the NASA CV-990 airborne laboratory. The images used for these studies were constructed from data acquired from the Electrically Scanned Microwave Radiometer (ESMR) which records radiation from earth and its atmosphere at a wavelength of 1.55 cm. Data are analyzed for four seasons during 1973-1975 to illustrate some basic differences in the properties of the sea ice during those times. Spacecraft data are compared with corresponding NASA CV-990 airborne laboratory data obtained over wide areas in the Arctic Basin during the Main Arctic Ice Dynamics Joint Experiment (1975) to illustrate the applicability of passive-microwave remote sensing for monitoring the time dependence of sea-ice concentration (divergence). These observations indicate significant variations in the sea-ice concentration in the spring, late fall and early winter. In addition, deep in the interior of the Arctic polar sea-ice pack, heretofore unobserved large areas, several hundred kilometers in extent, of sea-ice concentrations as low as 50% are indicated. ?? 1978 D. Reidel Publishing Company.

76 FR 43616 - Procedures for Implementing the National Environmental Policy Act

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-21

... Studies. 4. NASA HQ 09/23/2009 ARRA Implementation of Venture-Class Mission, HQ ID-1095. 5. LaRC, VA 11/20.../2009 Develop Air Traffic Management Concepts. 5. NASA HQ 12/23/2009 ARRA-Funded Activities (HQ ID-1119... Composition, Cloud, Climate Coupling (TC-4). 3. WFF, VA 03/28/2008 ARCTAS Mission. The third proposed CatEx...

Arctic and Arctic-like rabies viruses: distribution, phylogeny and evolutionary history

PubMed Central

KUZMIN, I. V.; HUGHES, G. J.; BOTVINKIN, A. D.; GRIBENCHA, S. G.; RUPPRECHT, C. E.

2008-01-01

SUMMARY Forty-one newly sequenced isolates of Arctic and Arctic-like rabies viruses, were genetically compared to each other and to those available from GenBank. Four phylogenetic lineages of Arctic viruses were identified. Arctic-1 viruses circulate in Ontario, Arctic-2 viruses circulate in Siberia and Alaska, Arctic-3 viruses circulate circumpolarly, and a newly described lineage Arctic-4 circulates locally in Alaska. The oldest available isolates from Siberia (between 1950 and 1960) belong to the Arctic-2 and Arctic-3 lineages and share 98·6–99·2% N gene identity with contemporary viruses. Two lineages of Arctic-like viruses were identified in southern Asia and the Middle East (Arctic-like-1) and eastern Asia (Arctic-like-2). A time-scaled tree demonstrates that the time of the most recent common ancestor (TMRCA) of Arctic and Arctic-like viruses is dated between 1255 and 1786. Evolution of the Arctic viruses has occurred through a northerly spread. The Arctic-like-2 lineage diverged first, whereas Arctic viruses share a TMRCA with Arctic-like-1 viruses. PMID:17599781

Arctic and Arctic-like rabies viruses: distribution, phylogeny and evolutionary history.

PubMed

Kuzmin, I V; Hughes, G J; Botvinkin, A D; Gribencha, S G; Rupprecht, C E

2008-04-01

Forty-one newly sequenced isolates of Arctic and Arctic-like rabies viruses, were genetically compared to each other and to those available from GenBank. Four phylogenetic lineages of Arctic viruses were identified. Arctic-1 viruses circulate in Ontario, Arctic-2 viruses circulate in Siberia and Alaska, Arctic-3 viruses circulate circumpolarly, and a newly described lineage Arctic-4 circulates locally in Alaska. The oldest available isolates from Siberia (between 1950 and 1960) belong to the Arctic-2 and Arctic-3 lineages and share 98.6-99.2% N gene identity with contemporary viruses. Two lineages of Arctic-like viruses were identified in southern Asia and the Middle East (Arctic-like-1) and eastern Asia (Arctic-like-2). A time-scaled tree demonstrates that the time of the most recent common ancestor (TMRCA) of Arctic and Arctic-like viruses is dated between 1255 and 1786. Evolution of the Arctic viruses has occurred through a northerly spread. The Arctic-like-2 lineage diverged first, whereas Arctic viruses share a TMRCA with Arctic-like-1 viruses.

Aura Microwave Limb Sounder Estimates of Ozone Loss, 2004/2005 Arctic Winter

NASA Image and Video Library

2005-06-02

These data maps from the Microwave Limb Sounder on NASA Aura spacecraft depict levels of hydrogen chloride, chlorine monoxide, and ozone at an altitude of approximately 19 km 490,000 ft on selected days during the 2004-05 Arctic winter.

Arctic Warming as News - Perils and Possibilities

NASA Astrophysics Data System (ADS)

Revkin, A. C.

2015-12-01

A science journalist in his 30th year covering human-driven climate change, including on three Arctic reporting trips, reflects on successes and setbacks as news media, environmentalists and Arctic communities have tried to convey the significance of polar change to a public for which the ends of the Earth will always largely be a place of the imagination.Novel challenges are arising in the 24/7 online media environment, as when a paper by a veteran climate scientist proposing a mechanism for abrupt sea-level rise became a big news story before it was accepted by the open-review journal to which it had been submitted. New science is digging in on possible connections between changing Arctic sea ice and snow conditions and disruptive winter weather in more temperate northern latitudes, offering a potential link between this distant region and the lives of ordinary citizens. As cutting-edge research, such work gets substantial media attention. But, as with all new areas of inquiry, uncertainty dominates - creating the potential for distracting the public and policymakers from the many aspects of anthropogenic climate change that are firmly established - but, in a way, boring because of that.With the challenges, there are unprecedented opportunities for conveying Arctic science. In some cases, researchers on expeditions are partnering with media, offering both scientists and news outlets fresh ways to convey the story of Arctic change in an era of resource constraints.Innovative uses of crittercams, webcams, and satellite observations offer educators and interested citizens a way to track and appreciate Arctic change. But more can be done to engage the public directly without the news media as an intermediary, particularly if polar scientists or their institutions test some of the established practices honed by more experienced communicators at NASA.

Does a Relationship Between Arctic Low Clouds and Sea Ice Matter?

NASA Technical Reports Server (NTRS)

Taylor, Patrick C.

2016-01-01

Arctic low clouds strongly affect the Arctic surface energy budget. Through this impact Arctic low clouds influence important aspects of the Arctic climate system, namely surface and atmospheric temperature, sea ice extent and thickness, and atmospheric circulation. Arctic clouds are in turn influenced by these elements of the Arctic climate system, and these interactions create the potential for Arctic cloud-climate feedbacks. To further our understanding of potential Arctic cloudclimate feedbacks, the goal of this paper is to quantify the influence of atmospheric state on the surface cloud radiative effect (CRE) and its covariation with sea ice concentration (SIC). We build on previous research using instantaneous, active remote sensing satellite footprint data from the NASA A-Train. First, the results indicate significant differences in the surface CRE when stratified by atmospheric state. Second, there is a weak covariation between CRE and SIC for most atmospheric conditions. Third, the results show statistically significant differences in the average surface CRE under different SIC values in fall indicating a 3-5 W m(exp -2) larger LW CRE in 0% versus 100% SIC footprints. Because systematic changes on the order of 1 W m(exp -2) are sufficient to explain the observed long-term reductions in sea ice extent, our results indicate a potentially significant amplifying sea ice-cloud feedback, under certain meteorological conditions, that could delay the fall freeze-up and influence the variability in sea ice extent and volume. Lastly, a small change in the frequency of occurrence of atmosphere states may yield a larger Arctic cloud feedback than any cloud response to sea ice.

Preliminary design for Arctic atmospheric radiative transfer experiments

NASA Technical Reports Server (NTRS)

Zak, B. D.; Church, H. W.; Stamnes, K.; Shaw, G.; Filyushkin, V.; Jin, Z.; Ellingson, R. G.; Tsay, S. C.

1995-01-01

If current plans are realized, within the next few years, an extraordinary set of coordinated research efforts focusing on energy flows in the Arctic will be implemented. All are motivated by the prospect of global climate change. SHEBA (Surface Energy Budget of the Arctic Ocean), led by the National Science Foundation (NSF) and the Office of Naval Research (ONR), involves instrumenting an ice camp in the perennial Arctic ice pack, and taking data for 12-18 months. The ARM (Atmospheric Radiation Measurement) North Slope of Alaska and Adjacent Arctic Ocean (NSA/AAO) Cloud and Radiation Testbed (CART) focuses on atmospheric radiative transport, especially in the presence of clouds. The NSA/AAO CART involves instrumenting a sizeable area on the North Slope of Alaska and adjacent waters in the vicinity of Barrow, and acquiring data over a period of about 10 years. FIRE (First ISCCP (International Satellite Cloud Climatology Program) Regional Experiment) Phase 3 is a program led by the National Aeronautics and Space Administration (NASA) which focuses on Arctic clouds, and which is coordinated with SHEBA and ARM. FIRE has historically emphasized data from airborne and satellite platforms. All three program anticipate initiating Arctic data acquisition during spring, 1997. In light of his historic opportunity, the authors discuss a strawman atmospheric radiative transfer experimental plan that identifies which features of the radiative transport models they think should be tested, what experimental data are required for each type of test, the platforms and instrumentation necessary to acquire those data, and in general terms, how the experiments could be conducted. Aspects of the plan are applicable to all three programs.

The Arctic Grand Challenge: Abrupt Climate Change

NASA Astrophysics Data System (ADS)

Wilkniss, P. E.

2003-12-01

products as greenhouse gases to their regions of origin. Thus multinational company operations are affected by their own activities. There is a strong, convincing case, that these industrial giants must be involved in Arctic partnerships of the grand challenge. A most instructive, very successful example is the collaboration by the chemical companies after the discovery of the polar ozone holes, followed by the replacement of the culprit chlorofluorocarbon compounds. Public relations and involvement/education: The IPY offers a unique opportunity to showcase and drive home, into homes, the seriousness of the issue, Hollywood/Madison Avenue/ NASA style, nothing else will do. Ultimately we need to be mindful that "civilizations are ephemeral compared to species. -What we need is a primer on science, clearly written and unambiguous in its meaning-a primer for anyone interested in the state of the Earth and how to survive and live well on it." (James Lovelock, Science, 08/05/98). - Let's start in the Arctic-NOW.

The 1988 Arctic Survey, Diurnal Study (Sunrise and Sunset) and Peak Altitude (22 km) Flights for the In Situ Detection of ClO and BrO from the NASA ER-2 Aircraft

NASA Technical Reports Server (NTRS)

Anderson, James G.

1996-01-01

Two critical areas of research were addressed successfully by this research. The first involves NASA ER-2 airborne observations of ClO and BrO radical destruction of ozone within the arctic vortex. The second involves the analysis of diurnal variations in ClO, to test the production and loss rates of ClO that constitutes the test for coupling reactions between the chlorine and nitrogen systems. We discuss results from this research in order.

Understanding Arctic surface temperature differences in reanalyses

NASA Astrophysics Data System (ADS)

Cullather, R. I.; Zhao, B.; Shuman, C. A.; Nowicki, S.

2017-12-01

Reanalyses in the Arctic are widely used for model evaluation and for understanding contemporary climate change. Nevertheless, differences among reanalyses in fundamental meteorological variables including surface air temperature are large. For example, the 1980-2009 mean surface air temperature for the north polar cap (70°N-90°N) among global reanalyses span a range of 2.4 K, which approximates the average warming trend from these reanalyses over the 30-year period of 2.1 K. Understanding these differences requires evaluation over the three principal surface domains of the Arctic: glaciated land, the unglaciated terrestrial surface, and sea ice/ocean. An examination is conducted of contemporary global reanalyses of the ECMWF Interim project, NASA MERRA, MERRA-2, JRA-55, and NOAA CFSR using available in situ data and assessments of the surface energy budget. Overly-simplistic representations of the Greenland Ice Sheet surface are found to be associated with local warm air temperature biases in winter. A review of progress made in the development of the MERRA-2 land-ice representation is presented. Large uncertainty is also found in temperatures over the Arctic tundra and boreal forest zone. But a key focus of temperature differences for northern high latitudes is the Arctic Ocean. Near-surface air temperature differences over the Arctic Ocean are found to be related to discrepancies in sea ice and sea surface temperature boundary data, which are severely compromised in current reanalyses. Issues with the modeled representation of sea ice cover are an additional factor in reanalysis temperature trends. Differences in the representation of the surface energy budget among the various reanalyses are also reviewed.

Understanding Arctic Surface Temperature Differences in Reanalyses

NASA Technical Reports Server (NTRS)

Cullather, Richard; Zhao, Bin; Shuman, Christopher; Nowicki, Sophie

2017-01-01

Reanalyses in the Arctic are widely used for model evaluation and for understanding contemporary climate change. Nevertheless, differences among reanalyses in fundamental meteorological variables including surface air temperature are large. For example, the 1980-2009 mean surface air temperature for the north polar cap (70ÂdegN-90ÂdegN) among global reanalyses span a range of 2.4 K, which approximates the average warming trend from these reanalyses over the 30-year period of 2.1 K. Understanding these differences requires evaluation over the three principal surface domains of the Arctic: glaciated land, the unglaciated terrestrial surface, and sea ice/ocean. An examination is conducted of contemporary global reanalyses of the ECMWF Interim project, NASA MERRA, MERRA-2, JRA-55, and NOAA CFSR using available in situ data and assessments of the surface energy budget. Overly-simplistic representations of the Greenland Ice Sheet surface are found to be associated with local warm air temperature biases in winter. A review of progress made in the development of the MERRA-2 land-ice representation is presented. Large uncertainty is also found in temperatures over the Arctic tundra and boreal forest zone. But a key focus of temperature differences for northern high latitudes is the Arctic Ocean. Near-surface air temperature differences over the Arctic Ocean are found to be related to discrepancies in sea ice and sea surface temperature boundary data, which are severely compromised in current reanalyses. Issues with the modeled representation of sea ice cover are an additional factor in reanalysis temperature trends. Differences in the representation of the surface energy budget among the various reanalyses are also reviewed.

Interfacing with in-Situ Data Networks during the Arctic Boreal Vulnerability Experiment (ABoVE)

NASA Astrophysics Data System (ADS)

McInerney, M.; Griffith, P. C.; Duffy, D.; Hoy, E.; Schnase, J. L.; Sinno, S.; Thompson, J. H.

2014-12-01

The Arctic Boreal Vulnerability Experiment (ABoVE) is designed to improve understanding of the causes and impacts of ecological changes in Arctic/boreal regions, and will integrate field-based studies, modeling, and data from airborne and satellite remote sensing. ABoVE will result in a fuller understanding of ecosystem vulnerability and resilience to environmental change in the Arctic and boreal regions of western North America, and provide scientific information required to develop options for societal responses to the impacts of these changes. The studies sponsored by NASA during ABoVE will be coordinated with research and in-situ monitoring activities being sponsored by a number of national and international partners. The NASA Center for Climate Simulation at the Goddard Space Flight Center has partnered with the NASA Carbon Cycle & Ecosystems Office to create a science cloud designed for this field campaign - the ABoVE Science Cloud (ASC). The ASC combines high performance computing with emerging technologies to create an environment specifically designed for large-scale modeling, analysis of remote sensing data, copious disk storage with integrated data management, and integration of core variables from in-situ networks identified by the ABoVE Science Definition Team. In this talk, we will present the scientific requirements driving the development of the ABoVE Science Cloud, discuss the necessary interfaces, both computational and human, with in-situ monitoring networks, and show examples of how the ASC is being used to meet the needs of the ABoVE campaign.

Factors Controlling the Properties of Multi-Phase Arctic Stratocumulus Clouds

NASA Technical Reports Server (NTRS)

Fridlind, Ann; Ackerman, Andrew; Menon, Surabi

2005-01-01

The 2004 Multi-Phase Arctic Cloud Experiment (M-PACE) IOP at the ARM NSA site focused on measuring the properties of autumn transition-season arctic stratus and the environmental conditions controlling them, including concentrations of heterogeneous ice nuclei. Our work aims to use a large-eddy simulation (LES) code with embedded size-resolved aerosol and cloud microphysics to identify factors controlling multi-phase arctic stratus. Our preliminary simulations of autumn transition-season clouds observed during the 1994 Beaufort and Arctic Seas Experiment (BASE) indicated that low concentrations of ice nuclei, which were not measured, may have significantly lowered liquid water content and thereby stabilized cloud evolution. However, cloud drop concentrations appeared to be virtually immune to changes in liquid water content, indicating an active Bergeron process with little effect of collection on drop number concentration. We will compare these results with preliminary simulations from October 8-13 during MPACE. The sensitivity of cloud properties to uncertainty in other factors, such as large-scale forcings and aerosol profiles, will also be investigated. Based on the LES simulations with M-PACE data, preliminary results from the NASA GlSS single-column model (SCM) will be used to examine the sensitivity of predicted cloud properties to changing cloud drop number concentrations for multi-phase arctic clouds. Present parametrizations assumed fixed cloud droplet number concentrations and these will be modified using M-PACE data.

Monitoring Arctic Sea ice using ERTS imagery. [Bering Sea, Beaufort Sea, Canadian Archipelago, and Greenland Sea

NASA Technical Reports Server (NTRS)

Barnes, J. C.; Bowley, C. J.

1974-01-01

Because of the effect of sea ice on the heat balance of the Arctic and because of the expanding economic interest in arctic oil and other minerals, extensive monitoring and further study of sea ice is required. The application of ERTS data for mapping ice is evaluated for several arctic areas, including the Bering Sea, the eastern Beaufort Sea, parts of the Canadian Archipelago, and the Greenland Sea. Interpretive techniques are discussed, and the scales and types of ice features that can be detected are described. For the Bering Sea, a sample of ERTS imagery is compared with visual ice reports and aerial photography from the NASA CV-990 aircraft.

Arctic Sea Ice Is Losing Its Bulwark Against Warming Summers

NASA Image and Video Library

2017-12-08

Arctic sea ice, the vast sheath of frozen seawater floating on the Arctic Ocean and its neighboring seas, has been hit with a double whammy over the past decades: as its extent shrunk, the oldest and thickest ice has either thinned or melted away, leaving the sea ice cap more vulnerable to the warming ocean and atmosphere. “What we’ve seen over the years is that the older ice is disappearing,” said Walt Meier, a sea ice researcher at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “This older, thicker ice is like the bulwark of sea ice: a warm summer will melt all the young, thin ice away but it can’t completely get rid of the older ice. But this older ice is becoming weaker because there’s less of it and the remaining old ice is more broken up and thinner, so that bulwark is not as good as it used to be.” Read more: go.nasa.gov/2dPJ9zT NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

The Arctic Observing Viewer (AOV): Visualization, Data Discovery, Strategic Assessment, and Decision Support for Arctic Observing

NASA Astrophysics Data System (ADS)

Cody, R. P.; Manley, W. F.; Gaylord, A. G.; Kassin, A.; Villarreal, S.; Barba, M.; Dover, M.; Escarzaga, S. M.; Habermann, T.; Kozimor, J.; Score, R.; Tweedie, C. E.

2016-12-01

To better assess progress in Arctic Observing made by U.S. SEARCH, NSF AON, SAON, and related initiatives, an updated version of the Arctic Observing Viewer (AOV; http://ArcticObservingViewer.org) has been released. This web mapping application and information system conveys the who, what, where, and when of "data collection sites" - the precise locations of monitoring assets, observing platforms, and wherever repeat marine or terrestrial measurements have been taken. Over 8000 sites across the circum-arctic are documented including a range of boreholes, ship tracks, buoys, towers, sampling stations, sensor networks, vegetation plots, stream gauges, ice cores, observatories, and more. Contributing partners are the U.S. NSF, ACADIS, ADIwg, AOOS, a2dc, AON, CAFF, GINA, IASOA, INTERACT, NASA ABoVE, and USGS, among others. Users can visualize, navigate, select, search, draw, print, view details, and follow links to obtain a comprehensive perspective of environmental monitoring efforts. We continue to develop, populate, and enhance AOV. Recent improvements include: a more intuitive and functional search tool, a modern cross-platform interface using javascript and HTML5, and hierarchical ISO metadata coupled with RESTful web services & metadata XLinks to span the data life cycle (from project planning to establishment of data collection sites to release of scientific datasets). Additionally, through collaborations with the Barrow Area Information Database (BAID, www.barrowmapped.org) we are exploring linkages with datacenters and have developed a prototype dashboard application that allows users to explore data services in the AOV application. AOV is founded on principles of interoperability, such that agencies and organizations can use the AOV Viewer and web services for their own purposes. In this way, AOV complements other distributed yet interoperable cyber resources and helps science planners, funding agencies, investigators, data specialists, and others to: assess

Documenting PyroCb Development on High-Intensity Boreal Fires: Implications for the Arctic Atmosphere

NASA Astrophysics Data System (ADS)

Stocks, B. J.; Fromm, M. D.; Servranckx, R.; Lindsey, D.

2007-12-01

The recent confirmation that smoke from high-intensity boreal forest fires can reach the Upper Troposphere/Lower Stratosphere (UTLS) through pyroconvection and be transported long distances has raised concern over the wider-scale environmental impact of boreal fire smoke. This concern is further elevated as climate change projections indicate a significant increase in the frequency and severity of boreal forest fires over the next century. Smoke in the UTLS is frequently transported to the Arctic and may have important implications for the radiative energy budget in the polar region. Soot deposition from fires may lead to enhanced melting of sea ice and glaciers, and the chemical impact of fire emissions at high altitudes is largely unknown. This knowledge gap will be addressed during the International Polar Year (IPY), as boreal fire emissions will be tracked and documented in detail through aerial, satellite and ground-based measurements, as a key component of the POLARCAT (Polar Study using Aircraft, Remote Sensing, Surface Measurements and Models, of Climate, Chemistry, Aerosols, and Transport) and ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) projects to be conducted in 2008. A large fire in the Canadian Northwest Territories burned throughout the month of June 2007, in a remote region where forest fires are not actively suppressed, eventually reaching 90,000 hectares in size. This fire was monitored for blowup one week in advance; it erupted into pyroconvection on June 25, 2007. We present an analysis of this event combining satellite data with ground-based measurements to document the development and impact of this classic pyroCb event. Under extreme fire danger conditions, the fire burned close to 20,000 hectares on that day. Fire behavior was consistent with predictions using the Canadian Fire Behavior Prediction System, with the fire spreading at 2.7 km/hr, consuming 33,000 kg of fuel hourly, generating an

Review of science issues, deployment strategy, and status for the ARM north slope of Alaska-Adjacent Arctic Ocean climate research site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stamnes, K.; Ellingson, R.G.; Curry, J.A.

1999-01-01

Recent climate modeling results point to the Arctic as a region that is particularly sensitive to global climate change. The Arctic warming predicted by the models to result from the expected doubling of atmospheric carbon dioxide is two to three times the predicted mean global warming, and considerably greater than the warming predicted for the Antarctic. The North Slope of Alaska-Adjacent Arctic Ocean (NSA-AAO) Cloud and Radiation Testbed (CART) site of the Atmospheric Radiation Measurement (ARM) Program is designed to collect data on temperature-ice-albedo and water vapor-cloud-radiation feedbacks, which are believed to be important to the predicted enhanced warming inmore » the Arctic. The most important scientific issues of Arctic, as well as global, significance to be addressed at the NSA-AAO CART site are discussed, and a brief overview of the current approach toward, and status of, site development is provided. ARM radiometric and remote sensing instrumentation is already deployed and taking data in the perennial Arctic ice pack as part of the SHEBA (Surface Heat Budget of the Arctic ocean) experiment. In parallel with ARM`s participation in SHEBA, the NSA-AAO facility near Barrow was formally dedicated on 1 July 1997 and began routine data collection early in 1998. This schedule permits the US Department of Energy`s ARM Program, NASA`s Arctic Cloud program, and the SHEBA program (funded primarily by the National Science Foundation and the Office of Naval Research) to be mutually supportive. In addition, location of the NSA-AAO Barrow facility on National Oceanic and Atmospheric Administration land immediately adjacent to its Climate Monitoring and Diagnostic Laboratory Barrow Observatory includes NOAA in this major interagency Arctic collaboration.« less

NASA’s Aerial Survey of Polar Ice Expands Its Arctic Reach

NASA Image and Video Library

2017-12-08

For the past eight years, Operation IceBridge, a NASA mission that conducts aerial surveys of polar ice, has produced unprecedented three-dimensional views of Arctic and Antarctic ice sheets, providing scientists with valuable data on how polar ice is changing in a warming world. Now, for the first time, the campaign will expand its reach to explore the Arctic’s Eurasian Basin through two research flights based out of Svalbard, a Norwegian archipelago in the northern Atlantic Ocean. More: go.nasa.gov/2ngAxX2 Credits: NASA/Nathan Kurtz NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

The Distribution of Snow Black Carbon observed in the Arctic and Compared to the GISS-PUCCINI Model

NASA Technical Reports Server (NTRS)

Dou, T.; Xiao, C.; Shindell, D. T.; Liu, J.; Eleftheriadis, K.; Ming, J.; Qin, D.

2012-01-01

In this study, we evaluate the ability of the latest NASA GISS composition-climate model, GISS-E2- PUCCINI, to simulate the spatial distribution of snow BC (sBC) in the Arctic relative to present-day observations. Radiative forcing due to BC deposition onto Arctic snow and sea ice is also estimated. Two sets of model simulations are analyzed, where meteorology is linearly relaxed towards National Centers for Environmental Prediction (NCEP) and towards NASA Modern Era Reanalysis for Research and Applications (MERRA) reanalyses. Results indicate that the modeled concentrations of sBC are comparable with presentday observations in and around the Arctic Ocean, except for apparent underestimation at a few sites in the Russian Arctic. That said, the model has some biases in its simulated spatial distribution of BC deposition to the Arctic. The simulations from the two model runs are roughly equal, indicating that discrepancies between model and observations come from other sources. Underestimation of biomass burning emissions in Northern Eurasia may be the main cause of the low biases in the Russian Arctic. Comparisons of modeled aerosol BC (aBC) with long-term surface observations at Barrow, Alert, Zeppelin and Nord stations show significant underestimation in winter and spring concentrations in the Arctic (most significant in Alaska), although the simulated seasonality of aBC has been greatly improved relative to earlier model versions. This is consistent with simulated biases in vertical profiles of aBC, with underestimation in the lower and middle troposphere but overestimation in the upper troposphere and lower stratosphere, suggesting that the wet removal processes in the current model may be too weak or that vertical transport is too rapid, although the simulated BC lifetime seems reasonable. The combination of observations and modeling provides a comprehensive distribution of sBC over the Arctic. On the basis of this distribution, we estimate the decrease in snow

Techniques for Estimating Emissions Factors from Forest Burning: ARCTAS and SEAC4RS Airborne Measurements Indicate which Fires Produce Ozone

NASA Technical Reports Server (NTRS)

Chatfield, Robert B.; Andreae, Meinrat O.

2016-01-01

Previous studies of emission factors from biomass burning are prone to large errors since they ignore the interplay of mixing and varying pre-fire background CO2 levels. Such complications severely affected our studies of 446 forest fire plume samples measured in the Western US by the science teams of NASA's SEAC4RS and ARCTAS airborne missions. Consequently we propose a Mixed Effects Regression Emission Technique (MERET) to check techniques like the Normalized Emission Ratio Method (NERM), where use of sequential observations cannot disentangle emissions and mixing. We also evaluate a simpler "consensus" technique. All techniques relate emissions to fuel burned using C(burn) = delta C(tot) added to the fire plume, where C(tot) approximately equals (CO2 = CO). Mixed-effects regression can estimate pre-fire background values of C(tot) (indexed by observation j) simultaneously with emissions factors indexed by individual species i, delta, epsilon lambda tau alpha-x(sub I)/C(sub burn))I,j. MERET and "consensus" require more than emissions indicators. Our studies excluded samples where exogenous CO or CH4 might have been fed into a fire plume, mimicking emission. We sought to let the data on 13 gases and particulate properties suggest clusters of variables and plume types, using non-negative matrix factorization (NMF). While samples were mixtures, the NMF unmixing suggested purer burn types. Particulate properties (b scant, b abs, SSA, AAE) and gas-phase emissions were interrelated. Finally, we sought a simple categorization useful for modeling ozone production in plumes. Two kinds of fires produced high ozone: those with large fuel nitrogen as evidenced by remnant CH3CN in the plumes, and also those from very intense large burns. Fire types with optimal ratios of delta-NOy/delta- HCHO associate with the highest additional ozone per unit Cburn, Perhaps these plumes exhibit limited NOx binding to reactive organics. Perhaps these plumes exhibit limited NOx binding to

Techniques for Estimating Emissions Factors from Forest Burning: ARCTAS and SEAC4RS Airborne Measurements Indicate Which Fires Produce Ozone

NASA Technical Reports Server (NTRS)

Chatfield, Robert B.; Andreae, Meinrat O.

2015-01-01

Previous studies of emission factors from biomass burning are prone to large errors since they ignore the interplay of mixing and varying pre-fire background CO2 levels. Such complications severely affected our studies of 446 forest fire plume samples measured in the Western US by the science teams of NASA's SEAC4RS and ARCTAS airborne missions. Consequently we propose a Mixed Effects Regression Emission Technique (MERET) to check techniques like the Normalized Emission Ratio Method (NERM), where use of sequential observations cannot disentangle emissions and mixing. We also evaluate a simpler "consensus" technique. All techniques relate emissions to fuel burned using C(sub burn) = delta C(sub tot) added to the fire plume, where C(sub tot) approximately equals (CO2 + CO). Mixed-effects regression can estimate pre-fire background values of Ctot (indexed by observation j) simultaneously with emissions factors indexed by individual species i, delta epsilon lambda tau alpha-x(sub i)/(C(sub burn))i,j., MERET and "consensus" require more than two emissions indicators. Our studies excluded samples where exogenous CO or CH4 might have been fed into a fire plume, mimicking emission. We sought to let the data on 13 gases and particulate properties suggest clusters of variables and plume types, using non-negative matrix factorization (NMF). While samples were mixtures, the NMF unmixing suggested purer burn types. Particulate properties (bscat, babs, SSA, AAE) and gas-phase emissions were interrelated. Finally, we sought a simple categorization useful for modeling ozone production in plumes. Two kinds of fires produced high ozone: those with large fuel nitrogen as evidenced by remnant CH3CN in the plumes, and also those from very intense large burns. Fire types with optimal ratios of delta-NOy/delta- HCHO associate with the highest additional ozone per unit Cburn, Perhaps these plumes exhibit limited NOx binding to reactive organics. Perhaps these plumes exhibit limited NOx

2015 Arctic Sea Ice Maximum Annual Extent Is Lowest On Record

NASA Image and Video Library

2015-03-19

The sea ice cap of the Arctic appeared to reach its annual maximum winter extent on Feb. 25, according to data from the NASA-supported National Snow and Ice Data Center (NSIDC) at the University of Colorado, Boulder. At 5.61 million square miles (14.54 million square kilometers), this year’s maximum extent was the smallest on the satellite record and also one of the earliest. Read more: 1.usa.gov/1Eyvelz Credit: NASA's Goddard Space Flight Center NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

In situ observations of Arctic cloud properties across the Beaufort Sea marginal ice zone

NASA Astrophysics Data System (ADS)

Corr, C.; Moore, R.; Winstead, E.; Thornhill, K. L., II; Crosbie, E.; Ziemba, L. D.; Beyersdorf, A. J.; Chen, G.; Martin, R.; Shook, M.; Corbett, J.; Smith, W. L., Jr.; Anderson, B. E.

2016-12-01

Clouds play an important role in Arctic climate. This is particularly true over the Arctic Ocean where feedbacks between clouds and sea-ice impact the surface radiation budget through modifications of sea-ice extent, ice thickness, cloud base height, and cloud cover. This work summarizes measurements of Arctic cloud properties made aboard the NASA C-130 aircraft over the Beaufort Sea during ARISE (Arctic Radiation - IceBridge Sea&Ice Experiment) in September 2014. The influence of surface-type on cloud properties is also investigated. Specifically, liquid water content (LWC), droplet concentrations, and droplet size distributions are compared for clouds sampled over three distinct regimes in the Beaufort Sea: 1) open water, 2) the marginal ice zone, and 3) sea-ice. Regardless of surface type, nearly all clouds intercepted during ARISE were liquid-phase clouds. However, differences in droplet size distributions and concentrations were evident for the surface types; clouds over the MIZ and sea-ice generally had fewer and larger droplets compared to those over open water. The potential implication these results have for understanding cloud-surface albedo climate feedbacks in Arctic are discussed.

Polar Bears Across the Arctic Face Shorter Sea Ice Season

NASA Image and Video Library

2017-12-08

Polar bears already face shorter ice seasons - limiting prime hunting and breeding opportunities. Nineteen separate polar bear subpopulations live throughout the Arctic, spending their winters and springs roaming on sea ice and hunting. The bears have evolved mainly to eat seals, which provide necessary fats and nutrients in the harsh Arctic environment. Polar bears can't outswim their prey, so instead they perch on the ice as a platform and ambush seals at breathing holes or break through the ice to access their dens. The total number of ice-covered days declined at the rate of seven to 19 days per decade between 1979 and 2014. The decline was even greater in the Barents Sea and the Arctic basin. Sea ice concentration during the summer months — an important measure because summertime is when some subpopulations are forced to fast on land — also declined in all regions, by 1 percent to 9 percent per decade. Read more: go.nasa.gov/2cIZSSc Photo credit: Mario Hoppmann

Scenarios Creation and Use in the Arctic Council's Arctic Marine Shipping Assessment

NASA Astrophysics Data System (ADS)

Brigham, L. W.

2016-12-01

The Arctic Council's Arctic Marine Shipping Assessment (AMSA), conducted 2004-2009, used a scenarios-based approach to reveal the complexity of future Arctic marine navigation and to develop a set of plausible futures. The initial task was to use experts and stakeholders in brainstorming sessions to identify the key drivers and uncertainties for Arctic marine navigation. AMSA scenario participants identified 120 driving forces or factors that may influence future levels of marine activity. This effort illustrated the broad, global connections that can impact future use of the Arctic Ocean. Two primary factors were selected to anchor, as axes of uncertainty, the scenarios matrix: resources and trade (the level of demand for Arctic natural resources and trade); and, governance (the degree of relative stability of rules and standards for marine use both within the Arctic and internationally). Four scenarios were created by crossing the two primary drivers: a Polar Lows scenario (low demand and unstable governance); an Arctic Race scenario (high demand and unstable governance); a Polar Preserve scenario (low demand and stable governance); and, an Arctic Saga scenario (high demand and stable governance). The AMSA scenarios effort proved to be an effective and powerful way to communicate to the Arctic Council diplomats, Arctic indigenous peoples, maritime stakeholders and many other actors in the global community the complexities influencing the future of Arctic shipping and marine operations. The scenarios approach facilitated unconstrained thinking and identified the many plausible linkages of the Arctic to the global economic system. The AMSA scenarios work was influential in the Arctic ministers' approval of the framework set of AMSA recommendations that are being implemented today to enhance Arctic marine safety and environmental protection.

NASA Sea Ice and Snow Validation Program for the DMSP SSM/I: NASA DC-8 flight report

NASA Technical Reports Server (NTRS)

Cavalieri, D. J.

1988-01-01

In June 1987 a new microwave sensor called the Special Sensor Microwave Imager (SSM/I) was launched as part of the Defense Meteorological Satellite Program (DMSP). In recognition of the importance of this sensor to the polar research community, NASA developed a program to acquire the data, to convert the data into sea ice parameters, and finally to validate and archive both the SSM/I radiances and the derived sea ice parameters. Central to NASA's sea ice validation program was a series of SSM/I aircraft underflights with the NASA DC-8 airborne Laboratory. The mission (the Arctic '88 Sea Ice Mission) was completed in March 1988. This report summarizes the mission and includes a summary of aircraft instrumentation, coordination with participating Navy aircraft, flight objectives, flight plans, data collected, SSM/I orbits for each day during the mission, and lists several piggyback experiments supported during this mission.

The Arctic Research Consortium of the United States (ARCUS): Connecting Arctic Research

NASA Astrophysics Data System (ADS)

Rich, R. H.; Wiggins, H. V.; Creek, K. R.; Sheffield Guy, L.

2015-12-01

This presentation will highlight the recent activities of the Arctic Research Consortium of the United States (ARCUS) to connect Arctic research. ARCUS is a nonprofit membership organization of universities and institutions that have a substantial commitment to research in the Arctic. ARCUS was formed in 1988 to serve as a forum for planning, facilitating, coordinating, and implementing interdisciplinary studies of the Arctic; to act as a synthesizer and disseminator of scientific information on arctic research; and to educate scientists and the general public about the needs and opportunities for research in the Arctic. ARCUS, in collaboration with the broader science community, relevant agencies and organizations, and other stakeholders, coordinates science planning and educational activities across disciplinary and organizational boundaries. Examples of ARCUS projects include: Arctic Sea Ice Outlook - an international effort that provides monthly summer reports synthesizing community estimates of the expected sea ice minimum. Sea Ice for Walrus Outlook - a resource for Alaska Native subsistence hunters, coastal communities, and others that provides weekly reports with information on sea ice conditions relevant to walrus in Alaska waters. PolarTREC (Teachers and Researchers Exploring and Collaborating) - a program whereby K-12 educators and researchers work together in hands-on field experiences in the Arctic and Antarctic to advance polar science education. ArcticInfo mailing list, Witness the Arctic newsletter, and the Arctic Calendar - communication tools for the arctic science community to keep apprised of relevant news, meetings, and announcements. Coordination for the Study of Environmental Arctic Change (SEARCH) program, which aims to provide scientific understanding of arctic environmental change to help society understand and respond to a rapidly changing Arctic. More information about these and other ARCUS activities can be found at the ARCUS website at

The melting sea ice of Arctic polar cap in the summer solstice month and the role of ocean

NASA Astrophysics Data System (ADS)

Lee, S.; Yi, Y.

2014-12-01

The Arctic sea ice is becoming smaller and thinner than climatological standard normal and more fragmented in the early summer. We investigated the widely changing Arctic sea ice using the daily sea ice concentration data. Sea ice data is generated from brightness temperature data derived from the sensors: Defense Meteorological Satellite Program (DMSP)-F13 Special Sensor Microwave/Imagers (SSM/Is), the DMSP-F17 Special Sensor Microwave Imager/Sounder (SSMIS) and the Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E) instrument on the NASA Earth Observing System (EOS) Aqua satellite. We tried to figure out appearance of arctic sea ice melting region of polar cap from the data of passive microwave sensors. It is hard to explain polar sea ice melting only by atmosphere effects like surface air temperature or wind. Thus, our hypothesis explaining this phenomenon is that the heat from deep undersea in Arctic Ocean ridges and the hydrothermal vents might be contributing to the melting of Arctic sea ice.

Explore Arctic Health.

PubMed

Lebow, Mahria

2014-04-01

The Arctic Health web site is a portal to Arctic-specific, health related content. The site provides expertly organized and annotated resources pertinent to northern peoples and places, including health information, research publications and environmental information. This site also features the Arctic Health Publications Database, which indexes an array of Arctic-related resources.

Arctic circulation regimes

PubMed Central

Proshutinsky, Andrey; Dukhovskoy, Dmitry; Timmermans, Mary-Louise; Krishfield, Richard; Bamber, Jonathan L.

2015-01-01

Between 1948 and 1996, mean annual environmental parameters in the Arctic experienced a well-pronounced decadal variability with two basic circulation patterns: cyclonic and anticyclonic alternating at 5 to 7 year intervals. During cyclonic regimes, low sea-level atmospheric pressure (SLP) dominated over the Arctic Ocean driving sea ice and the upper ocean counterclockwise; the Arctic atmosphere was relatively warm and humid, and freshwater flux from the Arctic Ocean towards the subarctic seas was intensified. By contrast, during anticylonic circulation regimes, high SLP dominated driving sea ice and the upper ocean clockwise. Meanwhile, the atmosphere was cold and dry and the freshwater flux from the Arctic to the subarctic seas was reduced. Since 1997, however, the Arctic system has been under the influence of an anticyclonic circulation regime (17 years) with a set of environmental parameters that are atypical for this regime. We discuss a hypothesis explaining the causes and mechanisms regulating the intensity and duration of Arctic circulation regimes, and speculate how changes in freshwater fluxes from the Arctic Ocean and Greenland impact environmental conditions and interrupt their decadal variability. PMID:26347536

White Arctic vs. Blue Arctic: Making Choices

NASA Astrophysics Data System (ADS)

Pfirman, S. L.; Newton, R.; Schlosser, P.; Pomerance, R.; Tremblay, B.; Murray, M. S.; Gerrard, M.

2015-12-01

As the Arctic warms and shifts from icy white to watery blue and resource-rich, tension is arising between the desire to restore and sustain an ice-covered Arctic and stakeholder communities that hope to benefit from an open Arctic Ocean. If emissions of greenhouse gases to the atmosphere continue on their present trend, most of the summer sea ice cover is projected to be gone by mid-century, i.e., by the time that few if any interventions could be in place to restore it. There are many local as well as global reasons for ice restoration, including for example, preserving the Arctic's reflectivity, sustaining critical habitat, and maintaining cultural traditions. However, due to challenges in implementing interventions, it may take decades before summer sea ice would begin to return. This means that future generations would be faced with bringing sea ice back into regions where they have not experienced it before. While there is likely to be interest in taking action to restore ice for the local, regional, and global services it provides, there is also interest in the economic advancement that open access brings. Dealing with these emerging issues and new combinations of stakeholders needs new approaches - yet environmental change in the Arctic is proceeding quickly and will force the issues sooner rather than later. In this contribution we examine challenges, opportunities, and responsibilities related to exploring options for restoring Arctic sea ice and potential pathways for their implementation. Negotiating responses involves international strategic considerations including security and governance, meaning that along with local communities, state decision-makers, and commercial interests, national governments will have to play central roles. While these issues are currently playing out in the Arctic, similar tensions are also emerging in other regions.

AROME-Arctic: New operational NWP model for the Arctic region

NASA Astrophysics Data System (ADS)

Süld, Jakob; Dale, Knut S.; Myrland, Espen; Batrak, Yurii; Homleid, Mariken; Valkonen, Teresa; Seierstad, Ivar A.; Randriamampianina, Roger

2016-04-01

In the frame of the EU-funded project ACCESS (Arctic Climate Change, Economy and Society), MET Norway aimed 1) to describe the present monitoring and forecasting capabilities in the Arctic; and 2) to identify the key factors limiting the forecasting capabilities and to give recommendations on key areas to improve the forecasting capabilities in the Arctic. We have observed that the NWP forecast quality is lower in the Arctic than in the regions further south. Earlier research indicated that one of the factors behind this is the composition of the observing system in the Arctic, in particular the scarceness of conventional observations. To further assess possible strategies for alleviating the situation and propose scenarios for a future Arctic observing system, we have performed a set of experiments to gain a more detailed insight in the contribution of the components of the present observing system in a regional state-of-the-art non-hydrostatic NWP model using the AROME physics (Seity et al, 2011) at 2.5 km horizontal resolution - AROME-Arctic. Our observing system experiment studies showed that conventional observations (Synop, Buoys) can play an important role in correcting the surface state of the model, but prove that the present upper-air conventional (Radiosondes, Aircraft) observations in the area are too scarce to have a significant effect on forecasts. We demonstrate that satellite sounding data play an important role in improving forecast quality. This is the case with satellite temperature sounding data (AMSU-A, IASI), as well as with the satellite moisture sounding data (AMSU-B/MHS, IASI). With these sets of observations, the AROME-Arctic clearly performs better in forecasting extreme events, like for example polar lows. For more details see presentation by Randriamampianina et al. in this session. The encouraging performance of AROME-Arctic lead us to implement it with more observations and improved settings into daily runs with the objective to

Human adaptation responses to a rapidly changing Arctic: A research context for building system resilience

NASA Astrophysics Data System (ADS)

Chapin, T.; Brinkman, T. J.

2016-12-01

Although human behavior accounts for more uncertainty in future trajectories in climate change than do biophysical processes, most climate-change research fails to include human actions in research design and implementation. This is well-illustrated in the Arctic. At the global scale, arctic processes strongly influence the strength of biophysical feedbacks between global human emissions and the rate of climate warming. However, most human actions in the arctic have little effect on these feedbacks, so research can contribute most effectively to reduction in arctic warming through improved understanding of the strength of arctic-global biophysical feedbacks, as in NASA's ABoVE program, and its effective communication to policy makers and the public. In contrast, at the local to regional scale within the arctic, human actions may influence the ecological and societal consequences of arctic warming, so research benefits from active stakeholder engagement in research design and implementation. Human communities and other stakeholders (government and NGOs) respond heterogeneously to socioeconomic and environmental change, so research that documents the range of historical and current adaptive responses to change provides insights on the resilience (flexibility of future options) of social-ecological processes in the arctic. Alaskan communities have attempted a range of adaptive responses to coastal erosion (e.g., seasonal migration, protection in place, relocation), wildfire (fire suppression to use of fire to manage wildlife habitat or landscape heterogeneity), declining sea ice (e.g., new hunting technology, sea ice observations and predictions), and changes in wildlife and fish availability (e.g., switch to harvest of alternative species, harvest times, or harvest locations). Research that draws on both traditional and western knowledge facilitates adaptation and predictions of the likely societal consequences of climate change in the Arctic. Effective inclusion of

CARVE Measurements of Atmospheric Methane Concentrations and Emissions in Arctic and Boreal Alaska

NASA Astrophysics Data System (ADS)

Miller, C. E.; Miller, J. B.; Chang, R. Y.; Sweeney, C.; Karion, A.; Wofsy, S. C.; Henderson, J.; Eluszkiewicz, J.; Mountain, M.; Oechel, W. C.

2013-12-01

The Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) is a NASA Earth Ventures (EV-1) investigation designed to quantify correlations between atmospheric and surface state variables for the Alaskan terrestrial ecosystems through intensive seasonal aircraft campaigns, ground-based observations, and analysis sustained over a 5-year mission. CARVE bridges critical gaps in our knowledge and understanding of Arctic ecosystems, linkages between the Arctic hydrologic and terrestrial carbon cycles, and the feedbacks from fires and thawing permafrost. We present CARVE airborne measurements of spatial and temporal patterns in atmospheric CH4 concentrations and estimated surface-atmosphere emissions for Arctic and Boreal Alaska. Continuous in situ CH4, CO2 and CO data are supplemented by periodic whole air flask samples from which 13CH4 and non-methane hydrocarbons are used to assess the relative contributions of wetlands, fossil fuel combustion, and oil and gas production to the observed CH4 signals. The CARVE project has also initiated monthly 14CH4 sampling at Barrow, AK (BRW) and the CARVE Tower in Fox, AK (CRV) to evaluate seasonal changes in the fraction of old carbon being mobilized via methanogenesis.

Recovery and archiving key Arctic Alaska vegetation map and plot data for the Arctic-Boreal Vulnerability Field Experiment (ABoVE)

NASA Astrophysics Data System (ADS)

Walker, D. A.; Breen, A. L.; Broderson, D.; Epstein, H. E.; Fisher, W.; Grunblatt, J.; Heinrichs, T.; Raynolds, M. K.; Walker, M. D.; Wirth, L.

2013-12-01

Abundant ground-based information will be needed to inform remote-sensing and modeling studies of NASA's Arctic-Boreal Vulnerability Experiment (ABoVE). A large body of plot and map data collected by the Alaska Geobotany Center (AGC) and collaborators from the Arctic regions of Alaska and the circumpolar Arctic over the past several decades is being archived and made accessible to scientists and the public via the Geographic Information Network of Alaska's (GINA's) 'Catalog' display and portal system. We are building two main types of data archives: Vegetation Plot Archive: For the plot information we use a Turboveg database to construct the Alaska portion of the international Arctic Vegetation Archive (AVA) http://www.geobotany.uaf.edu/ava/. High quality plot data and non-digital legacy datasets in danger of being lost have highest priority for entry into the archive. A key aspect of the database is the PanArctic Species List (PASL-1), developed specifically for the AVA to provide a standard of species nomenclature for the entire Arctic biome. A wide variety of reports, documents, and ancillary data are linked to each plot's geographic location. Geoecological Map Archive: This database includes maps and remote sensing products and links to other relevant data associated with the maps, mainly those produced by the Alaska Geobotany Center. Map data include GIS shape files of vegetation, land-cover, soils, landforms and other categorical variables and digital raster data of elevation, multispectral satellite-derived data, and data products and metadata associated with these. The map archive will contain all the information that is currently in the hierarchical Toolik-Arctic Geobotanical Atlas (T-AGA) in Alaska http://www.arcticatlas.org, plus several additions that are in the process of development and will be combined with GINA's already substantial holdings of spatial data from northern Alaska. The Geoecological Atlas Portal uses GINA's Catalog tool to develop a

A Friend Acting Strangely: an Exhibition on Climate Change in the Arctic

NASA Astrophysics Data System (ADS)

Stauffer, B. W.; Fitzhugh, W. W.; Krupnik, I.; Mannes, J.; Rusk, K.

2003-12-01

The Arctic: A Friend Acting Strangely is a new exhibit being developed at the Smithsonian Institution's National Museum of Natural History (NMNH) as a part of the museum's Forces of Change exhibit series on global change issues. The exhibit will open to the public in Summer 2004 and is the third component of the series. The other two components are about El Niño (El Niño's Powerful Reach) and atmospheric chemistry (Change is in the Air). The Arctic exhibit's underlying theme is that current global change is causing such rapid shifts in Arctic weather and the polar environment that it has become `strange,' - or unpredictable - to its residents. The speed of change in Arctic ice and climate patterns, ocean and terrestrial ecosystems, and wildlife creates a great challenge for polar scientists; but it also advances beyond the experience and memory of northern indigenous people, who know it so well. The key issues the NMNH team faces in preparing the new exhibit are: how to document and display the forces and consequences of rapid change; how to make complex scientific processes and research comprehensible to visitors; and how to engage the general public in the on-going discussion. Because current shifts in the Arctic environment have been observed and recorded in much detail by scientists and Native residents alike, this topic offers unique opportunities beyond the museum presentation, including outreach through public programs and the Internet. The exhibit is being developed jointly by the NMNH Arctic Studies Center and Office of the Exhibits, and in close collaboration with NOAA' Office of Arctic Research, NSF' new Study of Environmental Arctic Change (SEARCH) initiative, and NASA's Earth Science Enterprise. Exhibit components will include objects, text, graphic panels, video, and a computer interactive. Special efforts will be made to present the voices and opinions of Arctic indigenous people who experience new challenges to their traditional subsistence

NASA's Arctic-Boreal Vulnerability Experiment: A large-scale study of environmental change in Western North America and its implications for ecological systems and society

NASA Astrophysics Data System (ADS)

Kasischke, E. S.; Hayes, D. J.; Griffith, P. C.; Larson, E. K.; Wickland, D. E.

2013-12-01

Climate change in high northern latitudes is unfolding faster than anywhere else on Earth, resulting in widespread changes in landscape structure and ecosystem function in the Arctic-Boreal Region (ABR). Recognizing its sensitivity, vulnerability and global importance, national- and international-level scientific efforts are now advancing our ability to observe, understand and model the complex, multi-scale processes that drive the ABR's natural and social systems. Long at the edge of our mental map of the world, environmental change in the ABR is increasingly becoming the focus of numerous policy discussions at the highest levels of decision-making. To improve our understanding of environmental change and its impacts in the ABR, the Terrestrial Ecology Program of the U.S. National Aeronautics and Space Administration (NASA) is planning its next major field campaign for Western Canada and Alaska. The field campaign will be based on the Arctic-Boreal Vulnerability Experiment (ABoVE) concept as described in the Revised Executive Summary from the ABoVE Scoping Study Report. The original Scoping Study Report provided the proof-of-concept demonstration of scientific importance and feasibility for this large-scale study. In early 2013, NASA announced the selection of the ABoVE Science Definition Team, which is charged with developing the Concise Experiment Plan for the campaign. Here, we outline the conceptual basis for ABoVE and present the compelling rationale explaining the scientific and societal importance of the study. We present the current status of the planning process, which includes development of the science questions to drive ABoVE research; the study design for the field campaign to address them; and the interagency and international collaborations necessary for implementation. The ABoVE study will focus on 1) developing a fuller understanding of ecosystem vulnerability to climate change in the ABR, and 2) providing the scientific information required to

Arctic rabies--a review.

PubMed

Mørk, Torill; Prestrud, Pål

2004-01-01

Rabies seems to persist throughout most arctic regions, and the northern parts of Norway, Sweden and Finland, is the only part of the Arctic where rabies has not been diagnosed in recent time. The arctic fox is the main host, and the same arctic virus variant seems to infect the arctic fox throughout the range of this species. The epidemiology of rabies seems to have certain common characteristics in arctic regions, but main questions such as the maintenance and spread of the disease remains largely unknown. The virus has spread and initiated new epidemics also in other species such as the red fox and the racoon dog. Large land areas and cold climate complicate the control of the disease, but experimental oral vaccination of arctic foxes has been successful. This article summarises the current knowledge and the typical characteristics of arctic rabies including its distribution and epidemiology.

Arctic Haze Analysis

NASA Astrophysics Data System (ADS)

Mei, Linlu; Xue, Yong

2013-04-01

The Arctic atmosphere is perturbed by nature/anthropogenic aerosol sources known as the Arctic haze, was firstly observed in 1956 by J. Murray Mitchell in Alaska (Mitchell, 1956). Pacyna and Shaw (1992) summarized that Arctic haze is a mixture of anthropogenic and natural pollutants from a variety of sources in different geographical areas at altitudes from 2 to 4 or 5 km while the source for layers of polluted air at altitudes below 2.5 km mainly comes from episodic transportation of anthropogenic sources situated closer to the Arctic. Arctic haze of low troposphere was found to be of a very strong seasonal variation characterized by a summer minimum and a winter maximum in Alaskan (Barrie, 1986; Shaw, 1995) and other Arctic region (Xie and Hopke, 1999). An anthropogenic factor dominated by together with metallic species like Pb, Zn, V, As, Sb, In, etc. and nature source such as sea salt factor consisting mainly of Cl, Na, and K (Xie and Hopke, 1999), dust containing Fe, Al and so on (Rahn et al.,1977). Black carbon and soot can also be included during summer time because of the mix of smoke from wildfires. The Arctic air mass is a unique meteorological feature of the troposphere characterized by sub-zero temperatures, little precipitation, stable stratification that prevents strong vertical mixing and low levels of solar radiations (Barrie, 1986), causing less pollutants was scavenged, the major revival pathway for particulates from the atmosphere in Arctic (Shaw, 1981, 1995; Heintzenberg and Larssen, 1983). Due to the special meteorological condition mentioned above, we can conclude that Eurasian is the main contributor of the Arctic pollutants and the strong transport into the Arctic from Eurasia during winter caused by the high pressure of the climatologically persistent Siberian high pressure region (Barrie, 1986). The paper intends to address the atmospheric characteristics of Arctic haze by comparing the clear day and haze day using different dataset

Program for Arctic Regional Climate Assessment (PARCA)

NASA Technical Reports Server (NTRS)

Gogineni, Sivaprasad; Thomas, Robert H.; Abdalati, Waleed (Editor)

1999-01-01

The Program for Arctic Regional Climate Assessment (PARCA) is a NASA-sponsored initiative with the prime objective of understanding the mass balance of the Greenland ice sheet. In October 1998, PARCA investigators met to review activities of the previous year, assess the program's progress, and plan future investigations directed at accomplishing that objective. Some exciting results were presented and discussed, including evidence of dramatic thinning of the ice sheet near the southeastern coast. Details of the investigations and many of the accomplishments are given in this report, but major highlights are given in the Executive Summary of the report.

