Science.gov

Sample records for adverse climatic conditions

  1. Climate Change and Crop Exposure to Adverse Weather: Changes to Frost Risk and Grapevine Flowering Conditions

    PubMed Central

    Mosedale, Jonathan R.; Wilson, Robert J.; Maclean, Ilya M. D.

    2015-01-01

    The cultivation of grapevines in the UK and many other cool climate regions is expected to benefit from the higher growing season temperatures predicted under future climate scenarios. Yet the effects of climate change on the risk of adverse weather conditions or events at key stages of crop development are not always captured by aggregated measures of seasonal or yearly climates, or by downscaling techniques that assume climate variability will remain unchanged under future scenarios. Using fine resolution projections of future climate scenarios for south-west England and grapevine phenology models we explore how risks to cool-climate vineyard harvests vary under future climate conditions. Results indicate that the risk of adverse conditions during flowering declines under all future climate scenarios. In contrast, the risk of late spring frosts increases under many future climate projections due to advancement in the timing of budbreak. Estimates of frost risk, however, were highly sensitive to the choice of phenology model, and future frost exposure declined when budbreak was calculated using models that included a winter chill requirement for dormancy break. The lack of robust phenological models is a major source of uncertainty concerning the impacts of future climate change on the development of cool-climate viticulture in historically marginal climatic regions. PMID:26496127

  2. Effect of exposure to adverse climatic conditions on production in Manchega dairy sheep.

    PubMed

    Ramón, M; Díaz, C; Pérez-Guzman, M D; Carabaño, M J

    2016-07-01

    The present study aimed to examine the effects of exposure to adverse weather conditions on milk production to assess the thermotolerance capability of the Manchega breed, a dairy sheep reared in the Mediterranean area, and the extent of decline in production outside the thermal comfort zone. To achieve this purpose, we merged data from the official milk recording of the breed with weather information and used to describe the cold and heat stress response for production traits. Production data consisted of 1,094,804 test-day records from the first 3 lactations of 177,605 ewes gathered between years 2000 to 2010. For each production trait and climate variable, the thermal load production response was characterized by the estimation of cold and heat stress thresholds that define a thermoneutral zone and the slopes of production decay outside this thermoneutral zone. Overall, we observed a comfort region between 10 and 22°C for daily average temperature, 18 and 30°C for daily maximum temperature, and from 9 to 18 units for a temperature-humidity index (THI) for all traits. Decline in production due to cold stress effects was of a greater magnitude than heat stress effects, especially for milk yield. Production losses ranged between 7 and 16 and from 0.2 to 0.6g/d per °C (or THI unit) for milk and for fat and protein yields, respectively. For heat stress, the observed decline in production was of 1 to 5 and 0.1 to 0.3g/d per °C (or THI unit) above the threshold for milk yield and for fat and protein yields, respectively. Highly productive animals showed a narrower comfort zone and higher slopes of decay. The study of lagged effects of thermal load showed how consequences of cold and heat stress are already visible in the first hours after exposure. Thus, production losses were due mainly to climate conditions on the day of control and the day before, with conditions on the previous days having a smaller effect. Annual economic losses due to thermal (cold and heat

  3. Climate conditions in bedded confinement buildings

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Confinement buildings are utilized for finishing cattle to allow more efficient collection of animal waste and to buffer animals against adverse climatic conditions. Environmental data were obtained from a 29 m wide x 318 m long bedded confinement building with the long axis oriented east to west. T...

  4. Developing robust crop plants for sustaining growth and yield under adverse climatic changes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural production and quality are expected to suffer from adverse changes in climatic conditions, including global warming, and this will affect worldwide human and animal food security. Global warming has been shown to negatively impact crop yield and therefore will affect sustainability of a...

  5. HEPA Filter Performance under Adverse Conditions

    SciTech Connect

    Parsons, Michael; Hogancamp, Kristina; Alderman, Steven; Waggoner, Charles

    2007-07-01

    This study involved challenging nuclear grade high-efficiency particulate air (HEPA) filters under a variety of conditions that can arise in Department of Energy (DOE) applications such as: low or high RH, controlled and uncontrolled challenge, and filters with physically damaged media or seals (i.e., leaks). Reported findings correlate filter function as measured by traditional differential pressure techniques in comparison with simultaneous instrumental determination of up and down stream PM concentrations. Additionally, emission rates and failure signatures will be discussed for filters that have either failed or exceeded their usable lifetime. Significant findings from this effort include the use of thermocouples up and down stream of the filter housing to detect the presence of moisture. Also demonstrated in the moisture challenge series of tests is the effect of repeated wetting of the filter. This produces a phenomenon referred to as transient failure before the tensile strength of the media weakens to the point of physical failure. An evaluation of the effect of particle size distribution of the challenge aerosol on loading capacity of filters is also included. Results for soot and two size distributions of KCl are reported. Loading capacities for filters ranged from approximately 70 g of soot to nearly 900 g for the larger particle size distribution of KCl. (authors)