Arctic potential - Could more structured view improve the understanding of Arctic business opportunities?

NASA Astrophysics Data System (ADS)

Hintsala, Henna; Niemelä, Sami; Tervonen, Pekka

2016-09-01

The increasing interest towards the Arctic has been witnessed during the past decades. However, the commonly shared definitions of the Arctic key concepts have not yet penetrated national and international arenas for political and economic decision making. The lack of jointly defined framework has made different analyses related to the Arctic quite limited considering the magnitude of economic potential embedded in Arctic. This paper is built on the key findings of two separate, yet connected projects carried out in the Oulu region, Finland. In this paper's approach, the Arctic context has been defined as a composition of three overlapping layers. The first layer is the phenomenological approach to define the Arctic region. The second layer is the strategy-level analysis to define different Arctic paths as well as a national level description of a roadmap to Arctic specialization. The third layer is the operationalization of the first two layers to define the Arctic business context and business opportunities. The studied case from Oulu region indicates that alternative futures for the Arctic competences and business activities are in resemblance with only two of the four identified strategic pathways. Introduction of other pathways to regional level actors as credible and attractive options would require additional, systematic efforts.

Squaring the Arctic Circle: connecting Arctic knowledge with societal needs

NASA Astrophysics Data System (ADS)

Wilkinson, J.

2017-12-01

Over the coming years the landscape of the Arctic will change substantially- environmentally, politically, and economically. Furthermore, Arctic change has the potential to significantly impact Arctic and non-Arctic countries alike. Thus, our science is in-demand by local communities, politicians, industry leaders and the public. During these times of transition it is essential that the links between science and society be strengthened further. Strong links between science and society is exactly what is needed for the development of better decision-making tools to support sustainable development, enable adaptation to climate change, provide the information necessary for improved management of assets and operations in the Arctic region, and and to inform scientific, economic, environmental and societal policies. By doing so tangible benefits will flow to Arctic societies, as well as for non-Arctic countries that will be significantly affected by climate change. Past experience has shown that the engagement with a broad range of stakeholders is not always an easy process. Consequently, we need to improve collaborative opportunities between scientists, indigenous/local communities, private sector, policy makers, NGOs, and other relevant stakeholders. The development of best practices in this area must build on the collective experiences of successful cross-sectorial programmes. Within this session we present some of the outreach work we have performed within the EU programme ICE-ARC, from community meetings in NW Greenland through to sessions at the United Nations Framework Convention on Climate Change COP Conferences, industry round tables, and an Arctic side event at the World Economic Forum in Davos.

Utilizing NASA Airborne Data to Investigate the Influence of Fuel Type on Biomass Burning Aerosol Properties

NASA Astrophysics Data System (ADS)

Odwuor, A.; Corr, C.; Griffin, R. J.; Pusede, S.; Anderson, B.; Beyersdorf, A. J.; Campuzano Jost, P.; Chen, G.; Day, D. A.; Diskin, G. S.; Jimenez, J. L.; Moore, R.; Nault, B.; Schwarz, J. P.; Shook, M.; Thornhill, K. L., II; Winstead, E.; Armin, W.; Ziemba, L. D.

2017-12-01

Climate models and satellite aerosol classification retrievals rely on well-characterized aerosol optical properties (e.g., scattering and absorption coefficients) that vary with aerosol type. However, generalized parameterizations of aerosol optical properties are weakened by actual variability in aerosol chemical and physical properties that arises from factors independent of aerosol source (e.g., meteorology). This is particularly true for biomass burning (BB) aerosol, which can vary in composition and size depending on burn conditions (e.g., smoldering versus flaming) and fuel. This work investigates the relationships between BB aerosol chemical, physical, and optical properties and fuel. We compare BB aerosol measured in fire plumes associated with distinct fuel types sampled during three NASA airborne research campaigns: boreal forest fires during the Arctic Research of the Troposphere from Aircraft and Satellites (ARCTAS) mission in Saskatchewan, Canada in July 2008; agricultural fires during the Studies of Emissions and Atmospheric Composition, Clouds, and Climate Coupling by Regional Surveys (SEAC4RS) over the continental U.S. in August/September 2013; and scrubland fires during the Student Airborne Research Program (SARP) mission in Southern California, U.S. in June 2016. Mean modified combustion efficiency values between 0.9 and 0.92 for the agricultural plumes and between 0.92 and 0.99 for the boreal and scrubland plumes indicate a significant flaming component to these fires. Despite similarities in burn conditions, SSA at 550nm was consistently lower for the agricultural and scrubland fires ( 0.92) compared to the boreal forest ( 0.96). While the ratio of black carbon to organic aerosol (OA) was similar among fires, differences in the OA were noted; f44/f60 ratios derived from Aerosol Mass Spectrometer OA measurements were consistently higher (>5) in scrubland and agricultural fires compared to boreal forest fires (<5). This suggests the amount of

Aura Microwave Limb Sounder Animation Illustrating the Interaction Between Temperatures and Chemicals Involved in Ozone Destruction, 2004-2005 Arctic Winter

NASA Image and Video Library

2005-06-02

This still from an animation created from data from the Microwave Limb Sounder instrument on NASA Aura spacecraft depicts the complex interaction of chemicals involved in the destruction of ozone during the 2005 Arctic winter.

Beryllium 7 and lead 210 in the Western Hemisphere Arctic atmosphere - Observations from three recent aircraft-based sampling programs

NASA Technical Reports Server (NTRS)

Dibb, Jack E.; Talbot, Robert W.; Gregory, Gerald L.

1992-01-01

Concentrations of the natural radionuclides Be-7 and Pb-210 in the Western Hemisphere Arctic atmosphere were determined during the recent NOAA Arctic Gas and Aerosol Sampling Program (AGASP 3) and NASA Global Tropospheric Experiment/Arctic Boundary Layer Expeditions (GTE/ABLE 3A and ABLE 3B) missions. Be-7 concentrations measured during the AGASP 3 mission north and west of Norway are in accord with previous results for high northern latitudes, but suggest that the 'stratospheric' air masses sampled at the highest elevations reached were significantly diluted with tropospheric air. Higher resolution sampling in the free troposphere of the North American Arctic during ABLE 3B revealed a layer of elevated Be-7 concentrations near 5 km. The distribution of Pb-210 in the high-altitude troposphere of North America during the summer was quite similar to distributions of more frequently measured aerosol species.

Coordinating for Arctic Conservation: Implementing Integrated Arctic Biodiversity Monitoring, Data Management and Reporting

NASA Astrophysics Data System (ADS)

Gill, M.; Svoboda, M.

2012-12-01

Arctic ecosystems and the biodiversity they support are experiencing growing pressure from various stressors (e.g. development, climate change, contaminants, etc.) while established research and monitoring programs remain largely uncoordinated, lacking the ability to effectively monitor, understand and report on biodiversity trends at the circumpolar scale. The maintenance of healthy arctic ecosystems is a global imperative as the Arctic plays a critical role in the Earth's physical, chemical and biological balance. A coordinated and comprehensive effort for monitoring arctic ecosystems is needed to facilitate effective and timely conservation and adaptation actions. The Arctic's size and complexity represents a significant challenge towards detecting and attributing important biodiversity trends. This demands a scaled, pan-arctic, ecosystem-based approach that not only identifies trends in biodiversity, but also identifies underlying causes. It is critical that this information be made available to generate effective strategies for adapting to changes now taking place in the Arctic—a process that ultimately depends on rigorous, integrated, and efficient monitoring programs that have the power to detect change within a "management" time frame. To meet these challenges and in response to the Arctic Climate Impact Assessment's recommendation to expand and enhance arctic biodiversity monitoring, the Conservation of Arctic Flora and Fauna (CAFF) Working Group of the Arctic Council launched the Circumpolar Biodiversity Monitoring Program (CBMP). The CBMP is led by Environment Canada on behalf of Canada and the Arctic Council. The CBMP is working with over 60 global partners to expand, integrate and enhance existing arctic biodiversity research and monitoring efforts to facilitate more rapid detection, communication and response to significant trends and pressures. Towards this end, the CBMP has established three Expert Monitoring Groups representing major Arctic

Ice-Free Arctic Ocean?

ERIC Educational Resources Information Center

Science Teacher, 2005

2005-01-01

The current warming trends in the Arctic may shove the Arctic system into a seasonally ice-free state not seen for more than one million years, according to a new report. The melting is accelerating, and researchers were unable to identify any natural processes that might slow the deicing of the Arctic. "What really makes the Arctic different…

Arctic climate tipping points.

PubMed

Lenton, Timothy M

2012-02-01

There is widespread concern that anthropogenic global warming will trigger Arctic climate tipping points. The Arctic has a long history of natural, abrupt climate changes, which together with current observations and model projections, can help us to identify which parts of the Arctic climate system might pass future tipping points. Here the climate tipping points are defined, noting that not all of them involve bifurcations leading to irreversible change. Past abrupt climate changes in the Arctic are briefly reviewed. Then, the current behaviour of a range of Arctic systems is summarised. Looking ahead, a range of potential tipping phenomena are described. This leads to a revised and expanded list of potential Arctic climate tipping elements, whose likelihood is assessed, in terms of how much warming will be required to tip them. Finally, the available responses are considered, especially the prospects for avoiding Arctic climate tipping points.

Arctic Refuge

Atmospheric Science Data Center

2014-05-15

article title:  Summer in the Arctic National Wildlife Refuge     View Larger Image This colorful image of the Arctic National Wildlife Refuge and the Beaufort Sea was acquired by the Multi-angle Imaging ...

The Arctic Visiting Speakers Program

NASA Astrophysics Data System (ADS)

Wiggins, H. V.; Fahnestock, J.

2013-12-01

The Arctic Visiting Speakers Program (AVS) is a program of the Arctic Research Consortium of the U.S. (ARCUS) and funded by the National Science Foundation. AVS provides small grants to researchers and other Arctic experts to travel and share their knowledge in communities where they might not otherwise connect. The program aims to: initiate and encourage arctic science education in communities with little exposure to arctic research; increase collaboration among the arctic research community; nurture communication between arctic researchers and community residents; and foster arctic science education at the local level. Individuals, community organizations, and academic organizations can apply to host a speaker. Speakers cover a wide range of arctic topics and can address a variety of audiences including K-12 students, graduate and undergraduate students, and the general public. Preference is given to tours that reach broad and varied audiences, especially those targeted to underserved populations. Between October 2000 and July 2013, AVS supported 114 tours spanning 9 different countries, including tours in 23 U.S. states. Tours over the past three and a half years have connected Arctic experts with over 6,600 audience members. Post-tour evaluations show that AVS consistently rates high for broadening interest and understanding of arctic issues. AVS provides a case study for how face-to-face interactions between arctic scientists and general audiences can produce high-impact results. Further information can be found at: http://www.arcus.org/arctic-visiting-speakers.

Arctic chemical Ozone Loss Observed by the AROTEL Instrument during the SOLVE Campaign, December 1999 - March 2000

NASA Technical Reports Server (NTRS)

McGee, Thomas J.; Burris, John F.; Hoegy, Walter; Newman, Paul; Heaps,William; Silbert, Donald; Lait, Leslie; Sumnicht, Grant; Twigg, Laurence

2000-01-01

During the winter of 1999-2000, the AROTEL instrument was deployed on the NASA DC-8 at Kiruna, Sweden for the SAGE III Ozone Loss Validation Experiment (SOLVE). Measurements of ozone, temperature and aerosols were made on 18 local science flights from December to March. Extremely low temperatures were observed throughout most of the Arctic vortex and polar stratospheric clouds were observed throughout the Arctic area during January. Significant ozone loss was measured after the sun began to rise on the vortex area in February. Ozone mixing ratios as low as 800 ppbv were observed during flights in March.

The Arctic Boreal Vulnerability Experiment: Observing, Understanding, and Predicting Social-Ecological Change in the Far North

NASA Astrophysics Data System (ADS)

Mack, M. C.; Goetz, S. J.; Kasischke, E. S.; Kimball, J. S.; Boelman, N.

2015-12-01

In the high northern latitudes, climate is warming more rapidly than anywhere else on Earth, transforming vulnerable arctic tundra and boreal forest landscapes. These changes are altering the structure and function of energy, water and carbon cycles, producing significant feedbacks to regional and global climate through changes in energy, water and carbon cycles. These changes are also challenging local and global society. At the local level, communities seek to adapt to new social-ecological regimes. At the global level, changing arctic and boreal systems are increasing becoming the focus of policy discussions at all levels of decision-making. National and international scientific efforts associated with a new NASA field campaign, the Arctic-Boreal Vulnerability Experiment (ABOVE) will advance our ability to observe, understand and predict the complex, multiscale and non-linear processes that are confronting the natural and social systems in this rapidly changing region. Over the next decade, the newly assembled ABOVE Science Team will pursue this overarching question: "How vulnerable or resilient are ecosystems and society to environmental change in the Arctic and boreal region of western North America?" Through integration of remote sensing and in situ observations with modeling of both ecological and social systems, the ABOVE Science Team will advance an interdisciplinary understanding of the Far North. In this presentation, we will discuss the conceptual basis for the ABOVE Field Campaign, describe Science Team composition and timeline, and update the community on activities. In addition, we will reflect on the visionary role of Dr. Diane Wickland, retired NASA Terrestrial Ecology Program Manager and lead of the Carbon Cycle & Ecosystems Focus Area, in the development and commencement of ABOVE.

A Regional, Integrated Monitoring System for the Hydrology of the Pan-Arctic Land Mass

NASA Technical Reports Server (NTRS)

Serreze, Mark; Barry, Roger; Nolin, Anne; Armstrong, Richard; Zhang, Ting-Jung; Vorosmarty, Charles; Lammers, Richard; Frolking, Steven; Bromwich, David; McDonald, Kyle

2005-01-01

Work under this NASA contract developed a system for monitoring and historical analysis of the major components of the pan-Arctic terrestrial water cycle. It is known as Arctic-RIMS (Regional Integrated Hydrological Monitoring System for the Pan-Arctic Landmass). The system uses products from EOS-era satellites, numerical weather prediction models, station records and other data sets in conjunction with an atmosphere-land surface water budgeting scheme. The intent was to compile operational (at 1-2 month time lags) gridded fields of precipitation (P), evapotranspiration (ET), P-ET, soil moisture, soil freeze/thaw state, active layer thickness, snow extent and its water equivalent, soil water storage, runoff and simulated discharge along with estimates of non-closure in the water budget. Using "baseline" water budgeting schemes in conjunction with atmospheric reanalyses and pre-EOS satellite data, water budget fields were conjunction with atmospheric reanalyses and pre-EOS satellite data, water budget fields were compiled to provide historical time series. The goals as outlined in the original proposal can be summarized as follows: 1) Use EOS data to compile hydrologic products for the pan-Arctic terrestrial regions including snowcover/snow water equivalent (SSM/A MODIS, AMSR) and near-surface freeze/thaw dynamics (Sea Winds on QuikSCAT and ADEOS I4 SSMI and AMSR). 2) Implement Arctic-RIMS to use EOS data streams, allied fields and hydrologic models to produce allied outputs that fully characterize pan-Arctic terrestrial and aerological water budgets. 3) Compile hydrologically-based historical products providing a long-term baseline of spatial and temporal variability in the water cycle.

ArcticDEM; A Publically Available, High Resolution Elevation Model of the Arctic

NASA Astrophysics Data System (ADS)

Morin, Paul; Porter, Claire; Cloutier, Michael; Howat, Ian; Noh, Myoung-Jong; Willis, Michael; Bates, Brian; Willamson, Cathleen; Peterman, Kennith

2016-04-01

A Digital Elevation Model (DEM) of the Arctic is needed for a large number of reasons, including: measuring and understanding rapid, ongoing changes to the Arctic landscape resulting from climate change and human use and mitigation and adaptation planning for Arctic communities. The topography of the Arctic is more poorly mapped than most other regions of Earth due to logistical costs and the limits of satellite missions with low-latitude inclinations. A convergence of civilian, high-quality sub-meter stereo imagery; petascale computing and open source photogrammetry software has made it possible to produce a complete, very high resolution (2 to 8-meter posting), elevation model of the Arctic. A partnership between the US National Geospatial-intelligence Agency and a team led by the US National Science Foundation funded Polar Geospatial Center is using stereo imagery from DigitalGlobe's Worldview-1, 2 and 3 satellites and the Ohio State University's Surface Extraction with TIN-based Search-space Minimization (SETSM) software running on the University of Illinois's Blue Water supercomputer to address this challenge. The final product will be a seemless, 2-m posting digital surface model mosaic of the entire Arctic above 60 North including all of Alaska, Greenland and Kamchatka. We will also make available the more than 300,000 individual time-stamped DSM strip pairs that were used to assemble the mosaic. The Arctic DEM will have a vertical precision of better than 0.5m and can be used to examine changes in land surfaces such as those caused by permafrost degradation or the evolution of arctic rivers and floodplains. The data set can also be used to highlight changing geomorphology due to Earth surface mass transport processes occurring in active volcanic and glacial environments. When complete the ArcticDEM will catapult the Arctic from the worst to among the best mapped regions on Earth.

Live from the Arctic

NASA Astrophysics Data System (ADS)

Warnick, W. K.; Haines-Stiles, G.; Warburton, J.; Sunwood, K.

2003-12-01

For reasons of geography and geophysics, the poles of our planet, the Arctic and Antarctica, are places where climate change appears first: they are global canaries in the mine shaft. But while Antarctica (its penguins and ozone hole, for example) has been relatively well-documented in recent books, TV programs and journalism, the far North has received somewhat less attention. This project builds on and advances what has been done to date to share the people, places, and stories of the North with all Americans through multiple media, over several years. In a collaborative project between the Arctic Research Consortium of the United States (ARCUS) and PASSPORT TO KNOWLEDGE, Live from the Arctic will bring the Arctic environment to the public through a series of primetime broadcasts, live and taped programming, interactive virtual field trips, and webcasts. The five-year project will culminate during the 2007-2008 International Polar Year (IPY). Live from the Arctic will: A. Promote global understanding about the value and world -wide significance of the Arctic, B. Bring cutting-edge research to both non-formal and formal education communities, C. Provide opportunities for collaboration between arctic scientists, arctic communities, and the general public. Content will focus on the following four themes. 1. Pan-Arctic Changes and Impacts on Land (i.e. snow cover; permafrost; glaciers; hydrology; species composition, distribution, and abundance; subsistence harvesting) 2. Pan-Arctic Changes and Impacts in the Sea (i.e. salinity, temperature, currents, nutrients, sea ice, marine ecosystems (including people, marine mammals and fisheries) 3. Pan-Arctic Changes and Impacts in the Atmosphere (i.e. precipitation and evaporation; effects on humans and their communities) 4. Global Perspectives (i.e. effects on humans and communities, impacts to rest of the world) In The Earth is Faster Now, a recent collection of comments by members of indigenous arctic peoples, arctic

The Age of the Arctic.

ERIC Educational Resources Information Center

Young, Oran R.

1986-01-01

Examines trends related to exploration in the Arctic by considering: (1) technology and military strategies; (2) foreign policy and the Arctic; (3) Arctic industrialization; (4) the Arctic policy agenda; and (5) recent United States initiatives in this region. (JN)

Arctic Strato-Mesospheric Temperature and Wind Variations

NASA Technical Reports Server (NTRS)

Schmidlin, F. J.; Goldberg, R. A.

2004-01-01

Upper stratosphere and mesosphere rocket measurements are actively used to investigate interaction between the neutral, electrical, and chemical atmospheres and between lower and upper layers of these regions. Satellite temperature measurements from HALOE and from inflatable falling spheres complement each other and allow illustrations of the annual cycle to 85 km altitude. Falling sphere wind and temperature measurements reveal variability that differs as a function of altitude, location, and time. We discuss the state of the Arctic atmosphere during the summer 2002 (Andoya, Norway) and winter 2003 (ESRANGE, Sweden) campaigns of MaCWAVE. Balloon-borne profiles to 30 km altitude and sphere profiles between 50 and 90 km show unique small-scale structure. Nonetheless, there are practical implications that additional measurements are very much needed to complete the full vertical profile picture. Our discussion concentrates on the distribution of temperature and wind and their variability. However, reliable measurements from other high latitude NASA programs over a number of years are available to help properly calculate mean values and the distribution of the individual measurements. Since the available rocket data in the Arctic's upper atmosphere are sparse the results we present are basically a snapshot of atmospheric structure.

Evaluation of Cloud Fraction and Radiative Fluxes in Recent Reanalyses over the Arctic using Surface and Satellite Observations

NASA Astrophysics Data System (ADS)

Zib, B.; Dong, X.; Xi, B.; Kennedy, A. D.

2010-12-01

Reanalysis datasets can be an essential tool for investigating numerous climate parameters, especially in data-sparse regions like the Arctic. Where long-term continuous data is limited, reanalyses offer a resource for the recognition and analysis of change in a sensitive and complex coupled Arctic climate system. A study focused on the evaluation and intercomparison of four relatively new global reanalysis datasets will be conducted. The four new reanalyses being investigated include: (i) NASA-MERRA, (ii) NCEP-CFS, (iii) NOAA-20CR, and (iv) NCEP-DOE II. In this study, the cloud fraction and TOA radiative fluxes simulated from four reanalyses over the entire Arctic region will be compared with those derived from NASA MODIS and CERES sensors during the period 2000-2008. The surface radiative fluxes derived in each reanalysis will also be compared and validated by the BSRN surface observations during the period 1994-2008. The high latitude BSRN sites used in this study are Barrow, Alaska (BAR) and Ny Alesund, Svalbard, Norway (NYA). BSRN offers high time resolution solar and atmospheric radiation measurements from high accuracy instruments that provide a baseline for validating reanalysis estimates of surface radiation. In addition to downwelling radiation fluxes, cloud fraction from the reanalyses will also be evaluated by the Vaisala ceilometer derived cloud fraction at the Barrow, AK site. The ultimate goal of this study is to quantitatively estimate the uncertainties or biases of cloud fraction and TOA and surface radiative fluxes derived from four different recent reanalyses using highly qualified long-term surface and satellite observations as ground truth over the Arctic region.

Arctic science input wanted

NASA Astrophysics Data System (ADS)

The Arctic Research and Policy Act (Eos, June 26, 1984, p. 412) was signed into law by President Ronald Reagan this past July. One of its objectives is to develop a 5-year research plan for the Arctic. A request for input to this plan is being issued this week to nearly 500 people in science, engineering, and industry.To promote Arctic research and to recommend research policy in the Arctic, the new law establishes a five-member Arctic Research Commission, to be appointed by the President, and establishes an Interagency Arctic Research Policy Committee, to be composed of representatives from nearly a dozen agencies having interests in the region. The commission will make policy recommendations, and the interagency committee will implement those recommendations. The National Science Foundation (NSF) has been designated as the lead agency of the interagency committee.

Arctic Rabies – A Review

PubMed Central

Mørk, Torill; Prestrud, Pål

2004-01-01

Rabies seems to persist throughout most arctic regions, and the northern parts of Norway, Sweden and Finland, is the only part of the Arctic where rabies has not been diagnosed in recent time. The arctic fox is the main host, and the same arctic virus variant seems to infect the arctic fox throughout the range of this species. The epidemiology of rabies seems to have certain common characteristics in arctic regions, but main questions such as the maintenance and spread of the disease remains largely unknown. The virus has spread and initiated new epidemics also in other species such as the red fox and the racoon dog. Large land areas and cold climate complicate the control of the disease, but experimental oral vaccination of arctic foxes has been successful. This article summarises the current knowledge and the typical characteristics of arctic rabies including its distribution and epidemiology. PMID:15535081

Assessing performance of gravity models in the Arctic and the implications for polar oceanography

NASA Astrophysics Data System (ADS)

Thomas, S. F.; McAdoo, D. C.; Farrell, S. L.; Brozena, J. M.; Childers, V. A.; Ziebart, M. K.; Shepherd, A.

2014-12-01

The circulation of the Arctic Ocean is of great interest to both the oceanographic and cryospheric communities. Understanding both the steady state and variations of this circulation is essential to building our knowledge of Arctic climate. With the advent of high inclination altimeter missions such as CryoSat and ICESat, it is now feasible to produce Mean Dynamic Topography (MDT) products for the region, which allow a comprehensive investigation of geostrophic currents. However, the accuracy of these products is largely limited by our knowledge of the marine geoid in the Arctic. There are a number of publicly available gravity models commonly used to derive the geoid. These use different combinations of available data (satellite gravimetry, altimetry, laser ranging, and in-situ) and are calculated using different mathematical techniques. However, the effect of these differences on the real world performance of these models when used for oceanographic studies in the Arctic is not well known. Given the unique problems for gravimetry in the region (especially data gaps) and their potential impact on MDT products, it is especially important that the relative performance of these models be assessed We consider the needs of the "end user" satellite oceanographer in the Arctic with respect to gravimetry, and the relationship between the precision of gravity data and the accuracy of a final MDT/current velocity product. Using high-precision aerogravity data collected over 3 years of campaigns by NASA's Operation IceBridge we inter-compare 10 of the leading gravity models and assess their performance in the Arctic. We also use historical data from campaigns flown by the US Naval Research Laboratory (NRL) to demonstrate the impact of gravity errors on MDT products. We describe how gravity models for the region might be improved in the future, in an effort to maximize the level at which Arctic currents may be resolved.

The 1994 Arctic Ocean Section. The First Major Scientific Crossing of the Arctic Ocean,

DTIC Science & Technology

1996-09-01

contribute to the international effort to better understand the role of the Arctic Ocean in the global carbon cycle and climate change. Summar...Barium Distributions in the Arctic Ocean ? ........................ 32 Biology and the Carbon Cycle Cycling of Organic Carbon in the Central Arctic...of Heterotrophic Bacteria and Protists in the Arctic Ocean Carbon Cycle............. 40

Seasonal Clear-Sky Flux and Cloud Radiative Effect Anomalies in the Arctic Atmospheric Column Associated with the Arctic Oscillation and Arctic Dipole

NASA Technical Reports Server (NTRS)

Hegyi, Bradley M.; Taylor, Patrick C.

2017-01-01

The impact of the Arctic Oscillation (AO) and Arctic Dipole (AD) on the radiative flux into the Arctic mean atmospheric column is quantified. 3-month-averaged AO and AD indices are regressed with corresponding surface and top-of-atmosphere (TOA) fluxes from the CERES-SFC and CERES-TOA EBAF datasets over the period 2000-2014. An increase in clear-sky fluxes into the Arctic mean atmospheric column during fall is the largest net flux anomaly associated with AO, primarily driven by a positive net longwave flux anomaly (i.e. increase of net flux into the atmospheric column) at the surface. A decrease in the Arctic mean atmospheric column cloud radiative effect during winter and spring is the largest flux anomaly associated with AD, primarily driven by a change in the longwave cloud radiative effect at the surface. These prominent responses to AO and AD are widely distributed across the ice-covered Arctic, suggesting that the physical process or processes that bring about the flux change associated with AO and AD are distributed throughout the Arctic.

Arctic Climate Systems Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ivey, Mark D.; Robinson, David G.; Boslough, Mark B.

2015-03-01

This study began with a challenge from program area managers at Sandia National Laboratories to technical staff in the energy, climate, and infrastructure security areas: apply a systems-level perspective to existing science and technology program areas in order to determine technology gaps, identify new technical capabilities at Sandia that could be applied to these areas, and identify opportunities for innovation. The Arctic was selected as one of these areas for systems level analyses, and this report documents the results. In this study, an emphasis was placed on the arctic atmosphere since Sandia has been active in atmospheric research in themore » Arctic since 1997. This study begins with a discussion of the challenges and benefits of analyzing the Arctic as a system. It goes on to discuss current and future needs of the defense, scientific, energy, and intelligence communities for more comprehensive data products related to the Arctic; assess the current state of atmospheric measurement resources available for the Arctic; and explain how the capabilities at Sandia National Laboratories can be used to address the identified technological, data, and modeling needs of the defense, scientific, energy, and intelligence communities for Arctic support.« less

Connecting Arctic Research Across Boundaries through the Arctic Research Consortium of the United States (ARCUS)

NASA Astrophysics Data System (ADS)

Rich, R. H.; Myers, B.; Wiggins, H. V.; Zolkos, J.

2017-12-01

The complexities inherent in Arctic research demand a unique focus on making connections across the boundaries of discipline, institution, sector, geography, knowledge system, and culture. Since 1988, ARCUS has been working to bridge these gaps through communication, coordination, and collaboration. Recently, we have worked with partners to create a synthesis of the Arctic system, to explore the connectivity across the Arctic research community and how to strengthen it, to enable the community to have an effective voice in research funding policy, to implement a system for Arctic research community knowledge management, to bridge between global Sea Ice Prediction Network researchers and the science needs of coastal Alaska communities through the Sea Ice for Walrus Outlook, to strengthen ties between Polar researchers and educators, and to provide essential intangible infrastructure that enables cost-effective and productive research across boundaries. Employing expertise in managing for collaboration and interdisciplinarity, ARCUS complements and enables the work of its members, who constitute the Arctic research community and its key stakeholders. As a member-driven organization, everything that ARCUS does is achieved through partnership, with strong volunteer leadership of each activity. Key organizational partners in the United States include the U.S. Arctic Research Commission, Interagency Arctic Research Policy Committee, National Academy of Sciences Polar Research Board, and the North Slope Science Initiative. Internationally, ARCUS maintains strong bilateral connections with similarly focused groups in each Arctic country (and those interested in the Arctic), as well as with multinational organizations including the International Arctic Science Committee, the Association of Polar Early Career Educators, the University of the Arctic, and the Arctic Institute of North America. Currently, ARCUS is applying the best practices of the science of team science

Study of Environmental Arctic Change (SEARCH): Scientific Understanding of Arctic Environmental Change to Help Society Understand and Respond to a Rapidly Changing Arctic.

NASA Astrophysics Data System (ADS)

Wiggins, H. V.; Myers, B.

2015-12-01

The Study of Environmental Arctic Change (SEARCH) is a U.S. program with a mission to provide a foundation of Arctic change science through collaboration with the research community, funding agencies, and other stakeholders. To achieve this mission, SEARCH: Generates and synthesizes research findings and promotes Arctic science and scientific discovery across disciplines and among agencies. Identifies emerging issues in Arctic environmental change. Provides scientific information to Arctic stakeholders, policy-makers, and the public to help them understand and respond to arctic environmental change. Facilitates research activities across local-to-global scales, with an emphasis on addressing needs of decision-makers. Collaborates with national and international science programs integral to SEARCH goals. This poster presentation will present SEARCH activities and plans, highlighting those focused on providing information for decision-makers. http://www.arcus.org/search

The Drivers of the CH4 Seasonal Cycle in the Arctic and What Long-Term Observations of CH4 Imply About Trends in Arctic CH4 Fluxes

NASA Astrophysics Data System (ADS)

Sweeney, C.; Karion, A.; Bruhwiler, L.; Miller, J. B.; Wofsy, S. C.; Miller, C. E.; Chang, R. Y.; Dlugokencky, E. J.; Daube, B.; Pittman, J. V.; Dinardo, S. J.

2012-12-01

The large seasonal change in the atmospheric column for CH4 in the Arctic is driven by two dominant processes: transport of CH4 from low latitudes and surface emissions throughout the Arctic region. The NOAA ESRL Carbon Cycle Group Aircraft Program along with the NASA funded Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) have initiated an effort to better understand the factors controlling the seasonal changes in the mole fraction of CH4 in the Arctic with a multi-scale aircraft observing network in Alaska. The backbone of this network is multi-species flask sampling from 500 to 8000 masl that has been conducted every two weeks for the last 10 years over Poker Flat, AK. In addition regular profiles at the interior Alaska site at Poker Flat, NOAA has teamed up with the United States Coast Guard to make profiling flights with continuous observations of CO2, CO, CH4 and Ozone between Kodiak and Barrow every 2 weeks. More recently, CARVE has significantly added to this observational network with targeted flights focused on exploring the variability of CO2, CH4 and CO in the boundary layer both in the interior and the North Slope regions of Alaska. Taken together with the profiling of HIAPER Pole-to-Pole Observations (HIPPO), ground sites at Barrow and a new CARVE interior Alaska surface site just north of Fairbanks, AK, we now have the ability to investigate the full evolution of the seasonal cycle in the Arctic using both the multi-scale sampling offered by the different aircraft platforms as well as the multi-species sampling offered by in-situ and flask sampling. The flasks also provide a valuable tie-point between different platforms so that spatial and temporal gradients can be properly interpreted. In the context of the seasonal cycle observed by the aircraft platforms we will look at long term ground observations over the last 20 years to assess changes in Arctic CH4 emissions which have occurred as a result of 0.6C/decade changes in mean surface

Boreal forest fire emissions in fresh Canadian smoke plumes: C1-C10 volatile organic compounds (VOCs), CO2, CO, NO2, NO, HCN and CH3CN

Treesearch

I. J. Simpson; S. K. Akagi; B. Barletta; N. J. Blake; Y. Choi; G. S. Diskin; A. Fried; H. E. Fuelberg; S. Meinardi; F. S. Rowland; S. A. Vay; A. J. Weinheimer; P. O. Wennberg; P. Wiebring; A. Wisthaler; M. Yang; R. J. Yokelson; D. R. Blake

2011-01-01

Boreal regions comprise about 17% of the global land area, and they both affect and are influenced by climate change. To better understand boreal forest fire emissions and plume evolution, 947 whole air samples were collected aboard the NASA DC-8 research aircraft in summer 2008 as part of the ARCTAS-B field mission, and analyzed for 79 non-methane volatile organic...

SEARCH: Study of Environmental Arctic Change--A System-scale, Cross-disciplinary Arctic Research Program

NASA Astrophysics Data System (ADS)

Shnoro, R. S.; Eicken, H.; Francis, J. A.; Scambos, T. A.; Schuur, E. A.; Straneo, F.; Wiggins, H. V.

2013-12-01

SEARCH is an interdisciplinary, interagency program that works with academic and government agency scientists and stakeholders to plan, conduct, and synthesize studies of Arctic change. Over the past three years, SEARCH has developed a new vision and mission, a set of prioritized cross-disciplinary 5-year goals, an integrated set of activities, and an organizational structure. The vision of SEARCH is to provide scientific understanding of arctic environmental change to help society understand and respond to a rapidly changing Arctic. SEARCH's 5-year science goals include: 1. Improve understanding, advance prediction, and explore consequences of changing Arctic sea ice. 2. Document and understand how degradation of near-surface permafrost will affect Arctic and global systems. 3. Improve predictions of future land-ice loss and impacts on sea level. 4. Analyze societal and policy implications of Arctic environmental change. Action Teams organized around each of the 5-year goals will serve as standing groups responsible for implementing specific goal activities. Members will be drawn from academia, different agencies and stakeholders, with a range of disciplinary backgrounds and perspectives. 'Arctic Futures 2050' scenarios tasks will describe plausible future states of the arctic system based on recent trajectories and projected changes. These scenarios will combine a range of data including climate model output, paleo-data, results from data synthesis and systems modeling, as well as expert scientific and traditional knowledge. Current activities include: - Arctic Observing Network (AON) - coordinating a system of atmospheric, land- and ocean-based environmental monitoring capabilities that will significantly advance our observations of arctic environmental conditions. - Arctic Sea Ice Outlook - an international effort that provides monthly summer reports synthesizing community estimates of the expected sea ice minimum. A newly-launched Sea Ice Prediction Network

Dynamical mechanisms of Arctic amplification.

PubMed

Dethloff, Klaus; Handorf, Dörthe; Jaiser, Ralf; Rinke, Annette; Klinghammer, Pia

2018-05-12

The Arctic has become a hot spot of climate change, but the nonlinear interactions between regional and global scales in the coupled climate system responsible for Arctic amplification are not well understood and insufficiently described in climate models. Here, we compare reanalysis data with model simulations for low and high Arctic sea ice conditions to identify model biases with respect to atmospheric Arctic-mid-latitude linkages. We show that an appropriate description of Arctic sea ice forcing is able to reproduce the observed winter cooling in mid-latitudes as result of improved tropospheric-stratospheric planetary wave propagation triggering a negative phase of the Arctic Oscillation/North Atlantic Oscillation in late winter. © 2018 New York Academy of Sciences.

Pan-Arctic observations in GRENE Arctic Climate Change Research Project and its successor

NASA Astrophysics Data System (ADS)

Yamanouchi, Takashi

2016-04-01

We started a Japanese initiative - "Arctic Climate Change Research Project" - within the framework of the Green Network of Excellence (GRENE) Program, funded by the Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT), in 2011. This Project targeted understanding and forecasting "Rapid Change of the Arctic Climate System and its Global Influences." Four strategic research targets are set by the Ministry: 1. Understanding the mechanism of warming amplification in the Arctic; 2. Understanding the Arctic climate system for global climate and future change; 3. Evaluation of the impacts of Arctic change on the weather and climate in Japan, marine ecosystems and fisheries; 4. Projection of sea ice distribution and Arctic sea routes. Through a network of universities and institutions in Japan, this 5-year Project involves more than 300 scientists from 39 institutions and universities. The National Institute of Polar Research (NIPR) works as the core institute and The Japan Agency for Marine- Earth Science and Technology (JAMSTEC) joins as the supporting institute. There are 7 bottom up research themes approved: the atmosphere, terrestrial ecosystems, cryosphere, greenhouse gases, marine ecology and fisheries, sea ice and Arctic sea routes and climate modeling, among 22 applications. The Project will realize multi-disciplinal study of the Arctic region and connect to the projection of future Arctic and global climatic change by modeling. The project has been running since the beginning of 2011 and in those 5 years pan-Arctic observations have been carried out in many locations, such as Svalbard, Russian Siberia, Alaska, Canada, Greenland and the Arctic Ocean. In particular, 95 GHz cloud profiling radar in high precision was established at Ny-Ålesund, Svalbard, and intensive atmospheric observations were carried out in 2014 and 2015. In addition, the Arctic Ocean cruises by R/V "Mirai" (belonging to JAMSTEC) and other icebreakers belonging to other

Potential for an Arctic-breeding migratory bird to adjust spring migration phenology to Arctic amplification.

PubMed

Lameris, Thomas K; Scholten, Ilse; Bauer, Silke; Cobben, Marleen M P; Ens, Bruno J; Nolet, Bart A

2017-10-01

Arctic amplification, the accelerated climate warming in the polar regions, is causing a more rapid advancement of the onset of spring in the Arctic than in temperate regions. Consequently, the arrival of many migratory birds in the Arctic is thought to become increasingly mismatched with the onset of local spring, consequently reducing individual fitness and potentially even population levels. We used a dynamic state variable model to study whether Arctic long-distance migrants can advance their migratory schedules under climate warming scenarios which include Arctic amplification, and whether such an advancement is constrained by fuel accumulation or the ability to anticipate climatic changes. Our model predicts that barnacle geese Branta leucopsis suffer from considerably reduced reproductive success with increasing Arctic amplification through mistimed arrival, when they cannot anticipate a more rapid progress of Arctic spring from their wintering grounds. When geese are able to anticipate a more rapid progress of Arctic spring, they are predicted to advance their spring arrival under Arctic amplification up to 44 days without any reproductive costs in terms of optimal condition or timing of breeding. Negative effects of mistimed arrival on reproduction are predicted to be somewhat mitigated by increasing summer length under warming in the Arctic, as late arriving geese can still breed successfully. We conclude that adaptation to Arctic amplification may rather be constrained by the (un)predictability of changes in the Arctic spring than by the time available for fuel accumulation. Social migrants like geese tend to have a high behavioural plasticity regarding stopover site choice and migration schedule, giving them the potential to adapt to future climate changes on their flyway. © 2017 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

Estimating Vegetation Height from WorldView-02 and ArcticDEM Data for Broad Ecological Applications

NASA Astrophysics Data System (ADS)

Meddens, A. J.; Vierling, L. A.; Eitel, J.; Jennewein, J. S.; White, J. C.; Wulder, M.

2017-12-01

Boreal and arctic regions are warming at an unprecedented rate, and at a rate higher than in other regions across the globe. Ecological processes are highly responsive to temperature and therefore substantial changes in these northern ecosystems are expected. Recently, NASA initiated the Arctic-Boreal Vulnerability Experiment (ABoVE), which is a large-scale field campaign that aims to gain a better understanding of how the arctic responds to environmental change. High-resolution data products that quantify vegetation structure and function will improve efforts to assess these environmental change impacts. Our objective was to develop and test an approach that allows for mapping vegetation height at a 5m grid cell resolution across the ABoVE domain. To accomplish this, we selected three study areas across a north-south gradient in Alaska, representing an area of approximately 130 km2. We developed a RandomForest modeling approach for predicting vegetation height using the ArcticDEM (a digital surface model produced across the Arctic by the Polar Geospatial Center) and high-resolution multispectral satellite data (WorldView-2) in conjunction with aerial lidar data for calibration and validation. Vegetation height was successfully predicted across the three study areas and evaluated using an independent dataset, with R2 ranging from 0.58 to 0.76 and RMSEs ranging from 1.8 to 2.4 m. This predicted vegetation height dataset also led to the development of a digital terrain model using the ArcticDEM digital surface model by removing canopy heights from the surface heights. Our results show potential to establish a high resolution pan-arctic vegetation height map, which will provide useful information to a broad range of ongoing and future ecological research in high northern latitudes.

Contemporary Arctic Sea Level

NASA Astrophysics Data System (ADS)

Cazenave, A. A.

2017-12-01

During recent decades, the Arctic region has warmed at a rate about twice the rest of the globe. Sea ice melting is increasing and the Greenland ice sheet is losing mass at an accelerated rate. Arctic warming, decrease in the sea ice cover and fresh water input to the Arctic ocean may eventually impact the Arctic sea level. In this presentation, we review our current knowledge of contemporary Arctic sea level changes. Until the beginning of the 1990s, Arctic sea level variations were essentially deduced from tide gauges located along the Russian and Norwegian coastlines. Since then, high inclination satellite altimetry missions have allowed measuring sea level over a large portion of the Arctic Ocean (up to 80 degree north). Measuring sea level in the Arctic by satellite altimetry is challenging because the presence of sea ice cover limits the full capacity of this technique. However adapted processing of raw altimetric measurements significantly increases the number of valid data, hence the data coverage, from which regional sea level variations can be extracted. Over the altimetry era, positive trend patterns are observed over the Beaufort Gyre and along the east coast of Greenland, while negative trends are reported along the Siberian shelf. On average over the Arctic region covered by satellite altimetry, the rate of sea level rise since 1992 is slightly less than the global mea sea level rate (of about 3 mm per year). On the other hand, the interannual variability is quite significant. Space gravimetry data from the GRACE mission and ocean reanalyses provide information on the mass and steric contributions to sea level, hence on the sea level budget. Budget studies show that regional sea level trends over the Beaufort Gyre and along the eastern coast of Greenland, are essentially due to salinity changes. However, in terms of regional average, the net steric component contributes little to the observed sea level trend. The sea level budget in the Arctic

Results of an Arctic Council survey on water and sanitation services in the Arctic.

PubMed

Bressler, Jonathan M; Hennessy, Thomas W

2018-12-01

As part of a project endorsed by the Arctic Council's Sustainable Development Working Group (SDWG), a survey was conducted to describe the current status of water, sanitation and hygiene (WASH) services in the Arctic region. The English language internet-based survey was open from April to September, 2016 and drew 142 respondents from seven Arctic nations. Respondents provided information on access to WASH services, notification requirements for water-related infectious diseases, and examples of environmental- or climate-change related events that impact the provision of WASH services. Many remote Arctic and sub-Arctic residents lack WASH services, and these disparities are often not reflected in national summary data. Environmental changes impacting WASH services were reported by respondents in every Arctic nation. Participants at an international conference co-sponsored by SDWG reviewed these results and provided suggestions for next steps to improve health of Arctic residents through improved access to water and sanitation services. Suggestions included ongoing reporting on WASH service availability in underserved populations to measure progress towards UN Sustainable Development Goal #6; evaluations of the health and economic consequences of disparities in WASH services; and Arctic-specific forums to share innovations in WASH technology, improved management and operations, and adaptation strategies for environmental or climate change.

Results of an Arctic Council survey on water and sanitation services in the Arctic

PubMed Central

Bressler, Jonathan M.; Hennessy, Thomas W.

2018-01-01

ABSTRACT As part of a project endorsed by the Arctic Council’s Sustainable Development Working Group (SDWG), a survey was conducted to describe the current status of water, sanitation and hygiene (WASH) services in the Arctic region. The English language internet-based survey was open from April to September, 2016 and drew 142 respondents from seven Arctic nations. Respondents provided information on access to WASH services, notification requirements for water-related infectious diseases, and examples of environmental- or climate-change related events that impact the provision of WASH services. Many remote Arctic and sub-Arctic residents lack WASH services, and these disparities are often not reflected in national summary data. Environmental changes impacting WASH services were reported by respondents in every Arctic nation. Participants at an international conference co-sponsored by SDWG reviewed these results and provided suggestions for next steps to improve health of Arctic residents through improved access to water and sanitation services. Suggestions included ongoing reporting on WASH service availability in underserved populations to measure progress towards UN Sustainable Development Goal #6; evaluations of the health and economic consequences of disparities in WASH services; and Arctic-specific forums to share innovations in WASH technology, improved management and operations, and adaptation strategies for environmental or climate change. PMID:29383987

Redefining U.S. Arctic Strategy

DTIC Science & Technology

2015-05-15

responsibility shifts 21 Barno, David and Nora Bensahel. The Anti-Access Challenge you’re not thinking...International Affairs 85, no. 6 (2009). 38 Barno, David and Nora Bensahel. THE ANTI-ACCESS CHALLENGE YOU’RE NOT THINKING ABOUT, 05 May 2015...and Rescue in the Arctic, 22 June 2011. Arctic Council Secretariat. About the Arctic Council, Arctic Council, 2011. Barno, David and Nora

USGS Arctic Science Strategy

USGS Publications Warehouse

Shasby, Mark; Smith, Durelle

2015-07-17

The United States is one of eight Arctic nations responsible for the stewardship of a polar region undergoing dramatic environmental, social, and economic changes. Although warming and cooling cycles have occurred over millennia in the Arctic region, the current warming trend is unlike anything recorded previously and is affecting the region faster than any other place on Earth, bringing dramatic reductions in sea ice extent, altered weather, and thawing permafrost. Implications of these changes include rapid coastal erosion threatening villages and critical infrastructure, potentially significant effects on subsistence activities and cultural resources, changes to wildlife habitat, increased greenhouse-gas emissions from thawing permafrost, threat of invasive species, and opening of the Arctic Ocean to oil and gas exploration and increased shipping. The Arctic science portfolio of the U.S. Geological Survey (USGS) and its response to climate-related changes focuses on landscapescale ecosystem and natural resource issues and provides scientific underpinning for understanding the physical processes that shape the Arctic. The science conducted by the USGS informs the Nation's resource management policies and improves the stewardship of the Arctic Region.

Understanding Mesoscale Land-Atmosphere Interactions in Arctic Region

NASA Astrophysics Data System (ADS)

Hong, X.; Wang, S.; Nachamkin, J. E.

2017-12-01

Land-atmosphere interactions in Arctic region are examined using the U.S. Navy Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS©*) with the Noah Land Surface Model (LSM). Initial land surface variables in COAMPS are interpolated from the real-time NASA Land Information System (LIS). The model simulations are configured for three nest grids with 27-9-3 km horizontal resolutions. The simulation period is set for October 2015 with 12-h data assimilation update cycle and 24-h integration length. The results are compared with those simulated without using LSM and evaluated with observations from ONR Sea State R/V Sikuliaq cruise and the North Slope of Alaska (NSA). There are complex soil and vegetation types over the surface for simulation with LSM, compared to without LSM simulation. The results show substantial differences in surface heat fluxes between bulk surface scheme and LSM, which may have an important impact on the sea ice evolution over the Arctic region. Evaluations from station data show surface air temperature and relative humidity have smaller biases for simulation using LSM. Diurnal variation of land surface temperature, which is necessary for physical processes of land-atmosphere, is also better captured than without LSM.

Radar studies of arctic ice and development of a real-time Arctic ice type identification system

NASA Technical Reports Server (NTRS)

Rouse, J. W., Jr.; Schell, J. A.; Permenter, J. A.

1973-01-01

Studies were conducted to develop a real-time Arctic ice type identification system. Data obtained by NASA Mission 126, conducted at Pt. Barrow, Alaska (Site 93) in April 1970 was analyzed in detail to more clearly define the major mechanisms at work affecting the radar energy illuminating a terrain cell of sea ice. General techniques for reduction of the scatterometer data to a form suitable for application of ice type decision criteria were investigated, and the electronic circuit requirements for implementation of these techniques were determined. Also, consideration of circuit requirements are extended to include the electronics necessary for analog programming of ice type decision algorithms. After completing the basic circuit designs a laboratory model was constructed and a preliminary evaluation performed. Several system modifications for improved performance are suggested. (Modified author abstract)

Patterns of CO2 and radiocarbon across high northern latitudes during International Polar Year 2008

NASA Astrophysics Data System (ADS)

Vay, S. A.; Choi, Y.; Vadrevu, K. P.; Blake, D. R.; Tyler, S. C.; Wisthaler, A.; Hecobian, A.; Kondo, Y.; Diskin, G. S.; Sachse, G. W.; Woo, J.-H.; Weinheimer, A. J.; Burkhart, J. F.; Stohl, A.; Wennberg, P. O.

2011-07-01

High-resolution in situ CO2 measurements were conducted aboard the NASA DC-8 aircraft during the ARCTAS/POLARCAT field campaign, a component of the wider 2007-2008 International Polar Year activities. Data were recorded during large-scale surveys spanning the North American sub-Arctic to the North Pole from 0.04 to 12 km altitude in spring and summer of 2008. Influences on the observed CO2 concentrations were investigated using coincident CO, black carbon, CH3CN, HCN, O3, C2Cl4, and Δ14CO2 data, and the FLEXPART model. In spring, the CO2 spatial distribution from 55°N to 90°N was largely determined by the long-range transport of air masses laden with Asian anthropogenic pollution intermingled with Eurasian fire emissions evidenced by the greater variability in the mid-to-upper troposphere. At the receptor site, the enhancement ratios of CO2 to CO in pollution plumes ranged from 27 to 80 ppmv ppmv-1 with the highest anthropogenic content registered in plumes sampled poleward of 80°N. In summer, the CO2 signal largely reflected emissions from lightning-ignited wildfires within the boreal forests of northern Saskatchewan juxtaposed with uptake by the terrestrial biosphere. Measurements within fresh fire plumes yielded CO2 to CO emission ratios of 4 to 16 ppmv ppmv-1 and a mean CO2 emission factor of 1698 ± 280 g kg-1 dry matter. From the 14C in CO2 content of 48 whole air samples, mean spring (46.6 ± 4.4‰) and summer (51.5 ± 5‰) Δ14CO2 values indicate a 5‰ seasonal difference. Although the northern midlatitudes were identified as the emissions source regions for the majority of the spring samples, depleted Δ14CO2 values were observed in <1% of the data set. Rather, ARCTAS Δ14CO2 observations (54%) revealed predominately a pattern of positive disequilibrium (1-7‰) with respect to background regardless of season owing to both heterotrophic respiration and fire-induced combustion of biomass. Anomalously enriched Δ14CO2 values (101-262‰) measured in

The Regional Influence of the Arctic Oscillation and Arctic Dipole on the Wintertime Arctic Surface Radiation Budget and Sea Ice Growth

NASA Technical Reports Server (NTRS)

Hegyi, Bradley M.; Taylor, Patrick C.

2017-01-01

An analysis of 2000-2015 monthly Clouds and the Earth's Radiant Energy System-Energy Balanced and Filled (CERES-EBAF) and Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA2) data reveals statistically significant fall and wintertime relationships between Arctic surface longwave (LW) radiative flux anomalies and the Arctic Oscillation (AO) and Arctic Dipole (AD). Signifying a substantial regional imprint, a negative AD index corresponds with positive downwelling clear-sky LW flux anomalies (greater than10W m(exp -2)) north of western Eurasia (0 deg E-120 deg E) and reduced sea ice growth in the Barents and Kara Seas in November-February. Conversely, a positive AO index coincides with negative clear-sky LW flux anomalies and minimal sea ice growth change in October-November across the Arctic. Increased (decreased) atmospheric temperature and water vapor coincide with the largest positive (negative) clear-sky flux anomalies. Positive surface LW cloud radiative effect anomalies also accompany the negative AD index in December-February. The results highlight a potential pathway by which Arctic atmospheric variability influences the regional surface radiation budget over areas of Arctic sea ice growth.

Biological Environmental Arctic Project (BEAP) Preliminary Data (Arctic West Summer 1986 Cruise).

DTIC Science & Technology

1986-11-01

predictive model of bioluminescence in near-surface arctic waters . Data were collected during Arctic West Summer 1986 from USCG POLAR STAR (WAGB 10). . %. J...2 20ODISTRIBUTION AVAILABILIT "Y OF ABSTRACT 21 ABSTRACT SECURITY CLASSIFICATION C]UNCLASSIFIED UNLIMITED SAME AS RPT C] DTIC USERS UNCLASSIFIED David...correlates for a predictive model of bioluminescence in near-surface arctic waters . - In previous years, these measurements were conducted from the USCG

Lidar Atmospheric Observatory in the Canadian Arctic

NASA Technical Reports Server (NTRS)

Ulitsky, Arkady; Wang, Tin-Yu; Flood, Martin; Smith, Brent

1992-01-01

During the last decade there have been growing concerns about a broad variety of atmospheric properties. Among these, a depletion of the stratospheric ozone layer has attracted considerable attention from the general public, politicians and scientists due to its vital impact for the entire global biosphere. One of the major warning signs was the discovery of the 'ozone hole' in the Antarctic region where the concentration of the ozone in the stratosphere was significantly reduced. At present the stratospheric ozone layer in this region is being continuously monitored by groups of scientists from around the world and numerous observations of the ozone layer on the global scale have clearly demonstrated the process of ozone depletion. Recent observations by NASA have shown significant depletion in the Arctic region. This paper provides an initial description of two lidars that are planned to be installed in a new observatory for atmospheric studies in the Canadian Arctic. This observatory is being constructed under the supervision of the Atmospheric Environment Services (AES) of Canada as a part of Green Plan - an initiative of the Federal Government of Canada. The station is located at Eureka on Ellesmere Island at a latitude of 80 degrees N and a longitude of 86 degrees W.

Arctic: A Friend Acting Strangely

Science.gov Websites

frequent. Explore the Arctic's changing climate. Discover what these changes mean for the Arctic, its warming in the Arctic by exploring how changes have been observed and documented by scientists and polar

Remote Sensing of Ocean Color in the High Arctic

NASA Technical Reports Server (NTRS)

Cota, G. F.; Platt, T.; Harrison, W. G.

1997-01-01

With four years of NASA SeaWiFS funding I established a completely new capability and expertise for in-water optical measurements nearly from scratch and with very little optical background. My first-year budget included only capital for a profiling spectral radiometer. Over the next 30 months we conducted six cruises and collected almost 300 optical profiles in challenging environments; many were collected from 21' launches. I also changed institutions during this period: it is very disruptive to move, set up a new lab, and hire and train new people, etc. We also did not have access to NASA funds for almost a year during the move because of difficulties in subcontracting and/or transferring funds. Nevertheless, we delivered data sets from six bio-optical cruises from three high latitude regions, although only two or three cruises from two areas were promised for our SeaWiFS research. The three Canadian Arctic field programs comprise the most comprehensive high latitude bio-optical and biogeochemical data sets in existence. Optical and pigment data from all six cruises have been submitted to NASA and are being included in the algorithm development test set. Additional data are still being submitted.

Atmospheric form drag over Arctic sea ice derived from high-resolution IceBridge elevation data

NASA Astrophysics Data System (ADS)

Petty, A.; Tsamados, M.; Kurtz, N. T.

2016-02-01

Here we present a detailed analysis of atmospheric form drag over Arctic sea ice, using high resolution, three-dimensional surface elevation data from the NASA Operation IceBridge Airborne Topographic Mapper (ATM) laser altimeter. Surface features in the sea ice cover are detected using a novel feature-picking algorithm. We derive information regarding the height, spacing and orientation of unique surface features from 2009-2014 across both first-year and multiyear ice regimes. The topography results are used to explicitly calculate atmospheric form drag coefficients; utilizing existing form drag parameterizations. The atmospheric form drag coefficients show strong regional variability, mainly due to variability in ice type/age. The transition from a perennial to a seasonal ice cover therefore suggest a decrease in the atmospheric form drag coefficients over Arctic sea ice in recent decades. These results are also being used to calibrate a recent form drag parameterization scheme included in the sea ice model CICE, to improve the representation of form drag over Arctic sea ice in global climate models.

Application of NASA's Advanced Life Support Technologies in Polar Regions

NASA Technical Reports Server (NTRS)

Bubenheim, David L.

1997-01-01

The problems of obtaining adequate pure drinking water and disposing of liquid and solid waste in the U.S Arctic, a region where virtually all water is frozen solid for much of the year, has led to unsanitary solutions. Sanitation and a safe water supply are particularly problems in rural villages. These villages are without running water and use plastic buckets for toilets. The outbreak of diseases is believed to be partially attributable to exposure to human waste and lack of sanitation. Villages with the most frequent outbreaks of disease are those in which running water is difficult to obtain. Waste is emptied into open lagoons, rivers, or onto the sea coast. It does not degrade rapidly and in addition to affecting human health, can be harmful to the fragile ecology of the Arctic and the indigenous wildlife and fish populations. Current practices for waste management and sanitation pose serious human hazards as well as threaten the environment. NASA's unique knowledge of water/wastewater treatment systems for extreme environments, identified in the Congressional Office of Technology Assessment report entitled An Alaskan Challenge: Native Villagt Sanitation, may offer practical solutions addressing the issues of safe drinking water and effective sanitation practices in rural villages. NASA's advanced life support technologies are being combined with Arctic science and engineering knowledge to address the unique needs of the remote communities of Alaska through the Advanced Life Systems for Extreme Environments (ALSEE) project. ALSEE is a collaborative effort involving the NASA, the State of Alaska, the University of Alaska, the North Slope Borough of Alaska, Ilisagvik College in Barrow and the National Science Foundation (NSF). The focus is a major issue in the State of Alaska and other areas of the Circumpolar North; the health and welfare of its people, their lives and the subsistence lifestyle in remote communities, economic opportunity, and care for the

NASA Operation IceBridge Flies Into the Classroom!

NASA Astrophysics Data System (ADS)

Kane, M.

2017-12-01

Field research opportunities for educators is leveraged as an invaluable tool to increase public engagement in climate research and the geosciences. We investigate the influence of educator's authentic fieldwork by highlighting the post-field impacts of a PolarTREC Teacher who participated in two campaigns, including NASA Operation IceBridge campaign over Antarctica in 2016. NASA's Operation IceBridge has hosted PolarTREC teachers since 2012, welcoming five teachers aboard multiple flights over the Arctic and one over Antarctica. The continuity of teacher inclusion in Operation IceBridge campaigns has facilitated a platform for collaborative curriculum development and revision, integration of National Snow and Ice Data Center (NSIDC) data into multiple classrooms, and given us a means whereby students can interact with science team members. I present impacts to my teaching and classrooms as I grapple with "Big Data" to allow students to work directly with lidar and radar data, I examine public outreach impacts through analytics from virtual networking tools including social media, NASA's Mission Tools Suite for Education, and field blog interactions.

Arctic Research Plan: FY2017-2021

USGS Publications Warehouse

Starkweather, Sandy; Jeffries, Martin O; Stephenson, Simon; Anderson, Rebecca D.; Jones, Benjamin M.; Loehman, Rachel A.; von Biela, Vanessa R.

2016-01-01

The United States is an Arctic nation—Americans depend on the Arctic for biodiversity and climate regulation and for natural resources. America’s Arctic—Alaska—is at the forefront of rapid climate, environmental, and socio-economic changes that are testing the resilience and sustainability of communities and ecosystems. Research to increase fundamental understanding of these changes is needed to inform sound, science-based decision- and policy-making and to develop appropriate solutions for Alaska and the Arctic region as a whole. Created by an Act of Congress in 1984, and since 2010 a subcommittee of the National Science and Technology Council (NSTC) in the Executive Office of the President, the Interagency Arctic Research Policy Committee (IARPC) plays a critical role in advancing scientific knowledge and understanding of the changing Arctic and its impacts far beyond the boundaries of the Arctic. Comprising 14 Federal agencies, offices, and departments, IARPC is responsible for the implementation of a 5-year Arctic Research Plan in consultation with the U.S. Arctic Research Commission, the Governor of the State of Alaska, residents of the Arctic, the private sector, and public interest groups.

The Immediacy of Arctic Change

NASA Astrophysics Data System (ADS)

Overland, J. E.; Wang, M.; Soreide, N. N.

2015-12-01

Ongoing temperature changes in the Arctic are large relative to lower latitudes; a process known as Arctic Amplification. Arctic temperatures have increased at least 3 times the rate of mid-latitude temperatures relative to the late 20th century, due to multiple interacting feedbacks driven by modest global change. Even if global temperature increases are contained to +2° C by 2040, Arctic (North of 60° N) monthly mean temperatures in fall will increase by +5° C. The Arctic is very likely to be sea ice free during summer before 2040, with the sea ice free duration limited to <5 months. Snow cover will be absent in May and June on most land masses. Whether these changes impact mid-latitude weather events is complex and controversial, as the time period for observing such linkages is short [<10 years] and involves understanding direct forcing by Arctic changes on a chaotic climatic system. Although chaotic internal variability dominates the dynamics of atmospheric circulation, Arctic thermodynamic influences can reinforce regional weather patterns. Extreme Arctic temperature events, as a combination of mean temperature increases combined with natural variability, will become common, nearing and exceeding previous thresholds. Such an event as an analog for the future was the +4° C anomalies for Alaska in November-December 2014 related to recent warm Pacific sea surface temperatures. Thus for the next few decades out to 2040, continuing rapid environmental changes in the Arctic are very likely, despite any mitigation activities, and the appropriate response is to plan for adaptation to meet these mean and extreme event changes. Mitigation is essential to forestall further disasters in the second half of the century. It is important to note such future rapid Arctic amplification, and the potential for environmental surprises, to support those making planning decisions and encourage action.

FIRE Arctic Clouds Experiment

NASA Technical Reports Server (NTRS)

Curry, J. A.; Hobbs, P. V.; King, M. D.; Randall, D. A.; Minnis, P.; Issac, G. A.; Pinto, J. O.; Uttal, T.; Bucholtz, A.; Cripe, D. G.;

Impacts and Feedbacks in a Warming Arctic: Engaging Diverse Learners in Geoscience Education and Research

NASA Astrophysics Data System (ADS)

Sparrow, Elena; Spellman, Katie; Fabbri, Cindy; Verbyla, David; Yoshikawa, Kenji; Fochesatto, Gilberto; Comiso, Josefino; Chase, Malinda; Jones, Debra; Bacsujlaky, Mara

2016-04-01

A warming climate has changed the timing of the seasons in the Arctic and elsewhere. Our project will engage learners in the investigation of the shifting seasons' impacts on vegetation, soils, hydrology, infrastructure, livelihoods, and communities and the feedbacks between these factors. Primary and secondary students, pre- and in-service teachers and lifelong learners will use historical and current National Aeronautics and Space Agency (NASA) data, NASA experts, and the Global Learning and Observations to Benefit the Environment (GLOBE) methods to help uncover the surprises from and consequences of earlier springs, warmer and later falls, changing ice cover, later freeze-up and earlier break-up of rivers and lakes. Key objectives are to: 1) provide new opportunities to bring NASA assets to learners of all ages, 2) enhance Science, Technology, Engineering and Mathematics (STEM) learning and understanding of the Earth system, 3) improve STEM instruction, 4) enhance STEM experience of undergraduate students, and 5) increase participation of groups historically underrepresented in STEM such as Native Americans who are also more vulnerable to climate change impacts. Incorporating issues of local importance with national and global implications, into educational experiences will make learning relevant which may be helpful to communities in developing strategies for adaptation. We intend to use NASA assets (e.g. MODIS snow data, NDVI, Cloudsat, and SMAP data), GLOBE methodologies (classic and new ground observations and measurements) to develop and deliver curriculum materials including culturally responsive learning activities, course/modules, professional development workshops, and educational experiences using best practices in pedagogy such as constructivism, inquiry- and place- based, interdisciplinary and systems approach, and cutting-edge technology to reach a variety of target audiences, while improving STEM education. Audiences include K-12 teachers and their

Investigating the Spectral Dependence of Biomass Burning Aerosol Optical Properties

NASA Astrophysics Data System (ADS)

Odwuor, A.; Corr, C.; Pusede, S.

2016-12-01

Aerosol optical properties, such as light absorption and scattering, are important for understanding how aerosols affect the global radiation budget and for comparison with data gathered from remote sensing. It has been established that the optical properties of aerosols are wavelength dependent, although some remote sensing measurements do not consider this. Airborne measurements of these optical properties were used to calculate the absorption Angstrom exponent, a parameter that characterizes the wavelength dependence of light absorption by aerosols, and single scattering albedo, which measures the relative magnitude of light scattering to total extinction (scattering and absorption combined). Aerosols produced by biomass burning in Saskatchewan, Canada in July 2008 and a forest fire in Southern California, U.S. in June 2016 were included in this analysis. These wildfires were sampled by the NASA DC-8 aircraft during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) and NASA Student Airborne Research Program (SARP) missions, respectively. Aerosol absorption was measured using a particle soot photometer (PSAP) at 470, 532 and 660 nm. Scattering was measured using a 3-wavelength (450, 550 and 700 nm) nephelometer. Absorption Angstrom exponents were calculated at 470 and 660 nm and single scattering albedos were calculated at 450 and 550 nm. Results of this study indicate that disregarding the wavelength dependence of organic aerosol can understate the positive radiative forcing (warming) associated with aerosol absorption.

Molecular epidemiological study of Arctic rabies virus isolates from Greenland and comparison with isolates from throughout the Arctic and Baltic regions.

PubMed

Mansfield, K L; Racloz, V; McElhinney, L M; Marston, D A; Johnson, N; Rønsholt, L; Christensen, L S; Neuvonen, E; Botvinkin, A D; Rupprecht, C E; Fooks, A R

2006-03-01

We report a molecular epidemiological study of rabies in Arctic countries by comparing a panel of novel Greenland isolates to a larger cohort of viral sequences from both Arctic and Baltic regions. Rabies virus isolates originating from wildlife (Arctic/red foxes, raccoon-dogs and reindeer), from domestic animals (dogs/cats) and from two human cases were investigated. The resulting 400 bp N-gene sequences were compared with isolates representing neighbouring Arctic or Baltic countries from North America, the former Soviet Union and Europe. Phylogenetic analysis demonstrated similarities between sequences from the Arctic and Arctic-like viruses, which were distinct from rabies isolates originating in the Baltic region of Europe, the Steppes in Russia and from North America. The Arctic-like group consist of isolates from India, Pakistan, southeast Siberia and Japan. The Arctic group was differentiated into two lineages, Arctic 1 and Arctic 2, with good bootstrap support. Arctic 1 is mainly comprised of Canadian isolates with a single fox isolate from Maine in the USA. Arctic 2 was further divided into sub-lineages: 2a/2b. Arctic 2a comprises isolates from the Arctic regions of Yakutia in northeast Siberia and Alaska. Arctic 2b isolates represent a biotype, which is dispersed throughout the Arctic region. The broad distribution of rabies in the Arctic regions including Greenland, Canada and Alaska provides evidence for the movement of rabies across borders.

Arctic freshwater synthesis: Introduction

NASA Astrophysics Data System (ADS)

Prowse, T.; Bring, A.; Mârd, J.; Carmack, E.

2015-11-01

In response to a joint request from the World Climate Research Program's Climate and Cryosphere Project, the International Arctic Science Committee, and the Arctic Council's Arctic Monitoring and Assessment Program, an updated scientific assessment has been conducted of the Arctic Freshwater System (AFS), entitled the Arctic Freshwater Synthesis (AFSΣ). The major reason for joint request was an increasing concern that changes to the AFS have produced, and could produce even greater, changes to biogeophysical and socioeconomic systems of special importance to northern residents and also produce extra-Arctic climatic effects that will have global consequences. Hence, the key objective of the AFSΣ was to produce an updated, comprehensive, and integrated review of the structure and function of the entire AFS. The AFSΣ was organized around six key thematic areas: atmosphere, oceans, terrestrial hydrology, terrestrial ecology, resources and modeling, and the review of each coauthored by an international group of scientists and published as separate manuscripts in this special issue of Journal of Geophysical Research-Biogeosciences. This AFSΣ—Introduction reviews the motivations for, and foci of, previous studies of the AFS, discusses criteria used to define the domain of the AFS, and details key characteristics of the definition adopted for the AFSΣ.

Changing Arctic ecosystems: ecology of loons in a changing Arctic

USGS Publications Warehouse

Uher-Koch, Brian; Schmutz, Joel; Whalen, Mary; Pearce, John M.

2014-01-01

The U.S. Geological Survey (USGS) Changing Arctic Ecosystems (CAE) initiative informs key resource management decisions for Arctic Alaska by providing scientific information on current and future ecosystem response to a changing climate. From 2010 to 2014, a key study area for the USGS CAE initiative has been the Arctic Coastal Plain of northern Alaska. This region has experienced rapid warming during the past 30 years, leading to the thawing of permafrost and changes to lake and river systems. These changes, and projections of continued change, have raised questions about effects on wildlife populations that rely on northern lake ecosystems, such as loons. Loons rely on freshwater lakes for nesting habitat and the fish and invertebrates inhabiting the lakes for food. Loons live within the National Petroleum Reserve-Alaska (NPR-A) on Alaska’s northern coast, where oil and gas development is expected to increase. Research by the USGS examines how breeding loons use the Arctic lake ecosystem and the capacity of loons to adapt to future landscape change.

Toward an Arctic Strategy

DTIC Science & Technology

2009-02-01

Arctic Sea Ice Extent6 Reduced ice pack area translates to less reflected solar energy, which further accelerates the ongoing melting process . Light... process , creating a vicious cycle where melting ice causes the remaining ice to melt faster.7 Modelers previously agreed that the Arctic Ocean could be...freight ports stand to benefit by shipping through the Arctic region.10 For example, an ocean voyage from Yokohama, Japan, to Hamburg, Germany via the

Genomics of Arctic cod

USGS Publications Warehouse

Wilson, Robert E.; Sage, George K.; Sonsthagen, Sarah A.; Gravley, Megan C.; Menning, Damian; Talbot, Sandra L.

2017-01-01

The Arctic cod (Boreogadus saida) is an abundant marine fish that plays a vital role in the marine food web. To better understand the population genetic structure and the role of natural selection acting on the maternally-inherited mitochondrial genome (mitogenome), a molecule often associated with adaptations to temperature, we analyzed genetic data collected from 11 biparentally-inherited nuclear microsatellite DNA loci and nucleotide sequence data from from the mitochondrial DNA (mtDNA) cytochrome b (cytb) gene and, for a subset of individuals, the entire mitogenome. In addition, due to potential of species misidentification with morphologically similar Polar cod (Arctogadus glacialis), we used ddRAD-Seq data to determine the level of divergence between species and identify species-specific markers. Based on the findings presented here, Arctic cod across the Pacific Arctic (Bering, Chukchi, and Beaufort Seas) comprise a single panmictic population with high genetic diversity compared to other gadids. High genetic diversity was indicated across all 13 protein-coding genes in the mitogenome. In addition, we found moderate levels of genetic diversity in the nuclear microsatellite loci, with highest diversity found in the Chukchi Sea. Our analyses of markers from both marker classes (nuclear microsatellite fragment data and mtDNA cytb sequence data) failed to uncover a signal of microgeographic genetic structure within Arctic cod across the three regions, within the Alaskan Beaufort Sea, or between near-shore or offshore habitats. Further, data from a subset of mitogenomes revealed no genetic differentiation between Bering, Chukchi, and Beaufort seas populations for Arctic cod, Saffron cod (Eleginus gracilis), or Walleye pollock (Gadus chalcogrammus). However, we uncovered significant differences in the distribution of microsatellite alleles between the southern Chukchi and central and eastern Beaufort Sea samples of Arctic cod. Finally, using ddRAD-Seq data, we

77 FR 31677 - Request for Public Comment on Interagency Arctic Research Policy Committee (IARPC) Arctic...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-29

... OFFICE OF SCIENCE AND TECHNOLOGY POLICY Request for Public Comment on Interagency Arctic Research Policy Committee (IARPC) Arctic Research Plan: FY2013-2017 May 22, 2012. ACTION: Request for public comment. SUMMARY: The Arctic Research and Policy Act of 1984 (ARPA), Public Law 98-373, established the...

The International Arctic Buoy Programme (IABP): A Cornerstone of the Arctic Observing Network

DTIC Science & Technology

2008-09-01

SEP 2008 2. REPORT TYPE 3. DATES COVERED 00-00-2008 to 00-00-2008 4. TITLE AND SUBTITLE The International Arctic Buoy Programme ( IABP ): A...Prescribed by ANSI Std Z39-18 The International Arctic Buoy Programme ( IABP ): A Cornerstone of the Arctic Observing Network Ignatius G. Rigor...changes in weather, climate and environment. It should be noted that many of these changes were first observed and studied using data from the IABP (http

Seasonality of global and Arctic black carbon processes in the Arctic Monitoring and Assessment Programme models: Global and Arctic Black Carbon Processes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mahmood, Rashed; von Salzen, Knut; Flanner, Mark

2016-06-22

This study quantifies black carbon (BC) processes in three global climate models and one chemistry transport model, with focus on the seasonality of BC transport, emissions, wet and dry deposition in the Arctic. In the models, transport of BC to the Arctic from lower latitudes is the major BC source for this region while Arctic emissions are very small. All models simulated a similar annual cycle of BC transport from lower latitudes to the Arctic, with maximum transport occurring in July. Substantial differences were found in simulated BC burdens and vertical distributions, with CanAM (NorESM) producing the strongest (weakest) seasonalmore » cycle. CanAM also has the shortest annual mean residence time for BC in the Arctic followed by SMHI-MATCH, CESM and NorESM. The relative contribution of wet and dry deposition rates in removing BC varies seasonally and is one of the major factors causing seasonal variations in BC burdens in the Arctic. Overall, considerable differences in wet deposition efficiencies in the models exist and are a leading cause of differences in simulated BC burdens. Results from model sensitivity experiments indicate that scavenging of BC in convective clouds acts to substantially increase the overall efficiency of BC wet deposition in the Arctic, which leads to low BC burdens and a more pronounced seasonal cycle compared to simulations without convective BC scavenging. In contrast, the simulated seasonality of BC concentrations in the upper troposphere is only weakly influenced by wet deposition in stratiform (layer) clouds whereas lower tropospheric concentrations are highly sensitive.« less

Arctic and Antarctic Sea Ice, 1978-1987: Satellite Passive-Microwave Observations and Analysis

NASA Technical Reports Server (NTRS)

Gloersen, Per; Campbell, William J.; Cavalieri, Donald J.; Comiso, Josefino C.; Parkinson, Claire L.; Zwally, H. Jay

1992-01-01

This book contains a description and analysis of the spatial and temporal variations in the Arctic and Antarctic sea ice covers from October 26, 1978 through August 20, 1987. It is based on data collected by the Scanning Multichannel Microwave Radiometer (SMMR) onboard the NASA Nimbus 7 satellite. The 8.8-year period, together with the 4 years of the Nimbus 5 Electrically Scanning Microwave Radiometer (ESMR) observations presented in two earlier volumes, comprises a sea ice record spanning almost 15 years.

Changes in Arctic and Boreal ecosystems of North America: Integrating Recent Results from the Field, Remote Sensing and Ecosystem Models

NASA Astrophysics Data System (ADS)

Goetz, S. J.; Rogers, B. M.; Mack, M. C.; Goulden, M.; Pastick, N. J.; Berner, L. T.; Fisher, J.

2017-12-01

The Arctic and boreal forest biomes have global significance in terms of climate feedbacks associated with land surface interactions with the atmosphere. Changes in Arctic tundra and boreal forest ecosystem productivity and fire disturbance feedbacks have been well documented in recent years, but findings are often only locally relevant and are sometimes inconsistent among research teams. Part of these inconsistencies lie in utilization of different data sets and time periods considered. Integrated approaches are thus needed to adequately address changes in these ecosystems in order to assess consistency and variability of change, as well as ecosystem vulnerability and resiliency across spatial and temporal scales. Ultimately this can best be accomplished via multiple lines of evidence including remote sensing, field measurements and various types of data-constrained models. We will discuss some recent results integrating multiple lines of evidence for directional ecosystem change in the Arctic and boreal forest biomes of North America. There is increasing evidence for widespread spatial and temporal variability in Arctic and boreal ecosystem productivity changes that are strongly influenced by cycles of changing fire disturbance severity and its longer-term implications (i.e legacy effects). Integrated, multi-approach research, like that currently underway as part of the NASA-led Arctic Boreal Vulnerability Experiment (above.nasa.gov), is an effective way to capture the complex mechanisms that drive patterns and directionality of ecosystem structure and function, and ultimately determine feedbacks to environmental change, particularly in the context of global climate change. Additional ongoing ABoVE research will improve our understanding of the consequences of environmental changes underway, as well as increase our confidence in making projections of the ecosystem responses, vulnerability and resilience to change. ABoVE will also build a lasting legacy of

Emergent Behavior of Arctic Precipitation in Response to Enhanced Arctic Warming

NASA Astrophysics Data System (ADS)

Anderson, Bruce T.; Feldl, Nicole; Lintner, Benjamin R.

2018-03-01

Amplified warming of the high latitudes in response to human-induced emissions of greenhouse gases has already been observed in the historical record and is a robust feature evident across a hierarchy of model systems, including the models of the Coupled Model Intercomparison Project Phase 5 (CMIP5). The main aims of this analysis are to quantify intermodel differences in the Arctic amplification (AA) of the global warming signal in CMIP5 RCP8.5 (Representative Concentration Pathway 8.5) simulations and to diagnose these differences in the context of the energy and water cycles of the region. This diagnosis reveals an emergent behavior between the energetic and hydrometeorological responses of the Arctic to warming: in particular, enhanced AA and its associated reduction in dry static energy convergence is balanced to first order by latent heating via enhanced precipitation. This balance necessitates increasing Arctic precipitation with increasing AA while at the same time constraining the magnitude of that precipitation increase. The sensitivity of the increase, 1.25 (W/m2)/K ( 240 (km3/yr)/K), is evident across a broad range of historical and projected AA values. Accounting for the energetic constraint on Arctic precipitation, as a function of AA, in turn informs understanding of both the sign and magnitude of hydrologic cycle changes that the Arctic may experience.

Arctic Security Considerations and the U.S. Navy’s Roadmap for the Arctic

DTIC Science & Technology

2010-01-01

observed in the sea, in the air, and on land. Indigenous Arctic people are facing relocation and loss of communities as sea-ice melt causes increased...sea-ice melting associated with global climate change has caused leadersfrom the United States and the international community to reconsider the...of the Navy as a valued partner by the joint, interagency, and international communities . THE CHANGING ARCTIC ENVIRONMENT The Arctic has long been a

The Arctic-Subarctic Sea Ice System is Entering a Seasonal Regime: Implications for Future Arctic Amplication

NASA Astrophysics Data System (ADS)

Haine, T. W. N.; Martin, T.

2017-12-01

The loss of Arctic sea ice is a conspicuous example of climate change. Climate models project ice-free conditions during summer this century under realistic emission scenarios, reflecting the increase in seasonality in ice cover. To quantify the increased seasonality in the Arctic-Subarctic sea ice system, we define a non-dimensional seasonality number for sea ice extent, area, and volume from satellite data and realistic coupled climate models. We show that the Arctic-Subarctic, i.e. the northern hemisphere, sea ice now exhibits similar levels of seasonality to the Antarctic, which is in a seasonal regime without significant change since satellite observations began in 1979. Realistic climate models suggest that this transition to the seasonal regime is being accompanied by a maximum in Arctic amplification, which is the faster warming of Arctic latitudes compared to the global mean, in the 2010s. The strong link points to a peak in sea-ice-related feedbacks that occurs long before the Arctic becomes ice-free in summer.

Arctic marine ecosystem contamination.

PubMed

Muir, D C; Wagemann, R; Hargrave, B T; Thomas, D J; Peakall, D B; Norstrom, R J

1992-07-15

The current state of knowledge of levels, spatial and temporal trends of contaminants in the Arctic marine ecosystem varies greatly among pollutants and among environmental compartments. Levels of polychlorinated biphenyls (PCBs), organochlorine (OC) pesticides and some heavy metals such as mercury and lead, in Arctic marine mammals and fish are relatively well documented because of the need for comparisons with biota in more polluted environments and interest in the contamination of native diets. Levels of heavy metals, alkanes, polyaromatic hydrocarbons (PAH) and OCs in the Arctic Ocean are comparable to uncontaminated ocean waters in the mid-latitudes. But concentrations of alpha- and gamma-hexachlorocyclohexane (HCHs) are higher in northern waters far removed from local sources, possibly because lower water temperature reduces transfer to the atmosphere. Bioaccumulation of OCs and heavy metals in Arctic marine food chains begins with epontic ice algae or phytoplankton in surface waters. Polychlorinated camphenes (PCC), PCBs, DDT- and chlordane-related compounds are the major OCs in marine fish, mammals and seabirds. Mean concentrations of most PCBs and OC pesticides in ringed seal (Phoca hispida) and polar bear (Ursus maritimus) populations in the Canadian Arctic are quite similar indicating a uniform geographic distribution of contamination, although alpha-HCH showed a distinct latitudinal gradient in bears due to higher levels in zones influenced by continental runoff. Ringed seals from Spitzbergen have higher levels of PCBs, total DDT and polychlorinated dioxins/furans (PCDD/PCDFs). In contrast to other OCs, PCDD/PCDFs in Canadian Arctic ringed seals and polar bears were higher in the east/central Arctic than at more southerly locations. Remarkably high cadmium levels are found in kidney and liver of narwhal (Monodons monoceros) from western Baffin Bay (mean of 63.5 micrograms g-1) and western Greenland waters (median of 39.5 micrograms g-1). Mercury

The Arctic zone: possibilities and risks of development

NASA Astrophysics Data System (ADS)

Sentsov, A.; Bolsunovskaya, Y.; Melnikovich, E.

2016-09-01

The authors analyze the Arctic region innovative possibilities from the perspective of political ideology and strategy. The Arctic region with its natural resources and high economic potential attracts many companies and it has become an important area of transnational development. At present, the Arctic region development is of great importance in terms of natural resource management and political system development. However, the most important development issue in the Arctic is a great risk of different countries’ competing interests in economic, political, and legal context. These are challenges for international partnership creating in the Arctic zone, Russian future model developing for the Arctic, and recognition of the Arctic as an important resource for the Russians. The Russian economic, military, and political expansion in the Arctic region has the potential to strengthen the national positions. The authors present interesting options for minimizing and eliminating political risks during the Arctic territories development and define an effective future planning model for the Russian Arctic.

The Arctic Coastal Erosion Problem

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frederick, Jennifer M.; Thomas, Matthew Anthony; Bull, Diana L.

Permafrost-dominated coastlines in the Arctic are rapidly disappearing. Arctic coastal erosion rates in the United States have doubled since the middle of the twentieth century and appear to be accelerating. Positive erosion trends have been observed for highly-variable geomorphic conditions across the entire Arctic, suggesting a major (human-timescale) shift in coastal landscape evolution. Unfortunately, irreversible coastal land loss in this region poses a threat to native, industrial, scientific, and military communities. The Arctic coastline is vast, spanning more than 100,000 km across eight nations, ten percent of which is overseen by the United States. Much of area is inaccessible bymore » all-season roads. People and infrastructure, therefore, are commonly located near the coast. The impact of the Arctic coastal erosion problem is widespread. Homes are being lost. Residents are being dispersed and their villages relocated. Shoreline fuel storage and delivery systems are at greater risk. The U.S. Department of Energy (DOE) and Sandia National Laboratories (SNL) operate research facilities along some of the most rapidly eroding sections of coast in the world. The U.S. Department of Defense (DOD) is struggling to fortify coastal radar sites, operated to ensure national sovereignty in the air, against the erosion problem. Rapid alterations to the Arctic coastline are facilitated by oceanographic and geomorphic perturbations associated with climate change. Sea ice extent is declining, sea level is rising, sea water temperature is increasing, and permafrost state is changing. The polar orientation of the Arctic exacerbates the magnitude and rate of the environmental forcings that facilitate coastal land area loss. The fundamental mechanics of these processes are understood; their non-linear combination poses an extreme hazard. Tools to accurately predict Arctic coastal erosion do not exist. To obtain an accurate predictive model, a coupling of the influences of

Arctic Collaborative Environment: A New Multi-National Partnership for Arctic Science and Decision Support

NASA Technical Reports Server (NTRS)

Laymon, Charles A,; Kress, Martin P.; McCracken, Jeff E.; Spehn, Stephen L.; Tanner, Steve

2011-01-01

The Arctic Collaborative Environment (ACE) project is a new international partnership for information sharing to meet the challenges of addressing Arctic. The goal of ACE is to create an open source, web-based, multi-national monitoring, analysis, and visualization decision-support system for Arctic environmental assessment, management, and sustainability. This paper will describe the concept, system architecture, and data products that are being developed and disseminated among partners and independent users through remote access.

The Arctic Marine Pulses Model: Linking Contiguous Domains in the Pacific Arctic Region

NASA Astrophysics Data System (ADS)

Moore, S. E.; Stabeno, P. J.

2016-02-01

The Pacific Arctic marine ecosystem extends from the northern Bering Sea, across the Chukchi and into the East Siberian and Beaufort seas. Food webs in this domain are short, a simplicity that belies the biophysical complexity underlying trophic linkages from primary production to humans. Existing biophysical models, such as pelagic-benthic coupling and advective processes, provide frameworks for connecting certain aspects of the marine food web, but do not offer a full accounting of events that occur seasonally across the Pacific Arctic. In the course of the Synthesis of Arctic Research (SOAR) project, a holistic Arctic Marine Pulses (AMP) model was developed that depicts seasonal biophysical `pulses' across a latitudinal gradient, and linking four previously-described contiguous domains, including the: (i) Pacific-Arctic domain = the focal region; (ii) seasonal ice zone domain; (iii) Pacific marginal domain; and (iv) riverine coastal domain. The AMP model provides a spatial-temporal framework to guide research on dynamic ecosystem processes during this period of rapid biophysical changes in the Pacific Arctic. Some of the processes included in the model, such as pelagic-benthic coupling in the Northern Bering and Chukchi seas, and advection and upwelling along the Beaufort shelf, are already the focus of sampling via the Distributed Biological Observatory (DBO) and other research programs. Other aspects such as biological processes associated with the seasonal ice zone and trophic responses to riverine outflow have received less attention. The AMP model could be enhanced by the application of visualization tools to provide a means to watch a season unfold in space and time. The capability to track sea ice dynamics and water masses and to move nutrients, prey and upper-trophic predators in space and time would provide a strong foundation for the development of predictive human-inclusive ecosystem models for the Pacific Arctic.

Tsunami in the Arctic

NASA Astrophysics Data System (ADS)

Kulikov, Evgueni; Medvedev, Igor; Ivaschenko, Alexey

2017-04-01

The severity of the climate and sparsely populated coastal regions are the reason why the Russian part of the Arctic Ocean belongs to the least studied areas of the World Ocean. In the same time intensive economic development of the Arctic region, specifically oil and gas industry, require studies of potential thread natural disasters that can cause environmental and technical damage of the coastal and maritime infrastructure of energy industry complex (FEC). Despite the fact that the seismic activity in the Arctic can be attributed to a moderate level, we cannot exclude the occurrence of destructive tsunami waves, directly threatening the FEC. According to the IAEA requirements, in the construction of nuclear power plants it is necessary to take into account the impact of all natural disasters with frequency more than 10-5 per year. Planned accommodation in the polar regions of the Russian floating nuclear power plants certainly requires an adequate risk assessment of the tsunami hazard in the areas of their location. Develop the concept of tsunami hazard assessment would be based on the numerical simulation of different scenarios in which reproduced the hypothetical seismic sources and generated tsunamis. The analysis of available geological, geophysical and seismological data for the period of instrumental observations (1918-2015) shows that the highest earthquake potential within the Arctic region is associated with the underwater Mid-Arctic zone of ocean bottom spreading (interplate boundary between Eurasia and North American plates) as well as with some areas of continental slope within the marginal seas. For the Arctic coast of Russia and the adjacent shelf area, the greatest tsunami danger of seismotectonic origin comes from the earthquakes occurring in the underwater Gakkel Ridge zone, the north-eastern part of the Mid-Arctic zone. In this area, one may expect earthquakes of magnitude Mw ˜ 6.5-7.0 at a rate of 10-2 per year and of magnitude Mw ˜ 7.5 at a

Missing pieces to modeling the Arctic-Boreal puzzle

NASA Astrophysics Data System (ADS)

Fisher, Joshua B.; Hayes, Daniel J.; Schwalm, Christopher R.; Huntzinger, Deborah N.; Stofferahn, Eric; Schaefer, Kevin; Luo, Yiqi; Wullschleger, Stan D.; Goetz, Scott; Miller, Charles E.; Griffith, Peter; Chadburn, Sarah; Chatterjee, Abhishek; Ciais, Philippe; Douglas, Thomas A.; Genet, Hélène; Ito, Akihiko; Neigh, Christopher S. R.; Poulter, Benjamin; Rogers, Brendan M.; Sonnentag, Oliver; Tian, Hanqin; Wang, Weile; Xue, Yongkang; Yang, Zong-Liang; Zeng, Ning; Zhang, Zhen

2018-02-01

NASA has launched the decade-long Arctic-Boreal Vulnerability Experiment (ABoVE). While the initial phases focus on field and airborne data collection, early integration with modeling activities is important to benefit future modeling syntheses. We compiled feedback from ecosystem modeling teams on key data needs, which encompass carbon biogeochemistry, vegetation, permafrost, hydrology, and disturbance dynamics. A suite of variables was identified as part of this activity with a critical requirement that they are collected concurrently and representatively over space and time. Individual projects in ABoVE may not capture all these needs, and thus there is both demand and opportunity for the augmentation of field observations, and synthesis of the observations that are collected, to ensure that science questions and integrated modeling activities are successfully implemented.

Arctic in Rapid Transition: Priorities for the future of marine and coastal research in the Arctic

NASA Astrophysics Data System (ADS)

Werner, Kirstin; Fritz, Michael; Morata, Nathalie; Keil, Kathrin; Pavlov, Alexey; Peeken, Ilka; Nikolopoulos, Anna; Findlay, Helen S.; Kędra, Monika; Majaneva, Sanna; Renner, Angelika; Hendricks, Stefan; Jacquot, Mathilde; Nicolaus, Marcel; O'Regan, Matt; Sampei, Makoto; Wegner, Carolyn

2016-09-01

Understanding and responding to the rapidly occurring environmental changes in the Arctic over the past few decades require new approaches in science. This includes improved collaborations within the scientific community but also enhanced dialogue between scientists and societal stakeholders, especially with Arctic communities. As a contribution to the Third International Conference on Arctic Research Planning (ICARPIII), the Arctic in Rapid Transition (ART) network held an international workshop in France, in October 2014, in order to discuss high-priority requirements for future Arctic marine and coastal research from an early-career scientists (ECS) perspective. The discussion encompassed a variety of research fields, including topics of oceanographic conditions, sea-ice monitoring, marine biodiversity, land-ocean interactions, and geological reconstructions, as well as law and governance issues. Participants of the workshop strongly agreed on the need to enhance interdisciplinarity in order to collect comprehensive knowledge about the modern and past Arctic Ocean's geo-ecological dynamics. Such knowledge enables improved predictions of Arctic developments and provides the basis for elaborate decision-making on future actions under plausible environmental and climate scenarios in the high northern latitudes. Priority research sheets resulting from the workshop's discussions were distributed during the ICARPIII meetings in April 2015 in Japan, and are publicly available online.

AirSWOT flights and field campaigns for the 2017 Arctic-Boreal Vulnerability Experiment (ABoVE)

NASA Astrophysics Data System (ADS)

Smith, L. C.; Pavelsky, T.; Lettenmaier, D. P.; Gleason, C. J.; Pietroniro, A.; Applejohn, A.; Arvesen, J. C.; Bjella, K.; Carter, T.; Chao, R.; Cooley, S. W.; Cooper, M. G.; Cretaux, J. F.; Douglass, T.; Faria, D.; Fayne, J.; Fiset, J. M.; Goodman, S.; Hanna, B.; Harlan, M.; Langhorst, T.; Marsh, P.; Moreira, D. M.; Minear, J. T.; Onclin, C.; Overstreet, B. T.; Peters, D.; Pettit, J.; Pitcher, L. H.; Russell, M.; Spence, C.; Topp, S.; Turner, K. W.; Vimal, S.; Wilcox, E.; Woodward, J.; Yang, D.; Zaino, A.

2017-12-01

Some 50% of Canada and 80% of Alaska is thought to be underlain by permafrost, influencing the hydrology, ecology and carbon cycles of Arctic-Boreal landscapes. This influence includes enhanced presence of millions of lakes and wetlands, which release trace gases while supporting critical ecosystems and traditional subsistence economies. Permafrost is challenging to infer from remote sensing and difficult to sample in the field. A series of 2017 AirSWOT flights flown for the NASA Arctic-Boreal Vulnerability Experiment (ABoVE) will study whether small variations in water surface elevations (WSEs) of Arctic-Boreal lakes are sensitive to presence and/or disturbance of permafrost. AirSWOT is an experimental NASA airborne radar designed to map WSE and a precursor to SWOT, a forthcoming NASA/CNES/CSA satellite mission to map WSE globally with launch in 2021. The ABoVE AirSWOT flight experiments adopted long flight lines of the broader ABoVE effort to traverse broad spatial gradients of permafrost, climate, ecology, and geology. AirSWOT acquisitions consisted of long (1000s of kilometers) strips of Ka-band interferometric radar imagery, and high resolution visible/NIR imagery and DEMs from a digital Cirrus CIR camera. Intensive AirSWOT mapping and ground-based GPS field surveys were conducted at 11 field sites for eight study areas of Canada and Alaska: 1) Saint-Denis, Redberry Lake, North Saskatchewan River (Saskatchewan); 2) Peace-Athabasca Delta (Alberta); 3) Slave River Delta (N.W.T.); 4) Canadian Shield (Yellowknife area, Daring Lake, N.W.T.); 5) Mackenzie River (Inuvik-Tuktoyaktuk corridor, N.W.T.); 6) Old Crow Flats (Yukon Territory); 7) Sagavanirktok River (Alaska); 8) Yukon Flats (Alaska). Extensive ground campaigns were conducted by U.S. and Canadian collaborators to collect high quality surveys of lake WSE, river WSE and discharge, and shoreline locations. Field experiments included traditional and novel GPS surveying methods, including custom-built GPS buoys

Arctic tipping points in an Earth system perspective.

PubMed

Wassmann, Paul; Lenton, Timothy M

2012-02-01

We provide an introduction to the volume The Arctic in the Earth System perspective: the role of tipping points. The terms tipping point and tipping element are described and their role in current science, general debates, and the Arctic are elucidated. From a wider perspective, the volume focuses upon the role of humans in the Arctic component of the Earth system and in particular the envelope for human existence, the Arctic ecosystems. The Arctic climate tipping elements, the tipping elements in Arctic ecosystems and societies, and the challenges of governance and anticipation are illuminated through short summaries of eight publications that derive from the Arctic Frontiers conference in 2011 and the EU FP7 project Arctic Tipping Points. Then some ideas based upon resilience thinking are developed to show how wise system management could ease pressures on Arctic systems in order to keep them away from tipping points.

The Arctic Report Card: Communicating the State of the Rapidly Changing Arctic to a Diverse Audience via the Worldwide Web

NASA Astrophysics Data System (ADS)

Jeffries, M. O.; Richter-Menge, J.; Overland, J. E.; Soreide, N. N.

2013-12-01

Rapid change is occurring throughout the Arctic environmental system. The goal of the Arctic Report Card is to communicate the nature of the many changes to a diverse audience via the Worldwide Web. First published in 2006, the Arctic Report Card is a peer-reviewed publication containing clear, reliable and concise scientific information on the current state of the Arctic environment relative to observational records. Available only online, it is intended to be an authoritative source for scientists, teachers, students, decision-makers, policy-makers and the general public interested in the Arctic environment and science. The Arctic Report Card is organized into five sections: Atmosphere; Sea Ice & Ocean; Marine Ecosystem; Terrestrial Ecosystem; Terrestrial Cryosphere. Arctic Report Card 2012, the sixth annual update, comprised 20 essays on physical and biological topics prepared by an international team of 141 scientists from 15 different countries. For those who want a quick summary, the Arctic Report Card home page provides highlights of key events and findings, and a short video that is also available on YouTube. The release of the Report Card each autumn is preceded by a NOAA press release followed by a press conference, when the Web site is made public. The release of Arctic Report Card 2012 at an AGU Fall Meeting press conference on 5 December 2012 was subsequently reported by leading media organizations. The NOAA Arctic Web site, of which the Report Card is a part, is consistently at the top of Google search results for the keyword 'arctic', and the Arctic Report Card Web site tops search results for keyword "arctic report" - pragmatic indications of a Web site's importance and popularity. As another indication of the Web site's impact, in December 2012, the month when the 2012 update was released, the Arctic Report Card Web site was accessed by 19,851 unique sites in 105 countries, and 4765 Web site URLs referred to the Arctic Report Card. The 2012 Arctic

Detecting and Understanding Changing Arctic Carbon Emissions

NASA Astrophysics Data System (ADS)

Bruhwiler, L.

2017-12-01

Warming in the Arctic has proceeded faster than anyplace on Earth. Our current understanding of biogeochemistry suggests that we can expect feedbacks between climate and carbon in the Arctic. Changes in terrestrial fluxes of carbon can be expected as the Arctic warms, and the vast stores of organic carbon frozen in Arctic soils could be mobilized to the atmosphere, with possible significant impacts on global climate. Quantifying trends in Arctic carbon exchanges is important for policymaking because greater reductions in anthropogenic emissions may be required to meet climate goals. Observations of greenhouse gases in the Arctic and globally have been collected for several decades. Analysis of this data does not currently support significantly changed Arctic emissions of CH4, however it is difficult to detect changes in Arctic emissions because of transport from lower latitudes and large inter-annual variability. Unfortunately, current space-based remote sensing systems have limitations at Arctic latitudes. Modeling systems can help untangle the Arctic budget of greenhouse gases, but they are dependent on underlying prior fluxes, wetland distributions and global anthropogenic emissions. Also, atmospheric transport models may have significant biases and errors. For example, unrealistic near-surface stability can lead to underestimation of emissions in atmospheric inversions. We discuss our current understanding of the Arctic carbon budget from both top-down and bottom-up approaches. We show that current atmospheric inversions agree well on the CH4 budget. On the other hand, bottom-up models vary widely in their predictions of natural emissions, with some models predicting emissions too large to be accommodated by the budget implied by global observations. Large emissions from the shallow Arctic ocean are also inconsistent with atmospheric observations. We also discuss the sensitivity of the current atmospheric network to what is likely small, gradual increases in

The Circumpolar Arctic vegetation map

USGS Publications Warehouse

Walker, Donald A.; Raynolds, Martha K.; Daniels, F.J.A.; Einarsson, E.; Elvebakk, A.; Gould, W.A.; Katenin, A.E.; Kholod, S.S.; Markon, C.J.; Melnikov, E.S.; Moskalenko, N.G.; Talbot, S. S.; Yurtsev, B.A.; Bliss, L.C.; Edlund, S.A.; Zoltai, S.C.; Wilhelm, M.; Bay, C.; Gudjonsson, G.; Ananjeva, G.V.; Drozdov, D.S.; Konchenko, L.A.; Korostelev, Y.V.; Ponomareva, O.E.; Matveyeva, N.V.; Safranova, I.N.; Shelkunova, R.; Polezhaev, A.N.; Johansen, B.E.; Maier, H.A.; Murray, D.F.; Fleming, Michael D.; Trahan, N.G.; Charron, T.M.; Lauritzen, S.M.; Vairin, B.A.

2005-01-01

Question: What are the major vegetation units in the Arctic, what is their composition, and how are they distributed among major bioclimate subzones and countries? Location: The Arctic tundra region, north of the tree line. Methods: A photo-interpretive approach was used to delineate the vegetation onto an Advanced Very High Resolution Radiometer (AVHRR) base image. Mapping experts within nine Arctic regions prepared draft maps using geographic information technology (ArcInfo) of their portion of the Arctic, and these were later synthesized to make the final map. Area analysis of the map was done according to bioclimate subzones, and country. The integrated mapping procedures resulted in other maps of vegetation, topography, soils, landscapes, lake cover, substrate pH, and above-ground biomass. Results: The final map was published at 1:7 500 000 scale map. Within the Arctic (total area = 7.11 x 106 km 2), about 5.05 ?? 106 km2 is vegetated. The remainder is ice covered. The map legend generally portrays the zonal vegetation within each map polygon. About 26% of the vegetated area is erect shrublands, 18% peaty graminoid tundras, 13% mountain complexes, 12% barrens, 11% mineral graminoid tundras, 11% prostrate-shrub tundras, and 7% wetlands. Canada has by far the most terrain in the High Arctic mostly associated with abundant barren types and prostrate dwarf-shrub tundra, whereas Russia has the largest area in the Low Arctic, predominantly low-shrub tundra. Conclusions: The CAVM is the first vegetation map of an entire global biome at a comparable resolution. The consistent treatment of the vegetation across the circumpolar Arctic, abundant ancillary material, and digital database should promote the application to numerous land-use, and climate-change applications and will make updating the map relatively easy. ?? IAVS; Opulus Press.

Identifying Priorities for International Arctic Research and Policy

NASA Astrophysics Data System (ADS)

Rachold, V.; Hik, D.; Barr, S.

2015-12-01

The International Arctic Science Committee (IASC) is a non-governmental, international scientific organization, founded in 1990 by representatives of national scientific organizations of the eight Arctic countries - Canada, Denmark, Finland, Iceland, Norway, Russia (at that time Union of Soviet Socialist Republics), Sweden and the United States of America. Over the past 25 years, IASC has evolved into the leading international science organization of the North and its membership today includes 23 countries involved in all aspects of Arctic research, including 15 non-Arctic countries (Austria, China, the Czech Republic, France, Germany, India, Italy, Japan, the Netherlands, Poland, Portugal, South Korea, Spain, Switzerland and the UK). The Founding Articles committed IASC to pursue a mission of encouraging and facilitating cooperation in all aspects of Arctic research, in all countries engaged in Arctic research and in all areas of the Arctic region. IASC promotes and supports leading-edge multi-disciplinary research in order to foster a greater scientific understanding of the Arctic region and its role in the Earth system. IASC has organized three forward-looking conferences focused on international and interdisciplinary perspectives for advancing Arctic research cooperation and applications of Arctic knowledge. Indeed, the IASC Founding Articles call for IASC to host these conferences periodically in order to "review the status of Arctic science, provide scientific and technical advice, and promote cooperation and links with other national and international organizations." Through its members, including national science organizations and funding agencies from all countries engaged in Arctic research, IASC is uniquely placed to undertake this task. As an accredited observer on the Arctic Council, IASC is also in the position to introduce the outcome of its science planning efforts into the Arctićs main political body and to liaise with the Arctic Council Permanent

Circumpolar Arctic vegetation mapping workshop

USGS Publications Warehouse

Walker, D. A.; Markon, C.J.

1996-01-01

The first Circumpolar Arctic Vegetation Mapping Workshop was held in the historic village of Lakta on the outskirts of St. Petersburg, Russia, March 21-25, 1994. The primary goals of the workshop were to: (1) review the status of arctic vegetation mapping in the circumpolar countries and (2) develop a strategy for synthesizing and updating the existing information into a new series of maps that portray the current state of knowledge. Such products are important for a number of purposes, such as the international effort to understand the consequences of global change in Arctic regions, to predict the direction of future changes, and for informed planning of resource development in the Arctic.

Role of Greenland meltwater in the changing Arctic

NASA Astrophysics Data System (ADS)

Dukhovskoy, Dmitry; Proshutinsky, Andrey; Timmermans, Mary-Louise; Myers, Paul; Platov, Gennady; Bamber, Jonathan; Curry, Beth; Somavilla, Raquel

2016-04-01

Observational data show that the Arctic ocean-ice-atmosphere system has been changing over the last two decades. Arctic change is manifest in the atypical behavior of the climate indices in the 21st century. Before the 2000s, these indices characterized the quasi-decadal variability of the Arctic climate related to different circulation regimes. Between 1948 and 1996, the Arctic atmospheric circulation alternated between anticyclonic circulation regimes and cyclonic circulation regimes with a period of 10-15 years. Since 1997, however, the Arctic has been dominated by an anticyclonic regime. Previous studies indicate that in the 20th century, freshwater and heat exchange between the Arctic Ocean and the sub-Arctic seas were self-regulated and their interactions were realized via quasi-decadal climate oscillations. What physical processes in the Arctic Ocean - sub-Arctic ocean-ice-atmosphere system are responsible for the observed changes in Arctic climate variability? The presented work is motivated by our hypothesis that in the 21st century, these quasi-decadal oscillations have been interrupted as a result of an additional freshwater source associated with Greenland Ice Sheet melt. Accelerating since the early 1990s, the Greenland Ice Sheet mass loss exerts a significant impact on thermohaline processes in the sub-Arctic seas. Surplus Greenland freshwater, the amount of which is about a third of the freshwater volume fluxed into the region during the 1970s Great Salinity Anomaly event, can spread and accumulate in the sub-Arctic seas influencing convective processes there. It is not clear, however, whether Greenland freshwater can propagate into the interior convective regions in the Labrador Sea and the Nordic Seas. In order to investigate the fate and pathways of Greenland freshwater in the sub-Arctic seas and to determine how and at what rate Greenland freshwater propagates into the convective regions, several numerical experiments using a passive tracer to

Behavioral interactions of penned red and arctic foxes

USGS Publications Warehouse

Rudzinski, D.R.; Graves, H.B.; Sargeant, A.B.; Storm, G.L.

1982-01-01

Expansion of the geographical distribution of red foxes (Vulpes vulpes) into the far north tundra region may lead to competition between arctic (Alopex lagopus) and red foxes for space and resources. Behavioral interactions between red and arctic foxes were evaluated during 9 trials conducted in a 4.05-ha enclosure near Woodworth, North Dakota. Each trial consisted of introducing a male-female pair of arctic foxes into the enclosure and allowing them to acclimate for approximately a week before releasing a female red fox into the enclosure, followed by her mate a few days later. In 8 of 9 trials, red foxes were dominant over arctic foxes during encounters. Activity of the arctic foxes decreased upon addition of red foxes. Arctic foxes tried unsuccessfully to defend preferred den, resting, and feeding areas. Even though the outcome of competition between red and arctic foxes in the Arctic is uncertain, the more aggressive red fox can dominate arctic foxes in direct competition for den sites and other limited resources.

Global warming and effects on the Arctic fox.

PubMed

Fuglei, Eva; Ims, Rolf Anker

2008-01-01

We predict the effect of global warming on the arctic fox, the only endemic terrestrial predatory mammals in the arctic region. We emphasize the difference between coastal and inland arctic fox populations. Inland foxes rely on peak abundance of lemming prey to sustain viable populations. In the short-term, warmer winters result in missed lemming peak years and reduced opportunities for successful arctic fox breeding. In the long-term, however, warmer climate will increase plant productivity and more herbivore prey for competitive dominant predators moving in from the south. The red fox has already intruded the arctic region and caused a retreat of the southern limit of arctic fox distribution range. Coastal arctic foxes, which rely on the richer and temporally stable marine subsidies, will be less prone to climate-induced resource limitations. Indeed, arctic islands, becoming protected from southern species invasions as the extent of sea ice is decreasing, may become the last refuges for coastal populations of Arctic foxes.

Arctic Synthesis Collaboratory: A Virtual Organization for Transformative Research and Education on a Changing Arctic

NASA Astrophysics Data System (ADS)

Warnick, W. K.; Wiggins, H. V.; Hinzman, L.; Holland, M.; Murray, M. S.; Vörösmarty, C.; Loring, A. J.

2008-12-01

About the Arctic Synthesis Collaboratory The Arctic Synthesis Collaboratory concept, developed through a series of NSF-funded workshops and town hall meetings, is envisioned as a cyber-enabled, technical, organizational, and social-synthesis framework to foster: • Interactions among interdisciplinary experts and stakeholders • Integrated data analysis and modeling activities • Training and development of the arctic science community • Delivery of outreach, education, and policy-relevant resources Scientific Rationale The rapid rate of arctic change and our incomplete understanding of the arctic system present the arctic community with a grand scientific challenge and three related issues. First, a wealth of observations now exists as disconnected data holdings, which must be coordinated and synthesized to fully detect and assess arctic change. Second, despite great strides in the development of arctic system simulations, we still have incomplete capabilities for modeling and predicting the behavior of the system as a whole. Third, policy-makers, stakeholders, and the public are increasingly making demands of the science community for forecasts and guidance in mitigation and adaptation strategies. Collaboratory Components The Arctic Synthesis Collaboratory is organized around four integrated functions that will be established virtually as a distributed set of activities, but also with the advantage of existing facilities that could sponsor some of the identified activities. Community Network "Meeting Grounds:" The Collaboratory will link distributed individuals, organizations, and activities to enable collaboration and foster new research initiatives. Specific activities could include: an expert directory, social networking services, and virtual and face-to-face meetings. Data Integration, Synthesis, and Modeling Activities: The Collaboratory will utilize appropriate tools to enable the combination of data and models. Specific activities could include: a web

NASA's Earth Venture-1 (EV-1) Airborne Science Investigations

NASA Technical Reports Server (NTRS)

Guillory, A.; Denkins, T.; Allen, B. Danette; Braun, Scott A.; Crawford, James H.; Jensen, Eric J.; Miller, Charles E.; Moghaddam, Mahta; Maring, Hal

2011-01-01

In 2010, NASA announced the first Earth Venture (EV-1) selections in response to a recommendation made by the National Research Council for low-cost investigations fostering innovation in Earth science. The five EV-1 investigations span the Earth science focus areas of atmosphere, weather, climate, water and energy and, carbon and represent earth science researchers from NASA as well as other government agencies, academia and industry from around the world. The EV-1 missions are: 1) Airborne Microwave Observatory of Subcanopy and Subsurface (AirMOSS), 2) Airborne Tropical Tropopause Experiment (ATTREX), 3) Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE), 4) Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ), and 5) Hurricane And Severe Storm Sentinel (HS3). The Earth Venture missions are managed out of the Earth System Science Pathfinder (ESSP) Program Office (Allen, et. al. 2010b)

Challenges of climate change: an Arctic perspective.