  6. Management of Cattle Exposed to Adverse Environmental Conditions.

    PubMed

    Mader, Terry L; Griffin, Dee

    2015-07-01

    During periods of adverse weather, optimum conditions for animal comfort and performance are compromised. Use of alternative supplementation programs need to be considered for livestock challenged by adverse environmental conditions. Use of additional water for consumption and cooling, shade, and/or alternative management strategies need to be considered to help livestock cope with heat stress. For animals reared outside during winter, strategies that increase animal space and environmental buffers need to be used to minimize effects of mud, wet conditions, and windchill. There are ample opportunities for livestock producers to enhance animal welfare and minimize the impact of environmental stress. PMID:26139190

  7. Word Learning under Adverse Listening Conditions: Context-Specific Recognition

    ERIC Educational Resources Information Center

    Creel, Sarah C.; Aslin, Richard N.; Tanenhaus, Michael K.

    2012-01-01

    Previous studies of word learning have presented the items to listeners under ideal conditions. Here we ask how listeners learn new vocabulary items under adverse listening conditions. Would listeners form acoustically-specific representations that incorporated the noise, base their representations on noise-free language knowledge, or both? To…

  8. Climatic Conditions in Classrooms.

    ERIC Educational Resources Information Center

    Kevan, Simon M.; Howes, John D.

    1980-01-01

    Presents an overview of research on the ways in which classroom thermal environment, lighting conditions, ion state, and electromagnetic and air pollution affect learning and the performance of students and teachers. (SJL)

  9. Quality of whey powders stored under adverse conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Whey protein concentrate powder (WPC) is exported by the U.S. and is included in emergency aid foods, but the bags sent overseas are usually stored without refrigeration and under elevated temperature and relative humidity (RH). The shelf life of WPC under adverse conditions must be known to preven...

  10. Uncertainty Comparison of Visual Sensing in Adverse Weather Conditions.

    PubMed

    Lo, Shi-Wei; Wu, Jyh-Horng; Chen, Lun-Chi; Tseng, Chien-Hao; Lin, Fang-Pang; Hsu, Ching-Han

    2016-01-01

    This paper focuses on flood-region detection using monitoring images. However, adverse weather affects the outcome of image segmentation methods. In this paper, we present an experimental comparison of an outdoor visual sensing system using region-growing methods with two different growing rules-namely, GrowCut and RegGro. For each growing rule, several tests on adverse weather and lens-stained scenes were performed, taking into account and analyzing different weather conditions with the outdoor visual sensing system. The influence of several weather conditions was analyzed, highlighting their effect on the outdoor visual sensing system with different growing rules. Furthermore, experimental errors and uncertainties obtained with the growing rules were compared. The segmentation accuracy of flood regions yielded by the GrowCut, RegGro, and hybrid methods was 75%, 85%, and 87.7%, respectively. PMID:27447642

  11. Mitigating the Adverse Association of Transportation and Climate

    NASA Astrophysics Data System (ADS)

    Snow, M. M.; Snow, R. K.

    2008-05-01

    The transportation sector consumes more than two-thirds of oil supplies in the U.S. each year and accounts for approximately one-third of U.S. carbon dioxide emissions. A draft of the Fourth U.S. Climate Action Report states that the current U.S. climate policy will culminate in the emission of 9.2 billion tons of greenhouse gases in 2020, which represents a 19 percent increase from 2000 levels. These higher levels of greenhouse gases contribute to rising temperatures while causing numerous transportation problems as abnormally hot days become more frequent and extreme. Asphalt roadways are subjected to softening while concrete highways undergo joint buckling creating hazardous conditions for motorists. Railroads tend to warp and buckle during significant heat events sometimes causing train derailments. Airports experiencing extreme temperatures are more likely to undergo high-density altitude conditions, which affect aircraft engine performance causing reduced lift, longer takeoff rolls, and runway closures. Increasing temperatures also have numerous indirect impacts on transportation and the associated infrastructure. Sea levels are projected to continue rising at an accelerated pace accompanied by higher storm surges and flooding. Consequently, seaports along with the connecting roadway and railway facilities will likely be inundated. Likewise, airports located along coasts are at risk of diminished operations due to rising waters and might require expensive protection measures in the near future. In light of such impacts and the finite supply of oil, myriad players in the transportation industry are researching conservation measures and alternative energy as well as the development of infrastructure and attitudes that promote emission reductions. This research examines a variety of practical and feasible solutions to decreasing greenhouse gases within the transportation sector based on the notion that as a result, new jobs would be created, billions of dollars

  12. Hierarchically nanotextured surfaces maintaining superhydrophobicity under severely adverse conditions

    NASA Astrophysics Data System (ADS)

    Maitra, Tanmoy; Antonini, Carlo; Auf der Mauer, Matthias; Stamatopoulos, Christos; Tiwari, Manish K.; Poulikakos, Dimos