PubMed

Corell, Robert W

2006-06-01

Climate change is being experienced particularly intensely in the Arctic. Arctic average temperature has risen at almost twice the rate as that of the rest of the world in the past few decades. Widespread melting of glaciers and sea ice and rising permafrost temperatures present additional evidence of strong Arctic warming. These changes in the Arctic provide an early indication of the environmental and societal significance of global consequences. The Arctic also provides important natural resources to the rest of the world (such as oil, gas, and fish) that will be affected by climate change, and the melting of Arctic glaciers is one of the factors contributing to sea level rise around the globe. An acceleration of these climatic trends is projected to occur during this century, due to ongoing increases in concentrations of greenhouse gases in the Earth's atmosphere. These Arctic changes will, in turn, impact the planet as a whole.

Spatial distribution of aquatic marine fungi across the western Arctic and sub-arctic.

PubMed

Hassett, Brandon T; Ducluzeau, Anne-Lise L; Collins, Roy E; Gradinger, Rolf

2017-02-01

Fungi are important parasites of primary producers and nutrient cyclers in aquatic ecosystems. In the Pacific-Arctic domain, fungal parasitism is linked to light intensities and algal stress that can elevate disease incidence on algae and reduce diatom concentrations. Fungi are vastly understudied in the marine realm and knowledge of their function is constrained by the current understanding of fungal distribution and drivers on global scales. To investigate the spatial distribution of fungi in the western Arctic and sub-Arctic, we used high throughput methods to sequence 18S rRNA, cloned and sequenced 28S rRNA and microscopically counted chytrid-infected diatoms. We identified a broad distribution of fungal taxa predominated by Chytridiomycota and Dikarya. Phylogenetic analysis of our Chytridiomycota clones placed Arctic marine fungi sister to the order Lobulomycetales. This clade of fungi predominated in fungal communities under ice with low snowpack. Microscopic examination of fixed seawater and sea ice samples revealed chytrids parasitizing diatoms collected across the Arctic that notably infected 25% of a single diatom species in the Bering Sea. The Pezizomycotina comprised > 95% of eukaryotic sequence reads in Greenland, providing preliminary evidence for osmotrophs being a substitute for algae as the base of food webs. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

Arctic Logistics Information and Support: ALIAS

NASA Astrophysics Data System (ADS)

Warnick, W. K.

2004-12-01

The ALIAS web site is a gateway to logistics information for arctic research, funded by the U.S. National Science Foundation, and created and maintained by the Arctic Research Consortium of the United States (ARCUS). ALIAS supports the collaborative development and efficient use of all arctic logistics resources. It presents information from a searchable database, including both arctic terrestrial resources and arctic-capable research vessels, on a circumpolar scale. With this encompassing scope, ALIAS is uniquely valuable as a tool to promote and facilitate international collaboration between researchers, which is of increasing importance for vessel-based research due to the high cost and limited number of platforms. Users of the web site can identify vessels which are potential platforms for their research, examine and compare vessel specifications and facilities, learn about research cruises the vessel has performed in the past, and find contact information for scientists who have used the vessel, as well as for the owners and operators of the vessel. The purpose of this poster presentation is to inform the scientific community about the ALIAS website as a tool for planning arctic research generally, and particularly for identifying and contacting vessels which may be suitable for planned ship-based research projects in arctic seas.

Arctic Messages: Arctic Research in the Vocabulary of Poets and Artists

NASA Astrophysics Data System (ADS)

Samsel, F.

2017-12-01

Arctic Messages is a series of prints created by a multidisciplinary team designed to build understanding and encourage dialogue about the changing Arctic ecosystems and the impacts on global weather patterns. Our team comprised of Arctic researchers, a poet, a visual artist, photographers and visualization experts set out to blend the vocabularies of our disciplines in order to provide entry into the content for diverse audiences. Arctic Messages is one facet of our broader efforts experimenting with mediums of communication able to provide entry to those of us outside scientific of fields. We believe that the scientific understanding of change presented through the languages art will speak to our humanity as well as our intellect. The prints combine poetry, painting, visualization, and photographs, drawn from the Arctic field studies of the Next Generation Ecosystem Experiments research team at Los Alamos National Laboratory. The artistic team interviewed the scientists, read their papers and poured over their field blogs. The content and concepts are designed to portray the wonder of nature, the complexity of the science and the dedication of the researchers. Smith brings to life the intertwined connection between the research efforts, the ecosystems and the scientist's experience. Breathtaking photography of the research site is accompanied by Samsel's drawings and paintings of the ecosystem relationships and geological formations. Together they provide entry to the variety and wonder of life on the Arctic tundra and that resting quietly in the permafrost below. Our team has experimented with many means of presentation from complex interactive systems to quiet individual works. Here we are presenting a series of prints, each one based on a single thread of the research or the scientist's experience but containing intertwined relationships similar to the ecosystems they represent. Earlier interactive systems, while engaging, were not tuned to those seeking

Collaborative Research: Improving Decadal Prediction of Arctic Climate Variability and Change Using a Regional Arctic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gutowski, William J.

This project developed and applied a regional Arctic System model for enhanced decadal predictions. It built on successful research by four of the current PIs with support from the DOE Climate Change Prediction Program, which has resulted in the development of a fully coupled Regional Arctic Climate Model (RACM) consisting of atmosphere, land-hydrology, ocean and sea ice components. An expanded RACM, a Regional Arctic System Model (RASM), has been set up to include ice sheets, ice caps, mountain glaciers, and dynamic vegetation to allow investigation of coupled physical processes responsible for decadal-scale climate change and variability in the Arctic. RASMmore » can have high spatial resolution (~4-20 times higher than currently practical in global models) to advance modeling of critical processes and determine the need for their explicit representation in Global Earth System Models (GESMs). The pan-Arctic region is a key indicator of the state of global climate through polar amplification. However, a system-level understanding of critical arctic processes and feedbacks needs further development. Rapid climate change has occurred in a number of Arctic System components during the past few decades, including retreat of the perennial sea ice cover, increased surface melting of the Greenland ice sheet, acceleration and thinning of outlet glaciers, reduced snow cover, thawing permafrost, and shifts in vegetation. Such changes could have significant ramifications for global sea level, the ocean thermohaline circulation and heat budget, ecosystems, native communities, natural resource exploration, and commercial transportation. The overarching goal of the RASM project has been to advance understanding of past and present states of arctic climate and to improve seasonal to decadal predictions. To do this the project has focused on variability and long-term change of energy and freshwater flows through the arctic climate system. The three foci of this research are

Sea Ice Pressure Ridge Height Distributions for the Arctic Ocean in Winter, Just Prior to Melt

NASA Astrophysics Data System (ADS)

Duncan, K.; Farrell, S. L.; Richter-Menge, J.; Hutchings, J.; Dominguez, R.; Connor, L. N.

2016-12-01

Pressure ridges are one of the most dominant morphological features of the Arctic sea ice pack. An impediment to navigation, pressure ridges are also of climatological interest since they impact the mass, energy and momentum transfer budgets for the Arctic Ocean. Understanding the regional and seasonal distributions of ridge sail heights, and their variability, is important for quantifying total sea ice mass, and for improved treatment of sea ice dynamics in high-resolution numerical models. Observations of sail heights from airborne and ship-based platforms have been documented in previous studies, however studies with both high spatial and temporal resolution, across multiple regions of the Arctic, are only recently possible with the advent of dedicated airborne surveys of the Arctic Ocean. In this study we present results from the high-resolution Digital Mapping System (DMS), flown as part of NASA's Operation IceBridge missions. We use DMS imagery to calculate ridge sail heights, derived from the shadows they cast combined with the solar elevation angle and the known pixel size of each image. Our analyses describe sea ice conditions at the end of winter, during the months of March and April, over a period spanning seven years, from 2010 to 2016. The high spatial resolution (0.1m) and temporal extent (seven years) of the DMS data set provides, for the first time, the full sail-height distributions of both first-year and multi-year sea ice. We present the inter-annual variability in sail height distributions for both the Central Arctic and the Beaufort and Chukchi Seas. We validate our results via comparison with spatially coincident high-resolution SAR imagery and airborne laser altimeter elevations.

Arctic summer school onboard an icebreaker

NASA Astrophysics Data System (ADS)

Alexeev, Vladimir A.; Repina, Irina A.

2014-05-01

The International Arctic Research Center (IARC) of the University of Alaska Fairbanks conducted a summer school for PhD students, post-docs and early career scientists in August-September 2013, jointly with an arctic expedition as a part of NABOS project (Nansen and Amundsen Basin Observational System) onboard the Russian research vessel "Akademik Fedorov". Both the summer school and NABOS expedition were funded by the National Science Foundation. The one-month long summer school brought together graduate students and young scientists with specialists in arctic oceanography and climate to convey to a new generation of scientists the opportunities and challenges of arctic climate observations and modeling. Young scientists gained hands-on experience during the field campaign and learned about key issues in arctic climate from observational, diagnostic, and modeling perspectives. The summer school consisted of background lectures, participation in fieldwork and mini-projects. The mini-projects were performed in collaboration with summer school instructors and members of the expedition. Key topics covered in the lectures included: - arctic climate: key characteristics and processes; - physical processes in the Arctic Ocean; - sea ice and the Arctic Ocean; - trace gases, aerosols, and chemistry: importance for climate changes; - feedbacks in the arctic system (e.g., surface albedo, clouds, water vapor, circulation); - arctic climate variations: past, ongoing, and projected; - global climate models: an overview. An outreach specialist from the Miami Science Museum was writing a blog from the icebreaker with some very impressive statistics (results as of January 1, 2014): Total number of blog posts: 176 Blog posts written/contributed by scientists: 42 Blog views: 22,684 Comments: 1,215 Number of countries who viewed the blog: 89 (on 6 continents) The 33-day long NABOS expedition started on August 22, 2013 from Kirkenes, Norway. The vessel ("Akademik Fedorov") returned to

Advancing NOAA NWS Arctic Program Development

NASA Astrophysics Data System (ADS)

Timofeyeva-Livezey, M. M.; Horsfall, F. M. C.; Meyers, J. C.; Churma, M.; Thoman, R.

2016-12-01

Environmental changes in the Arctic require changes in the way the National Oceanic and Atmospheric Administration (NOAA) delivers hydrological and meteorological information to prepare the region's societies and indigenous population for emerging challenges. These challenges include changing weather patterns, changes in the timing and extent of sea ice, accelerated soil erosion due to permafrost decline, increasing coastal vulnerably, and changes in the traditional food supply. The decline in Arctic sea ice is opening new opportunities for exploitation of natural resources, commerce, tourism, and military interest. These societal challenges and economic opportunities call for a NOAA integrated approach for delivery of environmental information including climate, water, and weather data, forecasts, and warnings. Presently the NOAA Arctic Task Force provides leadership in programmatic coordination across NOAA line offices. National Weather Service (NWS) Alaska Region and the National Centers for Environmental Prediction (NCEP) provide the foundational operational hydro-meteorological products and services in the Arctic. Starting in 2016, NOAA's NWS will work toward improving its role in programmatic coordination and development through assembling an NWS Arctic Task Team. The team will foster ties in the Arctic between the 11 NWS national service programs in climate, water, and weather information, as well as between Arctic programs in NWS and other NOAA line offices and external partners. One of the team outcomes is improving decision support tools for the Arctic. The Local Climate Analysis Tool (LCAT) currently has more than 1100 registered users, including NOAA staff and technical partners. The tool has been available online since 2013 (http://nws.weather.gov/lcat/ ). The tool links trusted, recommended NOAA data and analytical capabilities to assess impacts of climate variability and climate change at local levels. A new capability currently being developed will

Variability and Trends in the Arctic Sea Ice Cover: Results from Different Techniques

NASA Technical Reports Server (NTRS)

Comiso, Josefino C.; Meier, Walter N.; Gersten, Robert

2017-01-01

Variability and trend studies of sea ice in the Arctic have been conducted using products derived from the same raw passive microwave data but by different groups using different algorithms. This study provides consistency assessment of four of the leading products, namely, Goddard Bootstrap (SB2), Goddard NASA Team (NT1), EUMETSAT Ocean and Sea Ice Satellite Application Facility (OSI-SAF 1.2), and Hadley HadISST 2.2 data in evaluating variability and trends in the Arctic sea ice cover. All four provide generally similar ice patterns but significant disagreements in ice concentration distributions especially in the marginal ice zone and adjacent regions in winter and meltponded areas in summer. The discrepancies are primarily due to different ways the four techniques account for occurrences of new ice and meltponding. However, results show that the different products generally provide consistent and similar representation of the state of the Arctic sea ice cover. Hadley and NT1 data usually provide the highest and lowest monthly ice extents, respectively. The Hadley data also show the lowest trends in ice extent and ice area at negative 3.88 percent decade and negative 4.37 percent decade, respectively, compared to an average of negative 4.36 percent decade and negative 4.57 percent decade for all four. Trend maps also show similar spatial distribution for all four with the largest negative trends occurring at the Kara/Barents Sea and Beaufort Sea regions, where sea ice has been retreating the fastest. The good agreement of the trends especially with updated data provides strong confidence in the quantification of the rate of decline in the Arctic sea ice cover.

In Brief: Arctic Report Card

NASA Astrophysics Data System (ADS)

Showstack, Randy

2009-11-01

The 2009 annual update of the Arctic Report Card, issued on 22 October, indicates that “warming of the Arctic continues to be widespread, and in some cases dramatic. Linkages between air, land, sea, and biology are evident.” The report, a collaborative effort of 71 national and international scientists initiated in 2006 by the Climate Program Office of the U.S. National Oceanic and Atmospheric Administration (NOAA), highlights several concerns, including a change in large-scale wind patterns affected by the loss of summer sea ice; the replacement of multiyear sea ice by first-year sea ice; warmer and fresher water in the upper ocean linked to new ice-free areas; and the effects of the loss of sea ice on Arctic plant, animal, and fish species. “Climate change is happening faster in the Arctic than any other place on Earth-and with wide-ranging consequences,” said NOAA administrator Jane Lubchenco. “This year“s Arctic Report Card underscores the urgency of reducing greenhouse gas pollution and adapting to climate changes already under way.”

Variability in Arctic sea ice topography and atmospheric form drag: Combining IceBridge laser altimetry with ASCAT radar backscatter.

NASA Astrophysics Data System (ADS)

Petty, A.; Tsamados, M.; Kurtz, N. T.

2016-12-01

Here we present atmospheric form drag estimates over Arctic sea ice using high resolution, three-dimensional surface elevation data from NASA's Operation IceBridge Airborne Topographic Mapper (ATM), and surface roughness estimates from the Advanced Scatterometer (ASCAT). Surface features of the ice pack (e.g. pressure ridges) are detected using IceBridge ATM elevation data and a novel surface feature-picking algorithm. We use simple form drag parameterizations to convert the observed height and spacing of surface features into an effective atmospheric form drag coefficient. The results demonstrate strong regional variability in the atmospheric form drag coefficient, linked to variability in both the height and spacing of surface features. This includes form drag estimates around 2-3 times higher over the multiyear ice north of Greenland, compared to the first-year ice of the Beaufort/Chukchi seas. We compare results from both scanning and linear profiling to ensure our results are consistent with previous studies investigating form drag over Arctic sea ice. A strong correlation between ASCAT surface roughness estimates (using radar backscatter) and the IceBridge form drag results enable us to extrapolate the IceBridge data collected over the western-Arctic across the entire Arctic Ocean. While our focus is on spring, due to the timing of the primary IceBridge campaigns since 2009, we also take advantage of the autumn data collected by IceBridge in 2015 to investigate seasonality in Arctic ice topography and the resulting form drag coefficient. Our results offer the first large-scale assessment of atmospheric form drag over Arctic sea ice due to variable ice topography (i.e. within the Arctic pack ice). The analysis is being extended to the Antarctic IceBridge sea ice data, and the results are being used to calibrate a sophisticated form drag parameterization scheme included in the sea ice model CICE, to improve the representation of form drag over Arctic and

The Arctic Research Consortium of the United States

NASA Astrophysics Data System (ADS)

Warnick, W. K.; Wiggins, H. V.

2007-12-01

The Arctic Research Consortium of the United States (ARCUS) is a nonprofit membership organization composed of universities and institutions that have a substantial commitment to research in the Arctic. ARCUS was formed in 1988 to serve as a forum for planning, facilitating, coordinating, and implementing interdisciplinary studies of the Arctic; to act as a synthesizer and disseminator of scientific information on arctic research; and to educate scientists and the general public about the needs and opportunities for research in the Arctic. ARCUS, in collaboration with the broad science community, relevant agencies and organizations, and other stakeholders, coordinates science planning and educational activities across disciplinary and organizational boundaries. Examples of current ARCUS science planning activities include: serving as the project office for the multi-agency Study of Environmental Arctic Change (SEARCH) program and providing support to the related Bering Ecosystem Study (BEST), and serving as the Science Management Office for the National Science Foundation (NSF) Arctic System Science (ARCSS) Program. ARCUS' central educational activity is PolarTREC (Teachers and Researchers Exploring and Collaborating), an International Polar Year (IPY) program whereby K-12 educators and researchers work together in hands-on field experiences in the Arctic and Antarctic to advance polar science education. Additional science planning, educational, information, and outreach activities include the Witness the Arctic newsletter, the Arctic Visiting Speakers' Series, the ArcticInfo listserve, the Internet Media Archive (IMA), the annual Arctic Forum conference, and many others. More information about these and other ARCUS activities can be found at the ARCUS website at www.arcus.org.

Chapter 3: Circum-Arctic mapping project: New magnetic and gravity anomaly maps of the Arctic

USGS Publications Warehouse

Gaina, C.; Werner, S.C.; Saltus, R.; Maus, S.; Aaro, S.; Damaske, D.; Forsberg, R.; Glebovsky, V.; Johnson, Kevin; Jonberger, J.; Koren, T.; Korhonen, J.; Litvinova, T.; Oakey, G.; Olesen, O.; Petrov, O.; Pilkington, M.; Rasmussen, T.; Schreckenberger, B.; Smelror, M.

2011-01-01

New Circum-Arctic maps of magnetic and gravity anomalies have been produced by merging regional gridded data. Satellite magnetic and gravity data were used for quality control of the long wavelengths of the new compilations. The new Circum-Arctic digital compilations of magnetic, gravity and some of their derivatives have been analyzed together with other freely available regional and global data and models in order to provide a consistent view of the tectonically complex Arctic basins and surrounding continents. Sharp, linear contrasts between deeply buried basement blocks with different magnetic properties and densities that can be identified on these maps can be used, together with other geological and geophysical information, to refine the tectonic boundaries of the Arctic domain. ?? 2011 The Geological Society of London.

Arctic Boreal Vulnerability Experiment (ABoVE) Science Cloud

NASA Astrophysics Data System (ADS)

Duffy, D.; Schnase, J. L.; McInerney, M.; Webster, W. P.; Sinno, S.; Thompson, J. H.; Griffith, P. C.; Hoy, E.; Carroll, M.

2014-12-01

The effects of climate change are being revealed at alarming rates in the Arctic and Boreal regions of the planet. NASA's Terrestrial Ecology Program has launched a major field campaign to study these effects over the next 5 to 8 years. The Arctic Boreal Vulnerability Experiment (ABoVE) will challenge scientists to take measurements in the field, study remote observations, and even run models to better understand the impacts of a rapidly changing climate for areas of Alaska and western Canada. The NASA Center for Climate Simulation (NCCS) at the Goddard Space Flight Center (GSFC) has partnered with the Terrestrial Ecology Program to create a science cloud designed for this field campaign - the ABoVE Science Cloud. The cloud combines traditional high performance computing with emerging technologies to create an environment specifically designed for large-scale climate analytics. The ABoVE Science Cloud utilizes (1) virtualized high-speed InfiniBand networks, (2) a combination of high-performance file systems and object storage, and (3) virtual system environments tailored for data intensive, science applications. At the center of the architecture is a large object storage environment, much like a traditional high-performance file system, that supports data proximal processing using technologies like MapReduce on a Hadoop Distributed File System (HDFS). Surrounding the storage is a cloud of high performance compute resources with many processing cores and large memory coupled to the storage through an InfiniBand network. Virtual systems can be tailored to a specific scientist and provisioned on the compute resources with extremely high-speed network connectivity to the storage and to other virtual systems. In this talk, we will present the architectural components of the science cloud and examples of how it is being used to meet the needs of the ABoVE campaign. In our experience, the science cloud approach significantly lowers the barriers and risks to organizations

Plate tectonic history of the Arctic

NASA Technical Reports Server (NTRS)

Burke, K.

1984-01-01

Tectonic development of the Arctic Ocean is outlined, and geological maps are provided for the Arctic during the mid-Cenozoic, later Cretaceous, late Jurassic, early Cretaceous, early Jurassic and late Devonian. It is concluded that Arctic basin history is moulded by the events of the following intervals: (1) continental collision and immediately subsequent rifting and ocean formation in the Devonian, and continental rifting ocean formation, rapid rotation of microcontinents, and another episode of collision in the latest Jurassic and Cretaceous. It is noted that Cenozoic Arctic basin formation is a smaller scale event superimposed on the late Mesozoic ocean basin.

Public Perceptions of Arctic Change

NASA Astrophysics Data System (ADS)

Hamilton, L.

2014-12-01

What does the general US public know, or think they know, about Arctic change? Two broad nationwide surveys in 2006 and 2010 addressed this topic in general terms, before and after the International Polar Year (IPY). Since then a series of representative national or statewide surveys have carried this research farther. The new surveys employ specific questions that assess public knowledge of basic Arctic facts, along with perceptions about the possible consequences of future Arctic change. Majorities know that late-summer Arctic sea ice area has declined compared with 30 years ago, although substantial minorities -- lately increasing -- believe instead that it has now recovered to historical levels. Majorities also believe that, if the Arctic warms in the future, this will have major effects on the weather where they live. Their expectation of local impacts from far-away changes suggests a degree of global thinking. On the other hand, most respondents do poorly when asked whether melting Arctic sea ice, melting Greenland/Antarctic land ice, or melting Himalayan glaciers could have more effect on sea level. Only 30% knew or guessed the right answer to this question. Similarly, only 33% answered correctly on a simple geography quiz: whether the North Pole could best be described as ice a few feet or yards thick floating over a deep ocean, ice more than a mile thick over land, or a rocky, mountainous landscape. Close analysis of response patterns suggests that people often construct Arctic "knowledge" on items such as sea ice increase/decrease from their more general ideology or worldview, such as their belief (or doubt) that anthropogenic climate change is real. When ideology or worldviews provide no guidance, as on the North Pole or sealevel questions, the proportion of accurate answers is no better than chance. These results show at least casual public awareness and interest in Arctic change, unfortunately not well grounded in knowledge. Knowledge problems seen on

Warm Arctic-cold Siberia: comparing the recent and the early 20th-century Arctic warmings

NASA Astrophysics Data System (ADS)

Wegmann, Martin; Orsolini, Yvan; Zolina, Olga

2018-02-01

The Warm Arctic-cold Siberia surface temperature pattern during recent boreal winter is suggested to be triggered by the ongoing decrease of Arctic autumn sea ice concentration and has been observed together with an increase in mid-latitude extreme events and a meridionalization of tropospheric circulation. However, the exact mechanism behind this dipole temperature pattern is still under debate, since model experiments with reduced sea ice show conflicting results. We use the early twentieth-century Arctic warming (ETCAW) as a case study to investigate the link between September sea ice in the Barents-Kara Sea (BKS) and the Siberian temperature evolution. Analyzing a variety of long-term climate reanalyses, we find that the overall winter temperature and heat flux trend occurs with the reduction of September BKS sea ice. Tropospheric conditions show a strengthened atmospheric blocking over the BKS, strengthening the advection of cold air from the Arctic to central Siberia on its eastern flank, together with a reduction of warm air advection by the westerlies. This setup is valid for both the ETCAW and the current Arctic warming period.

Surveillance of infectious diseases in the Arctic.

PubMed

Bruce, M; Zulz, T; Koch, A

2016-08-01

This study reviews how social and environmental issues affect health in Arctic populations and describes infectious disease surveillance in Arctic Nations with a special focus on the activities of the International Circumpolar Surveillance (ICS) project. We reviewed the literature over the past 2 decades looking at Arctic living conditions and their effects on health and Arctic surveillance for infectious diseases. In regards to other regions worldwide, the Arctic climate and environment are extreme. Arctic and sub-Arctic populations live in markedly different social and physical environments compared to those of their more southern dwelling counterparts. A cold northern climate means people spending more time indoors, amplifying the effects of household crowding, smoking and inadequate ventilation on the person-to-person spread of infectious diseases. The spread of zoonotic infections north as the climate warms, emergence of antibiotic resistance among bacterial pathogens, the re-emergence of tuberculosis, the entrance of HIV into Arctic communities, the specter of pandemic influenza or the sudden emergence and introduction of new viral pathogens pose new challenges to residents, governments and public health authorities of all Arctic countries. ICS is a network of hospitals, public health agencies, and reference laboratories throughout the Arctic working together for the purposes of collecting, comparing and sharing of uniform laboratory and epidemiological data on infectious diseases of concern and assisting in the formulation of prevention and control strategies (Fig. 1). In addition, circumpolar infectious disease research workgroups and sentinel surveillance systems for bacterial and viral pathogens exist. The ICS system is a successful example of collaborative surveillance and research in an extreme environment. Published by Elsevier Ltd.

Trend analysis of Arctic sea ice extent

NASA Astrophysics Data System (ADS)

Silva, M. E.; Barbosa, S. M.; Antunes, Luís; Rocha, Conceição

2009-04-01

The extent of Arctic sea ice is a fundamental parameter of Arctic climate variability. In the context of climate change, the area covered by ice in the Arctic is a particularly useful indicator of recent changes in the Arctic environment. Climate models are in near universal agreement that Arctic sea ice extent will decline through the 21st century as a consequence of global warming and many studies predict a ice free Arctic as soon as 2012. Time series of satellite passive microwave observations allow to assess the temporal changes in the extent of Arctic sea ice. Much of the analysis of the ice extent time series, as in most climate studies from observational data, have been focussed on the computation of deterministic linear trends by ordinary least squares. However, many different processes, including deterministic, unit root and long-range dependent processes can engender trend like features in a time series. Several parametric tests have been developed, mainly in econometrics, to discriminate between stationarity (no trend), deterministic trend and stochastic trends. Here, these tests are applied in the trend analysis of the sea ice extent time series available at National Snow and Ice Data Center. The parametric stationary tests, Augmented Dickey-Fuller (ADF), Phillips-Perron (PP) and the KPSS, do not support an overall deterministic trend in the time series of Arctic sea ice extent. Therefore, alternative parametrizations such as long-range dependence should be considered for characterising long-term Arctic sea ice variability.

Beyond Thin Ice: Co-Communicating the Many Arctics

NASA Astrophysics Data System (ADS)

Druckenmiller, M. L.; Francis, J. A.; Huntington, H.

2015-12-01

Science communication, typically defined as informing non-expert communities of societally relevant science, is persuaded by the magnitude and pace of scientific discoveries, as well as the urgency of societal issues wherein science may inform decisions. Perhaps nowhere is the connection between these facets stronger than in the marine and coastal Arctic where environmental change is driving advancements in our understanding of natural and socio-ecological systems while paving the way for a new assortment of arctic stakeholders, who generally lack adequate operational knowledge. As such, the Arctic provides opportunity to advance the role of science communication into a collaborative process of engagement and co-communication. To date, the communication of arctic change falls within four primary genres, each with particular audiences in mind. The New Arctic communicates an arctic of new stakeholders scampering to take advantage of unprecedented access. The Global Arctic conveys the Arctic's importance to the rest of the world, primarily as a regulator of lower-latitude climate and weather. The Intra-connected Arctic emphasizes the increasing awareness of the interplay between system components, such as between sea ice loss and marine food webs. The Transforming Arctic communicates the region's trajectory relative to the historical Arctic, acknowledging the impacts on indigenous peoples. The broad societal consensus on climate change in the Arctic as compared to other regions in the world underscores the opportunity for co-communication. Seizing this opportunity requires the science community's engagement with stakeholders and indigenous peoples to construct environmental change narratives that are meaningful to climate responses relative to non-ecological priorities (e.g., infrastructure, food availability, employment, or language). Co-communication fosters opportunities for new methods of and audiences for communication, the co-production of new interdisciplinary

Exploring Arctic history through scientific drilling

NASA Astrophysics Data System (ADS)

ODP Leg 151 Shipboard Scientific Party

During the brief Arctic summer of 1993, the Ocean Drilling Program's research vessel JOIDES Resolution recovered the first scientific drill cores from the eastern Arctic Ocean. Dodging rafts of pack ice shed from the Arctic ice cap, the science party sampled sediments north of 80°N latitude from the Yermak Plateau, as well as from sites in Fram Strait, the northeastern Greenland margin, and the Iceland Plateau (Figure 1).The sediments collected reveal the earliest history of the connection between the North Atlantic and Arctic Oceans through the Nordic Seas. The region between Greenland and Norway first formed a series of isolated basins, sometimes with restricted deep circulation, that eventually joined and allowed deep and surface Arctic Ocean water to invade the region. A record was also retrieved that shows major glaciation in the region began about 2.5 m.y.a.

Dynamical amplification of Arctic and global warming

NASA Astrophysics Data System (ADS)

Alekseev, Genrikh; Ivanov, Nikolai; Kharlanenkova, Natalia; Kuzmina, Svetlana; Bobylev, Leonid; Gnatiuk, Natalia; Urazgildeeva, Aleksandra

2015-04-01

The Arctic is coupled with global climate system by the atmosphere and ocean circulation that provides a major contribution to the Arctic energy budget. Therefore increase of meridional heat transport under global warming can impact on its Arctic amplification. Contribution of heat transport to the recent warming in the Arctic, Northern Hemisphere and the globe are estimated on base of reanalysis data, global climate model data and proposed special index. It is shown that significant part of linear trend during last four decades in average surface air temperature in these areas can be attributed to dynamical amplification. This attribution keeps until 400 mb height with progressive decreasing. The Arctic warming is amplified also due to an increase of humidity and cloudiness in the Arctic atmosphere that follow meridional transport gain. From October to January the Arctic warming trends are amplified as a result of ice edge retreat from the Siberian and Alaska coast and the heating of expanded volume of sea water. This investigation is supported with RFBR project 15-05-03512.

Pan-Arctic distributions of continental runoff in the Arctic Ocean

PubMed Central

Fichot, Cédric G.; Kaiser, Karl; Hooker, Stanford B.; Amon, Rainer M. W.; Babin, Marcel; Bélanger, Simon; Walker, Sally A.; Benner, Ronald

2013-01-01

Continental runoff is a major source of freshwater, nutrients and terrigenous material to the Arctic Ocean. As such, it influences water column stratification, light attenuation, surface heating, gas exchange, biological productivity and carbon sequestration. Increasing river discharge and thawing permafrost suggest that the impacts of continental runoff on these processes are changing. Here, a new optical proxy was developed and implemented with remote sensing to determine the first pan-Arctic distribution of terrigenous dissolved organic matter (tDOM) and continental runoff in the surface Arctic Ocean. Retrospective analyses revealed connections between the routing of North American runoff and the recent freshening of the Canada Basin, and indicated a correspondence between climate-driven changes in river discharge and tDOM inventories in the Kara Sea. By facilitating the real-time, synoptic monitoring of tDOM and freshwater runoff in surface polar waters, this novel approach will help understand the manifestations of climate change in this remote region. PMID:23316278

Pan-Arctic distributions of continental runoff in the Arctic Ocean.

PubMed

Fichot, Cédric G; Kaiser, Karl; Hooker, Stanford B; Amon, Rainer M W; Babin, Marcel; Bélanger, Simon; Walker, Sally A; Benner, Ronald

2013-01-01

Continental runoff is a major source of freshwater, nutrients and terrigenous material to the Arctic Ocean. As such, it influences water column stratification, light attenuation, surface heating, gas exchange, biological productivity and carbon sequestration. Increasing river discharge and thawing permafrost suggest that the impacts of continental runoff on these processes are changing. Here, a new optical proxy was developed and implemented with remote sensing to determine the first pan-Arctic distribution of terrigenous dissolved organic matter (tDOM) and continental runoff in the surface Arctic Ocean. Retrospective analyses revealed connections between the routing of North American runoff and the recent freshening of the Canada Basin, and indicated a correspondence between climate-driven changes in river discharge and tDOM inventories in the Kara Sea. By facilitating the real-time, synoptic monitoring of tDOM and freshwater runoff in surface polar waters, this novel approach will help understand the manifestations of climate change in this remote region.

Strategic Assessment for Arctic Observing, and the New Arctic Observing Viewer

NASA Astrophysics Data System (ADS)

Kassin, A.; Cody, R. P.; Manley, W. F.; Gaylord, A. G.; Dover, M.; Score, R.; Lin, D. H.; Villarreal, S.; Quezada, A.; Tweedie, C. E.

2013-12-01

Although a great deal of progress has been made with various Arctic Observing efforts, it can be difficult to assess that progress. What data collection efforts are established or under way? Where? By whom? To help meet the strategic needs of SEARCH-AON, SAON, and related initiatives, a new resource has been released: the Arctic Observing Viewer (AOV; http://ArcticObservingViewer.org). This web mapping application covers the 'who', 'what', 'where', and 'when' of data collection sites - wherever marine or terrestrial data are collected. Hundreds of sites are displayed, providing an overview as well as details. Users can visualize, navigate, select, search, draw, print, and more. This application currently showcases a subset of observational activities and will become more comprehensive with time. The AOV is founded on principles of interoperability, with an emerging metadata standard and compatible web service formats, such that participating agencies and organizations can use the AOV tools and services for their own purposes. In this way, the AOV will complement other cyber-resources, and will help science planners, funding agencies, PI's, and others to: assess status, identify overlap, fill gaps, assure sampling design, refine network performance, clarify directions, access data, coordinate logistics, collaborate, and more to meet Arctic Observing goals.

Activity of disaccharidases in arctic populations: evolutionary aspects disaccharidases in arctic populations.

PubMed

Kozlov, Andrew; Vershubsky, Galina; Borinskaya, Svetlana; Sokolova, Maria; Nuvano, Vladislav

2005-07-01

Disorders of dietary sugar assimilation occur more often among native people of the Arctic then in temperate climate inhabitants. It is hypothesized that the limited variety of natural exogenous sugars in the Arctic, and their low content in the traditional diets of native northerners in accordance with a "protein-lipid" type of metabolism weakened selection, favoring diversity of disaccharidase enzymes.

An Intensified Arctic Water Cycle? Trend Analysis of the Arctic System Freshwater Cycle: Observations and Expectations

NASA Astrophysics Data System (ADS)

Rawlins, M. A.; Adam, J. C.; Vorosmarty, C. J.; Serreze, M. C.; Hinzman, L. D.; Holland, M.; Shiklomanov, A.

2007-12-01

It is expected that a warming climate will be attended by an intensification of the global hydrological cycle. While there are signs of positive trends in several hydrological quantities emerging at the global scale, the scope, character, and quantitative significance of these changes are not well established. In particular, long-term increases in river discharge across Arctic Eurasia are assumed to represent such an intensification and have received considerable attention. Yet, no change in long-term annual precipitation across the region can be related with the discharge trend. Given linkages and feedbacks between the arctic and global climate systems, a more complete understanding of observed changes across northern high latitudes is needed. We present a working definition of an accelerated or intensified hydrological cycle and a synthesis of long-term (nominally 50 years) trends in observed freshwater stocks and fluxes across the arctic land-atmosphere-ocean system. Trend and significance measures from observed data are described alongside expectations of intensification based on GCM simulations of contemporary and future climate. Our domain of interest includes the terrestrial arctic drainage (including all of Alaska and drainage to Hudson Bay), the Arctic Ocean, and the atmosphere over the land and ocean domains. For the terrestrial Arctic, time series of spatial averages which are derived from station data and atmospheric reanalysis are available. Reconstructed data sets are used for quantities such as Arctic Ocean ice and liquid freshwater transports. Study goals include a comprehensive survey of past changes in freshwater across the pan-arctic and a set of benchmarks for expected changes based on an ensemble of GCM simulations, and identification of potential mechanistic linkages which may be examined with contemporary remote sensing data sets.

The Arctic Research Consortium of the United States (ARCUS)

NASA Astrophysics Data System (ADS)

Fox, S. E.; Wiggins, H. V.; Creek, K. R.

2012-12-01

The Arctic Research Consortium of the United States (ARCUS) is a nonprofit membership organization composed of universities and institutions that have a substantial commitment to research in the Arctic. Founded in 1988 to serve as a forum for advancing interdisciplinary studies of the Arctic, ARCUS synthesizes and disseminates scientific information on arctic research and educates scientists and the general public about the needs and opportunities for research in the Arctic. ARCUS works closely with national and international stakeholders in advancing science planning and educational activities across disciplinary and organizational boundaries. Examples of ARCUS projects include: - Arctic Sea Ice Outlook - an international effort that provides monthly summer reports synthesizing community estimates of the expected sea ice minimum. - Sea Ice for Walrus Outlook - a resource for Alaska Native subsistence hunters, coastal communities, and others that provides weekly reports with information on sea ice conditions relevant to walrus in Alaska waters. - PolarTREC (Teachers and Researchers Exploring and Collaborating) - a program for K-12 educators and researchers to work together in hands-on field experiences in the Arctic and Antarctic to advance polar science education. - ArcticInfo mailing list, Witness the Arctic newsletter, and the Arctic Calendar - communication tools for the arctic community to keep apprised of relevant news, meetings, and announcements. - Project Office for the Study of Environmental Arctic Change (SEARCH) program, which aims to provide scientific understanding of arctic environmental change to help society understand and respond to a rapidly changing Arctic. More information about these and other ARCUS activities can be found at the ARCUS website at: http://www.arcus.org.

The Arctic Research Consortium of the United States (ARCUS)

NASA Astrophysics Data System (ADS)

Creek, K. R.; Fox, S. E.

2013-12-01

The Arctic Research Consortium of the United States (ARCUS) is a nonprofit membership organization composed of universities and institutions that have a substantial commitment to research in the Arctic. Founded in 1988 to serve as a forum for advancing interdisciplinary studies of the Arctic, ARCUS synthesizes and disseminates scientific information on arctic research and educates scientists and the general public about the needs and opportunities for research in the Arctic. ARCUS works closely with national and international stakeholders in advancing science planning and educational activities across disciplinary and organizational boundaries. Examples of ARCUS projects include: - Arctic Sea Ice Outlook - an international effort that provides monthly summer reports synthesizing community estimates of the expected sea ice minimum. - Sea Ice for Walrus Outlook - a resource for Alaska Native subsistence hunters, coastal communities, and others that provides weekly reports with information on sea ice conditions relevant to walrus in Alaska waters. - PolarTREC (Teachers and Researchers Exploring and Collaborating) - a program for K-12 educators and researchers to work together in hands-on field experiences in the Arctic and Antarctic to advance polar science education. - ArcticInfo mailing list, Witness the Arctic newsletter, and the Arctic Calendar - communication tools for the arctic community to keep apprised of relevant news, meetings, and announcements. - Project Office for the Study of Environmental Arctic Change (SEARCH) program, which aims to provide scientific understanding of arctic environmental change to help society understand and respond to a rapidly changing Arctic. More information about these and other ARCUS activities can be found at the ARCUS website at: http://www.arcus.org.

The Arctic Research Consortium of the United States (ARCUS)

NASA Astrophysics Data System (ADS)

Fox, S. E.; Wiggins, H. V.

2011-12-01

The Arctic Research Consortium of the United States (ARCUS) is a nonprofit membership organization composed of universities and institutions that have a substantial commitment to research in the Arctic. ARCUS was formed in 1988 to serve as a forum for planning, facilitating, coordinating, and implementing interdisciplinary studies of the Arctic; to act as a synthesizer and disseminator of scientific information on arctic research; and to educate scientists and the general public about the needs and opportunities for research in the Arctic. ARCUS, in collaboration with the broader science community, relevant agencies and organizations, and other stakeholders, coordinates science planning and educational activities across disciplinary and organizational boundaries. Examples of ARCUS projects include: - Arctic Sea Ice Outlook - an international effort that provides monthly summer reports synthesizing community estimates of the expected sea ice minimum. - Sea Ice for Walrus Outlook - a resource for Alaska Native subsistence hunters, coastal communities, and others that provides weekly reports with information on sea ice conditions relevant to walrus in Alaska waters. - PolarTREC (Teachers and Researchers Exploring and Collaborating) - a program whereby K-12 educators and researchers work together in hands-on field experiences in the Arctic and Antarctic to advance polar science education. - ArcticInfo mailing list, Witness the Arctic newsletter, and the Arctic Calendar - communication tools for the arctic science community to keep apprised of relevant news, meetings, and announcements. - Coordination for the Study of Environmental Arctic Change (SEARCH) program, which aims to provide scientific understanding of arctic environmental change to help society understand and respond to a rapidly changing Arctic.

Physical and Optical/Radiative Properties of Arctic Aerosols: Potential Effects on Arctic Climate

NASA Technical Reports Server (NTRS)

Pueschel, R. F.; Kinne, S. A.; Gore, Warren J. (Technical Monitor)

1994-01-01

We have determined the abundance of light-scattering sulfuric acid (H2SO4/H2O) and light-absorbing black carbon aerosol (BCA) in Spring 1992 in the Arctic atmosphere by airborne in situ sampling with impactors, and measured particle sizes and morphologies by scanning electron microscopy. The mass of BCA in the Arctic troposphere is one percent of the total aerosol, reduced to one part in 104 in the stratosphere. A Mie algorithm permits the calculation of the optical properties of the various aerosol components, and an algorithm developed by Ackerman and Toon and modified to serve our needs lets us calculate the optical effects of the black carbon aerosol that is mixed internally with the sulfuric acid aerosol. It follows that the effect of internally-mixed BCA on the aerosol scattering and absorption properties depends on its location within the droplet. BCA concentrated near the droplet surface has a greater effect on absorption of solar radiation than does the same amount of BCA located near its center. Single scatter albedos of the combined system are omega(sub 0)=1.0 in the post-Pinatubo Arctic stratosphere, and as low as 0.94 in the troposphere. The aerosol has the potential to regionally warm the Arctic earth-atmosphere system, because of the high surface albedo of the snow-covered Arctic.

NATO’s Future Role in the Arctic

DTIC Science & Technology

2016-05-01

iv Global Climate Change and Arctic Geopolitics............................. Error! Bookmark not defined. Russian Claims to the Arctic...13 1 Global Climate Change and Arctic Geopolitics Global climate change has a profound...explaining the effect of climate change in the Arctic and the consequences on regional security. Issues regarding territorial sovereignty will be

ArcticDEM Validation and Accuracy Assessment

NASA Astrophysics Data System (ADS)

Candela, S. G.; Howat, I.; Noh, M. J.; Porter, C. C.; Morin, P. J.

2017-12-01

ArcticDEM comprises a growing inventory Digital Elevation Models (DEMs) covering all land above 60°N. As of August, 2017, ArcticDEM had openly released 2-m resolution, individual DEM covering over 51 million km2, which includes areas of repeat coverage for change detection, as well as over 15 million km2 of 5-m resolution seamless mosaics. By the end of the project, over 80 million km2 of 2-m DEMs will be produced, averaging four repeats of the 20 million km2 Arctic landmass. ArcticDEM is produced from sub-meter resolution, stereoscopic imagery using open source software (SETSM) on the NCSA Blue Waters supercomputer. These DEMs have known biases of several meters due to errors in the sensor models generated from satellite positioning. These systematic errors are removed through three-dimensional registration to high-precision Lidar or other control datasets. ArcticDEM is registered to seasonally-subsetted ICESat elevations due its global coverage and high report accuracy ( 10 cm). The vertical accuracy of ArcticDEM is then obtained from the statistics of the fit to the ICESat point cloud, which averages -0.01 m ± 0.07 m. ICESat, however, has a relatively coarse measurement footprint ( 70 m) which may impact the precision of the registration. Further, the ICESat data predates the ArcticDEM imagery by a decade, so that temporal changes in the surface may also impact the registration. Finally, biases may exist between different the different sensors in the ArcticDEM constellation. Here we assess the accuracy of ArcticDEM and the ICESat registration through comparison to multiple high-resolution airborne lidar datasets that were acquired within one year of the imagery used in ArcticDEM. We find the ICESat dataset is performing as anticipated, introducing no systematic bias during the coregistration process, and reducing vertical errors to within the uncertainty of the airborne Lidars. Preliminary sensor comparisons show no significant difference post coregistration

Arctic tipping points: governance in turbulent times.

PubMed

Young, Oran R

2012-02-01

Interacting forces of climate change and globalization are transforming the Arctic. Triggered by a non-linear shift in sea ice, this transformation has unleashed mounting interest in opportunities to exploit the region's natural resources as well as growing concern about environmental, economic, and political issues associated with such efforts. This article addresses the implications of this transformation for governance, identifies limitations of existing arrangements, and explores changes needed to meet new demands. It advocates the development of an Arctic regime complex featuring flexibility across issues and adaptability over time along with an enhanced role for the Arctic Council both in conducting policy-relevant assessments and in promoting synergy in interactions among the elements of the emerging Arctic regime complex. The emphasis throughout is on maximizing the fit between the socioecological features of the Arctic and the character of the governance arrangements needed to steer the Arctic toward a sustainable future.

Atmospheric Form Drag Coefficients Over Arctic Sea Ice Using Remotely Sensed Ice Topography Data, Spring 2009-2015

NASA Technical Reports Server (NTRS)

Petty, Alek A.; Tsamados, Michel C.; Kurtz, Nathan T.

2017-01-01

Sea ice topography significantly impacts turbulent energy/momentum exchange, e.g., atmospheric (wind) drag, over Arctic sea ice. Unfortunately, observational estimates of this contribution to atmospheric drag variability are spatially and temporally limited. Here we present new estimates of the neutral atmospheric form drag coefficient over Arctic sea ice in early spring, using high-resolution Airborne Topographic Mapper elevation data from NASA's Operation IceBridge mission. We utilize a new three-dimensional ice topography data set and combine this with an existing parameterization scheme linking surface feature height and spacing to form drag. To be consistent with previous studies investigating form drag, we compare these results with those produced using a new linear profiling topography data set. The form drag coefficient from surface feature variability shows lower values [less than 0.5-1 × 10(exp. -3)] in the Beaufort/Chukchi Seas, compared with higher values [greater than 0.5-1 ×10(exp. -3)] in the more deformed ice regimes of the Central Arctic (north of Greenland and the Canadian Archipelago), which increase with coastline proximity. The results show moderate interannual variability, including a strong increase in the form drag coefficient from 2013 to 2014/2015 north of the Canadian Archipelago. The form drag coefficient estimates are extrapolated across the Arctic with Advanced Scatterometer satellite radar backscatter data, further highlighting the regional/interannual drag coefficient variability. Finally, we combine the results with existing parameterizations of form drag from floe edges (a function of ice concentration) and skin drag to produce, to our knowledge, the first pan-Arctic estimates of the total neutral atmospheric drag coefficient (in early spring) from 2009 to 2015.

Sensitivity of Arctic carbon in a changing climate

Treesearch

A. David McGuire; Henry P. Huntington; Simon Wilson

2009-01-01

The Arctic has been warming rapidly in the past few decades. A key question is how that warming will affect the cycling of carbon (C) in the Arctic system. At present, the Arctic is a global sink for C. If that changes and the Arctic becomes a carbon source, global climate warming may speed up.

High Arctic sea ice conditions influence marine birds wintering in Low Arctic regions

NASA Astrophysics Data System (ADS)

McFarlane Tranquilla, Laura; Hedd, April; Burke, Chantelle; Montevecchi, William A.; Regular, Paul M.; Robertson, Gregory J.; Stapleton, Leslie Ann; Wilhelm, Sabina I.; Fifield, David A.; Buren, Alejandro D.

2010-09-01

Ocean climate change is having profound biological effects in polar regions. Such change can also have far-reaching downstream effects in sub-polar regions. This study documents an environmental relationship between High Arctic sea ice changes and mortality events of marine birds in Low Arctic coastal regions. During April 2007 and March 2009, hundreds of beached seabird carcasses and moribund seabirds were found along the east and northeast coasts of Newfoundland, Canada. These seabird "wrecks" (i.e. dead birds on beaches) coincided with a period of strong, persistent onshore winds and heavily-accumulated sea ice that blocked bays and trapped seabirds near beaches. Ninety-two percent of wreck seabirds were Thick-billed Murres ( Uria lomvia). Body condition and demographic patterns of wreck murres were compared to Thick-billed Murres shot in the Newfoundland murre hunt. Average body and pectoral masses of wreck carcasses were 34% and 40% lighter (respectively) than shot murres, indicating that wreck birds had starved. The acute nature of each wreck suggested that starvation and associated hypothermia occurred within 2-3 days. In 2007, first-winter murres (77%) dominated the wreck. In 2009, there were more adults (78%), mostly females (66%). These results suggest that spatial and temporal segregation in ages and sexes can play a role in differential survival when stochastic weather conditions affect discrete areas where these groups aggregate. In wreck years, southward movement of Arctic sea ice to Low Arctic latitudes was later and blocked bays longer than in most other years. These inshore conditions corresponded with recent climate-driven changes in High Arctic ice break-up and ice extent; coupled with local weather conditions, these ice conditions appeared to be the key environmental features that precipitated the ice-associated seabird wrecks in the Low Arctic region.

Arctic Glass: Innovative Consumer Technology in Support of Arctic Research

NASA Astrophysics Data System (ADS)

Ruthkoski, T.

2015-12-01

The advancement of cyberinfrastructure on the North Slope of Alaska is drastically limited by location-specific conditions, including: unique geophysical features, remoteness of location, and harsh climate. The associated cost of maintaining this unique cyberinfrastructure also becomes a limiting factor. As a result, field experiments conducted in this region have historically been at a technological disadvantage. The Arctic Glass project explored a variety of scenarios where innovative consumer-grade technology was leveraged as a lightweight, rapidly deployable, sustainable, alternatives to traditional large-scale Arctic cyberinfrastructure installations. Google Glass, cloud computing services, Internet of Things (IoT) microcontrollers, miniature LIDAR, co2 sensors designed for HVAC systems, and portable network kits are several of the components field-tested at the Toolik Field Station as part of this project. Region-specific software was also developed, including a multi featured, voice controlled Google Glass application named "Arctic Glass". Additionally, real-time sensor monitoring and remote control capability was evaluated through the deployment of a small cluster of microcontroller devices. Network robustness was analyzed as the devices delivered streams of abiotic data to a web-based dashboard monitoring service in near real time. The same data was also uploaded synchronously by the devices to Amazon Web Services. A detailed overview of solutions deployed during the 2015 field season, results from experiments utilizing consumer sensors, and potential roles consumer technology could play in support of Arctic science will be discussed.

An Overview of the NASA P-3B Airborne Laboratory

NASA Technical Reports Server (NTRS)

Guillory, Anthony R.; Postell, George W.

2009-01-01

The National Aeronautics and Space Administration (NASA) Wallops Flight Facility (WFF) P-3B Orion is a medium-lift, four engine turbo-prop aircraft that has been reconfigured from a military aircraft to an Earth Science research platform. The aircraft has a long history of supporting science missions, flying on average over 200 hours per year. Examples of research missions that have been flown aboard the aircraft are remote sensing flights to study geophysical parameters including ice-sheet topography and periodic change, soil moisture content, atmospheric aerosol constituents, and beach erosion. Missions are conducted for the purposes of calibration/validation of various NASA and international satellites that monitor climate change as well as process studies and the test of new prototype remote sensing instruments. In recent y ears the focus has been on ice surveys of the Arctic and Antarctic, soil moisture research, and measurements of atmospheric chemistry and radiation sciences. The aircraft has been conducting ice surveys of Greenland since 1993 for the purposes of topographic mapping of both the surface and basal topography. Another application of the aircraft has been for soil moisture research. Research has also been conducted using microwave radiometers and radars over various agricultural and forest lands. Recently, a mission was flown in the spring over the High-Arctic to collect air samples of haze and boreal forest fires in an effort to determine anthropogenic amounts and sources of pollution. This pa per will provide an overview of the P-3B platform and highlight recent science missions.

Development of pan-Arctic database for river chemistry

USGS Publications Warehouse

McClelland, J.W.; Holmes, R.M.; Peterson, B.J.; Amon, R.; Brabets, T.; Cooper, L.; Gibson, J.; Gordeev, V.V.; Guay, C.; Milburn, D.; Staples, R.; Raymond, P.A.; Shiklomanov, I.; Striegl, Robert G.; Zhulidov, A.; Gurtovaya, T.; Zimov, S.

2008-01-01

More than 10% of all continental runoff flows into the Arctic Ocean. This runoff is a dominant feature of the Arctic Ocean with respect to water column structure and circulation. Yet understanding of the chemical characteristics of runoff from the pan-Arctic watershed is surprisingly limited. The Pan- Arctic River Transport of Nutrients, Organic Matter, and Suspended Sediments ( PARTNERS) project was initiated in 2002 to help remedy this deficit, and an extraordinary data set has emerged over the past few years as a result of the effort. This data set is publicly available through the Cooperative Arctic Data and Information Service (CADIS) of the Arctic Observing Network (AON). Details about data access are provided below.

Organochlorine contaminant and stable isotope profiles in Arctic fox (Alopex lagopus) from the Alaskan and Canadian Arctic.

PubMed

Hoekstra, P F; Braune, B M; O'Hara, T M; Elkin, B; Solomon, K R; Muir, D C G

2003-01-01

Arctic fox (Alopex lagopus) is a circumpolar species distributed across northern Canada and Alaska. Arctic fox muscle and liver were collected at Barrow, AK, USA (n=18), Holman, NT, Canada (n=20), and Arviat, NU, Canada (n=20) to elucidate the feeding ecology of this species and relate these findings to body residue patterns of organochlorine contaminants (OCs). Stable carbon (delta 13C) and nitrogen (delta 15N) isotope analyses of Arctic fox muscle indicated that trophic position (estimated by delta 15N) is positively correlated with increasing delta 13C values, suggesting that Arctic fox with a predominantly marine-based foraging strategy occupy a higher trophic level than individuals mostly feeding from a terrestrial-based carbon source. At all sites, the rank order for OC groups in muscle was polychlorinated biphenyls (Sigma PCB) > chlordane-related compounds (Sigma CHLOR) > hexachlorocyclohexane (Sigma HCH) > total toxaphene (TOX) > or = chlorobenzenes (Sigma ClBz) > DDT-related isomers (Sigma DDT). In liver, Sigma CHLOR was the most abundant OC group, followed by Sigma PCB > TOX > Sigma HCH > Sigma ClBz > Sigma DDT. The most abundant OC analytes detected from Arctic fox muscle and liver were oxychlordane, PCB-153, and PCB-180. The comparison of delta 15N with OC concentrations indicated that relative trophic position might not accurately predict OC bioaccumulation in Arctic fox. The bioaccumulation pattern of OCs in the Arctic fox is similar to the polar bear. While Sigma PCB concentrations were highly variable, concentrations in the Arctic fox were generally below those associated with the toxicological endpoints for adverse effects on mammalian reproduction. Further research is required to properly elucidate the potential health impacts to this species from exposure to OCs.

Integrating STEM Place-Based, Culturally Responsive and Citizen Science Learning in Exploring the Impacts and Feedbacks of a Changing Arctic

NASA Astrophysics Data System (ADS)

Sparrow, E. B.; Spellman, K. V.; Fabbri, C.; Comiso, J. C.; Chase, M.; Fochesatto, G. J.; Butcher, C. E.; Jones, D.; Bacsujlaky, M.; Yoshikawa, K.; Gho, C. L.; Wegner, K.

2016-12-01

To build capacity in navigating challenges associated with a changing climate, learning in Arctic communities must not only increase STEM and climate change literacy, but also generate new knowledge as the rapid changes occur. Among the new NASA Science Mission Directorate Science Education projects, Arctic and Earth SIGNs (STEM Integrating GLOBE and NASA assets) is providing opportunities for K-12 pre-service and in-service teachers, their students, and lifelong learners to engage in citizen science using the Global Learning and Observations to Benefit the Environment (GLOBE) methods and culturally responsive learning to help address climate change challenges within their unique community, and contribute to hypothesis driven research. This project will weave traditional knowledge and western science, and use ground observations and satellite data and best teaching practices in STEM learning, supported through a NASA cooperative agreement and collaborative partnerships. Implementation will begin in rural Alaska and grow within Alaska and throughout the United States to reach underserved and STEM underrepresented populations, through face-to-face and on-line teaching and learning as well as building partnerships among educators, scientists, local and indigenous experts, institutions, agencies, and learning communities. Partners include research and teaching institutions at the University of Alaska Fairbanks, the Association of Interior Native Educators, the North Slope Borough School District and other school districts, the Kenaitze Tribe Environmental Education program, NASA science education and research programs as well as those of NOAA and NSF, the GLOBE Implementation Office, the 4-H program and others. The program resources and model will be shared and disseminated within the United States and globally through partners for local, national and worldwide use in STEM climate change education and citizen empowerment.

Multidecadal trends in aerosol radiative forcing over the Arctic: Contribution of changes in anthropogenic aerosol to Arctic warming since 1980

NASA Astrophysics Data System (ADS)

Breider, Thomas J.; Mickley, Loretta J.; Jacob, Daniel J.; Ge, Cui; Wang, Jun; Payer Sulprizio, Melissa; Croft, Betty; Ridley, David A.; McConnell, Joseph R.; Sharma, Sangeeta; Husain, Liaquat; Dutkiewicz, Vincent A.; Eleftheriadis, Konstantinos; Skov, Henrik; Hopke, Phillip K.

2017-03-01

Arctic observations show large decreases in the concentrations of sulfate and black carbon (BC) aerosols since the early 1980s. These near-term climate-forcing pollutants perturb the radiative balance of the atmosphere and may have played an important role in recent Arctic warming. We use the GEOS-Chem global chemical transport model to construct a 3-D representation of Arctic aerosols that is generally consistent with observations and their trends from 1980 to 2010. Observations at Arctic surface sites show significant decreases in sulfate and BC mass concentrations of 2-3% per year. We find that anthropogenic aerosols yield a negative forcing over the Arctic, with an average 2005-2010 Arctic shortwave radiative forcing (RF) of -0.19 ± 0.05 W m-2 at the top of atmosphere (TOA). Anthropogenic sulfate in our study yields more strongly negative forcings over the Arctic troposphere in spring (-1.17 ± 0.10 W m-2) than previously reported. From 1980 to 2010, TOA negative RF by Arctic aerosol declined, from -0.67 ± 0.06 W m-2 to -0.19 ± 0.05 W m-2, yielding a net TOA RF of +0.48 ± 0.06 W m-2. The net positive RF is due almost entirely to decreases in anthropogenic sulfate loading over the Arctic. We estimate that 1980-2010 trends in aerosol-radiation interactions over the Arctic and Northern Hemisphere midlatitudes have contributed a net warming at the Arctic surface of +0.27 ± 0.04 K, roughly one quarter of the observed warming. Our study does not consider BC emissions from gas flaring nor the regional climate response to aerosol-cloud interactions or BC deposition on snow.

The changing seasonal climate in the Arctic.

PubMed

Bintanja, R; van der Linden, E C

2013-01-01

Ongoing and projected greenhouse warming clearly manifests itself in the Arctic regions, which warm faster than any other part of the world. One of the key features of amplified Arctic warming concerns Arctic winter warming (AWW), which exceeds summer warming by at least a factor of 4. Here we use observation-driven reanalyses and state-of-the-art climate models in a variety of standardised climate change simulations to show that AWW is strongly linked to winter sea ice retreat through the associated release of surplus ocean heat gained in summer through the ice-albedo feedback (~25%), and to infrared radiation feedbacks (~75%). Arctic summer warming is surprisingly modest, even after summer sea ice has completely disappeared. Quantifying the seasonally varying changes in Arctic temperature and sea ice and the associated feedbacks helps to more accurately quantify the likelihood of Arctic's climate changes, and to assess their impact on local ecosystems and socio-economic activities.

The changing seasonal climate in the Arctic

PubMed Central

Bintanja, R.; van der Linden, E. C.

2013-01-01

Ongoing and projected greenhouse warming clearly manifests itself in the Arctic regions, which warm faster than any other part of the world. One of the key features of amplified Arctic warming concerns Arctic winter warming (AWW), which exceeds summer warming by at least a factor of 4. Here we use observation-driven reanalyses and state-of-the-art climate models in a variety of standardised climate change simulations to show that AWW is strongly linked to winter sea ice retreat through the associated release of surplus ocean heat gained in summer through the ice-albedo feedback (~25%), and to infrared radiation feedbacks (~75%). Arctic summer warming is surprisingly modest, even after summer sea ice has completely disappeared. Quantifying the seasonally varying changes in Arctic temperature and sea ice and the associated feedbacks helps to more accurately quantify the likelihood of Arctic's climate changes, and to assess their impact on local ecosystems and socio-economic activities. PMID:23532038

JPSS Support to the Arctic Testbed

NASA Astrophysics Data System (ADS)

Layns, A. L.

2017-12-01

The Joint Polar Satellite System (JPSS) Proving Ground and Risk Reduction (PGRR) program facilitates initiatives to increase or improve the use and value of JPSS data products in user products, services, and application or service areas. Building on the success of the Fire and Smoke, River Ice and Flooding, and Sounding initiatives, the JPSS Arctic Initiative is the latest endeavor of the JPSS PGRR program to increase of the use of JPSS atmospheric and cryosphere products to improve NOAA's products and services in the Arctic. The major participants in the Arctic Initiative to date are the JPSS program office, National Ice Center (NIC), National Weather Service (NWS) Alaska Sea Ice Program (ASIP), and the National Environmental Satellite, Data, and Information Service (NESDIS) Center for Satellite Applications and Research (STAR). This paper will outline the initiative, the potential benefits of the JPSS data products in the Arctic, and the plans for a product demonstration in 2018 within the NOAA Arctic Testbed.

Marine Corps Equities in the Arctic

DTIC Science & Technology

2013-04-18

reduces the shipping time from Yokohama, Japan, to Hamburg , Germany, by 11 days as compared to the Suez Canal. Ships average approximately a 20...areas within the Arctic Circle. 10 Warming ocean water is causing fisheries to shift north as well. Fish populations usually found in the...people live in the Arctic region. Commercial fishing fleets are following these populations. 29 Russia holds the majority of the Arctic population

Vertical structure of recent Arctic warming.

PubMed

Graversen, Rune G; Mauritsen, Thorsten; Tjernström, Michael; Källén, Erland; Svensson, Gunilla

2008-01-03

Near-surface warming in the Arctic has been almost twice as large as the global average over recent decades-a phenomenon that is known as the 'Arctic amplification'. The underlying causes of this temperature amplification remain uncertain. The reduction in snow and ice cover that has occurred over recent decades may have played a role. Climate model experiments indicate that when global temperature rises, Arctic snow and ice cover retreats, causing excessive polar warming. Reduction of the snow and ice cover causes albedo changes, and increased refreezing of sea ice during the cold season and decreases in sea-ice thickness both increase heat flux from the ocean to the atmosphere. Changes in oceanic and atmospheric circulation, as well as cloud cover, have also been proposed to cause Arctic temperature amplification. Here we examine the vertical structure of temperature change in the Arctic during the late twentieth century using reanalysis data. We find evidence for temperature amplification well above the surface. Snow and ice feedbacks cannot be the main cause of the warming aloft during the greater part of the year, because these feedbacks are expected to primarily affect temperatures in the lowermost part of the atmosphere, resulting in a pattern of warming that we only observe in spring. A significant proportion of the observed temperature amplification must therefore be explained by mechanisms that induce warming above the lowermost part of the atmosphere. We regress the Arctic temperature field on the atmospheric energy transport into the Arctic and find that, in the summer half-year, a significant proportion of the vertical structure of warming can be explained by changes in this variable. We conclude that changes in atmospheric heat transport may be an important cause of the recent Arctic temperature amplification.

Sources and Removal of Springtime Arctic Aerosol

NASA Astrophysics Data System (ADS)

Willis, M. D.; Burkart, J.; Bozem, H.; Kunkel, D.; Schulz, H.; Hanna, S.; Aliabadi, A. A.; Bertram, A. K.; Hoor, P. M.; Herber, A. B.; Leaitch, R.; Abbatt, J.

2017-12-01

The sources and removal mechanisms of pollution transported to Arctic regions are key factors in controlling the impact of short-lived climate forcing agents on Arctic climate. We lack a predictive understanding of pollution transport to Arctic regions largely due to poor understanding of removal mechanisms and aerosol chemical and physical processing both within the Arctic and during transport. We present vertically resolved observations of aerosol physical and chemical properties in High Arctic springtime. While much previous work has focused on characterizing episodic events of high pollutant concentrations transported to Arctic regions, here we focus on measurements made under conditions consistent with chronic Arctic Haze, which is more representative of the pollution seasonal maximum observed at long term monitoring stations. On six flights based at Alert and Eureka, Nunavut, Canada, we observe evidence for vertical variations in both aerosol sources and removal mechanisms. With support from model calculations, we show evidence for sources of partially neutralized aerosol with higher organic aerosol (OA) and black carbon content in the middle troposphere, compared to lower tropospheric aerosol with higher amounts of acidic sulfate. Further, we show evidence for aerosol depletion relative to carbon monoxide, both in the mid-to-upper troposphere and within the Arctic Boundary Layer (ABL). Dry deposition, with relatively low removal efficiency, was responsible for aerosol removal in the ABL while ice or liquid-phase scavenging was responsible for aerosol removal at higher altitudes during transport. Overall, we find that vertical variations in both regional and remote aerosol sources, and removal mechanisms, combine with long aerosol residence times to drive the properties of springtime Arctic aerosol.

Arctic air pollution: A Norwegian perspective

NASA Astrophysics Data System (ADS)

Ottar, B.

The paper gives a survey of the results obtained during a research programme in the Norwegian Arctic, financed by British Petroleum Ltd. during the period 1981-1986 under an agreement between the Norwegian Government and the oil companies. The programme included extensive measurement programmes by aircraft and at ground stations, as well as modelling of the transport of air pollutants to the Arctic. The results show that the Arctic plays an important role as an intermediate station in the general dispersion of air pollutants within the Northern Hemisphere. Continued measurements in the Arctic may therefore provide essential information concerning such questions as the change of climate and the global dispersion of polychlorinated hydrocarbons and other halogenated organics.

A Recommended Set of Key Arctic Indicators

NASA Astrophysics Data System (ADS)

Stanitski, D.; Druckenmiller, M.; Fetterer, F. M.; Gerst, M.; Intrieri, J. M.; Kenney, M. A.; Meier, W.; Overland, J. E.; Stroeve, J.; Trainor, S.

2017-12-01

The Arctic is an interconnected and environmentally sensitive system of ice, ocean, land, atmosphere, ecosystems, and people. From local to pan-Arctic scales, the area has already undergone major changes in physical and societal systems and will continue at a pace that is greater than twice the global average. Key Arctic indicators can quantify these changes. Indicators serve as the bridge between complex information and policy makers, stakeholders, and the general public, revealing trends and information people need to make important socioeconomic decisions. This presentation evaluates and compiles more than 70 physical, biological, societal and economic indicators into an approachable summary that defines the changing Arctic. We divided indicators into "existing," "in development," "possible," and "aspirational". In preparing a paper on Arctic Indicators for a special issue of the journal Climatic Change, our group established a set of selection criteria to identify indicators to specifically guide decision-makers in their responses to climate change. A goal of the analysis is to select a manageable composite list of recommended indicators based on sustained, reliable data sources with known user communities. The selected list is also based on the development of a conceptual model that identifies components and processes critical to our understanding of the Arctic region. This list of key indicators is designed to inform the plans and priorities of multiple groups such as the U.S. Global Change Research Program (USGCRP), Interagency Arctic Research Policy Committee (IARPC), and the Arctic Council.

Fresh Water Content Variability in the Arctic Ocean

NASA Technical Reports Server (NTRS)

Hakkinen, Sirpa; Proshutinsky, Andrey

2003-01-01

Arctic Ocean model simulations have revealed that the Arctic Ocean has a basin wide oscillation with cyclonic and anticyclonic circulation anomalies (Arctic Ocean Oscillation; AOO) which has a prominent decadal variability. This study explores how the simulated AOO affects the Arctic Ocean stratification and its relationship to the sea ice cover variations. The simulation uses the Princeton Ocean Model coupled to sea ice. The surface forcing is based on NCEP-NCAR Reanalysis and its climatology, of which the latter is used to force the model spin-up phase. Our focus is to investigate the competition between ocean dynamics and ice formation/melt on the Arctic basin-wide fresh water balance. We find that changes in the Atlantic water inflow can explain almost all of the simulated fresh water anomalies in the main Arctic basin. The Atlantic water inflow anomalies are an essential part of AOO, which is the wind driven barotropic response to the Arctic Oscillation (AO). The baroclinic response to AO, such as Ekman pumping in the Beaufort Gyre, and ice meldfreeze anomalies in response to AO are less significant considering the whole Arctic fresh water balance.

The Arctic Circle

NASA Astrophysics Data System (ADS)

McDonald, Siobhan

2016-04-01

My name is Siobhan McDonald. I am a visual artist living and working in Dublin. My studio is based in The School of Science at University College Dublin where I was Artist in Residence 2013-2015. A fascination with time and the changeable nature of landmass has led to ongoing conversations with scientists and research institutions across the interweaving disciplines of botany, biology and geology. I am developing a body of work following a recent research trip to the North Pole where I studied the disappearing landscape of the Arctic. Prompted by my experience of the Arctic shelf receding, this new work addresses issues of the instability of the earth's materiality. The work is grounded in an investigation of material processes, exploring the dynamic forces that transform matter and energy. This project combines art and science in a fascinating exploration of one of the Earth's last relatively untouched wilderness areas - the High Arctic to bring audiences on journeys to both real and artistically re-imagined Arctic spaces. CRYSTALLINE'S pivotal process is collaboration: with The European Space Agency; curator Helen Carey; palaeontologist Prof. Jenny McElwain, UCD; and with composer Irene Buckley. CRYSTALLINE explores our desire to make corporeal contact with geological phenomena in Polar Regions. From January 2016, in my collaboration with Jenny McElwain, I will focus on the study of plants and atmospheres from the Arctic regions as far back as 400 million years ago, to explore the essential 'nature' that, invisible to the eye, acts as imaginary portholes into other times. This work will be informed by my arctic tracings of sounds and images recorded in the glaciers of this disappearing frozen landscape. In doing so, the urgencies around the tipping of natural balances in this fragile region will be revealed. The final work will emerge from my forthcoming residency at the ESA in spring 2016. Here I will conduct a series of workshops in ESA Madrid to work with

Vole abundance and reindeer carcasses determine breeding activity of Arctic foxes in low Arctic Yamal, Russia.

PubMed

Ehrich, Dorothee; Cerezo, Maite; Rodnikova, Anna Y; Sokolova, Natalya A; Fuglei, Eva; Shtro, Victor G; Sokolov, Aleksandr A

2017-09-16

High latitude ecosystems are at present changing rapidly under the influence of climate warming, and specialized Arctic species at the southern margin of the Arctic may be particularly affected. The Arctic fox (Vulpes lagopus), a small mammalian predator endemic to northern tundra areas, is able to exploit different resources in the context of varying tundra ecosystems. Although generally widespread, it is critically endangered in subarctic Fennoscandia, where a fading out of the characteristic lemming cycles and competition with abundant red foxes have been identified as main threats. We studied an Arctic fox population at the Erkuta Tundra Monitoring site in low Arctic Yamal (Russia) during 10 years in order to determine which resources support the breeding activity in this population. In the study area, lemmings have been rare during the last 15 years and red foxes are nearly absent, creating an interesting contrast to the situation in Fennoscandia. Arctic fox was breeding in nine of the 10 years of the study. The number of active dens was on average 2.6 (range 0-6) per 100 km 2 and increased with small rodent abundance. It was also higher after winters with many reindeer carcasses, which occurred when mortality was unusually high due to icy pastures following rain-on-snow events. Average litter size was 5.2 (SD = 2.1). Scat dissection suggested that small rodents (mostly Microtus spp.) were the most important prey category. Prey remains observed at dens show that birds, notably waterfowl, were also an important resource in summer. The Arctic fox in southern Yamal, which is part of a species-rich low Arctic food web, seems at present able to cope with a state shift of the small rodent community from high amplitude cyclicity with lemming dominated peaks, to a vole community with low amplitude fluctuations. The estimated breeding parameters characterized the population as intermediate between the lemming fox and the coastal fox ecotype. Only continued

Arctic Security in a Warming World

DTIC Science & Technology

2010-03-01

2009). 3 Map based on: “Northwest Passage - Map of Arctic Sea Ice: Global Warming is Opening Canada’s Arctic” http://geology.com/articles/northwest...War College, February 17, 2009) 3. 5 Scott G. Borgerson, “Arctic Meltdown: the Economic and Security Implications of Global Warming ”, Foreign Affairs...april/kirkpatrick.pdf (accessed February 10, 2010). 45 Thomas R. McCarthy, Jr., Global Warming Threatens National Interests in the Arctic, Strategy

The Arctic Research Consortium of the United States (ARCUS)

NASA Astrophysics Data System (ADS)

Wiggins, H. V.; Warnick, W. K.

2008-12-01

The Arctic Research Consortium of the United States (ARCUS) is a nonprofit membership organization composed of universities and institutions that have a substantial commitment to research in the Arctic. ARCUS was formed in 1988 to serve as a forum for planning, facilitating, coordinating, and implementing interdisciplinary studies of the Arctic; to act as a synthesizer and disseminator of scientific information on arctic research; and to educate scientists and the general public about the needs and opportunities for research in the Arctic. ARCUS, in collaboration with the broader science community, relevant agencies and organizations, and other stakeholders, coordinates science planning and educational activities across disciplinary and organizational boundaries. Examples of current ARCUS science planning activities include: serving as the project office for the multi- agency Study of Environmental Arctic Change (SEARCH) program, providing support to the related Bering Ecosystem Study (BEST), and serving as the Science Management Office for the National Science Foundation (NSF) Arctic System Science (ARCSS) Program. ARCUS" central educational activity is PolarTREC (Teachers and Researchers Exploring and Collaborating), an International Polar Year (IPY) program whereby K-12 educators and researchers work together in hands-on field experiences in the Arctic and Antarctic to advance polar science education. Additional science planning, educational, information, and outreach activities include, among many others, the Witness the Arctic newsletter, the Arctic Visiting Speakers" Series, the ArcticInfo listserve, the Internet Media Archive (IMA), and the annual Arctic Forum conference. More information about these and other ARCUS activities can be found at the ARCUS website at: http://www.arcus.org.

The Arctic Research Consortium of the United States (ARCUS)

NASA Astrophysics Data System (ADS)

Creek, K. R.; Fox, S. E.; Wiggins, H. V.

2010-12-01

The Arctic Research Consortium of the United States (ARCUS) is a nonprofit membership organization composed of universities and institutions that have a substantial commitment to research in the Arctic. ARCUS was formed in 1988 to serve as a forum for planning, facilitating, coordinating, and implementing interdisciplinary studies of the Arctic; to act as a synthesizer and disseminator of scientific information on arctic research; and to educate scientists and the general public about the needs and opportunities for research in the Arctic. ARCUS, in collaboration with the broader science community, relevant agencies and organizations, and other stakeholders, coordinates science planning and educational activities across disciplinary and organizational boundaries. Examples of current ARCUS science planning activities include: serving as the project office for the multi-agency Study of Environmental Arctic Change (SEARCH) program, providing support to the related Bering Ecosystem Study (BEST), and serving as the Science Management Office for the National Science Foundation (NSF) Arctic System Science (ARCSS) Program. ARCUS’ central educational activity is PolarTREC (Teachers and Researchers Exploring and Collaborating), an International Polar Year (IPY) program whereby K-12 educators and researchers work together in hands-on field experiences in the Arctic and Antarctic to advance polar science education. Additional science planning, educational, information, and outreach activities include, among many others, the Witness the Arctic newsletter, the Arctic Visiting Speakers’ Series, the ArcticInfo listserve, the Internet Media Archive (IMA), and the annual Arctic Forum conference. More information about these and other ARCUS activities can be found at the ARCUS website at: http://www.arcus.org.

Does the Arctic Amplification peak this decade?

NASA Astrophysics Data System (ADS)

Martin, Torge; Haine, Thomas W. N.

2017-04-01

Temperatures rise faster in the Arctic than on global average, a phenomenon known as Arctic Amplification. While this is well established from observations and model simulations, projections of future climate (here: RCP8.5) with models of the Coupled Model Intercomparison Project phase 5 (CMIP5) also indicate that the Arctic Amplification has a maximum. We show this by means of an Arctic Amplification factor (AAF), which we define as the ratio of Arctic mean to global mean surface air temperature (SAT) anomalies. The SAT anomalies are referenced to the period 1960-1980 and smoothed by a 30-year running mean. For October, the multi-model ensemble-mean AAF reaches a maximum in 2017. The maximum moves however to later years as Arctic winter progresses: for the autumn mean SAT (September to November) the maximum AAF is found in 2028 and for winter (December to February) in 2060. Arctic Amplification is driven, amongst others, by the ice-albedo feedback (IAF) as part of the more general surface albedo feedback (involving clouds, snow cover, vegetation changes) and temperature effects (Planck and lapse-rate feedbacks). We note that sea ice retreat and the associated warming of the summer Arctic Ocean are not only an integral part of the IAF but are also involved in the other drivers. In the CMIP5 simulations, the timing of the AAF maximum coincides with the period of fastest ice retreat for the respective month. Presence of at least some sea ice is crucial for the IAF to be effective because of the contrast in surface albedo between ice and open water and the need to turn ocean warming into ice melt. Once large areas of the Arctic Ocean are ice-free, the IAF should be less effective. We thus hypothesize that the ice retreat significantly affects AAF variability and forces a decline of its magnitude after at least half of the Arctic Ocean is ice-free and the ice cover becomes basically seasonal.

Covariance Between Arctic Sea Ice and Clouds Within Atmospheric State Regimes at the Satellite Footprint Level

NASA Technical Reports Server (NTRS)

Taylor, Patrick C.; Kato, Seiji; Xu, Kuan-Man; Cai, Ming

2015-01-01

Understanding the cloud response to sea ice change is necessary for modeling Arctic climate. Previous work has primarily addressed this problem from the interannual variability perspective. This paper provides a refined perspective of sea ice-cloud relationship in the Arctic using a satellite footprint-level quantification of the covariance between sea ice and Arctic low cloud properties from NASA A-Train active remote sensing data. The covariances between Arctic low cloud properties and sea ice concentration are quantified by first partitioning each footprint into four atmospheric regimes defined using thresholds of lower tropospheric stability and mid-tropospheric vertical velocity. Significant regional variability in the cloud properties is found within the atmospheric regimes indicating that the regimes do not completely account for the influence of meteorology. Regional anomalies are used to account for the remaining meteorological influence on clouds. After accounting for meteorological regime and regional influences, a statistically significant but weak covariance between cloud properties and sea ice is found in each season for at least one atmospheric regime. Smaller average cloud fraction and liquid water are found within footprints with more sea ice. The largest-magnitude cloud-sea ice covariance occurs between 500m and 1.2 km when the lower tropospheric stability is between 16 and 24 K. The covariance between low cloud properties and sea ice is found to be largest in fall and is accompanied by significant changes in boundary layer temperature structure where larger average near-surface static stability is found at larger sea ice concentrations.

Covariance between Arctic sea ice and clouds within atmospheric state regimes at the satellite footprint level

PubMed Central

Kato, Seiji; Xu, Kuan‐Man; Cai, Ming

2015-01-01

Abstract Understanding the cloud response to sea ice change is necessary for modeling Arctic climate. Previous work has primarily addressed this problem from the interannual variability perspective. This paper provides a refined perspective of sea ice‐cloud relationship in the Arctic using a satellite footprint‐level quantification of the covariance between sea ice and Arctic low cloud properties from NASA A‐Train active remote sensing data. The covariances between Arctic low cloud properties and sea ice concentration are quantified by first partitioning each footprint into four atmospheric regimes defined using thresholds of lower tropospheric stability and midtropospheric vertical velocity. Significant regional variability in the cloud properties is found within the atmospheric regimes indicating that the regimes do not completely account for the influence of meteorology. Regional anomalies are used to account for the remaining meteorological influence on clouds. After accounting for meteorological regime and regional influences, a statistically significant but weak covariance between cloud properties and sea ice is found in each season for at least one atmospheric regime. Smaller average cloud fraction and liquid water are found within footprints with more sea ice. The largest‐magnitude cloud‐sea ice covariance occurs between 500 m and 1.2 km when the lower tropospheric stability is between 16 and 24 K. The covariance between low cloud properties and sea ice is found to be largest in fall and is accompanied by significant changes in boundary layer temperature structure where larger average near‐surface static stability is found at larger sea ice concentrations. PMID:27818851

Covariance between Arctic sea ice and clouds within atmospheric state regimes at the satellite footprint level.

PubMed

Taylor, Patrick C; Kato, Seiji; Xu, Kuan-Man; Cai, Ming

2015-12-27

Understanding the cloud response to sea ice change is necessary for modeling Arctic climate. Previous work has primarily addressed this problem from the interannual variability perspective. This paper provides a refined perspective of sea ice-cloud relationship in the Arctic using a satellite footprint-level quantification of the covariance between sea ice and Arctic low cloud properties from NASA A-Train active remote sensing data. The covariances between Arctic low cloud properties and sea ice concentration are quantified by first partitioning each footprint into four atmospheric regimes defined using thresholds of lower tropospheric stability and midtropospheric vertical velocity. Significant regional variability in the cloud properties is found within the atmospheric regimes indicating that the regimes do not completely account for the influence of meteorology. Regional anomalies are used to account for the remaining meteorological influence on clouds. After accounting for meteorological regime and regional influences, a statistically significant but weak covariance between cloud properties and sea ice is found in each season for at least one atmospheric regime. Smaller average cloud fraction and liquid water are found within footprints with more sea ice. The largest-magnitude cloud-sea ice covariance occurs between 500 m and 1.2 km when the lower tropospheric stability is between 16 and 24 K. The covariance between low cloud properties and sea ice is found to be largest in fall and is accompanied by significant changes in boundary layer temperature structure where larger average near-surface static stability is found at larger sea ice concentrations.

78 FR 12033 - Programs and Research Projects Affecting the Arctic

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-21

... ARCTIC RESEARCH COMMISSION Programs and Research Projects Affecting the Arctic Notice is hereby given that the U.S. Arctic Research Commission will hold its 100th meeting in Anchorage and Bethel... presentations concerning Arctic research activities The focus of the meeting will be Arctic research activities...

Oceanographic Aspects of Recent Changes in the Arctic

NASA Astrophysics Data System (ADS)

Morison, J. H.

2002-12-01

In the Arctic recent decadal-scale changes have marked the atmosphere, ocean, and land. Connections between the oceanographic changes and large-scale atmospheric circulation changes are emerging. Surface atmospheric pressure has shown a declining trend over the Arctic. In the 1990s, the Arctic Ocean circulation took on a more cyclonic character, and the front separating Atlantic-derived waters of the Eurasian Basin and the Pacific-derived waters of the Canadian Basin shifted counterclockwise. The temperature of Atlantic water in the Arctic Ocean reached record levels. The cold halocline, which isolates the surface from the warm Atlantic water, grew thinner disappearing entirely from the Amundsen Basin at one point [Steele and Boyd, 1998]. Arctic sea ice extent has decreased 3% per decade since the 1970s [Parkinson et al., 1999]. Sea ice thickness over much of the Arctic decreased 43% between 1958-1976 and 1993-1997 [Rothrock et al., 1999]. Arctic ecosystems have responded to these changes. Sea ice studies in the late 1990s indicate that the sea ice algal species composition changed from decades before, with the species recently being characterized by more brackish and freshwater forms. Barents Sea fisheries have shifted north following reductions in ice extent. Pacific salmon species have been found entering rivers in the Arctic. There is evidence that this complex of pan-Arctic changes is connected with the rising trend in the Arctic Oscillation (AO) or Northern Hemisphere atmospheric polar vortex in the 1990s. Theoretical evidence that a positive trend in the AO index might be indicative of greenhouse warming raises the possibility that the recent complex of changes is an Arctic characteristic of global climate change. Also, the changes in ice cover manifest a connection between the complex of change and global climate through ice-albedo feedback, by which reductions in ice cover reduce the amount of sunlight reflected from the earth's surface. Another important

Tipping elements in the Arctic marine ecosystem.

PubMed

Duarte, Carlos M; Agustí, Susana; Wassmann, Paul; Arrieta, Jesús M; Alcaraz, Miquel; Coello, Alexandra; Marbà, Núria; Hendriks, Iris E; Holding, Johnna; García-Zarandona, Iñigo; Kritzberg, Emma; Vaqué, Dolors

2012-02-01

The Arctic marine ecosystem contains multiple elements that present alternative states. The most obvious of which is an Arctic Ocean largely covered by an ice sheet in summer versus one largely devoid of such cover. Ecosystems under pressure typically shift between such alternative states in an abrupt, rather than smooth manner, with the level of forcing required for shifting this status termed threshold or tipping point. Loss of Arctic ice due to anthropogenic climate change is accelerating, with the extent of Arctic sea ice displaying increased variance at present, a leading indicator of the proximity of a possible tipping point. Reduced ice extent is expected, in turn, to trigger a number of additional tipping elements, physical, chemical, and biological, in motion, with potentially large impacts on the Arctic marine ecosystem.

Changing Arctic ecosystems--research to understand and project changes in marine and terrestrial ecosystems of the Arctic

USGS Publications Warehouse

Geiselman, Joy; DeGange, Anthony R.; Oakley, Karen; Derksen, Dirk; Whalen, Mary

2012-01-01

Ecosystems and their wildlife communities are not static; they change and evolve over time due to numerous intrinsic and extrinsic factors. A period of rapid change is occurring in the Arctic for which our current understanding of potential ecosystem and wildlife responses is limited. Changes to the physical environment include warming temperatures, diminishing sea ice, increasing coastal erosion, deteriorating permafrost, and changing water regimes. These changes influence biological communities and the ways in which human communities interact with them. Through the new initiative Changing Arctic Ecosystems (CAE) the U.S. Geological Survey (USGS) strives to (1) understand the potential suite of wildlife population responses to these physical changes to inform key resource management decisions such as those related to the Endangered Species Act, and (2) provide unique insights into how Arctic ecosystems are responding under new stressors. Our studies examine how and why changes in the ice-dominated ecosystems of the Arctic are affecting wildlife and will provide a better foundation for understanding the degree and manner in which wildlife species respond and adapt to rapid environmental change. Changes to Arctic ecosystems will be felt broadly because the Arctic is a production zone for hundreds of species that migrate south for the winter. The CAE initiative includes three major research themes that span Arctic ice-dominated ecosystems and that are structured to identify and understand the linkages between physical processes, ecosystems, and wildlife populations. The USGS is applying knowledge-based modeling structures such as Bayesian Networks to integrate the work.

The Relationship Between Arctic Sea Ice Albedo and the Geophysical Parameters of the Ice Cover

NASA Astrophysics Data System (ADS)

Riihelä, A.

2015-12-01

The Arctic sea ice cover is thinning and retreating. Remote sensing observations have also shown that the mean albedo of the remaining ice cover is decreasing on decadal time scales, albeit with significant annual variability (Riihelä et al., 2013, Pistone et al., 2014). Attribution of the albedo decrease between its different drivers, such as decreasing ice concentration and enhanced surface melt of the ice, remains an important research question for the forecasting of future conditions of the ice cover. A necessary step towards this goal is understanding the relationships between Arctic sea ice albedo and the geophysical parameters of the ice cover. Particularly the question of the relationship between sea ice albedo and ice age is both interesting and not widely studied. The recent changes in the Arctic sea ice zone have led to a substantial decrease of its multi-year sea ice, as old ice melts and is replaced by first-year ice during the next freezing season. It is generally known that younger sea ice tends to have a lower albedo than older ice because of several reasons, such as wetter snow cover and enhanced melt ponding. However, the quantitative correlation between sea ice age and sea ice albedo has not been extensively studied to date, excepting in-situ measurement based studies which are, by necessity, focused on a limited area of the Arctic Ocean (Perovich and Polashenski, 2012).In this study, I analyze the dependencies of Arctic sea ice albedo relative to the geophysical parameters of the ice field. I use remote sensing datasets such as the CM SAF CLARA-A1 (Karlsson et al., 2013) and the NASA MeaSUREs (Anderson et al., 2014) as data sources for the analysis. The studied period is 1982-2009. The datasets are spatiotemporally collocated and analysed. The changes in sea ice albedo as a function of sea ice age are presented for the whole Arctic Ocean and for potentially interesting marginal sea cases. This allows us to see if the the albedo of the older sea

Cyclone Activity in the Arctic From an Ensemble of Regional Climate Models (Arctic CORDEX)

NASA Astrophysics Data System (ADS)

Akperov, Mirseid; Rinke, Annette; Mokhov, Igor I.; Matthes, Heidrun; Semenov, Vladimir A.; Adakudlu, Muralidhar; Cassano, John; Christensen, Jens H.; Dembitskaya, Mariya A.; Dethloff, Klaus; Fettweis, Xavier; Glisan, Justin; Gutjahr, Oliver; Heinemann, Günther; Koenigk, Torben; Koldunov, Nikolay V.; Laprise, René; Mottram, Ruth; Nikiéma, Oumarou; Scinocca, John F.; Sein, Dmitry; Sobolowski, Stefan; Winger, Katja; Zhang, Wenxin

2018-03-01

The ability of state-of-the-art regional climate models to simulate cyclone activity in the Arctic is assessed based on an ensemble of 13 simulations from 11 models from the Arctic-CORDEX initiative. Some models employ large-scale spectral nudging techniques. Cyclone characteristics simulated by the ensemble are compared with the results forced by four reanalyses (ERA-Interim, National Centers for Environmental Prediction-Climate Forecast System Reanalysis, National Aeronautics and Space Administration-Modern-Era Retrospective analysis for Research and Applications Version 2, and Japan Meteorological Agency-Japanese 55-year reanalysis) in winter and summer for 1981-2010 period. In addition, we compare cyclone statistics between ERA-Interim and the Arctic System Reanalysis reanalyses for 2000-2010. Biases in cyclone frequency, intensity, and size over the Arctic are also quantified. Variations in cyclone frequency across the models are partly attributed to the differences in cyclone frequency over land. The variations across the models are largest for small and shallow cyclones for both seasons. A connection between biases in the zonal wind at 200 hPa and cyclone characteristics is found for both seasons. Most models underestimate zonal wind speed in both seasons, which likely leads to underestimation of cyclone mean depth and deep cyclone frequency in the Arctic. In general, the regional climate models are able to represent the spatial distribution of cyclone characteristics in the Arctic but models that employ large-scale spectral nudging show a better agreement with ERA-Interim reanalysis than the rest of the models. Trends also exhibit the benefits of nudging. Models with spectral nudging are able to reproduce the cyclone trends, whereas most of the nonnudged models fail to do so. However, the cyclone characteristics and trends are sensitive to the choice of nudged variables.

The Contribution to Arctic Climate Change from Countries in the Arctic Council

NASA Astrophysics Data System (ADS)

Schultz, T.; MacCracken, M. C.

2013-12-01

The conventional accounting frameworks for greenhouse gas (GHG) emissions used today, established under the Kyoto Protocol 25 years ago, exclude short lived climate pollutants (SLCPs), and do not include regional effects on the climate. However, advances in climate science now suggest that mitigation of SLCPs can reduce up to 50% of global warming by 2050. It has also become apparent that regions such as the Arctic have experienced a much greater degree of anthropogenic warming than the globe as a whole, and that efforts to slow this warming could benefit the larger effort to slow climate change around the globe. A draft standard for life cycle assessment (LCA), LEO-SCS-002, being developed under the American National Standards Institute process, has integrated the most recent climate science into a unified framework to account for emissions of all radiatively significant GHGs and SLCPs. This framework recognizes four distinct impacts to the oceans and climate caused by GHGs and SLCPs: Global Climate Change; Arctic Climate Change; Ocean Acidification; and Ocean Warming. The accounting for Arctic Climate Change, the subject of this poster, is based upon the Absolute Regional Temperature Potential, which considers the incremental change to the Arctic surface temperature resulting from an emission of a GHG or SLCP. Results are evaluated using units of mass of carbon dioxide equivalent (CO2e), which can be used by a broad array of stakeholders, including scientists, consumers, policy makers, and NGOs. This poster considers the contribution to Arctic Climate Change from emissions of GHGs and SLCPs from the eight member countries of the Arctic Council; the United States, Canada, Russia, Denmark, Finland, Iceland, Norway, and Sweden. Of this group of countries, the United States was the largest contributor to Arctic Climate Change in 2011, emitting 9600 MMT CO2e. This includes a gross warming of 11200 MMT CO2e (caused by GHGs, black and brown carbon, and warming effects

Arctic research vessel design would expand science prospects

NASA Astrophysics Data System (ADS)

Elsner, Robert; Kristensen, Dirk

The U.S. polar marine science community has long declared the need for an arctic research vessel dedicated to advancing the study of northern ice-dominated seas. Planning for such a vessel began 2 decades ago, but competition for funding has prevented construction. A new design program is underway, and it shows promise of opening up exciting possibilities for new research initiatives in arctic marine science.With its latest design, the Arctic Research Vessel (ARV) has grown to a size and capability that will make it the first U.S. academic research vessel able to provide access to the Arctic Ocean. This ship would open a vast arena for new studies in the least known of the world's seas. These studies promise to rank high in national priority because of the importance of the Arctic Ocean as a source of data relating to global climate change. Other issues that demand attention in the Arctic include its contributions to the world's heat budget, the climate history buried in its sediments, pollution monitoring, and the influence of arctic conditions on marine renewable resources.

The Impact of Transported Pollution on Arctic Climate

NASA Astrophysics Data System (ADS)

Quinn, P.; Stohl, A.; Arneth, A.; Berntsen, T.; Burkhart, J. F.; Flanner, M. G.; Kupiainen, K.; Shepherd, M.; Shevchenko, V. P.; Skov, H.; Vestreng, V.

2011-12-01

Arctic temperatures have increased at almost twice the global average rate over the past 100 years. Warming in the Arctic has been accompanied by an earlier onset of spring melt, a lengthening of the melt season, changes in the mass balance of the Greenland ice sheet, and a decrease in sea ice extent. Short-lived, climate warming pollutants such as black carbon (BC) have recently gained attention as a target for immediate mitigation of Arctic warming in addition to reductions in long lived greenhouse gases. Model calculations indicate that BC increases surface temperatures within the Arctic primarily through deposition on snow and ice surfaces with a resulting decrease in surface albedo and increase in absorbed solar radiation. In 2009, the Arctic Monitoring and Assessment Program (AMAP) established an Expert Group on BC with the goal of identifying source regions and energy sectors that have the largest impact on Arctic climate. Here we present the results of this work and investigate links between mid-latitude pollutants and Arctic climate.

Multi-model seasonal forecast of Arctic sea-ice: forecast uncertainty at pan-Arctic and regional scales

NASA Astrophysics Data System (ADS)

Blanchard-Wrigglesworth, E.; Barthélemy, A.; Chevallier, M.; Cullather, R.; Fučkar, N.; Massonnet, F.; Posey, P.; Wang, W.; Zhang, J.; Ardilouze, C.; Bitz, C. M.; Vernieres, G.; Wallcraft, A.; Wang, M.

2017-08-01

Dynamical model forecasts in the Sea Ice Outlook (SIO) of September Arctic sea-ice extent over the last decade have shown lower skill than that found in both idealized model experiments and hindcasts of previous decades. Additionally, it is unclear how different model physics, initial conditions or forecast post-processing (bias correction) techniques contribute to SIO forecast uncertainty. In this work, we have produced a seasonal forecast of 2015 Arctic summer sea ice using SIO dynamical models initialized with identical sea-ice thickness in the central Arctic. Our goals are to calculate the relative contribution of model uncertainty and irreducible error growth to forecast uncertainty and assess the importance of post-processing, and to contrast pan-Arctic forecast uncertainty with regional forecast uncertainty. We find that prior to forecast post-processing, model uncertainty is the main contributor to forecast uncertainty, whereas after forecast post-processing forecast uncertainty is reduced overall, model uncertainty is reduced by an order of magnitude, and irreducible error growth becomes the main contributor to forecast uncertainty. While all models generally agree in their post-processed forecasts of September sea-ice volume and extent, this is not the case for sea-ice concentration. Additionally, forecast uncertainty of sea-ice thickness grows at a much higher rate along Arctic coastlines relative to the central Arctic ocean. Potential ways of offering spatial forecast information based on the timescale over which the forecast signal beats the noise are also explored.

NASA IceBridge: Scientific Insights from Airborne Surveys of the Polar Sea Ice Covers

NASA Astrophysics Data System (ADS)

Richter-Menge, J.; Farrell, S. L.

2015-12-01

The NASA Operation IceBridge (OIB) airborne sea ice surveys are designed to continue a valuable series of sea ice thickness measurements by bridging the gap between NASA's Ice, Cloud and Land Elevation Satellite (ICESat), which operated from 2003 to 2009, and ICESat-2, which is scheduled for launch in 2017. Initiated in 2009, OIB has conducted campaigns over the western Arctic Ocean (March/April) and Southern Oceans (October/November) on an annual basis when the thickness of sea ice cover is nearing its maximum. More recently, a series of Arctic surveys have also collected observations in the late summer, at the end of the melt season. The Airborne Topographic Mapper (ATM) laser altimeter is one of OIB's primary sensors, in combination with the Digital Mapping System digital camera, a Ku-band radar altimeter, a frequency-modulated continuous-wave (FMCW) snow radar, and a KT-19 infrared radiation pyrometer. Data from the campaigns are available to the research community at: http://nsidc.org/data/icebridge/. This presentation will summarize the spatial and temporal extent of the OIB campaigns and their complementary role in linking in situ and satellite measurements, advancing observations of sea ice processes across all length scales. Key scientific insights gained on the state of the sea ice cover will be highlighted, including snow depth, ice thickness, surface roughness and morphology, and melt pond evolution.

Changing seasonality of Arctic hydrology disrupts key biotic linkages in Arctic aquatic ecosystems.

NASA Astrophysics Data System (ADS)

Deegan, L.; MacKenzie, C.; Peterson, B. J.; Fishscape Project

2011-12-01

Arctic grayling (Thymallus arcticus) is an important circumpolar species that provide a model system for understanding the impacts of changing seasonality on arctic ecosystem function. Grayling serve as food for other biota, including lake trout, birds and humans, and act as top-down controls in stream ecosystems. In Arctic tundra streams, grayling spend their summers in streams but are obligated to move back into deep overwintering lakes in the fall. Climatic change that affects the seasonality of river hydrology could have a significant impact on grayling populations: grayling may leave overwintering lakes sooner in the spring and return later in the fall due to a longer open water season, but the migration could be disrupted by drought due to increased variability in discharge. In turn, a shorter overwintering season may impact lake trout dynamics in the lakes, which may rely on the seasonal inputs of stream nutrients in the form of migrating grayling into these oligotrophic lakes. To assess how shifting seasonality of Arctic river hydrology may disrupt key trophic linkages within and between lake and stream components of watersheds on the North Slope of the Brooks Mountain Range, Alaska, we have undertaken new work on grayling and lake trout population and food web dynamics. We use Passive Integrated Transponder (PIT) tags coupled with stream-width antenna units to monitor grayling movement across Arctic tundra watersheds during the summer, and into overwintering habitat in the fall. Results indicate that day length may prime grayling migration readiness, but that flooding events are likely the cue grayling use to initiate migration in to overwintering lakes. Many fish used high discharge events in the stream as an opportunity to move into lakes. Stream and lake derived stable isotopes also indicate that lake trout rely on these seasonally transported inputs of stream nutrients for growth. Thus, changes in the seasonality of river hydrology may have broader

Asteroid Redirect Mission Briefing on This Week @NASA – September 19, 2016

NASA Image and Video Library

2016-09-19

On Sept. 14, officials from the White House and NASA discussed the space agency’s Asteroid Redirect Mission (ARM) during a televised event at NASA’s Goddard Space Flight Center. On the mission, which is targeted for launch in Dec. 2021, NASA plans to send a robotic spacecraft to an asteroid tens of millions of miles from Earth, capture a multi-ton boulder, and bring it to an orbit near the moon for future exploration by astronauts on a following mission aboard NASA’s Orion spacecraft. During the live discussion, John Holdren, assistant to President Obama for Science and Technology, NASA Administrator Charles Bolden and ARM Program Director Michele Gates highlighted the mission’s scientific and technological benefits, how the mission will support NASA’s goal of sending humans to Mars in the 2030s, and how it will demonstrate technology relevant to defending Earth from potentially hazardous asteroids. Also, Astronaut Tim Kopra Visits DC Area, The Warmest August in 136 Years, and 2016 Arctic Sea Ice Minimum Ties 2nd Lowest on Record!

Progress report for project modeling Arctic barrier island-lagoon system response to projected Arctic warming

USGS Publications Warehouse

Erikson, Li H.; Gibbs, Ann E.; Richmond, Bruce M.; Storlazzi, Curt; B.M. Jones,

2012-01-01

Changes in Arctic coastal ecosystems in response to global warming may be some of the most severe on the planet. A better understanding and analysis of the rates at which these changes are expected to occur over the coming decades is crucial in order to delineate high-priority areas that are likely to be affected by climate changes. In this study we investigate the likelihood of changes to habitat-supporting barrier island – lagoon systems in response to projected changes in atmospheric and oceanographic forcing associated with Arctic warming. To better understand the relative importance of processes responsible for the current and future coastal landscape, key parameters related to increasing arctic temperatures are investigated and used to establish boundary conditions for models that simulate barrier island migration and inundation of deltaic deposits and low-lying tundra. The modeling effort investigates the dominance and relative importance of physical processes shaping the modern Arctic coastline as well as decadal responses due to projected conditions out to the year 2100.

Arctic reconstruction from an Alaskan viewpoint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crane, R.C.

1985-04-01

Field, seismic, structural, and stratigraphic data were used to reconstruct the geologic history of the Arctic in 10-m.y. time slices from the present to mid-Jurassic - the initial opening of the Arctic Ocean. A basic assumption is that Lomonosov Ridge, Alpha Ridge, Mendeleyev Ridge, and Chukchi Plateau are all foundered continental plates. Opening of the Arctic occurs in two stages: Late Jurassic - Cretaceous for the Canada basin and Neogene for the Eurasian basin. Opening is facilitated by two subparallel transform shears - the Arctic (Kaltag-Porcupine) on the east and the Chukchi on the west. Deformation is essentially tensional onmore » the Barents side of the Arctic and shear-compressional on the Alaska side. The development of Chutkoya, North Slope, Brooks Range, north-west Canada, Seward Peninsula, and central Alaska can be sequentially related to Arctic opening, modified by impingement on the northern terrane of allochthonous terranes arriving from the south - the Pacific plates of Tintina, Denali, Orca (Prince William-Chugach-Yakutat), Anadyr, Khatyrka, Kolyman, and other minor terranes. The North Slope of Alaska, a passive, rifted, subsided margin, is restored to line up with a similar margin on Alpha Ridge. Northeastern Alaska (the Romanzof Mountain area) lines up opposite the north end of the Sverdrup Rim, near Prince Patrick and Borden Islands.« less

Arctic ice islands

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sackinger, W.M.; Jeffries, M.O.; Lu, M.C.

1988-01-01

The development of offshore oil and gas resources in the Arctic waters of Alaska requires offshore structures which successfully resist the lateral forces due to moving, drifting ice. Ice islands are floating, a tabular icebergs, up to 60 meters thick, of solid ice throughout their thickness. The ice islands are thus regarded as the strongest ice features in the Arctic; fixed offshore structures which can directly withstand the impact of ice islands are possible but in some locations may be so expensive as to make oilfield development uneconomic. The resolution of the ice island problem requires two research steps: (1)more » calculation of the probability of interaction between an ice island and an offshore structure in a given region; and (2) if the probability if sufficiently large, then the study of possible interactions between ice island and structure, to discover mitigative measures to deal with the moving ice island. The ice island research conducted during the 1983-1988 interval, which is summarized in this report, was concerned with the first step. Monte Carlo simulations of ice island generation and movement suggest that ice island lifetimes range from 0 to 70 years, and that 85% of the lifetimes are less then 35 years. The simulation shows a mean value of 18 ice islands present at any time in the Arctic Ocean, with a 90% probability of less than 30 ice islands. At this time, approximately 34 ice islands are known, from observations, to exist in the Arctic Ocean, not including the 10-meter thick class of ice islands. Return interval plots from the simulation show that coastal zones of the Beaufort and Chukchi Seas, already leased for oil development, have ice island recurrences of 10 to 100 years. This implies that the ice island hazard must be considered thoroughly, and appropriate safety measures adopted, when offshore oil production plans are formulated for the Alaskan Arctic offshore. 132 refs., 161 figs., 17 tabs.« less

The application of ERTS imagery to monitoring Arctic sea ice. [mapping ice in Bering Sea, Beaufort Sea, Canadian Archipelago, and Greenland Sea

NASA Technical Reports Server (NTRS)

Barnes, J. C. (Principal Investigator); Bowley, C. J.

1974-01-01

The author has identified the following significant results. Because of the effect of sea ice on the heat balance of the Arctic and because of the expanding economic interest in arctic oil and minerals, extensive monitoring and further study of sea ice is required. The application of ERTS data for mapping ice is evaluated for several arctic areas, including the Bering Sea, the eastern Beaufort Sea, parts of the Canadian Archipelago, and the Greenland Sea. Interpretive techniques are discussed, and the scales and types of ice features that can be detected are described. For the Bering Sea, a sample of ERTS-1 imagery is compared with visual ice reports and aerial photography from the NASA CV-990 aircraft. The results of the investigation demonstrate that ERTS-1 imagery has substantial practical application for monitoring arctic sea ice. Ice features as small as 80-100 m in width can be detected, and the combined use of the visible and near-IR imagery is a powerful tool for identifying ice types. Sequential ERTS-1 observations at high latitudes enable ice deformations and movements to be mapped. Ice conditions in the Bering Sea during early March depicted in ERTS-1 images are in close agreement with aerial ice observations and photographs.

Multinational Experiment 7. Maritime Security Region: The Arctic

DTIC Science & Technology

2013-07-08

Russia. Marine Resources The Arctic Ocean is home to countless species from microscopic plankton to gigantic whales . Large-scale commercial...Arctic is a circumpolar region that encompasses both marine and land masses and includes the Arctic Ocean and its seas that cover more than 30...and does not rise on the day of the winter solstice. The Arctic Ocean is the world’s smallest and shallowest, with an average depth of roughly a

Advances in Airborne Altimetric Techniques for the Measurement of Snow on Arctic Sea Ice

NASA Astrophysics Data System (ADS)

Newman, T.; Farrell, S. L.; Richter-Menge, J.; Elder, B. C.; Ruth, J.; Connor, L. N.

2014-12-01

Current sea ice observations and models indicate a transition towards a more seasonal Arctic ice pack with a smaller, and geographically more variable, multiyear ice component. To gain a comprehensive understanding of the processes governing this transition it is important to include the impact of the snow cover, determining the mechanisms by which snow is both responding to and forcing changes to the sea ice pack. Data from NASA's Operation IceBridge (OIB) snow radar system, which has been making yearly surveys of the western Arctic since 2009, offers a key resource for investigating the snow cover. In this work, we characterize the OIB snow radar instrument response to ascertain the location of 'side-lobes', aiding the interpretation of snow radar data. We apply novel wavelet-based techniques to identify the primary reflecting interfaces within the snow pack from which snow depth estimates are derived. We apply these techniques to the range of available snow radar data collected over the last 6 years during the NASA OIB mission. Our results are validated through comparison with a range of in-situ data. We discuss the impact of sea ice surface morphology on snow radar returns (with respect to ice type) and the topographic conditions over which accurate snow-radar-derived snow depths may be obtained. Finally we present improvements to in situ survey design that will allow for both an improved sampling of the snow radar footprint and more accurate assessment of the uncertainties in radar-derived snow depths in the future.

Islands of the Arctic

NASA Astrophysics Data System (ADS)

Dowdeswell, Julian; Hambrey, Michael

2002-11-01

The Arctic islands are characterized by beautiful mountains and glaciers, in which the wildlife lives in delicate balance with its environment. It is a fragile region with a long history of exploration and exploitation that is now experiencing rapid environmental change. All of these themes are explored in Islands of the Arctic, a richly illustrated volume with superb photographs from the Canadian Arctic archipelago, Greenland, Svalbard and the Russian Arctic. It begins with the various processes shaping the landscape: glaciers, rivers and coastal processes, the role of ice in the oceans and the weather and climate. Julian Dowdeswell and Michael Hambrey describe the flora and fauna in addition to the human influences on the environment, from the sustainable approach of the Inuit, to the devastating damage inflicted by hunters and issues arising from the presence of military security installations. Finally, they consider the future prospects of the Arctic islands Julian Dowdeswell is Director of the Scott Polar Research Institute and Professor of Physical Geography at 0he University of Cambridge. He received the Polar Medal from Queen Elizabeth for his contributions to the study of glacier geophysics and the Gill Memorial Award from the Royal Geographical Society. He is chair of the Publications Committee of the International Glaciological Society and head of the Glaciers and Ice Sheets Division of the International Commission for Snow and Ice. Michael Hambrey is Director of the Centre for Glaciology at the University of Wales, Aberystwyth. A past recipient of the Polar Medal, he was also given the Earth Science Editors' Outstanding Publication Award for Glaciers (Cambridge University Press). Hambrey is also the author of Glacial Environments (British Columbia, 1994).

Arctic Amplification and Potential Mid-Latitude Weather Linkages

NASA Astrophysics Data System (ADS)

Overland, J. E.

2014-12-01

Increasing temperatures and other changes continued in the Arctic over the last decade, even though the rate of global warming has decreased in part due to a cool Pacific Ocean. Thus Arctic temperatures have increased at least 3 times the rate of mid-latitude temperatures. Credibility for persistent Arctic change comes from multiple indicators which are now available for multiple decades. Further, the spatial pattern of Arctic Amplification differs from patterns of natural variability. The role of the Arctic in the global climate system is based on multiple interacting feedbacks represented by these indicators as a causal basis for Arctic Amplification driven by modest global change. Many of these processes act on a regional basis and their non-linear interactions are not well captured by climate models. For example, future loss of sea ice due to increases in CO2 are demonstrated by these models but the rates of loss appear slow. It is reasonable to suspect that Arctic change which can produce the largest temperature anomalies on the planet and demonstrate recent extremes in the polar vortex could be linked to mid-latitude weather, especially as Arctic change will continue over the next decades. The meteorological community remains skeptical, however, in the sense of "not proven." Natural variability in chaotic atmospheric flow remains the main dynamic process, and it is difficult to determine whether Arctic forcing of a north-south linkage is emerging from the most recent period of Arctic change since 2007. Nonetheless, such a hypothesis is worthy of investigation, given the need to further understand Arctic dynamic atmospheric processes, and the potential for improving mid-latitude seasonal forecasts base on high-latitude forcing. Several AGU sessions and other forums over the next year (WWRP, IASC,CliC) address this issue, but the topic is not ready for a firm answer. The very level of controversy indicates the state of the science.

Evaluating Arctic warming mechanisms in CMIP5 models

NASA Astrophysics Data System (ADS)

Franzke, Christian L. E.; Lee, Sukyoung; Feldstein, Steven B.

2017-05-01

Arctic warming is one of the most striking signals of global warming. The Arctic is one of the fastest warming regions on Earth and constitutes, thus, a good test bed to evaluate the ability of climate models to reproduce the physics and dynamics involved in Arctic warming. Different physical and dynamical mechanisms have been proposed to explain Arctic amplification. These mechanisms include the surface albedo feedback and poleward sensible and latent heat transport processes. During the winter season when Arctic amplification is most pronounced, the first mechanism relies on an enhancement in upward surface heat flux, while the second mechanism does not. In these mechanisms, it has been proposed that downward infrared radiation (IR) plays a role to a varying degree. Here, we show that the current generation of CMIP5 climate models all reproduce Arctic warming and there are high pattern correlations—typically greater than 0.9—between the surface air temperature (SAT) trend and the downward IR trend. However, we find that there are two groups of CMIP5 models: one with small pattern correlations between the Arctic SAT trend and the surface vertical heat flux trend (Group 1), and the other with large correlations (Group 2) between the same two variables. The Group 1 models exhibit higher pattern correlations between Arctic SAT and 500 hPa geopotential height trends, than do the Group 2 models. These findings suggest that Arctic warming in Group 1 models is more closely related to changes in the large-scale atmospheric circulation, whereas in Group 2, the albedo feedback effect plays a more important role. Interestingly, while Group 1 models have a warm or weak bias in their Arctic SAT, Group 2 models show large cold biases. This stark difference in model bias leads us to hypothesize that for a given model, the dominant Arctic warming mechanism and trend may be dependent on the bias of the model mean state.

Relating Radiative Fluxes on Arctic Sea Ice Area Using Arctic Observation and Reanalysis Integrated System (ArORIS)

NASA Astrophysics Data System (ADS)

Sledd, A.; L'Ecuyer, T. S.

2017-12-01

With Arctic sea ice declining rapidly and Arctic temperatures rising faster than the rest of the globe, a better understanding of the Arctic climate, and ice cover-radiation feedbacks in particular, is needed. Here we present the Arctic Observation and Reanalysis Integrated System (ArORIS), a dataset of integrated products to facilitate studying the Arctic using satellite, reanalysis, and in-situ datasets. The data include cloud properties, radiative fluxes, aerosols, meteorology, precipitation, and surface properties, to name just a few. Each dataset has uniform grid-spacing, time-averaging and naming conventions for ease of use between products. One intended use of ArORIS is to assess Arctic radiation and moisture budgets. Following that goal, we use observations from ArORIS - CERES-EBAF radiative fluxes and NSIDC sea ice fraction and area to quantify relationships between the Arctic energy balance and surface properties. We find a discernable difference between energy budgets for years with high and low September sea ice areas. Surface fluxes are especially responsive to the September sea ice minimum in months both leading up to September and the months following. In particular, longwave fluxes at the surface show increased sensitivity in the months preceding September. Using a single-layer model of solar radiation we also investigate the individual responses of surface and planetary albedos to changes in sea ice area. By partitioning the planetary albedo into surface and atmospheric contributions, we find that the atmospheric contribution to planetary albedo is less sensitive to changes in sea ice area than the surface contribution. Further comparisons between observations and reanalyses can be made using the available datasets in ArORIS.

U.S. National Arctic Strategy: Preparing Defensive Lines of Effort for the Arctic

DTIC Science & Technology

2014-04-01

publications hint at new political posturing and suggest China should develop a more assertive approach to the international debates on controlling ...currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 01-04-2014 2. REPORT TYPE...importance of the Arctic, but lacks the infrastructure, command and control structure, and Arctic-capable assets to meet national strategic objectives

Levels and trends of contaminants in humans of the Arctic.

PubMed

Gibson, Jennifer; Adlard, Bryan; Olafsdottir, Kristin; Sandanger, Torkjel Manning; Odland, Jon Øyvind

2016-01-01

The Arctic Monitoring and Assessment Programme (AMAP) is one of the six working groups established under the Arctic Council. AMAP is tasked with monitoring the levels of contaminants present in the Arctic environment and people as well as assessing their effects on a continuous basis, and reporting these results regularly. Most of the presented data have been collected over the last 20 years and are from all eight Arctic countries. Levels of contaminants appear to be declining in some of the monitored Arctic populations, but it is not consistent across the Arctic. Most Arctic populations continue to experience elevated levels of these contaminants compared to other populations monitored globally. There are certain contaminants, such as perfluorinated compounds and polybrominated diphenyl ethers, which are still increasing in Arctic populations. These contaminants require more investigation to find out the predominant and important sources of exposure, and whether they are being transported to the Arctic through long-range transport in the environment.

Levels and trends of contaminants in humans of the Arctic

PubMed Central

Gibson, Jennifer; Adlard, Bryan; Olafsdottir, Kristin; Sandanger, Torkjel Manning; Odland, Jon Øyvind

2016-01-01

The Arctic Monitoring and Assessment Programme (AMAP) is one of the six working groups established under the Arctic Council. AMAP is tasked with monitoring the levels of contaminants present in the Arctic environment and people as well as assessing their effects on a continuous basis, and reporting these results regularly. Most of the presented data have been collected over the last 20 years and are from all eight Arctic countries. Levels of contaminants appear to be declining in some of the monitored Arctic populations, but it is not consistent across the Arctic. Most Arctic populations continue to experience elevated levels of these contaminants compared to other populations monitored globally. There are certain contaminants, such as perfluorinated compounds and polybrominated diphenyl ethers, which are still increasing in Arctic populations. These contaminants require more investigation to find out the predominant and important sources of exposure, and whether they are being transported to the Arctic through long-range transport in the environment. PMID:27974136

Observed Changes at the Surface of the Arctic Ocean

NASA Astrophysics Data System (ADS)

Ortmeyer, M.; Rigor, I.

2004-12-01

The Arctic has long been considered a harbinger of global climate change since simulations with global climate models predict that if the concentration of CO2 in the atmosphere doubles, the Arctic would warm by more than 5°C, compared to a warming of 2°C for subpolar regions (Manabe et al., 1991). And indeed, studies of the observational records show polar amplification of the warming trends (e.g. Serreze and Francis, 2004). These temperature trends are accompanied by myriad concurrent changes in Arctic climate. One of the first indicators of Arctic climate change was found by Walsh et al. (1996) using sea level pressure (SLP) data from the International Arctic Buoy Programme (IABP, http://iabp.apl.washington.edu). In this study, they showed that SLP over the Arctic Ocean decreased by over 4 hPa from 1979 - 1994. The decreases in SLP (winds) over the Arctic Ocean, forced changes in the circulation of sea ice and the surface ocean currents such that the Beaufort Gyre is reduced in size and speed (e.g. Rigor et al., 2002). Data from the IABP has also been assimilated into the global surface air temperature (SAT) climatologies (e.g. Jones et al. 1999), and the IABP SAT analysis shows that the temperature trends noted over land extend out over the Arctic Ocean. Specifically, Rigor et al. (2000) found warming trends in SAT over the Arctic Ocean during win¬ter and spring, with values as high as 2°C/decade in the eastern Arctic during spring. It should be noted that many of the changes in Arctic climate were first observed or explained using data from the IABP. The observations from IABP have been one of the cornerstones for environmental forecasting and studies of climate and climate change. These changes have a profound impact on wildlife and people. Many species and cultures depend on the sea ice for habitat and subsistence. Thus, monitoring the Arctic Ocean is crucial not only for our ability to detect climate change, but also to improve our understanding of the

Toward a United States Arctic research policy

NASA Astrophysics Data System (ADS)

Roederer, Juan G.

Of all countries bordering on the Arctic, the United States is the only one without a national institute, laboratory, or any other organization devoted to the sustained planning and support of Arctic research. Up to now, the responsibility for planning, implementing, and funding Arctic research has been divided between several federal agencies, the state of Alaska, and private groups whose mandates or objectives are often unconnected.The result of this pluralistic approach to U.S. science in the Arctic is that basic research has been conducted in piecemeal fashion. Individual studies are proposed and supported separately, and their costly logistic requirements must be funded in competition with research carried out under less-demanding environmental conditions in the rest of the country. Fundamental data-gathering and interpretation of information has been the responsibility of public agencies whose missions are separate and whose budgets may not reflect the priorities of Arctic issues.

An observational analysis: Tropical relative to Arctic influence on midlatitude weather in the era of Arctic amplification

NASA Astrophysics Data System (ADS)

Cohen, Judah

2016-05-01

The tropics, in general, and El Niño/Southern Oscillation (ENSO) in particular are almost exclusively relied upon for seasonal forecasting. Much less considered and certainly more controversial is the idea that Arctic variability is influencing midlatitude weather. However, since the late 1980s and early 1990s, the Arctic has undergone the most rapid warming observed globally, referred to as Arctic amplification (AA), which has coincided with an observed increase in extreme weather. Analysis of observed trends in hemispheric circulation over the period of AA more closely resembles variability associated with Arctic boundary forcings than with tropical forcing. Furthermore, analysis of intraseasonal temperature variability shows that the cooling in midlatitude winter temperatures has been accompanied by an increase in temperature variability and not a decrease, popularly referred to as "weather whiplash."

Arctic Ocean Paleoceanography and Future IODP Drilling

NASA Astrophysics Data System (ADS)

Stein, Ruediger

2015-04-01

Although the Arctic Ocean is a major player in the global climate/earth system, this region is one of the last major physiographic provinces on Earth where the short- and long-term geological history is still poorly known. This lack in knowledge is mainly due to the major technological/logistical problems in operating within the permanently ice-covered Arctic region which makes it difficult to retrieve long and undisturbed sediment cores. Prior to 2004, in the central Arctic Ocean piston and gravity coring was mainly restricted to obtaining near-surface sediments, i.e., only the upper 15 m could be sampled. Thus, all studies were restricted to the late Pliocene/Quaternary time interval, with a few exceptions. These include the four short cores obtained by gravity coring from drifting ice floes over the Alpha Ridge, where older pre-Neogene organic-carbon-rich muds and laminated biosiliceous oozes were sampled. Continuous central Arctic Ocean sedimentary records, allowing a development of chronologic sequences of climate and environmental change through Cenozoic times and a comparison with global climate records, however, were missing prior to the IODP Expedition 302 (Arctic Ocean Coring Expedition - ACEX), the first scientific drilling in the central Arctic Ocean. By studying the unique ACEX sequence, a large number of scientific discoveries that describe previously unknown Arctic paleoenvironments, were obtained during the last decade (for most recent review and references see Stein et al., 2014). While these results from ACEX were unprecedented, key questions related to the climate history of the Arctic Ocean remain unanswered, in part because of poor core recovery, and in part because of the possible presence of a major mid-Cenozoic hiatus or interval of starved sedimentation within the ACEX record. In order to fill this gap in knowledge, international, multidisciplinary expeditions and projects for scientific drilling/coring in the Arctic Ocean are needed. Key

The NSF Arctic Data Center: Leveraging the DataONE Federation to Build a Sustainable Archive for the NSF Arctic Research Community

NASA Astrophysics Data System (ADS)

Budden, A. E.; Arzayus, K. M.; Baker-Yeboah, S.; Casey, K. S.; Dozier, J.; Jones, C. S.; Jones, M. B.; Schildhauer, M.; Walker, L.

2016-12-01

The newly established NSF Arctic Data Center plays a critical support role in archiving and curating the data and software generated by Arctic researchers from diverse disciplines. The Arctic community, comprising Earth science, archaeology, geography, anthropology, and other social science researchers, are supported through data curation services and domain agnostic tools and infrastructure, ensuring data are accessible in the most transparent and usable way possible. This interoperability across diverse disciplines within the Arctic community facilitates collaborative research and is mirrored by interoperability between the Arctic Data Center infrastructure and other large scale cyberinfrastructure initiatives. The Arctic Data Center leverages the DataONE federation to standardize access to and replication of data and metadata to other repositories, specifically the NOAA's National Centers for Environmental Information (NCEI). This approach promotes long-term preservation of the data and metadata, as well as opening the door for other data repositories to leverage this replication infrastructure with NCEI and other DataONE member repositories. The Arctic Data Center uses rich, detailed metadata following widely recognized standards. Particularly, measurement-level and provenance metadata provide scientists the details necessary to integrate datasets across studies and across repositories while enabling a full understanding of the provenance of data used in the system. The Arctic Data Center gains this deep metadata and provenance support by simply adopting DataONE services, which results in significant efficiency gains by eliminating the need to develop systems de novo. Similarly, the advanced search tool developed by the Knowledge Network for Biocomplexity and extended for data submission by the Arctic Data Center, can be used by other DataONE-compliant repositories without further development. By standardizing interfaces and leveraging the DataONE federation

Production of Arctic Sea-ice Albedo by fusion of MISR and MODIS data

NASA Astrophysics Data System (ADS)

Kharbouche, Said; Muller, Jan-Peter

2017-04-01

We have combined data from the NASA MISR and MODIS spectro-radiometers to create a cloud-free albedo dataset specifically for sea-ice. The MISR (Multi-Angular Spectro-Radiometer) instrument on board Terra satellite has a unique ability to create high-quality Bidirectional Reflectance (BRF) over a 7 minute time interval per single overpass, thanks to its 9 cameras of different view angles (±70°,±60°,±45°,±26°). However, as MISR is limited to narrow spectral bands (443nm, 555nm, 670nm, 865nm), which is not sufficient to mask cloud effectively and robustly, we have used the sea-ice mask MOD09 product (Collection 6) from MODIS (Moderate resolution Imaging Spectoradiometer) instrument, which is also on board Terra satellite and acquiring data simultaneously. Only We have created a new and consistent sea-ice (for Arctic) albedo product that is daily, from 1st March to 22nd September for each and every year between 2000 to 2016 at two spatial grids, 1km x 1km and 5km x 5km in polar stereographic projection. Their analysis is described in a separate report [1]. References [1] Muller & Kharbouche, Variation of Arctic's Sea-ice Albedo between 2000 and 2016 by fusion of MISR and MODIS data. This conference. Acknowledgements This work was supported by www.QA4ECV.eu, a project of European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 607405. We thank our colleagues at JPL and NASA LaRC for processing these data, especially Sebastian Val and Steve Protack.

Airborne Lidar Measurements of Surface Topography and Structure in Arctic-Boreal Ecosystems

NASA Astrophysics Data System (ADS)

Hofton, M. A.; Blair, J. B.; Rabine, D.; Cornejo, H.; Story, S.

2017-12-01

In June-July 2017, NASA's Land, Vegetation and Ice Sensor (LVIS) Facility was deployed to sites in northern Canada and Alaska as part of NASA's Arctic-Boreal Vulnerability Experiment (ABoVE) 2017 airborne campaign. ABoVE is a large-scale, multi-year study of environmental change and its implications for social-ecological systems, and involves multiple airborne sensors flying both field-based and larger scale sampling sites. During the 4 week deployment of LVIS-F, a total of 15 flights were flown over diverse science targets based out of multiple airports in Canada and Alaska. LVIS-F is NASA's high-altitude airborne lidar sensor, collecting a nominal 2km wide swath of data from 10km altitude above the ground. Footprints are continguous both along and across track and for ABoVE operations, were 6m in diameter. Full waveform data are collected for every footprint and georeferenced to provide a true 3 dimensional view of overflown terrain. Along with precise positioning and pointing information, the LVIS laser range and waveform data are processed to provide high-quality measurements of surface structure including ground elevation, canopy height and canopy volume metrics. Information on data coverage and examples of level1b and level2 data products at science target sites will be shown along with initial results for data precision and accuracy. All AboVe LVIS data products will be available to investigators via a NASA DAAC.

Quantifying the Bering Strait Oceanic Fluxes and their Impacts on Sea-Ice and Water Properties in the Chukchi and Beaufort Seas and Western Arctic Ocean for 2013-2014

DTIC Science & Technology

2013-09-30

Right) Sea Surface Temperature (SST) MODIS/Aqua level 1 image from 26th August 2004 (courtesy of Ocean Color Data Processing Archive, NASA/Goddard Space...of Arctic bathymetry aids scientists and map makers, Eos Trans., 81(9), 89, 93, 96. Weingartner, T. J., S. Danielson, Y. Sasaki, V. Pavlov , and M

NASA Global Hawk: A New Tool for Earth Science Research

NASA Technical Reports Server (NTRS)

Hall, Phill

2009-01-01

This slide presentation reviews the Global Hawk, a unmanned aerial vehicle (UAV) that NASA plans to use for Earth Sciences research. The Global Hawk is the world's first fully autonomous high-altitude, long-endurance aircraft, and is capable of conducting long duration missions. Plans are being made for the use of the aircraft on missions in the Arctic, Pacific and Western Atlantic Oceans. There are slides showing the Global Hawk Operations Center (GHOC), Flight Control and Air Traffic Control Communications Architecture, and Payload Integration and Accommodations on the Global Hawk. The first science campaign, planned for a study of the Pacific Ocean, is reviewed.

The International Polar year 2007-2008; the Arctic human health legacy.

PubMed

Parkinson, Alan J

2007-01-01

Life expectancy in Arctic populations has greatly improved over the last 50 years. Much of this improvement can be attributed health research that has resulted in a reduction in morbidity and mortality from infectious diseases, such as tuberculosis, and the vaccine-preventable diseases of childhood. However, despite these improvements in health indicators of Arctic residents, life expectancy and infant mortality remain higher in indigenous Arctic residents in the US Arctic, northern Canada, and Greenland when compared to Arctic residents of Nordic countries. The International Polar Year (IPY) represents a unique opportunity to focus world attention on Arctic human health and to further stimulate Circumpolar cooperation on emerging Arctic human health concerns. The Arctic Human Health Initiative (AHHI) is an Arctic Council IPY initiative that aims to build and expand on existing Arctic Council and International Union for Circumpolar Health (IUCH) human health research activities. The human health legacy of the IPY will be increased visibility of the human health concerns of Arctic communities, revitalization of cooperative Arctic human health research focused on those concerns, the development of health policies based on research findings, and the subsequent implementation of appropriate interventions, prevention and control measures at the community level.

Arctic-HYCOS: a Large Sample observing system for estimating freshwater fluxes in the drainage basin of the Arctic Ocean

NASA Astrophysics Data System (ADS)

Pietroniro, Al; Korhonen, Johanna; Looser, Ulrich; Hardardóttir, Jórunn; Johnsrud, Morten; Vuglinsky, Valery; Gustafsson, David; Lins, Harry F.; Conaway, Jeffrey S.; Lammers, Richard; Stewart, Bruce; Abrate, Tommaso; Pilon, Paul; Sighomnou, Daniel; Arheimer, Berit

2015-04-01

The Arctic region is an important regulating component of the global climate system, and is also experiencing a considerable change during recent decades. More than 10% of world's river-runoff flows to the Arctic Ocean and there is evidence of changes in its fresh-water balance. However, about 30% of the Arctic basin is still ungauged, with differing monitoring practices and data availability from the countries in the region. A consistent system for monitoring and sharing of hydrological information throughout the Arctic region is thus of highest interest for further studies and monitoring of the freshwater flux to the Arctic Ocean. The purpose of the Arctic-HYCOS project is to allow for collection and sharing of hydrological data. Preliminary 616 stations were identified with long-term daily discharge data available, and around 250 of these already provide online available data in near real time. This large sample will be used in the following scientific analysis: 1) to evaluate freshwater flux to the Arctic Ocean and Seas, 2) to monitor changes and enhance understanding of the hydrological regime and 3) to estimate flows in ungauged regions and develop models for enhanced hydrological prediction in the Arctic region. The project is intended as a component of the WMO (World Meteorological Organization) WHYCOS (World Hydrological Cycle Observing System) initiative, covering the area of the expansive transnational Arctic basin with participation from Canada, Denmark, Finland, Iceland, Norway, Russian Federation, Sweden and United States of America. The overall objective is to regularly collect, manage and share high quality data from a defined basic network of hydrological stations in the Arctic basin. The project focus on collecting data on discharge and possibly sediment transport and temperature. Data should be provisional in near-real time if available, whereas time-series of historical data should be provided once quality assurance has been completed. The

Sulfate Aerosol in the Arctic: Source Attribution and Radiative Forcing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Yang; Wang, Hailong; Smith, Steven J.

Source attributions of Arctic sulfate and its direct radiative effect for 2010–2014 are quantified in this study using the Community Earth System Model (CESM) equipped with an explicit sulfur source-tagging technique. Regions that have high emissions and/or are near/within the Arctic present relatively large contributions to Arctic sulfate burden, with the largest contribution from sources in East Asia (27%). East Asia and South Asia together have the largest contributions to Arctic sulfate concentrations at 9–12 km, whereas sources within or near the Arctic account largely below 2 km. For remote sources with strong emissions, their contributions to Arctic sulfate burdenmore » are primarily driven by meteorology, while contributions of sources within or near the Arctic are dominated by their emission strength. The sulfate direct radiative effect (DRE) is –0.080 W m-2 at the Arctic surface, offsetting the net warming effect from the combination of in-snow heating and DRE cooling from black carbon. East Asia, Arctic local and Russia/Belarus/Ukraine sources contribute –0.017, –0.016 and –0.014 W m-2, respectively, to Arctic sulfate DRE. A 20% reduction in anthropogenic SO2 emissions leads to a net increase of +0.013 W m-2 forcing at the Arctic surface. These results indicate that a joint reduction in BC emissions could prevent possible Arctic warming from future reductions in SO2 emissions. Sulfate DRE efficiency calculations suggest that short transport pathways together with meteorology favoring long sulfate lifetimes make certain sources more efficient in influencing the Arctic sulfate DRE.« less

Climate Change, Globalization and Geopolitics in the New Maritime Arctic

NASA Astrophysics Data System (ADS)

Brigham, L. W.

2011-12-01

Early in the 21st century a confluence of climate change, globalization and geopolitics is shaping the future of the maritime Arctic. This nexus is also fostering greater linkage of the Arctic to the rest of the planet. Arctic sea ice is undergoing a historic transformation of thinning, extent reduction in all seasons, and reduction in the area of multiyear ice in the central Arctic Ocean. Global Climate Model simulations of Arctic sea ice indicate multiyear ice could disappear by 2030 for a short period of time each summer. These physical changes invite greater marine access, longer seasons of navigation, and potential, summer trans-Arctic voyages. As a result, enhanced marine safety, environmental protection, and maritime security measures are under development. Coupled with climate change as a key driver of regional change is the current and future integration of the Arctic's natural wealth with global markets (oil, gas and hard minerals). Abundant freshwater in the Arctic could also be a future commodity of value. Recent events such as drilling for hydrocarbons off Greenland's west coast and the summer marine transport of natural resources from the Russian Arctic to China across the top of Eurasia are indicators of greater global economic ties to the Arctic. Plausible Arctic futures indicate continued integration with global issues and increased complexity of a range of regional economic, security and environmental challenges.

Arctic-like Rabies Virus, Bangladesh

PubMed Central

Jamil, Khondoker Mahbuba; Hossain, Moazzem; Matsumoto, Takashi; Ali, Mohammad Azmat; Hossain, Sohrab; Hossain, Shakhawat; Islam, Aminul; Nasiruddin, Mohammad; Nishizono, Akira

2012-01-01

Arctic/Arctic-like rabies virus group 2 spread into Bangladesh ≈32 years ago. Because rabies is endemic to and a major public health problem in this country, we characterized this virus group. Its glycoprotein has 3 potential N-glycosylation sites that affect viral pathogenesis. Diversity of rabies virus might have public health implications in Bangladesh. PMID:23171512

Arctic Council Nations Could Encourage Development of Climate Indicator: Flux to the Atmosphere from Arctic Permafrost Carbon

NASA Astrophysics Data System (ADS)

Ekwurzel, B.; Yona, L.; Natali, S.; Holmes, R. M.; Schuur, E.

2015-12-01

Permafrost regions store almost twice the carbon in the atmosphere (Tarnocai et al 2009). As climate warms a proportion of this carbon will be released as carbon dioxide and methane. The Arctic Council may be best suited to harness international scientific collaboration for policy relevant knowledge about the global impacts of permafrost thaw. Scientists in Arctic Council and observer states have historically collaborated on permafrost research (e.g. Permafrost Carbon Network, part of Study of Environmental Arctic Change (SEARCH) project). This work increased knowledge of permafrost carbon pool size and vulnerability. However, data gaps persist across the Arctic. Despite gaps, numerous studies directly inform international policy negotiations aiming to stay below 2° C. Some suggest "permafrost carbon feedback" may comprise 3 to 11% of total allowed emissions through 2100 under a RCP4.5 (Schaefer et al2014). Understanding and accounting for future permafrost atmospheric carbon release requires science and policy coordination that the Arctic Council could incentivize. For example, Council nations could convene scientists and stakeholders to develop a Permafrost-Climate Indicator providing more direct decision support than current permafrost indicators, and identify research needed for a periodic estimate of Arctic permafrost CO2 and CH4 emissions. This presentation covers current challenges scientists and policymakers may face to develop a practical and robust Permafrost Climate Indicator. For example, which timescales are most appropriate for international emissions commitments? Do policy-relevant timescales align with current scientific knowledge? What are the uncertainties and how can they be decreased? We present likely strengths and challenges of a Permafrost Climate Indicator co-developed by scientists and stakeholders. Potential greenhouse gas atmospheric flux from Arctic permafrost carbon may be greater than some nations' United Nations emissions reductions

Arctic-midlatitude weather linkages in North America

NASA Astrophysics Data System (ADS)

Overland, James E.; Wang, Muyin

2018-06-01

There is intense public interest in whether major Arctic changes can and will impact midlatitude weather such as cold air outbreaks on the central and east side of continents. Although there is progress in linkage research for eastern Asia, a clear gap is conformation for North America. We show two stationary temperature/geopotential height patterns where warmer Arctic temperatures have reinforced existing tropospheric jet stream wave amplitudes over North America: a Greenland/Baffin Block pattern during December 2010 and an Alaska Ridge pattern during December 2017. Even with continuing Arctic warming over the past decade, other recent eastern US winter months were less susceptible for an Arctic linkage: the jet stream was represented by either zonal flow, progressive weather systems, or unfavorable phasing of the long wave pattern. The present analysis lays the scientific controversy over the validity of linkages to the inherent intermittency of jet stream dynamics, which provides only an occasional bridge between Arctic thermodynamic forcing and extended midlatitude weather events.

Arctic Clouds

Atmospheric Science Data Center

2013-04-19

...     View Larger Image Stratus clouds are common in the Arctic during the summer months, ... (Acro Service Corporation/Jet Propulsion Laboratory), David J. Diner (Jet Propulsion Laboratory). Other formats available at JPL ...

Coarse mode aerosols in the High Arctic

NASA Astrophysics Data System (ADS)

Baibakov, K.; O'Neill, N. T.; Chaubey, J. P.; Saha, A.; Duck, T. J.; Eloranta, E. W.

2014-12-01

Fine mode (submicron) aerosols in the Arctic have received a fair amount of scientific attention in terms of smoke intrusions during the polar summer and Arctic haze pollution during the polar winter. Relatively little is known about coarse mode (supermicron) aerosols, notably dust, volcanic ash and sea salt. Asian dust is a regular springtime event whose optical and radiative forcing effects have been fairly well documented at the lower latitudes over North America but rarely reported for the Arctic. Volcanic ash, whose socio-economic importance has grown dramatically since the fear of its effects on aircraft engines resulted in the virtual shutdown of European civil aviation in the spring of 2010 has rarely been reported in the Arctic in spite of the likely probability that ash from Iceland and the Aleutian Islands makes its way into the Arctic and possibly the high Arctic. Little is known about Arctic sea salt aerosols and we are not aware of any literature on the optical measurement of these aerosols. In this work we present preliminary results of the combined sunphotometry-lidar analysis at two High Arctic stations in North America: PEARL (80°N, 86°W) for 2007-2011 and Barrow (71°N,156°W) for 2011-2014. The multi-years datasets were analyzed to single out potential coarse mode incursions and study their optical characteristics. In particular, CIMEL sunphotometers provided coarse mode optical depths as well as information on particle size and refractive index. Lidar measurements from High Spectral Resolution lidars (AHSRL at PEARL and NSHSRL at Barrow) yielded vertically resolved aerosol profiles and gave an indication of particle shape and size from the depolarization ratio and color ratio profiles. Additionally, we employed supplementary analyses of HYSPLIT backtrajectories, OMI aerosol index, and NAAPS (Navy Aerosol Analysis and Prediction System) outputs to study the spatial context of given events.

Arctic Change Detection: Multiple Observations and Recent Explanations

NASA Astrophysics Data System (ADS)

Soreide, N. N.; Overland, J. E.; Calder, J.

2004-12-01

The recently released Arctic Climate Impact Assessment (ACIA) Report documents Arctic-wide changes and impacts; it provides a long-term perspective for peoples, governments and scientists in coping with these changes. Further, investigation of the last three decades of multivariate biophysical data sets(climate, land and marine ecosystems, cryosphere) and century-long weather records, show two main types of Arctic variability. These are: 1) long-term trends as represented by loss of sea-ice and tundra area and their biological response, and 2) decadal variability in atmospheric forcing and its direct impacts. Three main conclusions are possible: * Temperature anomalies in the last 15 years are unique in the Arctic instrumental record (1880-2003). Historically, there were regional/decadal warm events during winter and spring in the 1930s to 1950s, but meteorological analysis shows that these surface air temperature anomalies are the result of intrinsic variability in regional flow patterns, as contrasted with the Arctic-wide Arctic Oscillation (AO) influence of the 1990s. * These changes are primarily driven by changes in atmospheric circulation, and thus are subject to north/south gradients in hemispheric radiative forcing from volcanic aerosols, insolation cycles and CO2 increase. These north/south differences drive temperature advection in the trough-ridge structure of the AO. This conclusion is based primarily on model results and impacts from volcanos. * Change is likely to be irreversible over at least the next decade. In the previous five years, many ecosystems, such as the Bering Sea and east Greenland, are showing more year-to-year persistence, despite considerable variability in the AO and other climate indices. We hypothesize that the changes occurring in the Arctic are beginning to be significant enough to make the Arctic less sensitive to cold swings in atmospheric variability, although direct mechanisms are unclear. A next step in the post-ACIA period

Characterizing Arctic sea ice topography and atmospheric form drag using high-resolution IceBridge data

NASA Astrophysics Data System (ADS)

Petty, A.; Tsamados, M.; Kurtz, N. T.; Farrell, S. L.; Newman, T.; Harbeck, J.; Feltham, D. L.; Richter-Menge, J.

2015-12-01

Here we present a detailed analysis of Arctic sea ice topography using high resolution, three-dimensional surface elevation data from the NASA Operation IceBridge Airborne Topographic Mapper (ATM) laser altimeter. We derive novel ice topography statistics from 2009-2014 across both first-year and multiyear ice regimes - including the height, area coverage, orientation and spacing of distinct surface features. The sea ice topography exhibits strong spatial variability, including increased surface feature (e.g. pressure ridge) height and area coverage within the multi-year ice regions. The ice topography also shows a strong coastal dependency, with the feature height and area coverage increasing as a function of proximity to the nearest coastline, especially north of Greenland and the Canadian Archipelago. The ice topography data have also been used to explicitly calculate atmospheric drag coefficients over Arctic sea ice; utilizing existing relationships regarding ridge geometry and their impact on form drag. The results are being used to calibrate the recent drag parameterization scheme included in the sea ice model CICE.

Climate Change: Science and Policy in the Arctic Climate Change: Science and Policy in the Arctic

NASA Astrophysics Data System (ADS)

Bigras, S. C.

2009-12-01

It is an accepted fact that the Earth’s climate is warming. Recent research has demonstrated the direct links between the Arctic regions and the rest of the planet. We have become more aware that these regions are feeling the effects of global climate change more intensely than anywhere else on Earth -- and that they are fast becoming the new frontiers for resources and political disputes. This paper examines some of the potential climate change impacts in the Arctic and how the science of climate change can be used to develop policies that will help mitigate some of these impacts. Despite the growing body of research we do not yet completely understand the potential consequences of climate change in the Arctic. Climate models predict significant changes and impacts on the northern physical environment and renewable resources, and on the communities and societies that depend on them. Policies developed and implemented as a result of the research findings will be designed to help mitigate some of the more serious consequences. Given the importance of cost in making policy decisions, the financial implications of different scenarios will need to be considered. The Arctic Ocean Basin is a complex and diverse environment shared by five Arctic states. Cooperation among the states surrounding the Arctic Ocean is often difficult, as each country has its own political and social agenda. Northerners and indigenous peoples should be engaged and able to influence the direction of northern adaptation policies. Along with climate change, the Arctic environment and Arctic residents face many other challenges, among them safe resource development. Resource development in the Arctic has always been a controversial issue, seen by some as a solution to high unemployment and by others as an unacceptably disruptive and destructive force. Its inherent risks need to be considered: there are needs for adaptation, for management frameworks, for addressing cumulative effects, and for

Polycyclic aromatic hydrocarbon-DNA adducts in Beluga whales from the Arctic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mathieu, A.; Payne, J.F.; Fancey, L.L.

1997-09-01

The Arctic is still relatively pristine in nature, but it is also vulnerable to pollution because contaminants originating from midlatitudes are transported to the Arctic by atmospheric processes, ocean currents, and river. Recognition of this fact of Arctic vulnerability has resulted in a Declaration on the Protection of the Arctic Environment by eight Arctic countries. A manifest aim of this declaration is to develop an Arctic Monitoring and Assessment Program. We report here on the presence of measurable levels of polycyclic aromatic hydrocarbon-DNA adducts, including relatively high levels in Arctic beluga (Delphinapterus leucas). These results lend support to the valuemore » of developing biological assessment programs for Arctic wildlife. 15 refs., 1 tab.« less

Emissions of Black Carbon, Organic, and Inorganic Aerosols From Biomass Burning in North America and Asia in 2008

NASA Technical Reports Server (NTRS)

Kondo, Y.; Matsui, H.; Moteki, N.; Sahu, L.; Takegawa, N.; Kajino, M.; Zhao, Y.; Cubison, M. J.; Jimenez, J. L.; Vay, S.;

Satellite Observed Changes in the Arctic

NASA Technical Reports Server (NTRS)

Comiso, Josefino C.; Parkinson, Claire L.

2004-01-01

The Arctic is currently considered an area in transformation. Glaciers have been retreating, permafrost has been diminishing, snow covered areas have been decreasing, and sea ice and ice sheets have been thinning. This paper provides an overview of the unique role that satellite sensors have contributed in the detection of changes in the Arctic and demonstrates that many of the changes are not just local but a pan-Arctic phenomenon. Changes from the upper atmosphere to the surface are discussed and it is apparent that the magnitude of the trends tends to vary from region to region and from season to season. Previous reports of a warming Arctic and a retreating perennial ice cover have also been updated, and results show that changes are ongoing. Feedback effects that can lead to amplification of the signals and the role of satellite data in enhancing global circulation models are also discussed.

Arctic Climate and Atmospheric Planetary Waves

NASA Technical Reports Server (NTRS)

Cavalieri, D. J.; Haekkinen, S.

2000-01-01

Analysis of a fifty-year record (1946-1995) of monthly-averaged sea level pressure data provides a link between the phases of planetary-scale sea level pressure waves and Arctic Ocean and ice variability. Results of this analysis show: (1) a breakdown of the dominant wave I pattern in the late 1960's, (2) shifts in the mean phase of waves 1 and 2 since this breakdown, (3) an eastward shift in the phases of both waves 1 and 2 during the years of simulated cyclonic Arctic Ocean circulation relative to their phases during the years of anticyclonic circulation, (4) a strong decadal variability of wave phase associated with simulated Arctic Ocean circulation changes. Finally, the Arctic atmospheric circulation patterns that emerge when waves 1 and 2 are in their extreme eastern and western positions suggest an alternative approach to determine significant forcing patterns of sea ice and high-latitude variability.

Seeing the risks of multiple Arctic amplifying feedbacks.

NASA Astrophysics Data System (ADS)

Carter, P.

2014-12-01

There are several potentially very large sources of Arctic amplifying feedbacks that have been identified. They present a great risk to the future as they could become self and inter-reinforcing with uncontrollable knock-on, or cascading risks. This has been called a domino effect risk by Carlos Duarte. Because of already committed global warming and the millennial duration of global warming, these are highly policy relevant. These Arctic feedback processes are now all operant with emissions of carbon dioxide methane and nitrous oxide detected. The extent of the risks from these feedback sources are not obvious or easy to understand by policy makers and the public. They are recorded in the IPCC AR5 as potential tipping points, as is the irreversibility of permafrost thaw. Some of them are not accounted for in the IPCC AR5 global warming projections because of quantitative uncertainty. UNEP issued a 2012 report (Policy Implications of Thawing Permafrost) advising that by omitting carbon feedback emissions from permafrost, carbon budget calculations by err on the low side. There is the other unassessed issue of a global warming safety limit for preventing uncontrollable increasing Arctic feedback emissions. Along with our paper, we provide illustrations of the Arctic feedback sources and processes from satellite imagery and flow charts that allows for their qualitative consideration. We rely on the IPCC assessments, the 2012 paper Possible role of wetlands permafrost can methane hydrates in the methane cycle under future climate change; a review, by Fiona M. O'Connor et al., and build on the WWF 2009 Arctic Climate Feedbacks: Global Implications. The potential sources of Arctic feedback processes identified include: Arctic and Far North snow albedo decline, Arctic summer sea ice albedo decline, Greenland summer ice surface melting albedo loss, albedo decline by replacement of Arctic tundra with forest, tundra fires, Boreal forest fires, Boreal forest die

A quantitative assessment of Arctic shipping in 2010–2014

PubMed Central

Eguíluz, Victor M.; Fernández-Gracia, Juan; Irigoien, Xabier; Duarte, Carlos M.

2016-01-01

Rapid loss of sea ice is opening up the Arctic Ocean to shipping, a practice that is forecasted to increase rapidly by 2050 when many models predict that the Arctic Ocean will largely be free of ice toward the end of summer. These forecasts carry considerable uncertainty because Arctic shipping was previously considered too sparse to allow for adequate validation. Here, we provide quantitative evidence that the extent of Arctic shipping in the period 2011–2014 is already significant and that it is concentrated (i) in the Norwegian and Barents Seas, and (ii) predominantly accessed via the Northeast and Northwest Passages. Thick ice along the forecasted direct trans-Arctic route was still present in 2014, preventing transit. Although Arctic shipping remains constrained by the extent of ice coverage, during every September, this coverage is at a minimum, allowing the highest levels of shipping activity. Access to Arctic resources, particularly fisheries, is the most important driver of Arctic shipping thus far. PMID:27477878

Variability of the Arctic Basin Oceanographic Fields

DTIC Science & Technology

1996-02-01

the model a very sophisticated turbulence closure scheme. 9. Imitation of the CO2 doubling We parameterized the " greenhouse " effect by changing the...of the Arctic Ocean. A more realistic model of the Arctic Ocean circulation was obtained, and an estimation of the impact of the greenhouse effect on... greenhouse effect is in freshening of the upper Arctic Basin. Although some shortcomings of the model still exist (an unrealistic high coefficient of

Proceedings of the Conference Arctic '85; Civil Engineering in the Artic offshore

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bennett, F.L.; Machemehl, J.L.

1985-01-01

Topics of the 1985 Conference included: Arctic construction, Arctic foundation, Arctic structures, and ocean effects. Arctic terminals and coastal offshore bases, protecting the Arctic environment, and probabilistic methods in Arctic offshore engineering were also discussed. Ice mechanics, marine pipelines in the Arctic, and the role of universities in training civil engineers for Arctic offshore development were highlighted. Sessions on remote sensing, surveying, and mapping were included, and offshore installations in the Bering Sea were discussed. Another topic of discussion was research in Civil Engineering for development of the Arctic offshore. The overall thrust of the conference was the application ofmore » Arctic offshore engineering principles and research in the field of oil and gas exploration and exploitation activity.« less

Estimation of Arctic Sea Ice Freeboard and Thickness Using CryoSat-2

NASA Astrophysics Data System (ADS)

Lee, Sanggyun; Im, Jungho; yoon, Hyeonjin; Shin, Minso; Kim, Miae

2014-05-01

Arctic sea ice is one of the significant components of the global climate system as it plays a significant role in driving global ocean circulation, provides a continuous insulating layer at air-sea interface, and reflects a large portion of the incoming solar radiation in Polar Regions. Sea ice extent has constantly declined since 1980s. Its area was the lowest ever recorded on 16 September 2012 since the satellite record began in 1979. Arctic sea ice thickness has also been diminishing along with the decreasing sea ice extent. Because extent and thickness, two main characteristics of sea ice, are important indicators of the polar response to on-going climate change, there has been a great effort to quantify them using various approaches. Sea ice thickness has been measured with numerous field techniques such as surface drilling and deploying buoys. These techniques provide sparse and discontinuous data in spatiotemporal domain. Spaceborne radar and laser altimeters can overcome these limitations and have been used to estimate sea ice thickness. Ice Cloud and land Elevation Satellite (ICEsat), a laser altimeter from National Aeronautics and Space Administration (NASA), provided data to detect polar area elevation change between 2003 and 2009. CryoSat-2 launched with Synthetic Aperture Radar (SAR)/Interferometric Radar Altimeter (SIRAL) on April 2010 can provide data to estimate time-series of Arctic sea ice thickness. In this study, Arctic sea ice freeboard and thickness in 2012 and 2013 were estimated using CryoSat-2 SAR mode data that has sea ice surface height relative to the reference ellipsoid WGS84. In order to estimate sea ice thickness, freeboard height, elevation difference between the top of sea ice surface and leads should be calculated. CryoSat-2 profiles such as pulse peakiness, backscatter sigma-0, number of echoes, and significant wave height were examined to distinguish leads from sea ice. Several near-real time cloud-free MODIS images as CryoSat-2

Arctic shipping emissions inventories and future scenarios

NASA Astrophysics Data System (ADS)

Corbett, J. J.; Lack, D. A.; Winebrake, J. J.; Harder, S.; Silberman, J. A.; Gold, M.

2010-04-01

The Arctic is a sensitive region in terms of climate change and a rich natural resource for global economic activity. Arctic shipping is an important contributor to the region's anthropogenic air emissions, including black carbon - a short-lived climate forcing pollutant especially effective in accelerating the melting of ice and snow. These emissions are projected to increase as declining sea ice coverage due to climate change allows for increased shipping activity in the Arctic. To understand the impacts of these increased emissions, scientists and modelers require high-resolution, geospatial emissions inventories that can be used for regional assessment modeling. This paper presents 5 km×5 km Arctic emissions inventories of important greenhouse gases, black carbon and other pollutants under existing and future (2050) scenarios that account for growth of shipping in the region, potential diversion traffic through emerging routes, and possible emissions control measures. Short-lived forcing of ~4.5 gigagrams of black carbon from Arctic shipping may increase climate forcing; a first-order calculation of global warming potential due to 2030 emissions in the high-growth scenario suggests that short-lived forcing of ~4.5 gigagrams of black carbon from Arctic shipping may increase climate forcing due to Arctic ships by at least 17% compared to warming from these vessels' CO2 emissions (~42 000 gigagrams). The paper also presents maximum feasible reduction scenarios for black carbon in particular. These emissions reduction scenarios will enable scientists and policymakers to evaluate the efficacy and benefits of technological controls for black carbon, and other pollutants from ships.

Polar Gateways Arctic Circle Sunrise Conference 2008, Barrow, Alaska: IHY-IPY Outreach on Exploration of Polar and Icy Worlds in The Solar System

NASA Astrophysics Data System (ADS)

Cooper, John F.; Kauristie, K.; Weatherwax, A. T.; Sheehan, G. W.; Smith, R. W.; Sandahl, I.; Østgaard, N.; Chernouss, S.; Moore, M. H.; Peticolas, L. M.; Senske, D. A.; Thompson, B. J.; Tamppari, L. K.; Lewis, E. M.

2008-09-01

Polar, heliophysical, and planetary science topics related to the International Heliophysical and Polar Years 2007-2009 were addressed during this circumpolar video conference hosted January 23-29, 2008 at the new Barrow Arctic Research Center of the Barrow Arctic Science Consortium in Barrow, Alaska. This conference was planned as an IHY-IPY event science outreach event bringing together scientists and educational specialists for the first week of sunrise at subzero Arctic temperatures in Barrow. Science presentations spanned the solar system from the polar Sun to Earth, Moon, Mars, Jupiter, Saturn, and the Kuiper Belt. On-site participants experienced look and feel of icy worlds like Europa and Titan by being in the Barrow tundra and sea ice environment and by going "on the ice" during snowmobile expeditions to the near-shore sea ice environment and to Point Barrow, closest geographic point in the U.S. to the North Pole. Many science presentations were made remotely via video conference or teleconference from Sweden, Norway, Russia, Canada, Antarctica, and the United States, spanning up to thirteen time zones (Alaska to Russia) at various times. Extensive educational outreach activities were conducted with the local Barrow and Alaska North Slope communities and through the NASA Digital Learning Network live from the "top of the world" at Barrow. The Sun-Earth Day team from Goddard, and a videographer from the Passport to Knowledge project, carried out extensive educational interviews with many participants and native Inupiaq Eskimo residents of Barrow. Video and podcast recordings of selected interviews are available at http://sunearthday.nasa.gov/2008/multimedia/podcasts.php. Excerpts from these and other interviews will be included in a new high definition video documentary called "From the Sun to the Stars: The New Science of Heliophysics" from Passport to Knowledge that will later broadcast on NASA TV and other educational networks. Full conference

Polar Gateways Arctic Circle Sunrise Conference 2008, Barrow, Alaska: IHY-IPY Outreach on Exploration of Polar and Icy Worlds in the Solar System

NASA Technical Reports Server (NTRS)

Cooper, John F.; Kauristie, Kirsti; Weatherwax, Allan T.; Sheehan, Glenn W.; Smith, Roger W.; Sandahl, Ingrid; Ostgaard, Nikolai; Chernouss, Sergey; Thompson, Barbara J.; Peticolas, Laura;

Rabies in the arctic fox population, Svalbard, Norway.

PubMed

Mørk, Torill; Bohlin, Jon; Fuglei, Eva; Åsbakk, Kjetil; Tryland, Morten

2011-10-01

Arctic foxes, 620 that were trapped and 22 found dead on Svalbard, Norway (1996-2004), as well as 10 foxes trapped in Nenets, North-West Russia (1999), were tested for rabies virus antigen in brain tissue by standard direct fluorescent antibody test. Rabies antigen was found in two foxes from Svalbard and in three from Russia. Blood samples from 515 of the fox carcasses were screened for rabies antibodies with negative result. Our results, together with a previous screening (1980-1989, n=817) indicate that the prevalence of rabies in Svalbard has remained low or that the virus has not been enzootic in the arctic fox population since the first reported outbreak in 1980. Brain tissues from four arctic foxes (one from Svalbard, three from Russia) in which rabies virus antigen was detected were further analyzed by reverse-transcriptase polymerase chain reaction direct amplicon sequencing and phylogenetic analysis. Sequences were compared to corresponding sequences from rabies virus isolates from other arctic regions. The Svalbard isolate and two of the Russian isolates were identical (310 nucleotides), whereas the third Russian isolate differed in six nucleotide positions. However, when translated into amino acid sequences, none of these substitutions produced changes in the amino acid sequence. These findings suggest that the spread of rabies virus to Svalbard was likely due to migration of arctic foxes over sea ice from Russia to Svalbard. Furthermore, when compared to other Arctic rabies virus isolates, a high degree of homology was found, suggesting a high contact rate between arctic fox populations from different arctic regions. The high degree of homology also indicates that other, and more variable, regions of the genome than this part of the nucleoprotein gene should be used to distinguish Arctic rabies virus isolates for epidemiologic purposes.

Amplified Arctic warming by phytoplankton under greenhouse warming.

PubMed

Park, Jong-Yeon; Kug, Jong-Seong; Bader, Jürgen; Rolph, Rebecca; Kwon, Minho

2015-05-12

Phytoplankton have attracted increasing attention in climate science due to their impacts on climate systems. A new generation of climate models can now provide estimates of future climate change, considering the biological feedbacks through the development of the coupled physical-ecosystem model. Here we present the geophysical impact of phytoplankton, which is often overlooked in future climate projections. A suite of future warming experiments using a fully coupled ocean-atmosphere model that interacts with a marine ecosystem model reveals that the future phytoplankton change influenced by greenhouse warming can amplify Arctic surface warming considerably. The warming-induced sea ice melting and the corresponding increase in shortwave radiation penetrating into the ocean both result in a longer phytoplankton growing season in the Arctic. In turn, the increase in Arctic phytoplankton warms the ocean surface layer through direct biological heating, triggering additional positive feedbacks in the Arctic, and consequently intensifying the Arctic warming further. Our results establish the presence of marine phytoplankton as an important potential driver of the future Arctic climate changes.

Amplified Arctic warming by phytoplankton under greenhouse warming

PubMed Central

Park, Jong-Yeon; Kug, Jong-Seong; Bader, Jürgen; Rolph, Rebecca; Kwon, Minho

2015-01-01

Phytoplankton have attracted increasing attention in climate science due to their impacts on climate systems. A new generation of climate models can now provide estimates of future climate change, considering the biological feedbacks through the development of the coupled physical–ecosystem model. Here we present the geophysical impact of phytoplankton, which is often overlooked in future climate projections. A suite of future warming experiments using a fully coupled ocean−atmosphere model that interacts with a marine ecosystem model reveals that the future phytoplankton change influenced by greenhouse warming can amplify Arctic surface warming considerably. The warming-induced sea ice melting and the corresponding increase in shortwave radiation penetrating into the ocean both result in a longer phytoplankton growing season in the Arctic. In turn, the increase in Arctic phytoplankton warms the ocean surface layer through direct biological heating, triggering additional positive feedbacks in the Arctic, and consequently intensifying the Arctic warming further. Our results establish the presence of marine phytoplankton as an important potential driver of the future Arctic climate changes. PMID:25902494

Arctic plant diversity in the Early Eocene greenhouse

PubMed Central

Harrington, Guy J.; Eberle, Jaelyn; Le-Page, Ben A.; Dawson, Mary; Hutchison, J. Howard

2012-01-01

For the majority of the Early Caenozoic, a remarkable expanse of humid, mesothermal to temperate forests spread across Northern Polar regions that now contain specialized plant and animal communities adapted to life in extreme environments. Little is known on the taxonomic diversity of Arctic floras during greenhouse periods of the Caenozoic. We show for the first time that plant richness in the globally warm Early Eocene (approx. 55–52 Myr) in the Canadian High Arctic (76° N) is comparable with that approximately 3500 km further south at mid-latitudes in the US western interior (44–47° N). Arctic Eocene pollen floras are most comparable in richness with today's forests in the southeastern United States, some 5000 km further south of the Arctic. Nearly half of the Eocene, Arctic plant taxa are endemic and the richness of pollen floras implies significant patchiness to the vegetation type and clear regional richness of angiosperms. The reduced latitudinal diversity gradient in Early Eocene North American plant species demonstrates that extreme photoperiod in the Arctic did not limit taxonomic diversity of plants. PMID:22072610

Arctic Freshwater Synthesis: Summary of key emerging issues

NASA Astrophysics Data System (ADS)

Prowse, T.; Bring, A.; Mârd, J.; Carmack, E.; Holland, M.; Instanes, A.; Vihma, T.; Wrona, F. J.

2015-10-01

In response to a joint request from the World Climate Research Program's Climate and Cryosphere Project, the International Arctic Science Committee, and the Arctic Council's Arctic Monitoring and Assessment Program an updated scientific assessment has been conducted of the Arctic Freshwater System (AFS), entitled the Arctic Freshwater Synthesis (AFSΣ). The major reason behind the joint request was an increasing concern that changes to the AFS have produced, and could produce even greater, changes to biogeophysical and socioeconomic systems of special importance to northern residents and also produce extra-Arctic climatic effects that will have global consequences. The AFSΣ was structured around six key thematic areas: atmosphere, oceans, terrestrial hydrology, terrestrial ecology, resources, and modeling, the review of each coauthored by an international group of scientists and published as separate manuscripts in this special issue of Journal of Geophysical Research-Biogeosciences. This AFSΣ summary manuscript reviews key issues that emerged during the conduct of the synthesis, especially those that are cross-thematic in nature, and identifies future research required to address such issues.

A 10-year Retrospective of NASA's Contribution to NEESPI Science: What we Have Learned on Climate-Ecosystem-Society Interactions in Northern Eurasia

NASA Astrophysics Data System (ADS)

Gutman, G.; Groisman, P. Y.

2015-12-01

The Northern Eurasia Earth Science Partnership Initiative (NEESPI) has produced over 1500 scientific papers based on 170+ projects with international teams from over 200 institutions in 30 countries. This overview will provide a summary of the achievements in the NASA component of this large international initiative during the last 10 years. It will cover various NEESPI sectors, including the Arctic, the boreal systems of Siberia and Far East, the dry lands of Central Asia and ecosystems of Eastern Europe. The emphasis will be made on what we have learned from the NEESPI studies supported by the NASA Land-Cover/Land- Use Change Program. It will include examples of forest and agricultural changes, implications to carbon and hydrologic cycles, changes in environmental pollution, urban changes and impacts on society. The presentation will illustrate land-use changes during the last couple of decades and describe impacts of land-use change in the Arctic, where land use practiced by indigenous people is giving way to intensive exploitation of the land for commercial and industrial uses. Fields abandonment and more recent returning agricultural practices in mid-latitudes will also be discussed. The presentation will be based on the results from the NEESPI Synthesis projects supported by the NASA LCLUC program and the material described in the books published by international NEESPI teams.

Climate change, future Arctic Sea ice, and the competitiveness of European Arctic offshore oil and gas production on world markets.

PubMed

Petrick, Sebastian; Riemann-Campe, Kathrin; Hoog, Sven; Growitsch, Christian; Schwind, Hannah; Gerdes, Rüdiger; Rehdanz, Katrin

2017-12-01

A significant share of the world's undiscovered oil and natural gas resources are assumed to lie under the seabed of the Arctic Ocean. Up until now, the exploitation of the resources especially under the European Arctic has largely been prevented by the challenges posed by sea ice coverage, harsh weather conditions, darkness, remoteness of the fields, and lack of infrastructure. Gradual warming has, however, improved the accessibility of the Arctic Ocean. We show for the most resource-abundant European Arctic Seas whether and how a climate induced reduction in sea ice might impact future accessibility of offshore natural gas and crude oil resources. Based on this analysis we show for a number of illustrative but representative locations which technology options exist based on a cost-minimization assessment. We find that under current hydrocarbon prices, oil and gas from the European offshore Arctic is not competitive on world markets.

Concentrations of selected essential and non-essential elements in arctic fox (Alopex lagopus) and wolverines (Gulo gulo) from the Canadian Arctic.

PubMed

Hoekstra, P F; Braune, B M; Elkin, B; Armstrong, F A J; Muir, D C G

2003-06-20

Arctic fox (Alopex lagopus) and wolverine (Gulo gulo) tissues were collected in the Canadian Arctic from 1998 to 2001 and analyzed for various essential and non-essential elements. Several elements (Ag, Al, As, B, Ba, Be, Co, Cr, Mo, Ni, Sb, Sn, Sr, Tl, U and V) were near or below the detection limits in >95% arctic fox and wolverine samples. Concentrations of Cd, Cu, Fe, total Hg (THg), Mn, Pb, Se and Zn were quantifiable in >50% of the samples analyzed and reported herein. Hepatic elemental concentrations were not significantly different among arctic foxes collected at Ulukhaqtuuq (Holman), NT (n=13) and Arviat, NU (n=50), but were significantly greater than concentrations found in wolverine liver from Kugluktuk (Coppermine), NU (n=12). The mean (+/-1 S.E.) concentrations of Cd in kidney were also significantly greater in arctic fox (1.08+/-0.19 microg g(-1) wet wt.) than wolverine (0.67+/-0.18 microg g(-1) wet wt.). However, mean hepatic Cu concentrations (Ulukhaqtuuq: 5.5+/-0.64; Arviat: 7.1+/-0.49 microg g(-1) wet wt.) in arctic foxes were significantly lower than in wolverines (32+/-3.3 microg g(-1) wet wt.). Hepatic total Hg (THg) concentrations in arctic fox from this study were not significantly different from specimens collected in 1973, suggesting that THg concentrations have not changed dramatically over the past 30 years. The mono-methylmercury (MeHg) concentrations in selected (n=10) arctic fox liver samples from Arviat (0.14+/-0.07 microg g(-1) wet wt.) comprised 14% of THg. While the molar concentrations of THg were correlated with Se in arctic foxes and wolverines, the hepatic Hg/Se molar ratios were consistently lower than unity; suggesting that Se-mediated detoxification pathways of Hg are not overwhelmed at current exposure.

Circum-arctic plate accretion - Isolating part of a pacific plate to form the nucleus of the Arctic Basin

USGS Publications Warehouse

Churkin, M.; Trexler, J.H.

1980-01-01

A mosaic of large lithospheric plates rims the Arctic Ocean Basin, and foldbelts between these plates contain numerous allochthonous microplates. A new model for continental drift and microplate accretion proposes that prior to the late Mesozoic the Kula plate extended from the Pacific into the Arctic. By a process of circumpolar drift and microplate accretion, fragments of the Pacific basin, including parts of the Kula plate, were cut off and isolated in the Arctic Ocean, the Yukon-Koyukuk basin in Alaska, and the Bering Sea. ?? 1980.

Arctic Oil and Natural Gas Potential

EIA Publications

2009-01-01

This paper examines the discovered and undiscovered Arctic oil and natural gas resource base with respect to their location and concentration. The paper also discusses the cost and impediments to developing Arctic oil and natural gas resources, including those issues associated with environmental habitats and political boundaries.

Fine-scale population genetic structure of arctic foxes (Vulpes lagopus) in the High Arctic.

PubMed

Lai, Sandra; Quiles, Adrien; Lambourdière, Josie; Berteaux, Dominique; Lalis, Aude

2017-12-01

The arctic fox (Vulpes lagopus) is a circumpolar species inhabiting all accessible Arctic tundra habitats. The species forms a panmictic population over areas connected by sea ice, but recently, kin clustering and population differentiation were detected even in regions where sea ice was present. The purpose of this study was to examine the genetic structure of a population in the High Arctic using a robust panel of highly polymorphic microsatellites. We analyzed the genotypes of 210 individuals from Bylot Island, Nunavut, Canada, using 15 microsatellite loci. No pattern of isolation-by-distance was detected, but a spatial principal component analysis (sPCA) revealed the presence of genetic subdivisions. Overall, the sPCA revealed two spatially distinct genetic clusters corresponding to the northern and southern parts of the study area, plus another subdivision within each of these two clusters. The north-south genetic differentiation partly matched the distribution of a snow goose colony, which could reflect a preference for settling into familiar ecological environments. Secondary clusters may result from higher-order social structures (neighbourhoods) that use landscape features to delimit their borders. The cryptic genetic subdivisions found in our population may highlight ecological processes deserving further investigations in arctic foxes at larger, regional spatial scales.

Arctic Ocean Pathways in the 21st century

NASA Astrophysics Data System (ADS)

Aksenov, Yevgeny; van Gennip, Simon J.; Kelly, Stephen J.; Popova, Ekaterina E.; Yool, Andrew

2017-04-01

In the last three decades, changes in the Arctic environment have been occurring at an increasing rate. The opening up of large areas of previously sea ice-covered ocean affects the marine environment with potential impacts on Arctic ecosystems, including through changes in Arctic access, industries and societies. Changes to sea ice and surface winds result in large-scale shifts in ocean circulation and oceanic pathways. This study presents a high-resolution analysis of the projected ocean circulation and pathways of the Arctic water masses across the 21st century. The analysis is based on an eddy-permitting high-resolution global simulation of the ocean general circulation model NEMO (Nucleus for European Modelling of the Ocean) at the 1/4-degree horizontal resolution. The atmospheric forcing is from HadGEM2-ES model output from IPCC Assessment Report 5 (AR5) simulations performed for Coupled Model Intercomparison Project 5 (CMIP5), and follow the Representative Concentration Pathway 8.5 (RCP8.5) scenario. During the 21st century the AO experiences a significant warming, with sea surface temperature increased by in excess of 4 deg. C. Annual mean Arctic sea ice thickness drops to less than 0.5m, and the Arctic Ocean is ice-free in summer from the mid-century. We use an off-line tracer technique to investigate Arctic pathways of the Atlantic and Pacific waters (AW and PW respectively) under this future climate. The AW tracers have been released in the eastern Fram Strait and in the western Barents Sea, whereas the PW tracer has been seeded in the Bering Strait. In the second half of the century the upper 1000 m ocean circulation shows a reduction in the eastward AW flow along the continental slopes towards the Makarov and Canada basins and a deviation of the PW flow away from the Beaufort Sea towards the Siberian coast. Strengthening of Arctic boundary current and intensification of the cyclonic gyre in the Nansen basin of the Arctic Ocean is accompanied by

A History of Coastal Research in the Arctic (Invited)

NASA Astrophysics Data System (ADS)

Walker, H. J.; McGraw, M.

2009-12-01

The arctic shoreline is, according to the CIA World Factbook, 45,389 km long. However, a more realistic length from the standpoint of detailed research is the 200,000 km proposed at the 1999 Arctic Coastal Dynamics Workshop. Highly varied in form and material it is dominated by a variety of processes, is relatively remote, is ice-bound much of the year, and has generally been neglected by the scientific community. Before the 20th century, most of the information about its geology, hydrology, geomorphology, and biology was recorded in ship's logs or in explorer's books and was for the most part incidental to the narrative being related. The paucity of specific research is indicated by the relatively few relevant papers included in the more than 100,000 annotated entries published in the 15 volumes of the Arctic Bibliography (1953-1971) and in the nearly as extensive 27 volume bibliography prepared by the Cold Regions Research and Engineering Laboratory (CRREL) between 1952 and 1973. Nonetheless, there were some distinctive research endeavors during the early part of the 20th century; e.g., Leffingwell's 1919 Alaskan Arctic Coast observations, Nansen's 1921 strandflat studies, and Zenkovich's 1937 Murmansk research. During that period some organizations devoted to polar research, especially the USSR's Arctic and Antarctic Research Institute and the Scott Polar Research Institute (both in 1920) were established, although the amount of their research that could be considered coastal and arctic was limited. Specific research of the arctic's shoreline was mainly academic until after World War II when military, economic, industrial, and archaeological interests began demanding reliable, contemporary data. At the time numerous organizations with a primary focus on the Arctic were formed. Included are the Arctic Institute of North America (1945), the Snow, Ice, and Permafrost Research Establishment (latter to become CRREL) and the Office of Naval Research's Arctic Research

An Evaluation of Arctic Ocean Precipitation from Reanalyses for use in Snow Accumulation and Melt Models over Sea Ice

NASA Astrophysics Data System (ADS)

Barrett, A. P.; Stroeve, J.; Liston, G. E.; Tschudi, M. A.; Stewart, S.

2017-12-01

Retrievals of sea ice thickness from satellite- and air-borne sensors require knowledge of snow depth and density. Early retrievals used climatologies of snow depth and density - "The Warren Climatology" - based on observations from 31 Soviet drifting stations between 1957 and 1991. This climatology was the best available Arctic-wide data set at the time. However, it does not account for year-to-year variations in spatial and temporal patterns of snow depth, nor does it account for changes in snow depth over longer time periods. Recent efforts to retrieve ice thickness have used output from global and regional atmospheric reanalyses directly or as input to snow accumulation, density evolution, and melt models to estimate snow depth. While such efforts represent the state-of-the-art in terms of Arctic-wide snow depth fields, there can be large differences between precipitation (and other variables) from reanalyses. Knowledge about these differences and about biases in precipitation magnitude are important for getting the best-possible retrievals of ice thickness. Here, we evaluate fields of total precipitation and snow fall from the NASA MERRA and MERRA2, NOAA CFSR and CFSR version 2, ECMWF ERA-Interim, and Arctic System (ASR) reanalyses with a view to understanding differences in the magnitude, and temporal and spatial patterns of precipitation. Where possible we use observations to understand biases in the reanalysis output. Time series of annual total precipitation for the central Arctic correlate well with all reanalyses showing similar year-to-year variability. Time series for MERRA, MERRA2 and CFSR show no evidence of long-term trends. By contrast ERA-Interim appears to be wetter in the most recent decade. The ASR records only spans 2000 to 2012 but is similar to ERA-Interim. CFSR and MERRA2 are wetter than the other five reanalyses, especially over the eastern Arctic and North Atlantic.

Structural-tectonic zoning of the Arctic

NASA Astrophysics Data System (ADS)

Petrov, Oleg; Sobolev, Nikolay; Morozov, Andrey; Shokalsky, Sergey; Kashubin, Sergey; Grikurov, Garrik; Tolmacheva, Tatiana; Rekant, Pavel; Petrov, Evgeny

2017-04-01

Structural-tectonic zoning of the Arctic is based on the processing of geological and geophysical data and bottom sampling materials produced within the project "Atlas of Geological Maps of the Circumpolar Arctic." Zoning of the Arctic territories has been conducted taking into account the Earth's crust types, age of consolidated basement, and features of geological structure of the sedimentary cover. Developed legend for the zoning scheme incorporates five main groups of elements: continental and oceanic crust, folded platform covers, accretion-collision systems, and provinces of continental cover basalts. An important feature of the structural-tectonic zoning scheme is designation of continental crust in the central regions of the Arctic Ocean, the existence of which is assumed on the basis of numerous geological data. It has been found that most of the Arctic region has continental crust with the exception of the Eurasian Basin and the central part of the Canada Basin, which are characterized by oceanic crust type. Thickness of continental crust from seismic data varies widely: from 30-32 km on the Mendeleev Rise to 18-20 km on the Lomonosov Ridge, decreasing to 8-10 km in rift structures of the Podvodnikov-Makarov Basin at the expense of reduction of the upper granite layer. New data confirm similar basement structure on the western and eastern continental margins of the Eurasian oceanic basin. South to north, areas of Neoproterozoic (Baikalian) and Paleozoic (Ellesmerian) folding are successively distinguished. Neoproterozoic foldbelt is observed in Central Taimyr (Byrranga Mountains). Continuation of this belt in the eastern part of the Arctic is Novosibirsk-Chukchi fold system. Ellesmerian orogen incorporates the northernmost areas of Taimyr and Severnaya Zemlya, wherefrom it can be traced to the Geofizikov Spur of the Lomonosov Ridge and further across the De Long Archipelago and North Chukchi Basin to the north of Alaska Peninsula and in the Beaufort Sea

The Long and Winding Road of Arctic Change Research

NASA Astrophysics Data System (ADS)

Mark, S.

2016-12-01

In the quest to better understand the local, regional and global drivers and impacts of Arctic change, we must not forget that the questions being asked today build on more than a century of research. There were giants before us. Perhaps the first observational evidence that the Arctic was responding to increasing carbon dioxide levels came from a 1986 study by Lachenbruch and Marshall of permafrost temperatures from boreholes in northernmost Alaska. In 1991, Detlef Quadfasel provided the first data on what appeared to be shifts in the ocean circulation, and hints then emerged that the sea ice cover at summer's end was receding. It was then noted that air temperatures over some parts of the Arctic were rising and others were cooling, attended by shifts in weather patterns. While some of this resembled what climate models were projecting, much of it looked like natural climate variability, driven variously by processes internal to the Arctic or linked to lower latitudes via the behavior of the NAO and the Arctic Oscillation. But the changes kept coming. Through a largely self-organizing process, led in considerable part by a small number of leading voices and with the strong support of funding agencies, scientists from diverse disciplines around the world began to find the answers. By the first decade of the 21st century, it was understood that large natural variability in Arctic climate, linked to both within-Arctic and lower-latitude drivers, was superimposed upon warming due to rising greenhouse gas levels, and that what was happening in the Arctic was already influencing lower latitudes. Many issues remain to be resolved. What are the relative roles of different drivers of Arctic amplification? Does Arctic amplification influence weather patterns beyond the Arctic? Will thawing terrestrial or subsea permafrost lead to substantial carbon emissions to the atmosphere, exacerbating global warming? How will sea ice loss affect Arctic ecosystems? How much will the

Arctic Energy Resources: Energy Research

NASA Astrophysics Data System (ADS)

Gryc, George

1984-04-01

Arctic Energy Resources is a volume of 26 papers recording the proceedings of the Comite' Arctique International Conference, held at the Veritas Centre, Oslo, Norway, September 22-24, 1982. This was the fourth of a series of meetings on the Arctic organized by the Comite', an organization established in the Principality of Monaco with the active support of H.S.H. Prince Rainer III. The fourth Conference was opened by H.R.H. Crown Prins Harald of Norway, a noble beginning for a noble objective.The North Polar Region has drawn world attention recently because of several large hydrocarbon and other mineral discoveries and because of major political and environmental actions in the North American Arctic. Since 1923 when Naval Petroleum Reserve number 4 (NPR-4) was established, northern Alaska has been considered a major petroleum province. It was first explored systematically with modern techniques from 1943 to 1953. In 1958, Alaska became a state, and both federal and state lands in northern Alaska were available for private exploration. Building on the knowledge base provided by the Pet-4 program and its spinoff research laboratory at Barrow, industry explored the area east of NPR-4 and discovered the largest hydrocarbon accumulation (9.6 bbl crude oil and 26 Tcf (trillion cubic feet) gas) in North America at Prudhoe Bay. Concerns for environmental impacts, including oil spills, led to the passing of the National Environmental Policy Act in 1969. In 1970, over 9 million acres were set aside, now known as the Arctic National Wildlife Range, and in 1971 the Alaska Native Claims Settlement Act was passed by the U.S. Congress. The Arab oil embargo of 1973 heightened the energy crisis and changed the economic basis for further exploration in the Arctic. The convergence of these events dramatically changed the balance of power and the pace of activity in the North American Arctic.

U.S. Geological Survey circum-arctic resource appraisal

USGS Publications Warehouse

Gautier, D.L.

2011-01-01

Among the greatest uncertainties in future energy supply is the amount of oil and gas yet to be found in the Arctic. Using a probabilistic geology-based methodology, the U.S. Geological Survey has assessed the area north of the Arctic Circle. The Circum-Arctic Resource Appraisal (CARA) consists of three parts: (1) Mapping the sedimentary sequences of the Arctic (Grantz and others 2009), (2) Geologically based estimation of undiscovered technically recoverable petroleum (Gautier and others 2009, discussed in this presentation) and (3) Economic appraisal of the cost of delivering the undiscovered resources to major markets (also reported at this conference by White and others). We estimate that about 30% of the world's undiscovered gas and about 13% of the world's undiscovered oil may be present in the Arctic, mostly offshore under less than 500m of water. Billion BOE-plus accumulations of gas and oil are predicted at a 50% probability in the Kara Sea, Barents Sea, offshore East and West Greenland, Canada, and Alaska. On a BOE basis, undiscovered natural gas is three times more abundant than oil in the Arctic and is concentrated in Russian territory. Oil resources, while critically important to the interests of Arctic countries, are probably not sufficient to significantly shift the current geographic patterns of world oil production. Copyright 2011, Offshore Technology Conference.

Influence of sea ice on Arctic precipitation

PubMed Central

Kopec, Ben G.; Feng, Xiahong; Michel, Fred A.; Posmentier, Eric S.

2016-01-01

Global climate is influenced by the Arctic hydrologic cycle, which is, in part, regulated by sea ice through its control on evaporation and precipitation. However, the quantitative link between precipitation and sea ice extent is poorly constrained. Here we present observational evidence for the response of precipitation to sea ice reduction and assess the sensitivity of the response. Changes in the proportion of moisture sourced from the Arctic with sea ice change in the Canadian Arctic and Greenland Sea regions over the past two decades are inferred from annually averaged deuterium excess (d-excess) measurements from six sites. Other influences on the Arctic hydrologic cycle, such as the strength of meridional transport, are assessed using the North Atlantic Oscillation index. We find that the independent, direct effect of sea ice on the increase of the percentage of Arctic sourced moisture (or Arctic moisture proportion, AMP) is 18.2 ± 4.6% and 10.8 ± 3.6%/100,000 km2 sea ice lost for each region, respectively, corresponding to increases of 10.9 ± 2.8% and 2.7 ± 1.1%/1 °C of warming in the vapor source regions. The moisture source changes likely result in increases of precipitation and changes in energy balance, creating significant uncertainty for climate predictions. PMID:26699509

JAMSTEC Compact Arctic Drifter (J-CAD): A new Generation drifting buoy to observe the Arctic Ocean

NASA Astrophysics Data System (ADS)

Hatakeyama, Kiyoshi; Hosono, Masuo; Shimada, Koji; Kikuchi, Takashi; Nishino, Shigeto

The Arctic Ocean is one of the most sensitive regions to the earth environment changes. Japan Marine Science and Technology Center developed a new drift buoy to observe the Arctic Ocean. The name of the buoy is J-CAD (JAMSTEC Compact Arctic Drifter). From 1991 to 1993, JAMSTEC developed Ice-Ocean Environmental Buoy (IOEB) as a buoy to observe the Arctic Ocean in cooperation with Woods Hole Oceanographic Institution. The J-CAD is the buoy, which adopted the latest technology based on the knowledge and experience of IOEB development. The J-CAD was designed and developed by JAMSTEC and made by a Canadian Company MetOcean. JAMSTEC did design and development, and a Canadian company Met-Ocean made the J-CAD. It acquires meteorological and oceanographic data of the Arctic Ocean, and transmits the data that it measured via satellite. It dose also store the data inside its memory. An Inductive Modem system, which was developed by Sea-Bird Electronics, Inc. in the United States, was adopted in the underwater transmission system that data on each ocean sensor were collected. An ORBCOMM communication system was adopted for the satellite data transmission. J-CAD-1 was installed at 89°41'N 130°20'W on April 24, 2000, and the observation was started. August 1st was the day when 100 days have passed since the J-CAD-1 was installed on the North Pole. And now, the distance J-CAD-1 has covered exceeds 400 km, and it has transmitted data more than 500 k byte. A part of the data is introduced to the public in the homepage (http://w3.jamstec.go.jp: 8338) of the Arctic research group of JAMSTEC.

NASA Sea Ice Validation Program for the Defense Meteorological Satellite Program Special Sensor Microwave Imager

NASA Technical Reports Server (NTRS)

Cavalieri, Donald J. (Editor); Crawford, John P.; Drinkwater, Mark R.; Emery, William J.; Eppler, Duane T.; Farmer, L. Dennis; Fowler, Charles W.; Goodberlet, Mark; Jentz, Robert R.; Milman, Andrew

1992-01-01

The history of the program is described along with the SSM/I sensor, including its calibration and geolocation correction procedures used by NASA, SSM/I data flow, and the NASA program to distribute polar gridded SSM/I radiances and sea ice concentrations (SIC) on CD-ROMs. Following a discussion of the NASA algorithm used to convert SSM/I radiances to SICs, results of 95 SSM/I-MSS Landsat IC comparisons for regions in both the Arctic and the Antarctic are presented. The Landsat comparisons show that the overall algorithm accuracy under winter conditions is 7 pct. on average with 4 pct. negative bias. Next, high resolution active and passive microwave image mosaics from coordinated NASA and Navy aircraft underflights over regions of the Beaufort and Chukchi seas in March 1988 were used to show that the algorithm multiyear IC accuracy is 11 pct. on average with a positive bias of 12 pct. Ice edge crossings of the Bering Sea by the NASA DC-8 aircraft were used to show that the SSM/I 15 pct. ice concentration contour corresponds best to the location of the initial bands at the ice edge. Finally, a summary of results and recommendations for improving the SIC retrievals from spaceborne radiometers are provided.

The central arctic caribou herd

USGS Publications Warehouse

Cameron, Raymond D.; Smith, Walter T.; White, Robert G.; Griffith, Brad; Douglas, David C.; Reynolds, Patricia E.; Rhode, E.B.

2002-01-01

From the mid-1970s through the mid-1980s, use of calving and summer habitats by Central Arctic herd caribou (Rangifer tarandus granti) declined near petroleum development infrastructure on Alaska's arctic coastal plain (Cameron et al. 1979; Cameron and Whitten 1980, Smith and Cameron 1983. Whitten and Cameron 1983a, 1985: Dau and Cameron 1986).With surface development continuing to expand westward from the Prudhoe Bay petroleum development area (Fig. 4.1), concerns arose that the resultant cumulative losses of habitat would eventually reduce productivity of the caribou herd. Specifically, reduced access of adult females to preferred foraging areas might adversely affect growth and fattening (Elison et al. 1986. Clough et al. 1987), in turn depressing calf production (Dauphiné 1976, Thomas 1982, Reimers 1983, White 1983, Eloranta and Nieminen 1986. Lenvik et al. 1988, Thomas and Kiliaan 1991) and survival (Haukioja and Salovaara 1978, Rognmo et al. 1983, Skogland 1984, Eloranta and Nieminen 1986, Adamczewski et al. 1987).Those concerns, though justified in theory, lacked empirical support. With industrial development in arctic Alaska virtually unprecedented, there was little basis for predicting the extent and duration of habitat loss, much less the secondary short- and long-term effects on the well-being of a particular caribou herd.Furthermore, despite a general acceptance that body condition and fecundity of the females are functionally related for reindeer and caribou, it seemed unlikely that any single model would apply to all subspecies of Rangifer, and perhaps not even within a subspecies in different geographic regions. We therefore lacked a complete understanding of the behavioral responses of arctic caribou to industrial development, the manner in which access to habitats might be affected, and how changes in habitat use might translate into measurable effects on fecundity and herd growth rate.Our study addressed the following objectives: 1) estimate

Improving coordination and integration of observations of Arctic change

NASA Astrophysics Data System (ADS)

Perovich, Donald; Payne, John; Eicken, Hajo

2012-10-01

U.S. Arctic Observing Coordination Workshop;Anchorage, Alaska, 20-22 March 2012 The Arctic is undergoing tremendous changes. Permafrost is thawing, ice sheets are melting, and sea ice is thinning and retreating. These changes are impacting ecosystems and human activities. Observing, understanding, and responding to these changes are the central themes of the U.S. Interagency Study of Environmental Arctic Change (SEARCH, http://www.arcus.org/search/index.php). SEARCH brings together academic and government agency scientists and stakeholders to prioritize, plan, conduct, and synthesize research focused on Arctic environmental change. The U.S. Arctic Observing Coordination Workshop (http://www.arcus.org/search/meetings/2012/coordination-workshop/) focused on two key themes for cross-disciplinary and cross-agency collaboration: (1) understanding and predicting sea ice changes and their consequences for ecosystems, human activities, and climate and (2) determining consequences of loss and warming of shallow permafrost on Arctic and global systems.

Research Applications of Data from Arctic Ocean Drifting Platforms: The Arctic Buoy Program and the Environmental Working Group CD's.

NASA Astrophysics Data System (ADS)

Moritz, R. E.; Rigor, I.

2006-12-01

ABSTRACT: The Arctic Buoy Program was initiated in 1978 to measure surface air pressure, surface temperature and sea-ice motion in the Arctic Ocean, on the space and time scales of synoptic weather systems, and to make the data available for research, forecasting and operations. The program, subsequently renamed the International Arctic Buoy Programme (IABP), has endured and expanded over the past 28 years. A hallmark of the IABP is the production, dissemination and archival of research-quality datasets and analyses. These datasets have been used by the authors of over 500 papers on meteorolgy, sea-ice physics, oceanography, air-sea interactions, climate, remote sensing and other topics. Elements of the IABP are described briefly, including measurements, analysis, data dissemination and data archival. Selected highlights of the research applications are reviewed, including ice dynamics, ocean-ice modeling, low-frequency variability of Arctic air-sea-ice circulation, and recent changes in the age, thickness and extent of Arctic Sea-ice. The extended temporal coverage of the data disseminated on the Environmental Working Group CD's is important for interpreting results in the context of climate.

Fourth international circumpolar arctic vegetation mapping workshop

USGS Publications Warehouse

Raynolds, Martha K.; Markon, C.J.

2002-01-01

During the week of April 10, 2001, the Fourth International Circumpolar Arctic Vegetation Mapping Workshop was held in Moscow, Russia. The purpose of this meeting was to bring together the vegetation scientists working on the Circumpolar Arctic Vegetation Map (CAVM) to (1) review the progress of current mapping activities, (2) discuss and agree upon a standard set of arctic tundra subzones, (3) plan for the production and dissemination of a draft map, and (4) begin work on a legend for the final map.

Status and Impacts of Arctic Freshwater Export

NASA Astrophysics Data System (ADS)

Haine, T. W. N.

2017-12-01

Large freshwater anomalies clearly exist in the Arctic Ocean. For example, liquid freshwater has accumulated in the Beaufort Gyre in the decade of the 2000s compared to 1980-2000, with an extra ≈5000 km3—about 25%—being stored. The sources of freshwater to the Arctic from precipitation and runoff have increased between these periods (most of the evidence comes from models). Despite flux increases from 2001 to 2011, it is uncertain if the marine freshwater source through Bering Strait for the 2000s has changed, as observations in the 1980s and 1990s are incomplete. The marine freshwater fluxes draining the Arctic through Fram and Davis straits are also insignificantly different. In this way, the balance of sources and sinks of freshwater to the Arctic, Canadian Arctic Archipelago (CAA), and Baffin Bay shifted to about 1200±730 km3yr-1 freshening the region, on average, during the 2000s. The observed accumulation of liquid freshwater is consistent with this increased supply and the loss of freshwater from sea ice (Figure, right). Evidence exists that such discharges can impact the Atlantic meridional overturning circulation, and hence Atlantic sector climate. Nevertheless, it appears that the observed AMOC variability since 2004, when high quality measurements began, is not attributable to anthropogenic influence. This work is based on, and updated from, Haine et al. (2015), Carmack et al. (2016), and Haine (2016). Haine, T. W. N. Ocean science: Vagaries of Atlantic overturning. Nature Geoscience, 9, 479-480, 10.1038/ngeo2748, 2016. T. W. N. Haine et al., Arctic Freshwater Export: Status, Mechanisms, and Prospects, Global Planetary Change, 125, 13-35, 10.1016/j.glopacha.2014.11.013, 2015. E. Carmack et al., Fresh water and its role in the Arctic Marine System: sources, disposition, storage, export, and physical and biogeochemical consequences in the Arctic and global oceans. J. G. Res. Biogeosciences, 10.1002/2015JG003140, 2016.

Arctic vs. Tropical Influence and Over the Period of Arctic Amplification including Winter 2015/16

NASA Astrophysics Data System (ADS)

Cohen, J. L.; Francis, J. A.; Pfeiffer, K.

2016-12-01

The tropics in general and El Niño/Southern Oscillation (ENSO) in particular are almost exclusively relied upon for seasonal forecasting. Much less considered and certainly more controversial is the idea that Arctic variability is influencing mid-latitude weather. However, since the late 1980s and early 1990s the Arctic has undergone the most rapid warming observed globally, referred to as Arctic amplification (AA), which has coincided with an observed increase in extreme weather. Analysis of observed trends in hemispheric circulation over the period of AA more closely resembles variability associated with Arctic boundary forcings than with tropical forcing. Furthermore, analysis of intra-seasonal temperature variability shows that the cooling in mid-latitude winter temperatures has been accompanied by an increase in temperature variability and not a decrease, popularly referred to as "weather whiplash." When a record El Niño occurred this past winter, it should have been an opportunity to showcase decades of research and resources dedicated to the study of the ENSO phenomenon and its global impacts. However the dynamical forecasts performed poorly this past winter. Instead we will show that many of the significant circulation anomalies of this past winter are related to high latitude processes. We believe that the failed forecasts of this past winter will serve as a watershed moment and an inflection point in climate science. Climate science requires a paradigm shift in order to improve long-range forecasts. Less reliance on the tropics and exploration of new regions of predictability, including the Arctic, are required.

4D Arctic: A Glimpse into the Structure and Evolution of the Arctic in the Light of New Geophysical Maps, Plate Tectonics and Tomographic Models.

PubMed

Gaina, Carmen; Medvedev, Sergei; Torsvik, Trond H; Koulakov, Ivan; Werner, Stephanie C

Knowledge about the Arctic tectonic structure has changed in the last decade as a large number of new datasets have been collected and systematized. Here, we review the most updated, publicly available Circum-Arctic digital compilations of magnetic and gravity data together with new models of the Arctic's crust. Available tomographic models have also been scrutinized and evaluated for their potential to reveal the deeper structure of the Arctic region. Although the age and opening mechanisms of the Amerasia Basin are still difficult to establish in detail, interpreted subducted slabs that reside in the High Arctic's lower mantle point to one or two episodes of subduction that consumed crust of possibly Late Cretaceous-Jurassic age. The origin of major igneous activity during the Cretaceous in the central Arctic (the Alpha-Mendeleev Ridge) and in the proximity of rifted margins (the so-called High Arctic Large Igneous Province-HALIP) is still debated. Models of global plate circuits and the connection with the deep mantle are used here to re-evaluate a possible link between Arctic volcanism and mantle plumes.

The Arctic Cooperative Data and Information System: Data Management Support for the NSF Arctic Research Program (Invited)

NASA Astrophysics Data System (ADS)

Moore, J.; Serreze, M. C.; Middleton, D.; Ramamurthy, M. K.; Yarmey, L.

2013-12-01

The NSF funds the Advanced Cooperative Arctic Data and Information System (ACADIS), url: (http://www.aoncadis.org/). It serves the growing and increasingly diverse data management needs of NSF's arctic research community. The ACADIS investigator team combines experienced data managers, curators and software engineers from the NSIDC, UCAR and NCAR. ACADIS fosters scientific synthesis and discovery by providing a secure long-term data archive to NSF investigators. The system provides discovery and access to arctic related data from this and other archives. This paper updates the technical components of ACADIS, the implementation of best practices, the value of ACADIS to the community and the major challenges facing this archive for the future in handling the diverse data coming from NSF Arctic investigators. ACADIS provides sustainable data management, data stewardship services and leadership for the NSF Arctic research community through open data sharing, adherence to best practices and standards, capitalizing on appropriate evolving technologies, community support and engagement. ACADIS leverages other pertinent projects, capitalizing on appropriate emerging technologies and participating in emerging cyberinfrastructure initiatives. The key elements of ACADIS user services to the NSF Arctic community include: data and metadata upload; support for datasets with special requirements; metadata and documentation generation; interoperability and initiatives with other archives; and science support to investigators and the community. Providing a self-service data publishing platform requiring minimal curation oversight while maintaining rich metadata for discovery, access and preservation is challenging. Implementing metadata standards are a first step towards consistent content. The ACADIS Gateway and ADE offer users choices for data discovery and access with the clear objective of increasing discovery and use of all Arctic data especially for analysis activities

Photosynthesis, Earth System Models and the Arctic

NASA Astrophysics Data System (ADS)

Rogers, A.; Sloan, V. L.; Xu, C.; Wullschleger, S. D.

2013-12-01

The primary goal of Earth System Models (ESMs) is to improve understanding and projection of future global change. In order to do this they must accurately represent the huge carbon fluxes associated with the terrestrial carbon cycle. Photosynthetic CO2 uptake is the largest of these fluxes, and is well described by the Farquhar, von Caemmerer and Berry (FvCB) model of photosynthesis. Most ESMs use a derivation of the FvCB model to calculate gross primary productivity (GPP). One of the key parameters required by the FvCB model is an estimate of the maximum rate of carboxylation by the enzyme Rubisco (Vc,max). In ESMs the parameter Vc,max is usually fixed for a given plant functional type (PFT). Although Arctic GPP a small flux relative to global GPP, uncertainty is large. Only four ESMs currently have an explicit Arctic PFT and the data used to derive Vc,max for the Arctic PFT in these models relies on small data sets and unjustified assumptions. As part of a multidisciplinary project to improve the representation of the Arctic in ESMs (Next Generation Ecosystem Experiments - Arctic) we examined the derivation of Vc,max in current Arctic PFTs and estimated Vc,max for 12 species representing both dominant vegetation and key PFTs growing on the Barrow Environmental Observatory, Barrow, AK. The values of Vc,max currently used to represent Arctic PFTs in ESMs are 70% lower than the values we measured in these species. Separate measurements of CO2 assimilation (A) made at ambient conditions were compared with A modeled using the Vc,max values we measured in Barrow and those used by the ESMs. The A modeled with the Vc,max values used by the ESMs was 80% lower than the observed A. When our measured Vc,max values were used, modeled A was within 5% of observed A. Examination of the derivation of Vc,max in ESMs identified that the cause of the relatively low Vc,max value was the result of underestimating both the leaf N content and the investment of that N in Rubisco. Here

Cruise to the Chukchi Borderland, Arctic Ocean

USGS Publications Warehouse

Grantz, Arthur; ,

1993-01-01

Oceanography and geology were the principal focuses of the U.S. Geological Survey-sponsored expedition Arctic Summer West '92, which traveled to the eastern part of the Chukchi Borderland of the Amerasia Basin, western Arctic Ocean. The expedition took place from August 20 to September 25, 1992, aboard the Coast Guard cutter Polar Star. USGS investigated the geologic framework and tectonic origin of the borderland, Arctic Quaternary paleoclimate, sea-ice transport of particulate matter in the Beaufort Gyre, and possible radionuclide contamination of the water column and seafloor off Alaska from sources in the Russian Arctic. Researchers from five other institutions studied the area's oceanography, age of the water column, paleoenvironment of the Holocene sediment, physical properties and synthetic-aperture radar backscatter of sea ice, and the drop-stone content of late Quaternary sediment.

Deep Arctic Ocean warming during the last glacial cycle

USGS Publications Warehouse

Cronin, T. M.; Dwyer, G.S.; Farmer, J.; Bauch, H.A.; Spielhagen, R.F.; Jakobsson, M.; Nilsson, J.; Briggs, W.M.; Stepanova, A.

2012-01-01

In the Arctic Ocean, the cold and relatively fresh water beneath the sea ice is separated from the underlying warmer and saltier Atlantic Layer by a halocline. Ongoing sea ice loss and warming in the Arctic Ocean have demonstrated the instability of the halocline, with implications for further sea ice loss. The stability of the halocline through past climate variations is unclear. Here we estimate intermediate water temperatures over the past 50,000 years from the Mg/Ca and Sr/Ca values of ostracods from 31 Arctic sediment cores. From about 50 to 11 kyr ago, the central Arctic Basin from 1,000 to 2,500 m was occupied by a water mass we call Glacial Arctic Intermediate Water. This water mass was 1–2 °C warmer than modern Arctic Intermediate Water, with temperatures peaking during or just before millennial-scale Heinrich cold events and the Younger Dryas cold interval. We use numerical modelling to show that the intermediate depth warming could result from the expected decrease in the flux of fresh water to the Arctic Ocean during glacial conditions, which would cause the halocline to deepen and push the warm Atlantic Layer into intermediate depths. Although not modelled, the reduced formation of cold, deep waters due to the exposure of the Arctic continental shelf could also contribute to the intermediate depth warming.

The adaptation challenge in the Arctic

NASA Astrophysics Data System (ADS)

Ford, James D.; McDowell, Graham; Pearce, Tristan

2015-12-01

It is commonly asserted that human communities in the Arctic are highly vulnerable to climate change, with the magnitude of projected impacts limiting their ability to adapt. At the same time, an increasing number of field studies demonstrate significant adaptive capacity. Given this paradox, we review climate change adaptation, resilience and vulnerability research to identify and characterize the nature and magnitude of the adaptation challenge facing the Arctic. We find that the challenge of adaptation in the Arctic is formidable, but suggest that drivers of vulnerability and barriers to adaptation can be overcome, avoided or reduced by individual and collective efforts across scales for many, if not all, climate change risks.

The 2008 Circum-Arctic Resource Appraisal

USGS Publications Warehouse

Moore, Thomas E.; Gautier, Donald L.

2017-11-15

Professional Paper 1824 comprises 30 chapters by various U.S. Geological Survey authors, including introduction and methodology chapters, which together provide documentation of the geological basis and methodology of the 2008 Circum-Arctic Resource Appraisal, results of which were first released in August 2008.  Twenty-eight chapters summarize the petroleum geology and resource potential of individual, geologically defined provinces north of the Arctic Circle, including those of northern Alaska, northern Canada, east and west Greenland, and most of Arctic Russia, as well as certain offshore areas of the north Atlantic Basin and the Polar Sea. Appendixes tabulate the input and output information used during the assessment.

Arctic Warming Signals from Satellite Observations

NASA Technical Reports Server (NTRS)

Comiso, Josefino C.

2005-01-01

Global warming signals are expected to be amplified in the Arctic primarily because of ice-albedo feedback associated with the high reflectivity of ice and snow that blankets much of the region. The Arctic had been a poorly explored territory basically because of its general inaccessibility on account of extremely harsh weather conditions and the dominant presence of thick perennial ice in the region. The advent of satellite remote sensing systems since the 1960s, however, enabled the acquisition of synoptic data that depict in good spatial detail the temporal changes of many Arctic surface parameters. Among the surface parameters that have been studied using space based systems are surface temperature, sea ice concentration, snow cover, surface albedo and phytoplankton concentration. Associated atmospheric parameters, such as cloud cover, temperature profile, ozone concentration, and aerosol have also been derived. Recent observational and phenomenological studies have indeed revealed progressively changing conditions in the Arctic during the last few decades (e g , Walsh et al. 1996; Serreze et al 2000; Comiso and Parkinson 2004). The changes included declines in the extent and area of surfaces covered by sea ice and snow, increases in melt area over the Greenland ice sheets, thawing of the permafrost, warming in the troposphere, and retreat of the glaciers. These observations are consistent with the observed global warming that has been associated with the increasing concentration of greenhouse gases in the atmosphere (Karl and Trenberth 2003) and confirmed by modeling studies (Holland and Bitz, 2003). The Arctic system, however, is still not well understood complicated by a largely fluctuating wind circulation and atmospheric conditions (Proshutinsky and Johnson 1997) and controlled by what is now known as the Arctic Oscillation (AO) which provides a measure of the strength of atmospheric activities in the region (Thompson and Wallace 1998). Meanwhile, the

Trajectory of the arctic as an integrated system

USGS Publications Warehouse

Hinzman, Larry; Deal, Clara; McGuire, Anthony David; Mernild, Sebastian H.; Polyakov, Igor V.; Walsh, John E.

2013-01-01

Although much remains to be learned about the Arctic and its component processes, many of the most urgent scientific, engineering, and social questions can only be approached through a broader system perspective. Here, we address interactions between components of the Arctic System and assess feedbacks and the extent to which feedbacks (1) are now underway in the Arctic; and (2) will shape the future trajectory of the Arctic system. We examine interdependent connections among atmospheric processes, oceanic processes, sea-ice dynamics, marine and terrestrial ecosystems, land surface stocks of carbon and water, glaciers and ice caps, and the Greenland ice sheet. Our emphasis on the interactions between components, both historical and anticipated, is targeted on the feedbacks, pathways, and processes that link these different components of the Arctic system. We present evidence that the physical components of the Arctic climate system are currently in extreme states, and that there is no indication that the system will deviate from this anomalous trajectory in the foreseeable future. The feedback for which the evidence of ongoing changes is most compelling is the surface albedo-temperature feedback, which is amplifying temperature changes over land (primarily in spring) and ocean (primarily in autumn-winter). Other feedbacks likely to emerge are those in which key processes include surface fluxes of trace gases, changes in the distribution of vegetation, changes in surface soil moisture, changes in atmospheric water vapor arising from higher temperatures and greater areas of open ocean, impacts of Arctic freshwater fluxes on the meridional overturning circulation of the ocean, and changes in Arctic clouds resulting from changes in water vapor content.

Trajectory of the Arctic as an integrated system.

PubMed

Hinzman, Larry D; Deal, Clara J; McGuire, A David; Mernild, Sebastian H; Polyakov, Igor V; Walsh, John E

2013-12-01

Although much remains to be learned about the Arctic and its component processes, many of the most urgent scientific, engineering, and social questions can only be approached through a broader system perspective. Here, we address interactions between components of the Arctic system and assess feedbacks and the extent to which feedbacks (1) are now underway in the Arctic and (2) will shape the future trajectory of the Arctic system. We examine interdependent connections among atmospheric processes, oceanic processes, sea-ice dynamics, marine and terrestrial ecosystems, land surface stocks of carbon and water, glaciers and ice caps, and the Greenland ice sheet. Our emphasis on the interactions between components, both historical and anticipated, is targeted on the feedbacks, pathways, and processes that link these different components of the Arctic system. We present evidence that the physical components of the Arctic climate system are currently in extreme states, and that there is no indication that the system will deviate from this anomalous trajectory in the foreseeable future. The feedback for which the evidence of ongoing changes is most compelling is the surface albedo-temperature feedback, which is amplifying temperature changes over land (primarily in spring) and ocean (primarily in autumn-winter). Other feedbacks likely to emerge are those in which key processes include surface fluxes of trace gases, changes in the distribution of vegetation, changes in surface soil moisture, changes in atmospheric water vapor arising from higher temperatures and greater areas of open ocean, impacts of Arctic freshwater fluxes on the meridional overturning circulation of the ocean, and changes in Arctic clouds resulting from changes in water vapor content.

The Arctic Observing Viewer: A Web-mapping Application for U.S. Arctic Observing Activities

NASA Astrophysics Data System (ADS)

Cody, R. P.; Manley, W. F.; Gaylord, A. G.; Kassin, A.; Villarreal, S.; Barba, M.; Dover, M.; Escarzaga, S. M.; Habermann, T.; Kozimor, J.; Score, R.; Tweedie, C. E.

2015-12-01

Although a great deal of progress has been made with various arctic observing efforts, it can be difficult to assess such progress when so many agencies, organizations, research groups and others are making such rapid progress over such a large expanse of the Arctic. To help meet the strategic needs of the U.S. SEARCH-AON program and facilitate the development of SAON and other related initiatives, the Arctic Observing Viewer (AOV; http://ArcticObservingViewer.org) has been developed. This web mapping application compiles detailed information pertaining to U.S. Arctic Observing efforts. Contributing partners include the U.S. NSF, USGS, ACADIS, ADIwg, AOOS, a2dc, AON, ARMAP, BAID, IASOA, INTERACT, and others. Over 7700 observation sites are currently in the AOV database and the application allows users to visualize, navigate, select, advance search, draw, print, and more. During 2015, the web mapping application has been enhanced by the addition of a query builder that allows users to create rich and complex queries. AOV is founded on principles of software and data interoperability and includes an emerging "Project" metadata standard, which uses ISO 19115-1 and compatible web services. Substantial efforts have focused on maintaining and centralizing all database information. In order to keep up with emerging technologies, the AOV data set has been structured and centralized within a relational database and the application front-end has been ported to HTML5 to enable mobile access. Other application enhancements include an embedded Apache Solr search platform which provides users with the capability to perform advance searches and an administration web based data management system that allows administrators to add, update, and delete information in real time. We encourage all collaborators to use AOV tools and services for their own purposes and to help us extend the impact of our efforts and ensure AOV complements other cyber-resources. Reinforcing dispersed but

Implementation of U.S. Policy in the Arctic

DTIC Science & Technology

2013-05-23

additional icebreakers in order to conduct more research, project power and assert sovereignty, gain Arctic domain awareness, ensure safety of Arctic...most of the year create obstructions or exceptional hazards to navigation, and pollution of the marine environment could cause major harm to or...oversight of safety and security of 36 Arctic Council, The Ilulissat Declaration (Ilulissat, Greenland, 2008), 1. 37 US cases will be discussed

Communicating Climate and Ecosystem Change in the Arctic

NASA Astrophysics Data System (ADS)

Soreide, N. N.; Overland, J. E.; Calder, J. A.; Rodionov, S.

2005-12-01

There is an explosion of interest in Northern Hemisphere climate, highlighting the importance of recent changes in the Arctic on mid-latitude climate and its impact on marine and terrestrial ecosystems. Traditional sea ice and tundra dominated arctic ecosystems are being reorganizing into warmer sub-arctic ecosystem types. Over the previous two years we have developed a comprehensive, near real-time arctic change detection protocol to track physical and biological changes for presentation on the web: http://www.arctic.noaa.gov/detect. The effort provides a continuous update to the Arctic Climate Impact Assessment (ACIA) Report, released in November 2004. Principles for the protocol include an accessible narrative style, scientifically credible and objective indicators, notes multiple uses for the information, acknowledges uncertainties, and balances having too many indicators-which leads to information overload-and too few-which does not capture the complexity of the system. Screening criteria include concreteness, public awareness, being understandable, availability of historical time series, and sensitivity. The site provides sufficient information for an individual to make their own assessment regarding the balance of the evidence for tracking change. The product provides an overview, recent news, links to many arctic websites, and highlights climate, global impacts, land and marine ecosystems, and human consequences. Since its inception a year ago, it has averaged about 9000 hits an day on the web, and is a major information source as determined by Google search. The future direction focuses on understanding the causes for change. In spring 2005 we also presented a near real-time ecological and climatic surveillance website for the Bering Sea: www.beringclimate.noaa.gov. The site provides up-to-date information which ties northward shifts of fish, invertebrate and marine mammal populations to physical changes in the Arctic. This site is more technical than the

Arctic pathways of Pacific Water: Arctic Ocean Model Intercomparison experiments

PubMed Central

Karcher, Michael; Proshutinsky, Andrey; Gerdes, Rüdiger; de Cuevas, Beverly; Golubeva, Elena; Kauker, Frank; Nguyen, An T.; Platov, Gennady A.; Wadley, Martin; Watanabe, Eiji; Coward, Andrew C.; Nurser, A. J. George

2016-01-01

Abstract Pacific Water (PW) enters the Arctic Ocean through Bering Strait and brings in heat, fresh water, and nutrients from the northern Bering Sea. The circulation of PW in the central Arctic Ocean is only partially understood due to the lack of observations. In this paper, pathways of PW are investigated using simulations with six state‐of‐the art regional and global Ocean General Circulation Models (OGCMs). In the simulations, PW is tracked by a passive tracer, released in Bering Strait. Simulated PW spreads from the Bering Strait region in three major branches. One of them starts in the Barrow Canyon, bringing PW along the continental slope of Alaska into the Canadian Straits and then into Baffin Bay. The second begins in the vicinity of the Herald Canyon and transports PW along the continental slope of the East Siberian Sea into the Transpolar Drift, and then through Fram Strait and the Greenland Sea. The third branch begins near the Herald Shoal and the central Chukchi shelf and brings PW into the Beaufort Gyre. In the models, the wind, acting via Ekman pumping, drives the seasonal and interannual variability of PW in the Canadian Basin of the Arctic Ocean. The wind affects the simulated PW pathways by changing the vertical shear of the relative vorticity of the ocean flow in the Canada Basin. PMID:27818853

Arctic pathways of Pacific Water: Arctic Ocean Model Intercomparison experiments.

PubMed

Aksenov, Yevgeny; Karcher, Michael; Proshutinsky, Andrey; Gerdes, Rüdiger; de Cuevas, Beverly; Golubeva, Elena; Kauker, Frank; Nguyen, An T; Platov, Gennady A; Wadley, Martin; Watanabe, Eiji; Coward, Andrew C; Nurser, A J George

2016-01-01

Pacific Water (PW) enters the Arctic Ocean through Bering Strait and brings in heat, fresh water, and nutrients from the northern Bering Sea. The circulation of PW in the central Arctic Ocean is only partially understood due to the lack of observations. In this paper, pathways of PW are investigated using simulations with six state-of-the art regional and global Ocean General Circulation Models (OGCMs). In the simulations, PW is tracked by a passive tracer, released in Bering Strait. Simulated PW spreads from the Bering Strait region in three major branches. One of them starts in the Barrow Canyon, bringing PW along the continental slope of Alaska into the Canadian Straits and then into Baffin Bay. The second begins in the vicinity of the Herald Canyon and transports PW along the continental slope of the East Siberian Sea into the Transpolar Drift, and then through Fram Strait and the Greenland Sea. The third branch begins near the Herald Shoal and the central Chukchi shelf and brings PW into the Beaufort Gyre. In the models, the wind, acting via Ekman pumping, drives the seasonal and interannual variability of PW in the Canadian Basin of the Arctic Ocean. The wind affects the simulated PW pathways by changing the vertical shear of the relative vorticity of the ocean flow in the Canada Basin.

Changing Arctic Ocean freshwater pathways.

PubMed

Morison, James; Kwok, Ron; Peralta-Ferriz, Cecilia; Alkire, Matt; Rigor, Ignatius; Andersen, Roger; Steele, Mike

2012-01-04

Freshening in the Canada basin of the Arctic Ocean began in the 1990s and continued to at least the end of 2008. By then, the Arctic Ocean might have gained four times as much fresh water as comprised the Great Salinity Anomaly of the 1970s, raising the spectre of slowing global ocean circulation. Freshening has been attributed to increased sea ice melting and contributions from runoff, but a leading explanation has been a strengthening of the Beaufort High--a characteristic peak in sea level atmospheric pressure--which tends to accelerate an anticyclonic (clockwise) wind pattern causing convergence of fresh surface water. Limited observations have made this explanation difficult to verify, and observations of increasing freshwater content under a weakened Beaufort High suggest that other factors must be affecting freshwater content. Here we use observations to show that during a time of record reductions in ice extent from 2005 to 2008, the dominant freshwater content changes were an increase in the Canada basin balanced by a decrease in the Eurasian basin. Observations are drawn from satellite data (sea surface height and ocean-bottom pressure) and in situ data. The freshwater changes were due to a cyclonic (anticlockwise) shift in the ocean pathway of Eurasian runoff forced by strengthening of the west-to-east Northern Hemisphere atmospheric circulation characterized by an increased Arctic Oscillation index. Our results confirm that runoff is an important influence on the Arctic Ocean and establish that the spatial and temporal manifestations of the runoff pathways are modulated by the Arctic Oscillation, rather than the strength of the wind-driven Beaufort Gyre circulation.

Lidar measurements of polar stratospheric clouds during the 1989 airborne Arctic stratospheric expedition

NASA Technical Reports Server (NTRS)

Ismail, Syed; Browell, Edward V.

1991-01-01

The Airborne Arctic Stratospheric Expedition (AASE) was conducted during January to February 1989 from the Sola Air Station, Norway. As part of this expedition, the NASA Langley Research Center's multiwavelength airborne lidar system was flown on the NASA Ames Research Center's DC-8 aircraft to measure ozone (O3) and aerosol profiles in the region of the polar vortex. The lidar system simultaneously transmitted laser beams at 1064, 603, 311, and 301.5 nm to measure atmospheric scattering, polarization and O3 profiles. Long range flights were made between Stavanger, Norway, and the North Pole, and between 40 deg W and 20 deg E meridians. Eleven flights were made, each flight lasting an average of 10 hours covering about 8000 km. Atmospheric scattering ratios, aerosol polarizations, and aerosol scattering ratio wavelength dependences were derived from the lidar measurements to altitudes above 27 km. The details of the aerosol scattering properties of lidar observations in the IR, VIS, and UV regions are presented along with correlations with the national meteorological Center's temperature profiles.

Future Arctic climate changes: Adaptation and mitigation time scales

NASA Astrophysics Data System (ADS)

Overland, James E.; Wang, Muyin; Walsh, John E.; Stroeve, Julienne C.

2014-02-01

The climate in the Arctic is changing faster than in midlatitudes. This is shown by increased temperatures, loss of summer sea ice, earlier snow melt, impacts on ecosystems, and increased economic access. Arctic sea ice volume has decreased by 75% since the 1980s. Long-lasting global anthropogenic forcing from carbon dioxide has increased over the previous decades and is anticipated to increase over the next decades. Temperature increases in response to greenhouse gases are amplified in the Arctic through feedback processes associated with shifts in albedo, ocean and land heat storage, and near-surface longwave radiation fluxes. Thus, for the next few decades out to 2040, continuing environmental changes in the Arctic are very likely, and the appropriate response is to plan for adaptation to these changes. For example, it is very likely that the Arctic Ocean will become seasonally nearly sea ice free before 2050 and possibly within a decade or two, which in turn will further increase Arctic temperatures, economic access, and ecological shifts. Mitigation becomes an important option to reduce potential Arctic impacts in the second half of the 21st century. Using the most recent set of climate model projections (CMIP5), multimodel mean temperature projections show an Arctic-wide end of century increase of +13°C in late fall and +5°C in late spring for a business-as-usual emission scenario (RCP8.5) in contrast to +7°C in late fall and +3°C in late spring if civilization follows a mitigation scenario (RCP4.5). Such temperature increases demonstrate the heightened sensitivity of the Arctic to greenhouse gas forcing.

Climate of the Arctic marine environment.

PubMed

Walsh, John E

2008-03-01

The climate of the Arctic marine environment is characterized by strong seasonality in the incoming solar radiation and by tremendous spatial variations arising from a variety of surface types, including open ocean, sea ice, large islands, and proximity to major landmasses. Interannual and decadal-scale variations are prominent features of Arctic climate, complicating the distinction between natural and anthropogenically driven variations. Nevertheless, climate models consistently indicate that the Arctic is the most climatically sensitive region of the Northern Hemisphere, especially near the sea ice margins. The Arctic marine environment has shown changes over the past several decades, and these changes are part of a broader global warming that exceeds the range of natural variability over the past 1000 years. Record minima of sea ice coverage during the past few summers and increased melt from Greenland have important implications for the hydrographic regime of the Arctic marine environment. The recent changes in the atmosphere (temperature, precipitation, pressure), sea ice, and ocean appear to be a coordinated response to systematic variations of the large-scale atmospheric circulation, superimposed on a general warming that is likely associated with increasing greenhouse gases. The changes have been sufficiently large in some sectors (e.g., the Bering/Chukchi Seas) that consequences for marine ecosystems appear to be underway. Global climate models indicate an additional warming of several degrees Celsius in much of the Arctic marine environment by 2050. However, the warming is seasonal (largest in autumn and winter), spatially variable, and closely associated with further retreat of sea ice. Additional changes predicted for 2050 are a general decrease of sea level pressure (largest in the Bering sector) and an increase of precipitation. While predictions of changes in storminess cannot be made with confidence, the predicted reduction of sea ice cover will

Cloud-Scale Numerical Modeling of the Arctic Boundary Layer

NASA Technical Reports Server (NTRS)

Krueger, Steven K.

1998-01-01

The interactions between sea ice, open ocean, atmospheric radiation, and clouds over the Arctic Ocean exert a strong influence on global climate. Uncertainties in the formulation of interactive air-sea-ice processes in global climate models (GCMs) result in large differences between the Arctic, and global, climates simulated by different models. Arctic stratus clouds are not well-simulated by GCMs, yet exert a strong influence on the surface energy budget of the Arctic. Leads (channels of open water in sea ice) have significant impacts on the large-scale budgets during the Arctic winter, when they contribute about 50 percent of the surface fluxes over the Arctic Ocean, but cover only 1 to 2 percent of its area. Convective plumes generated by wide leads may penetrate the surface inversion and produce condensate that spreads up to 250 km downwind of the lead, and may significantly affect the longwave radiative fluxes at the surface and thereby the sea ice thickness. The effects of leads and boundary layer clouds must be accurately represented in climate models to allow possible feedbacks between them and the sea ice thickness. The FIRE III Arctic boundary layer clouds field program, in conjunction with the SHEBA ice camp and the ARM North Slope of Alaska and Adjacent Arctic Ocean site, will offer an unprecedented opportunity to greatly improve our ability to parameterize the important effects of leads and boundary layer clouds in GCMs.

Sea Ice Outlook for September 2015 June Report - NASA Global Modeling and Assimilation Office

NASA Technical Reports Server (NTRS)

Cullather, Richard I.; Keppenne, Christian L.; Marshak, Jelena; Pawson, Steven; Schubert, Siegfried D.; Suarez, Max J.; Vernieres, Guillaume; Zhao, Bin

2015-01-01

The recent decline in perennial sea ice cover in Arctic Ocean is a topic of enormous scientific interest and has relevance to a broad variety of scientific disciplines and human endeavors including biological and physical oceanography, atmospheric circulation, high latitude ecology, the sustainability of indigenous communities, commerce, and resource exploration. A credible seasonal prediction of sea ice extent would be of substantial use to many of the stakeholders in these fields and may also reveal details on the physical processes that result in the current trends in the ice cover. Forecasts are challenging due in part to limitations in the polar observing network, the large variability in the climate system, and an incomplete knowledge of the significant processes. Nevertheless it is a useful to understand the current capabilities of high latitude seasonal forecasting and identify areas where such forecasts may be improved. Since 2008 the Arctic Research Consortium of the United States (ARCUS) has conducted a seasonal forecasting contest in which the average Arctic sea ice extent for the month of September (the month of the annual extent minimum) is predicted from available forecasts in early June, July, and August. The competition is known as the Sea Ice Outlook (SIO) but recently came under the auspices of the Sea Ice Prediction Network (SIPN), and multi-agency funded project to evaluate the SIO. The forecasts are submitted based on modeling, statistical, and heuristic methods. Forecasts of Arctic sea ice extent from the GMAO are derived from seasonal prediction system of the NASA Goddard Earth Observing System model, version 5 (GEOS 5) coupled atmosphere and ocean general circulation model (AOGCM). The projections are made in order to understand the relative skill of the forecasting system and to determine the effects of future improvements to the system. This years prediction is for a September average Arctic ice extent of 5.030.41 million km2.

PAST Gateways (Palaeo-Arctic Spatial and Temporal Gateways): Introduction and overview

NASA Astrophysics Data System (ADS)

Ó Cofaigh, Colm; Briner, Jason P.; Kirchner, Nina; Lucchi, Renata G.; Meyer, Hanno; Kaufman, Darrell S.

2016-09-01

This special issue relates to the Second International Conference of the PAST Gateways (Palaeo-Arctic Spatial and Temporal Gateways) network which was held in Trieste, Italy in 2014. Twenty five papers are included and they address topics under four main themes: (1) The growth and decay of Arctic ice sheets; (2) Arctic sea ice and palaeoceanography; (3) Terrestrial Arctic environments and permafrost change; and (4) Holocene Arctic environmental change. Geographically the focus is circum-Arctic; the special issue includes detailed regional studies from Greenland, Scandinavia, Russia, and Arctic North America and the adjoining seas, as well as a series of synthesis-type, review papers on Fennoscandian Ice Sheet deglaciation and Holocene Arctic palaeo-climate change. The methodologies employed are diverse and include marine sediment core and geophysical investigations, terrestrial glacial geology and geomorphology, isotopic analysis of ground ice, palaeo-ecological analysis of lacustrine and terrestrial sedimentary archives, geochronology and numerical ice sheet modeling.

Growing Land-Sea Temperature Contrast and the Intensification of Arctic Cyclones

NASA Astrophysics Data System (ADS)

Day, Jonathan J.; Hodges, Kevin I.

2018-04-01

Cyclones play an important role in the coupled dynamics of the Arctic climate system on a range of time scales. Modeling studies suggest that storminess will increase in Arctic summer due to enhanced land-sea thermal contrast along the Arctic coastline, in a region known as the Arctic Frontal Zone (AFZ). However, the climate models used in these studies are poor at reproducing the present-day Arctic summer cyclone climatology and so their projections of Arctic cyclones and related quantities, such as sea ice, may not be reliable. In this study we perform composite analysis of Arctic cyclone statistics using AFZ variability as an analog for climate change. High AFZ years are characterized both by increased cyclone frequency and dynamical intensity, compared to low years. Importantly, the size of the response in this analog suggests that General Circulation Models may underestimate the response of Arctic cyclones to climate change, given a similar change in baroclinicity.

Midlatitude atmospheric responses to Arctic sensible heat flux anomalies in Community Climate Model, Version 4: Atmospheric Response to Arctic SHFs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mills, Catrin M.; Cassano, John J.; Cassano, Elizabeth N.

Possible linkages between Arctic sea ice loss and midlatitude weather are strongly debated in the literature. We analyze a coupled model simulation to assess the possibility of Arctic ice variability forcing a midlatitude response, ensuring consistency between atmosphere, ocean, and ice components. We work with weekly running mean daily sensible heat fluxes with the self-organizing map technique to identify Arctic sensible heat flux anomaly patterns and the associated atmospheric response, without the need of metrics to define the Arctic forcing or measure the midlatitude response. We find that low-level warm anomalies during autumn can build planetary wave patterns that propagatemore » downstream into the midlatitudes, creating robust surface cold anomalies in the eastern United States.« less

Late-Middle Quaternary lithostratigraphy and sedimentation patterns on the Alpha Ridge, central Arctic Ocean: Implications for Arctic climate variability on orbital time scales

NASA Astrophysics Data System (ADS)

Wang, Rujian; Polyak, Leonid; Xiao, Wenshen; Wu, Li; Zhang, Taoliang; Sun, Yechen; Xu, Xiaomei

2018-02-01

We use sediment cores collected by the Chinese National Arctic Research Expeditions from the Alpha Ridge to advance Quaternary stratigraphy and paleoceanographic reconstructions for the Arctic Ocean. Our cores show a good litho/biostratigraphic correlation to sedimentary records developed earlier for the central Arctic Ocean, suggesting a recovered stratigraphic range of ca. 0.6 Ma, suitable for paleoclimatic studies on orbital time scales. This stratigraphy was tested by correlating the stacked Alpha Ridge record of bulk XRF manganese, calcium and zirconium (Mn, Ca, Zr), to global stable-isotope (LR04-δ18O) and sea-level stacks and tuning to orbital parameters. Correlation results corroborate the applicability of presumed climate/sea-level controlled Mn variations in the Arctic Ocean for orbital tuning. This approach enables better understanding of the global and orbital controls on the Arctic climate. Orbital tuning experiments for our records indicate strong eccentricity (100-kyr) and precession (∼20-kyr) controls on the Arctic Ocean, probably implemented via glaciations and sea ice. Provenance proxies like Ca and Zr are shown to be unsuitable as orbital tuning tools, but useful as indicators of glacial/deglacial processes and circulation patterns in the Arctic Ocean. Their variations suggest an overall long-term persistence of the Beaufort Gyre circulation in the Alpha Ridge region. Some glacial intervals, e.g., MIS 6 and 4/3, are predominated by material presumably transported by the Transpolar Drift. These circulation shifts likely indicate major changes in the Arctic climatic regime, which yet need to be investigated. Overall, our results demonstrate applicability of XRF data to paleoclimatic studies of the Arctic Ocean.

The Arctic Boreal Vulnerability Experiment (ABoVE) 2017 Airborne Campaign

NASA Astrophysics Data System (ADS)

Miller, C. E.; Goetz, S. J.; Griffith, P. C.; Hoy, E.; Larson, E. K.; Hodkinson, D. J.; Hansen, C.; Woods, J.; Kasischke, E. S.; Margolis, H. A.

2017-12-01

The 2017 ABoVE Airborne Campaign (AAC) was one of the largest airborne experiments ever conducted by NASA's Earth Science Division. It involved nine aircraft in 17 deployments - more than 100 flights - between April and October and sampled over 4 million km2in Alaska and northwestern Canada. Many of these flights were coordinated with detailed, same-day ground-based measurements to link field-based, process-level studies with geospatial data products derived from satellite remote sensing. A major goal of the 2017 AAC was to collect data that spanned the critical intermediate space and time scales that are essential for a comprehensive understanding of scaling issues across the ABoVE Study Domain and extrapolation to the pan-Arctic. Additionally, the 2017 AAC provided unique opportunities to validate satellite and airborne remote sensing data for northern high latitude ecosystems, develop and advance fundamental remote sensing science, and explore scientific insights from innovative sensor combinations. The 2017 AAC science strategy coupled domain-wide sampling with L-band and P-band synthetic aperture radar (SAR), imaging spectroscopy (AVIRIS-NG), full waveform lidar (LVIS) and atmospheric carbon dioxide and methane with more spatially and temporally focused studies using Ka-band SAR (Ka-SPAR) and solar induced chlorophyll fluorescence (CFIS). Additional measurements were coordinated with the NEON Airborne Observing Platform, the ASCENDS instrument development suite, and the ATOM EV-S2 investigation. Targets of interest included the array of field sites operated by the ABoVE Science Team as well as the intensive sites operated by the DOE NGEE-Arctic team on the Seward Peninsula and in Barrow, NSF's LTER sites at Toolik Lake (North Slope) and Bonanza Creek (Interior Alaska), the Canadian Cold Regions Hydrology sites in the Arctic tundra near Trail Valley Creek NT, the Government of the Northwest Territories Slave River/Slave Delta watershed time series and numerous

Accelerated increase in the Arctic tropospheric warming events surpassing stratospheric warming events during winter: Accelerated Increase in Arctic Warming

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, S. -Y. Simon; Lin, Yen-Heng; Lee, Ming-Ying

In January 2016, a robust reversal of the Arctic Oscillation (AO) took place associated with a rapid tropospheric warming in the Arctic region; this was followed by the occurrence of a classic sudden stratospheric warming in March-April. The succession of these two distinct Arctic warming events provides a stimulating opportunity to examine their characteristics in terms of similarities and differences. Historical cases of these two types of Arctic warming were identified and validated based upon tropical linkages with the Madden-Julian Oscillation and El Niño as well as those documented in previous studies. Our results indicate a recent and accelerated increasemore » in the tropospheric warming type versus a flat trend in stratospheric warming type. Given that tropospheric warming events occur twice as fast than the stratospheric warming type, the noted increase in the former implies further intensification in midlatitude winter weather extremes similar to those experienced in early 2016. Forced simulations with an atmospheric general circulation model suggest that the reduced Arctic sea ice contributes to the observed increase in the tropospheric warming events and associated impact on the anomalously cold Siberia.« less

THE US MERCURY EMISSION INVENTORY FOR THE ARCTIC COUNCIL ACTION PLAN

EPA Science Inventory

The Arctic Council, having agreed to act to reduce exposures to a number of priority pollutants in the Arctic region, has initiated a mercury project via the Arctic Council Action Plan (ACAP). The project is led by the Danish EPA with a Steering Group from all eight Arctic count...

THE US MERCURY EMISSION INVENTORY FOR THE ARCTIC COUNCIL ACTION PLAN

EPA Science Inventory

The Arctic Council, having agreed to act to reduce exposures to a number of priority pollutants in the Arctic region, has initiated a mercury project via the Arctic Council Plan (ACAP). The project is being led by the Danish EPA with a Steering Group from all eight Arctic coun...

Effects of Arctic geoengineering on precipitation in the tropical monsoon regions

NASA Astrophysics Data System (ADS)

Nalam, Aditya; Bala, Govindasamy; Modak, Angshuman

2017-07-01

Arctic geoengineering wherein sunlight absorption is reduced only in the Arctic has been suggested as a remedial measure to counteract the on-going rapid climate change in the Arctic. Several modeling studies have shown that Arctic geoengineering can minimize Arctic warming but will shift the Inter-tropical Convergence Zone (ITCZ) southward, unless offset by comparable geoengineering in the Southern Hemisphere. In this study, we investigate and quantify the implications of this ITCZ shift due to Arctic geoengineering for the global monsoon regions using the Community Atmosphere Model version 4 coupled to a slab ocean model. A doubling of CO2 from pre-industrial levels leads to a warming of 6 K in the Arctic region and precipitation in the monsoon regions increases by up to 15%. In our Arctic geoengineering simulation which illustrates a plausible latitudinal distribution of the reduction in sunlight, an addition of sulfate aerosols (11 Mt) in the Arctic stratosphere nearly offsets the Arctic warming due to CO2 doubling but this shifts the ITCZ southward by 1.5° relative to the pre-industrial climate. The combined effect from this shift and the residual CO2-induced climate change in the tropics is a decrease/increase in annual mean precipitation in the Northern Hemisphere/Southern Hemisphere monsoon regions by up to -12/+17%. Polar geoengineering where sulfate aerosols are prescribed in both the Arctic (10 Mt) and Antarctic (8 Mt) nearly offsets the ITCZ shift due to Arctic geoengineering, but there is still a residual precipitation increase (up to 7%) in most monsoon regions associated with the residual CO2 induced warming in the tropics. The ITCZ shift due to our Global geoengineering simulation, where aerosols (20 Mt) are prescribed uniformly around the globe, is much smaller and the precipitation changes in most monsoon regions are within ±2% as the residual CO2-induced warming in the tropics is also much less than in Arctic and Polar geoengineering. Further

Microplastic contamination in benthic organisms from the Arctic and sub-Arctic regions.

PubMed

Fang, Chao; Zheng, Ronghui; Zhang, Yusheng; Hong, Fukun; Mu, Jingli; Chen, Mengyun; Song, Puqing; Lin, Longshan; Lin, Heshan; Le, Fengfeng; Bo, Jun

2018-06-14

The seafloor is recognized as one of the major sinks for microplastics (MPs). However, to date there have been no studies reported the MP contamination in benthic organisms from the Arctic and sub-Arctic regions. Therefore, this study provided the first data on the abundances and characteristics of MPs in a total of 413 dominant benthic organisms representing 11 different species inhabiting in the shelf of Bering and Chukchi Seas. The mean abundances of MP uptake by the benthos from all sites ranged from 0.02 to 0.46 items g -1 wet weight (ww) or 0.04-1.67 items individual -1 , which were lower values than those found in other regions worldwide. The highest value appeared at the northernmost site, implying that the sea ice and the cold current represent possible transport mediums. Interestingly, the predator A. rubens ingested the maximum quantities of MPs, suggesting that the trophic transfer of MPs through benthic food webs may play a critical role. Fibers constituted the major type (87%) in each species, followed by film (13%). The colors of fibers were classified as red (46%) and transparent (41%), and the film was all gray. The predominant composition was polyamide (PA) (46%), followed by polyethylene (PE) (23%), polyester (PET) (18%) and cellophane (CP) (13%). The most common sizes of MPs concentrated in the interval from 0.10 to 1.50 mm, and the mean size was 1.45 ± 0.13 mm. Further studies about the temporal trends and detrimental effects of MPs remain to be carried out in benthic organisms from the Arctic and sub-Arctic regions. Copyright © 2018 Elsevier Ltd. All rights reserved.

The future of Arctic benthos: Expansion, invasion, and biodiversity

NASA Astrophysics Data System (ADS)

Renaud, Paul E.; Sejr, Mikael K.; Bluhm, Bodil A.; Sirenko, Boris; Ellingsen, Ingrid H.

2015-12-01

One of the logical predictions for a future Arctic characterized by warmer waters and reduced sea-ice is that new taxa will expand or invade Arctic seafloor habitats. Specific predictions regarding where this will occur and which taxa are most likely to become established or excluded are lacking, however. We synthesize recent studies and conduct new analyses in the context of climate forecasts and a paleontological perspective to make concrete predictions as to relevant mechanisms, regions, and functional traits contributing to future biodiversity changes. Historically, a warmer Arctic is more readily invaded or transited by boreal taxa than it is during cold periods. Oceanography of an ice-free Arctic Ocean, combined with life-history traits of invading taxa and availability of suitable habitat, determine expansion success. It is difficult to generalize as to which taxonomic groups or locations are likely to experience expansion, however, since species-specific, and perhaps population-specific autecologies, will determine success or failure. Several examples of expansion into the Arctic have been noted, and along with the results from the relatively few Arctic biological time-series suggest inflow shelves (Barents and Chukchi Seas), as well as West Greenland and the western Kara Sea, are most likely locations for expansion. Apparent temperature thresholds were identified for characteristic Arctic and boreal benthic fauna suggesting strong potential for range constrictions of Arctic, and expansions of boreal, fauna in the near future. Increasing human activities in the region could speed introductions of boreal fauna and reduce the value of a planktonic dispersal stage. Finally, shelf regions are likely to experience a greater impact, and also one with greater potential consequences, than the deep Arctic basin. Future research strategies should focus on monitoring as well as compiling basic physiological and life-history information of Arctic and boreal taxa, and

Persistent maritime traffic monitoring for the Canadian Arctic

NASA Astrophysics Data System (ADS)

Ulmke, M.; Battistello, G.; Biermann, J.; Mohrdieck, C.; Pelot, R.; Koch, W.

2017-05-01

This paper presents results of the Canadian-German research project PASSAGES (Protection and Advanced Surveillance System for the Arctic: Green, Efficient, Secure)1 on an advanced surveillance system for safety and security of maritime operations in Arctic areas. The motivation for a surveillance system of the Northwest Passage is the projected growth of maritime traffic along Arctic sea routes and the need for securing Canada's sovereignty by controlling its arctic waters as well as for protecting the safety of international shipping and the intactness of the arctic marine environment. To ensure border security and to detect and prevent illegal activities it is necessary to develop a system for surveillance and reconnaissance that brings together all related means, assets, organizations, processes and structures to build one homogeneous and integrated system. The harsh arctic conditions require a new surveillance concept that fuses heterogeneous sensor data, contextual information, and available pre-processed surveillance data and combines all components to efficiently extract and provide the maximum available amount of information. The fusion of all these heterogeneous data and information will provide improved and comprehensive situation awareness for risk assessment and decision support of different stakeholder groups as governmental authorities, commercial users and Northern communities.

Future sea ice conditions and weather forecasts in the Arctic: Implications for Arctic shipping.

PubMed

Gascard, Jean-Claude; Riemann-Campe, Kathrin; Gerdes, Rüdiger; Schyberg, Harald; Randriamampianina, Roger; Karcher, Michael; Zhang, Jinlun; Rafizadeh, Mehrad

2017-12-01

The ability to forecast sea ice (both extent and thickness) and weather conditions are the major factors when it comes to safe marine transportation in the Arctic Ocean. This paper presents findings focusing on sea ice and weather prediction in the Arctic Ocean for navigation purposes, in particular along the Northeast Passage. Based on comparison with the observed sea ice concentrations for validation, the best performing Earth system models from the Intergovernmental Panel on Climate Change (IPCC) program (CMIP5-Coupled Model Intercomparison Project phase 5) were selected to provide ranges of potential future sea ice conditions. Our results showed that, despite a general tendency toward less sea ice cover in summer, internal variability will still be large and shipping along the Northeast Passage might still be hampered by sea ice blocking narrow passages. This will make sea ice forecasts on shorter time and space scales and Arctic weather prediction even more important.

Problems of Tectonics and Tectonic Evolution of the Arctic

NASA Astrophysics Data System (ADS)

Vernikovskiy, V. A.; Metelkin, D. V.; Matushkin, N. Y.; Vernikovskaya, A. E.; Chernova, A. I.; Mikhaltsov, N. E.

2017-12-01

The Arctic Ocean within Russia remains poorly investigated area, in particular to geological structures and the Arctic Ocean floor. Many researchers believe that the basements of the terranes, composing the Arctic shelf and continental slopes, are of the Precambrian age. It was assumed that the Arctic terranes formed the ancient paleocontinent of Arctida that broke up during rifting, whereas the separated plates and terranes accreted to the periphery of the Arctic Ocean at a later stage. However, geological, geochronological and paleomagnetic evidence to test this assumption has been insufficient. Recently, geological and geophysical studies have significantly increased, in particular to the structures of Eastern Arctic. For example, the New Siberian Islands Archipelago is one of key structures for understanding geology and evolution of the Arctic region. Additionally, several submerged structures containing fragments of continental crust, including the Lomonosov Ridge and the Mendeleev Rise, are identified within the Arctic Ocean and adjacent to the New Siberian Islands Archipelago. Here we present new geochronological and paleomagnetic data to refine the evolution of the Arctida paleocontinent. Our model implies existence of the two Arctidas during Late Precambrian - Late Paleozoic. The earlier Arctida-I was located near equator and connected with the continental margins of Laurentia, Baltica and Siberia within the supercontinent of Rodinia. The initiation of Arctida-I rifting is associated with breakup of Rodinia. As a result, small plates, including Svalbard, Kara, New Siberia Island and other terranes, were formed. We have reconstructed the main stages of further remobilization and global drift of these plates before Pangea assemblage. We assume that the later Arctida-II was located at the Pangean periphery in the temperate latitudes, and was also connected to the Laurentia, Baltica, and Siberia cratons. The breakup of the Arctida-II is suggested to have

The Immediacy of Arctic Change: New 2016-17 Extremes

NASA Astrophysics Data System (ADS)

Overland, J. E.; Kattsov, V.; Olsen, M. S.; Walsh, J. E.

2017-12-01

Additional recent observations add increased certainty to cryospheric Arctic changes, and trends are very likely to continue past mid-century. Observed and projected Arctic changes are large compared with those at mid-latitude, driven by greenhouse gas (GHG) increase and Arctic feedbacks. Sea ice has undergone a regime shift from mostly multi-year to first-year sea ice, and summer sea ice is likely to be esentially gone within the next few decades. Spring snow cover is decreasing, and Arctic greening is increasing, although somewhat variable. There are potential emerging impacts of Arctic change on mid-latitude weather and sea level rise. Model assessments under different future GHG concentration scenarios show that stabilizing global temperatures near 2° C compliant with Paris agreement could slow, but not halt further major changes in the Arctic before mid- 21st century; foreseeable Arctic temperature changes are 4-5° C for fall/winter by 2040-2050. Substantial and immediate mitigation reductions in GHG emissions (at least at the level of the RCP 4.5 emission scenario) should reduce the risk of further change for most cryospheric components after mid-century, and reduce the likelyhood of potential runaway loss of ice sheets and glaciers and their impact on sea level rise. Extreme winter 2016 Arctic temperatures and a large winter 2017 sea ice deficit demonstrate contemporary climate states outside the envelope of previous experience. While there is confidence in the sign of Arctic changes, recent observations increase uncertainty in projecting the rate for future real world scenarios. Do events return to mean conditions, represent irreversible changes, or contribute to accelerating trends beyond those provided by climate models? Such questions highlight the need for improved quantitative prediction of the cryosphere and its global impacts, crucial for adaptation actions and risk management at local to global scales.

Arctic curves in path models from the tangent method

NASA Astrophysics Data System (ADS)

Di Francesco, Philippe; Lapa, Matthew F.

2018-04-01

Recently, Colomo and Sportiello introduced a powerful method, known as the tangent method, for computing the arctic curve in statistical models which have a (non- or weakly-) intersecting lattice path formulation. We apply the tangent method to compute arctic curves in various models: the domino tiling of the Aztec diamond for which we recover the celebrated arctic circle; a model of Dyck paths equivalent to the rhombus tiling of a half-hexagon for which we find an arctic half-ellipse; another rhombus tiling model with an arctic parabola; the vertically symmetric alternating sign matrices, where we find the same arctic curve as for unconstrained alternating sign matrices. The latter case involves lattice paths that are non-intersecting but that are allowed to have osculating contact points, for which the tangent method was argued to still apply. For each problem we estimate the large size asymptotics of a certain one-point function using LU decomposition of the corresponding Gessel–Viennot matrices, and a reformulation of the result amenable to asymptotic analysis.

A Meteoric Water Budget for the Arctic Ocean

NASA Astrophysics Data System (ADS)

Alkire, Matthew B.; Morison, James; Schweiger, Axel; Zhang, Jinlun; Steele, Michael; Peralta-Ferriz, Cecilia; Dickinson, Suzanne

2017-12-01

A budget of meteoric water (MW = river runoff, net precipitation minus evaporation, and glacial meltwater) over four regions of the Arctic Ocean is constructed using a simple box model, regional precipitation-evaporation estimates from reanalysis data sets, and estimates of import and export fluxes derived from the literature with a focus on the 2003-2008 period. The budget indicates an approximate/slightly positive balance between MW imports and exports (i.e., no change in storage); thus, the observed total freshwater increase observed during this time period likely resulted primarily from changes in non-MW freshwater components (i.e., increases in sea ice melt or Pacific water and/or a decrease in ice export). Further, our analysis indicates that the MW increase observed in the Canada Basin resulted from a spatial redistribution of MW over the Arctic Ocean. Mean residence times for MW were estimated for the Western Arctic (5-7 years), Eastern Arctic (3-4 years), and Lincoln Sea (1-2 years). The MW content over the Siberian shelves was estimated (˜14,000 km3) based on a residence time of 3.5 years. The MW content over the entire Arctic Ocean was estimated to be ≥44,000 km3. The MW export through Fram Strait consisted mostly of water from the Eastern Arctic (3,237 ± 1,370 km3 yr-1) whereas the export through the Canadian Archipelago was nearly equally derived from both the Western Arctic (1,182 ± 534 km3 yr-1) and Lincoln Sea (972 ± 391 km3 yr-1).

Moball-Buoy Network: A Near-Real-Time Ground-Truth Distributed Monitoring System to Map Ice, Weather, Chemical Species, and Radiations, in the Arctic

NASA Astrophysics Data System (ADS)

Davoodi, F.; Shahabi, C.; Burdick, J.; Rais-Zadeh, M.; Menemenlis, D.

2014-12-01

The work had been funded by NASA HQ's office of Cryospheric Sciences Program. Recent observations of the Arctic have shown that sea ice has diminished drastically, consequently impacting the environment in the Arctic and beyond. Certain factors such as atmospheric anomalies, wind forces, temperature increase, and change in the distribution of cold and warm waters contribute to the sea ice reduction. However current measurement capabilities lack the accuracy, temporal sampling, and spatial coverage required to effectively quantify each contributing factor and to identify other missing factors. Addressing the need for new measurement capabilities for the new Arctic regime, we propose a game-changing in-situ Arctic-wide Distributed Mobile Monitoring system called Moball-buoy Network. Moball-buoy Network consists of a number of wind-propelled self-powered inflatable spheres referred to as Moball-buoys. The Moball-buoys are self-powered. They use their novel mechanical control and energy harvesting system to use the abundance of wind in the Arctic for their controlled mobility and energy harvesting. They are equipped with an array of low-power low-mass sensors and micro devices able to measure a wide range of environmental factors such as the ice conditions, chemical species wind vector patterns, cloud coverage, air temperature and pressure, electromagnetic fields, surface and subsurface water conditions, short- and long-wave radiations, bathymetry, and anthropogenic factors such as pollutions. The stop-and-go motion capability, using their novel mechanics, and the heads up cooperation control strategy at the core of the proposed distributed system enable the sensor network to be reconfigured dynamically according to the priority of the parameters to be monitored. The large number of Moball-buoys with their ground-based, sea-based, satellite and peer-to-peer communication capabilities would constitute a wireless mesh network that provides an interface for a global

Loss of sea ice in the Arctic.

PubMed

Perovich, Donald K; Richter-Menge, Jacqueline A

2009-01-01

The Arctic sea ice cover is in decline. The areal extent of the ice cover has been decreasing for the past few decades at an accelerating rate. Evidence also points to a decrease in sea ice thickness and a reduction in the amount of thicker perennial sea ice. A general global warming trend has made the ice cover more vulnerable to natural fluctuations in atmospheric and oceanic forcing. The observed reduction in Arctic sea ice is a consequence of both thermodynamic and dynamic processes, including such factors as preconditioning of the ice cover, overall warming trends, changes in cloud coverage, shifts in atmospheric circulation patterns, increased export of older ice out of the Arctic, advection of ocean heat from the Pacific and North Atlantic, enhanced solar heating of the ocean, and the ice-albedo feedback. The diminishing Arctic sea ice is creating social, political, economic, and ecological challenges.

Arctic patterned-ground ecosystems: A synthesis of field studies and models along a North American Arctic Transect

Treesearch

Walker D.A.; Romanovsky V.E.; Ping C.L.; Michaelson G.J.; Daanen R.P.; Shur Y.; Peterson R.A.; Krantz W.B.; Raynolds M.K.; William Gould; Grizelle Gonzalez; Nicolsky D.J.; Vonlanthen C.M.; Kade A.N.; Kuss P.; Kelley A.M.; Munger C.A.; Tarnocai C.T.; Matveyeva N.V.; Daniels F.J.A.

2008-01-01

Arctic landscapes have visually striking patterns of small polygons, circles, and hummocks. The linkages between the geophysical and biological components of these systems and their responses to climate changes are not well understood. The “Biocomplexity of Patterned Ground Ecosystems” project examined patterned-ground features (PGFs) in all five Arctic bioclimate...

Wildfires in northern Eurasia affect the budget of black carbon in the Arctic - a 12-year retrospective synopsis (2002-2013)

NASA Astrophysics Data System (ADS)

Evangeliou, N.; Balkanski, Y.; Hao, W. M.; Petkov, A.; Silverstein, R. P.; Corley, R.; Nordgren, B. L.; Urbanski, S. P.; Eckhardt, S.; Stohl, A.; Tunved, P.; Crepinsek, S.; Jefferson, A.; Sharma, S.; Nøjgaard, J. K.; Skov, H.

2016-06-01

In recent decades much attention has been given to the Arctic environment, where climate change is happening rapidly. Black carbon (BC) has been shown to be a major component of Arctic pollution that also affects the radiative balance. In the present study, we focused on how vegetation fires that occurred in northern Eurasia during the period of 2002-2013 influenced the budget of BC in the Arctic. For simulating the transport of fire emissions from northern Eurasia to the Arctic, we adopted BC fire emission estimates developed independently by GFED3 (Global Fire Emissions Database) and FEI-NE (Fire Emission Inventory - northern Eurasia). Both datasets were based on fire locations and burned areas detected by MODIS (Moderate resolution Imaging Spectroradiometer) instruments on NASA's (National Aeronautics and Space Administration) Terra and Aqua satellites. Anthropogenic sources of BC were adopted from the MACCity (Monitoring Atmospheric Composition and Climate and megacity Zoom for the Environment) emission inventory.During the 12-year period, an average area of 250 000 km2 yr-1 was burned in northern Eurasia (FEI-NE) and the global emissions of BC ranged between 8.0 and 9.5 Tg yr-1 (FEI-NE+MACCity). For the BC emitted in the Northern Hemisphere (based on FEI-NE+MACCity), about 70 % originated from anthropogenic sources and the rest from biomass burning (BB). Using the FEI-NE+MACCity inventory, we found that 102 ± 29 kt yr-1 BC was deposited in the Arctic (defined here as the area north of 67° N) during the 12 years simulated, which was twice as much as when using the MACCity inventory (56 ± 8 kt yr-1). The annual mass of BC deposited in the Arctic from all sources (FEI-NE in northern Eurasia, MACCity elsewhere) is significantly higher by about 37 % in 2009 (78 vs. 57 kt yr-1) to 181 % in 2012 (153 vs. 54 kt yr-1), compared to the BC deposited using just the MACCity emission inventory. Deposition of BC in the Arctic from BB sources in the Northern Hemisphere

Interact - Access to the Arctic

NASA Astrophysics Data System (ADS)

Johansson, M.; Callaghan, T. V.

2013-12-01

INTERACT is currently a network of 50 terrestrial research stations from all Arctic countries, but is still growing. The network was inaugurated in January 2011 when it received an EU 7th Framework award. INTERACT's main objective is to build capacity for identifying, understanding, predicting and responding to diverse environmental changes throughout the wide environmental and land-use envelopes of the Arctic. Implicit in this objective is the task to build capacity for monitoring, research, education and outreach. INTERACT is increasing access to the Arctic: 20 INTERACT research stations in Europe and Russia are offering Transnational Access and so far, 5600 person-days of access have been granted from the total of 10,000 offered. An INTERACT Station Managers' Forum facilitates a dialogue among station managers on subjects such as best practice in station management and standardised monitoring. The Station Managers' Forum has produced a unique 'one-stop-shop' for information from 45 research stations in an informative and attractive Station Catalogue that is available in hard copy and on the INTERACT web site (www.eu-interact.org). INTERACT also includes three joint research activities that are improving monitoring in remote, harsh environments and are making data capture and dissemination more efficient. Already, new equipment for measuring feedbacks from the land surface to the climate system has been installed at several locations, while best practices for sensor networking have been established. INTERACT networks with most of the high-level Arctic organisations: it includes AMAP and WWF as partners, is endorsed by IASC and CBMP, has signed MoUs with ISAC and the University of the Arctic, is a task within SAON, and contributes to the Cold Region community within GEO/GEOSS. INTERACT welcomes other interactions.

How well does your model capture the terrestrial ecosystem dynamics of the Arctic-Boreal Region?

NASA Astrophysics Data System (ADS)

Stofferahn, E.; Fisher, J. B.; Hayes, D. J.; Huntzinger, D. N.; Schwalm, C.

2016-12-01

The Arctic-Boreal Region (ABR) is a major source of uncertainties for terrestrial biosphere model (TBM) simulations. These uncertainties are precipitated by a lack of observational data from the region, affecting the parameterizations of cold environment processes in the models. Addressing these uncertainties requires a coordinated effort of data collection and integration of the following key indicators of the ABR ecosystem: disturbance, flora / fauna and related ecosystem function, carbon pools and biogeochemistry, permafrost, and hydrology. We are developing a model-data integration framework for NASA's Arctic Boreal Vulnerability Experiment (ABoVE), wherein data collection for the key ABoVE indicators is driven by matching observations and model outputs to the ABoVE indicators. The data are used as reference datasets for a benchmarking system which evaluates TBM performance with respect to ABR processes. The benchmarking system utilizes performance metrics to identify intra-model and inter-model strengths and weaknesses, which in turn provides guidance to model development teams for reducing uncertainties in TBM simulations of the ABR. The system is directly connected to the International Land Model Benchmarking (ILaMB) system, as an ABR-focused application.

Active molecular iodine photochemistry in the Arctic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raso, Angela R. W.; Custard, Kyle D.; May, Nathaniel W.

During springtime, the Arctic atmospheric boundary layer undergoes frequent rapid depletions in ozone and gaseous elemental mercury due to reactions with halogen atoms, influencing atmospheric composition and pollutant fate. Although bromine chemistry has been shown to initiate ozone depletion events, and it has long been hypothesized that iodine chemistry may contribute, no previous measurements of molecular iodine (I 2) have been reported in the Arctic. Iodine chemistry also contributes to atmospheric new particle formation and therefore cloud properties and radiative forcing. Here we present Arctic atmospheric I2 and snowpack iodide (I-) measurements, which were conducted near Utqiagvik, AK, in Februarymore » 2014. Using chemical ionization mass spectrometry, I2 was observed in the atmosphere at mole ratios of 0.3–1.0 ppt, and in the snowpack interstitial air at mole ratios up to 22 ppt under natural sunlit conditions and up to 35 ppt when the snowpack surface was artificially irradiated, suggesting a photochemical production mechanism. Further, snow meltwater I-measurements showed enrichments of up to ~1,900 times above the seawater ratio of I-/Na+, consistent with iodine activation and recycling. Modeling shows that observed I 2 levels are able to significantly increase ozone depletion rates, while also producing iodine monoxide (IO) at levels recently observed in the Arctic. These results emphasize the significance of iodine chemistry and the role of snowpack photochemistry in Arctic atmospheric composition, and imply that I 2 is likely a dominant source of iodine atoms in the Arctic.« less

Active molecular iodine photochemistry in the Arctic

DOE PAGES

Raso, Angela R. W.; Custard, Kyle D.; May, Nathaniel W.; ...

2017-09-05

During springtime, the Arctic atmospheric boundary layer undergoes frequent rapid depletions in ozone and gaseous elemental mercury due to reactions with halogen atoms, influencing atmospheric composition and pollutant fate. Although bromine chemistry has been shown to initiate ozone depletion events, and it has long been hypothesized that iodine chemistry may contribute, no previous measurements of molecular iodine (I 2) have been reported in the Arctic. Iodine chemistry also contributes to atmospheric new particle formation and therefore cloud properties and radiative forcing. Here we present Arctic atmospheric I 2 and snowpack iodide (I -) measurements, which were conducted near Utqiagvik, AK,more » in February 2014. Using chemical ionization mass spectrometry, I 2 was observed in the atmosphere at mole ratios of 0.3–1.0 ppt, and in the snowpack interstitial air at mole ratios up to 22 ppt under natural sunlit conditions and up to 35 ppt when the snowpack surface was artificially irradiated, suggesting a photochemical production mechanism. Further, snow meltwater I-measurements showed enrichments of up to ~1,900 times above the seawater ratio of I-/Na +, consistent with iodine activation and recycling. Modeling shows that observed I 2 levels are able to significantly increase ozone depletion rates, while also producing iodine monoxide (IO) at levels recently observed in the Arctic. Furthermore, these results emphasize the significance of iodine chemistry and the role of snowpack photochemistry in Arctic atmospheric composition, and imply that I 2 is likely a dominant source of iodine atoms in the Arctic.« less

Active molecular iodine photochemistry in the Arctic

NASA Astrophysics Data System (ADS)

Raso, Angela R. W.; Custard, Kyle D.; May, Nathaniel W.; Tanner, David; Newburn, Matt K.; Walker, Lawrence; Moore, Ronald J.; Huey, L. G.; Alexander, Liz; Shepson, Paul B.; Pratt, Kerri A.

2017-09-01

During springtime, the Arctic atmospheric boundary layer undergoes frequent rapid depletions in ozone and gaseous elemental mercury due to reactions with halogen atoms, influencing atmospheric composition and pollutant fate. Although bromine chemistry has been shown to initiate ozone depletion events, and it has long been hypothesized that iodine chemistry may contribute, no previous measurements of molecular iodine (I2) have been reported in the Arctic. Iodine chemistry also contributes to atmospheric new particle formation and therefore cloud properties and radiative forcing. Here we present Arctic atmospheric I2 and snowpack iodide (I-) measurements, which were conducted near Utqiaġvik, AK, in February 2014. Using chemical ionization mass spectrometry, I2 was observed in the atmosphere at mole ratios of 0.3-1.0 ppt, and in the snowpack interstitial air at mole ratios up to 22 ppt under natural sunlit conditions and up to 35 ppt when the snowpack surface was artificially irradiated, suggesting a photochemical production mechanism. Further, snow meltwater I- measurements showed enrichments of up to ˜1,900 times above the seawater ratio of I-/Na+, consistent with iodine activation and recycling. Modeling shows that observed I2 levels are able to significantly increase ozone depletion rates, while also producing iodine monoxide (IO) at levels recently observed in the Arctic. These results emphasize the significance of iodine chemistry and the role of snowpack photochemistry in Arctic atmospheric composition, and imply that I2 is likely a dominant source of iodine atoms in the Arctic.

Active Molecular Iodine Photochemistry in the Arctic

NASA Astrophysics Data System (ADS)

Raso, A. R. W.; Custard, K. D.; May, N.; Tanner, D.; Newburn, M. K.; Walker, L. R.; Moore, R.; Huey, L. G.; Alexander, M. L. L.; Shepson, P. B.; Pratt, K.

2017-12-01

During springtime, the Arctic atmospheric boundary layer undergoes frequent rapid depletions in ozone and gaseous elemental mercury due to reactions with halogen atoms, influencing atmospheric composition, and pollutant fate. While bromine chemistry has been shown to initiate ozone depletion events, and it has long been hypothesized that iodine chemistry may contribute, no previous measurements of molecular iodine (I2) have been reported in the Arctic. The presence of iodine chemistry is also expected to impact atmospheric new particle formation and therefore cloud properties and radiative forcing. Here we present the first Arctic I2 and snowpack iodide (I-) measurements, which were conducted near Utqiaġvik, AK in January and February 2014. Using chemical ionization mass spectrometry, I2 was observed in the boundary layer at molar ratios of 0.3 ppt and in the snowpack interstitial air at molar ratios up to 22 ppt under natural sunlit conditions and up to 35 ppt when the snowpack surface was artificially irradiated. I2 was not observed in the dark, suggesting a photochemical production mechanism. This is supported by our snowpack measurements of I-, which showed enrichment of up to 1900 times above the seawater ratio of I-/Na+. Simulations show even these low concentrations of I2 observed significantly increases ozone depletion rates, while also producing iodine monoxide at levels recently observed in the Arctic. These results emphasize the significance of iodine chemistry and the role of snowpack photochemistry in Arctic atmospheric composition, and imply that I2 is likely a dominant source of iodine atoms in the Arctic.

Active molecular iodine photochemistry in the Arctic.

PubMed

Raso, Angela R W; Custard, Kyle D; May, Nathaniel W; Tanner, David; Newburn, Matt K; Walker, Lawrence; Moore, Ronald J; Huey, L G; Alexander, Liz; Shepson, Paul B; Pratt, Kerri A

2017-09-19

During springtime, the Arctic atmospheric boundary layer undergoes frequent rapid depletions in ozone and gaseous elemental mercury due to reactions with halogen atoms, influencing atmospheric composition and pollutant fate. Although bromine chemistry has been shown to initiate ozone depletion events, and it has long been hypothesized that iodine chemistry may contribute, no previous measurements of molecular iodine (I 2 ) have been reported in the Arctic. Iodine chemistry also contributes to atmospheric new particle formation and therefore cloud properties and radiative forcing. Here we present Arctic atmospheric I 2 and snowpack iodide (I - ) measurements, which were conducted near Utqiaġvik, AK, in February 2014. Using chemical ionization mass spectrometry, I 2 was observed in the atmosphere at mole ratios of 0.3-1.0 ppt, and in the snowpack interstitial air at mole ratios up to 22 ppt under natural sunlit conditions and up to 35 ppt when the snowpack surface was artificially irradiated, suggesting a photochemical production mechanism. Further, snow meltwater I - measurements showed enrichments of up to ∼1,900 times above the seawater ratio of I - /Na + , consistent with iodine activation and recycling. Modeling shows that observed I 2 levels are able to significantly increase ozone depletion rates, while also producing iodine monoxide (IO) at levels recently observed in the Arctic. These results emphasize the significance of iodine chemistry and the role of snowpack photochemistry in Arctic atmospheric composition, and imply that I 2 is likely a dominant source of iodine atoms in the Arctic.

Arctic Ocean

NASA Technical Reports Server (NTRS)

Parkinson, Claire L.; Zukor, Dorothy J. (Technical Monitor)

2000-01-01

The Arctic Ocean is the smallest of the Earth's four major oceans, covering 14x10(exp 6) sq km located entirely within the Arctic Circle (66 deg 33 min N). It is a major player in the climate of the north polar region and has a variable sea ice cover that tends to increase its sensitivity to climate change. Its temperature, salinity, and ice cover have all undergone changes in the past several decades, although it is uncertain whether these predominantly reflect long-term trends, oscillations within the system, or natural variability. Major changes include a warming and expansion of the Atlantic layer, at depths of 200-900 m, a warming of the upper ocean in the Beaufort Sea, a considerable thinning (perhaps as high as 40%) of the sea ice cover, a lesser and uneven retreat of the ice cover (averaging approximately 3% per decade), and a mixed pattern of salinity increases and decreases.

Tropospheric ozone and aerosols measured by airborne lidar during the 1988 Arctic boundary layer experiment

NASA Technical Reports Server (NTRS)

Browell, Edward V.; Butler, Carolyn F.; Kooi, Susan A.

1991-01-01

Ozone (O3) and aerosol distributions were measured from an aircraft using a differential absorption lidar (DIAL) system as part of the 1988 NASA Global Tropospheric Experiment - Arctic Boundary Layer Experiment (ABLE-3A) to study the sources and sinks of gases and aerosols over the tundra regions of Alaska during the summer. The tropospheric O3 budget over the Arctic was found to be strongly influenced by stratospheric intrusions. Regions of low aerosol scattering and enhanced O3 mixing ratios were usually correlated with descending air from the upper troposphere or lower stratosphere. Several cases of continental polar air masses were examined during the experiment. The aerosol scattering associated with these air masses was very low, and the atmospheric distribution of aerosols was quite homogeneous for those air masses that had been transported over the ice for greater than or = 3 days. The transition in O3 and aerosol distributions from tundra to marine conditions was examined several times. The aerosol data clearly show an abrupt change in aerosol scattering properties within the mixed layer from lower values over the tundra to generally higher values over the water. The distinct differences in the heights of the mixed layers in the two regions was also readily apparent. Several cases of enhanced O3 were observed during ABLE-3 in conjunction with enhanced aerosol scattering in layers in the free atmosphere. Examples are presented of the large scale variations of O3 and aerosols observed with the airborne lidar system from near the surface to above the tropopause over the Arctic during ABLE-3.

Synthesizing International Understanding of Changes in the Arctic Hydrological System

NASA Astrophysics Data System (ADS)

Pundsack, J. W.; Vorosmarty, C. J.; Hinzman, L. D.

2009-12-01

There are several notable gaps in our current level of understanding of Arctic hydrological systems. At the same time, rapidly emerging data sets, technologies, and modeling resources provide us with an unprecedented opportunity to move substantially forward. The Arctic Community-Wide Hydrological Analysis and Monitoring Program (Arctic-CHAMP), funded by NSF/ARCSS, was established to initiate a major effort to improve our current monitoring of water cycle variables, and to foster collaboration with the many relevant U.S. and international arctic research initiatives. These projects, funded under ARCSS through the ‘Freshwater Integration (FWI) study’, links CHAMP, the Arctic/Subarctic Ocean Fluxes (ASOF) Programme, and SEARCH. As part of the overall synthesis and integration efforts of the NSF-ARCSS Freshwater Integration (FWI) study, the program carried-out a major International Synthesis Capstone Workshop in Fall 2009 as an International Polar Year (IPY) affiliated meeting. The workshop, "Synthesizing International Understanding of Changes in the Arctic Hydrological System,” was held 30 September to 4 October 2009 in Stockholm at the Beijer Auditorium of the Royal Swedish Academy. The workshop was sponsored by the NSF-ARCSS Arctic-CHAMP Science Management Office (City College of New York / Univ. of New Hampshire), the International Study of Arctic Change (ISAC), and the International Arctic Research Center (IARC; Univ. of Alaska Fairbanks). The overarching goals of the meeting were to stage a post-IPY lessons-learned workshop with co-equal numbers of FWI, IPY, and ICARP-II researchers, using insights from recent scientific findings, data, and strategies to afford synthesis. The workshop aimed to: (1) take stock of recent advances in our understanding of changes in the Arctic hydrological system; (2) identify key remaining research gaps / unanswered questions; and (3) gather insight on where to focus future research efforts/initiatives (nationally and

Ecotoxicological risk assessment of environmental pollutants in the Arctic.

PubMed

Brunström, B; Halldin, K

2000-03-15

Concentrations of such persistent organic pollutants (POPs) as polychlorinated biphenyls (PCBs) are high in certain Arctic animal species. The polar bear, Arctic fox, and glaucous gull may be exposed to PCB levels above lowest-observed-adverse-effect-level (LOAEL) values for adverse effects on reproduction in mammals and birds. However, the dioxin-like congeners seem to be major contributors to the reproductive effects of PCBs and the relative concentrations of these congeners are low in polar bears. Temporal trends for POPs in Arctic wildlife and the sensitivities of Arctic species to these compounds determine the risk for future adverse health effects.

Arctic shipping emissions inventories and future scenarios

NASA Astrophysics Data System (ADS)

Corbett, J. J.; Lack, D. A.; Winebrake, J. J.; Harder, S.; Silberman, J. A.; Gold, M.

2010-10-01

This paper presents 5 km×5 km Arctic emissions inventories of important greenhouse gases, black carbon and other pollutants under existing and future (2050) scenarios that account for growth of shipping in the region, potential diversion traffic through emerging routes, and possible emissions control measures. These high-resolution, geospatial emissions inventories for shipping can be used to evaluate Arctic climate sensitivity to black carbon (a short-lived climate forcing pollutant especially effective in accelerating the melting of ice and snow), aerosols, and gaseous emissions including carbon dioxide. We quantify ship emissions scenarios which are expected to increase as declining sea ice coverage due to climate change allows for increased shipping activity in the Arctic. A first-order calculation of global warming potential due to 2030 emissions in the high-growth scenario suggests that short-lived forcing of ~4.5 gigagrams of black carbon from Arctic shipping may increase global warming potential due to Arctic ships' CO2 emissions (~42 000 gigagrams) by some 17% to 78%. The paper also presents maximum feasible reduction scenarios for black carbon in particular. These emissions reduction scenarios will enable scientists and policymakers to evaluate the efficacy and benefits of technological controls for black carbon, and other pollutants from ships.

Nudging the Arctic Ocean to quantify Arctic sea ice feedbacks

NASA Astrophysics Data System (ADS)

Dekker, Evelien; Severijns, Camiel; Bintanja, Richard

2017-04-01

It is well-established that the Arctic is warming 2 to 3 time faster than rest of the planet. One of the great uncertainties in climate research is related to what extent sea ice feedbacks amplify this (seasonally varying) Arctic warming. Earlier studies have analyzed existing climate model output using correlations and energy budget considerations in order to quantify sea ice feedbacks through indirect methods. From these analyses it is regularly inferred that sea ice likely plays an important role, but details remain obscure. Here we will take a different and a more direct approach: we will keep the sea ice constant in a sensitivity simulation, using a state-of -the-art climate model (EC-Earth), applying a technique that has never been attempted before. This experimental technique involves nudging the temperature and salinity of the ocean surface (and possibly some layers below to maintain the vertical structure and mixing) to a predefined prescribed state. When strongly nudged to existing (seasonally-varying) sea surface temperatures, ocean salinity and temperature, we force the sea ice to remain in regions/seasons where it is located in the prescribed state, despite the changing climate. Once we obtain fixed' sea ice, we will run a future scenario, for instance 2 x CO2 with and without prescribed sea ice, with the difference between these runs providing a measure as to what extent sea ice contributes to Arctic warming, including the seasonal and geographical imprint of the effects.

Variability and trends in the Arctic Sea ice cover: Results from different techniques

NASA Astrophysics Data System (ADS)

Comiso, Josefino C.; Meier, Walter N.; Gersten, Robert

2017-08-01

Variability and trend studies of sea ice in the Arctic have been conducted using products derived from the same raw passive microwave data but by different groups using different algorithms. This study provides consistency assessment of four of the leading products, namely, Goddard Bootstrap (SB2), Goddard NASA Team (NT1), EUMETSAT Ocean and Sea Ice Satellite Application Facility (OSI-SAF 1.2), and Hadley HadISST 2.2 data in evaluating variability and trends in the Arctic sea ice cover. All four provide generally similar ice patterns but significant disagreements in ice concentration distributions especially in the marginal ice zone and adjacent regions in winter and meltponded areas in summer. The discrepancies are primarily due to different ways the four techniques account for occurrences of new ice and meltponding. However, results show that the different products generally provide consistent and similar representation of the state of the Arctic sea ice cover. Hadley and NT1 data usually provide the highest and lowest monthly ice extents, respectively. The Hadley data also show the lowest trends in ice extent and ice area at -3.88%/decade and -4.37%/decade, respectively, compared to an average of -4.36%/decade and -4.57%/decade for all four. Trend maps also show similar spatial distribution for all four with the largest negative trends occurring at the Kara/Barents Sea and Beaufort Sea regions, where sea ice has been retreating the fastest. The good agreement of the trends especially with updated data provides strong confidence in the quantification of the rate of decline in the Arctic sea ice cover.