    2014-07-01

    Superhydrophobic surfaces are highly desirable for a broad range of technologies and products affecting everyday life. Despite significant progress in recent years in understanding the principles of hydrophobicity, mostly inspired by surface designs found in nature, many man-made surfaces employ readily processable materials, ideal to demonstrate principles, but with little chance of survivability outside a very limited range of well-controlled environments. Here we focus on the rational development of robust, hierarchically nanostructured, environmentally friendly, metal-based (aluminum) superhydrophobic surfaces, which maintain their performance under severely adverse conditions. Based on their functionality, we superpose selected hydrophobic layers (i.e. self-assembled monolayers, thin films, or nanofibrous coatings) on hierarchically textured aluminum surfaces, collectively imparting high level robustness of superhydrophobicity under adverse conditions. These surfaces simultaneously exhibit chemical stability, mechanical durability and droplet impalement resistance. They impressively maintained their superhydrophobicity after exposure to severely adverse chemical environments like strong alkaline (pH ~ 9-10), acidic (pH ~ 2-3), and ionic solutions (3.5 weight% of sodium chloride), and could simultaneously resist water droplet impalement up to an impact velocity of 3.2 m s-1 as well as withstand standard mechanical durability tests.Superhydrophobic surfaces are highly desirable for a broad range of technologies and products affecting everyday life. Despite significant progress in recent years in understanding the principles of hydrophobicity, mostly inspired by surface designs found in nature, many man-made surfaces employ readily processable materials, ideal to demonstrate principles, but with little chance of survivability outside a very limited range of well-controlled environments. Here we focus on the rational development of robust, hierarchically

  13. Perceptual Learning of Speech under Optimal and Adverse Conditions

    PubMed Central

    Zhang, Xujin; Samuel, Arthur G.

    2014-01-01

    Humans have a remarkable ability to understand spoken language despite the large amount of variability in speech. Previous research has shown that listeners can use lexical information to guide their interpretation of atypical sounds in speech (Norris, McQueen, & Cutler, 2003). This kind of lexically induced perceptual learning enables people to adjust to the variations in utterances due to talker-specific characteristics, such as individual identity and dialect. The current study investigated perceptual learning in two optimal conditions: conversational speech (Experiment 1) vs. clear speech (Experiment 2), and three adverse conditions: noise (Experiment 3a) vs. two cognitive loads (Experiments 4a & 4b). Perceptual learning occurred in the two optimal conditions and in the two cognitive load conditions, but not in the noise condition. Furthermore, perceptual learning occurred only in the first of two sessions for each participant, and only for atypical /s/ sounds and not for atypical /f/ sounds. This pattern of learning and non-learning reflects a balance between flexibility and stability that the speech system must have to deal with speech variability in the diverse conditions that speech is encountered. PMID:23815478

  14. Speech perception with tactile support in adverse listening conditions

    NASA Astrophysics Data System (ADS)

    Drullman, Rob; Bronkhorst, Adelbert W.

    2002-05-01

    Since long, different methods of vibrotactile stimulation have been used as an aid for speech perception by some people with severe hearing impairment. The fact that experiments have shown (limited) benefits proves that tactile information can indeed give some support. In our research program on multimodal interfaces, we wondered if normal hearing listeners could benefit from tactile information when speech was presented in adverse listening conditions. Therefore, we set up a pilot experiment with a male speaker against a background of one, two, four or eight competing male speakers or speech noise. Sound was presented diotically to the subjects and the speech-reception threshold (SRT) for short sentences was measured. The temporal envelope (0-30 Hz) of the speech signal was computed in real time and led to the tactile transducer (MiniVib), which was fixed to the index finger. First results show a significant drop in SRT of about 3 dB when using tactile stimulation in the condition of one competing speaker. In the other conditions no significant effects were found, but there is a trend of a decrease of the SRT when tactile information is given. We will discuss the results of further experiments.

  15. Risk of Adverse Cognitive or Behavioral Conditions and Psychiatric Disorders

    NASA Technical Reports Server (NTRS)

    Slack, Kelley J.; Schneiderman, Jason S.; Leveton, Lauren B.; Whitmire, Alexandra M.; Picano, James J.

    2015-01-01

    The NASA commitment to human space flight includes continuing to fly astronauts on the ISS until it is decommissioned as well as possibly returning astronauts to the moon or having astronauts venture to an asteroid or Mars. As missions leave low Earth orbit and explore deeper space, BHP supports and conducts research to enable a risk posture that considers the risk of adverse cognitive or behavioral conditions and psychiatric disorders “acceptable given mitigations,” for pre-, in, and post-flight.The Human System Risk Board (HSRB) determines the risk of various mission scenarios using a likelihood (per person per year) by consequences matrix examining those risks across two categories—long term health and operational (within mission). Colors from a stoplight signal are used by HSRB and quickly provide a means of assessing overall perceived risk for a particular mission scenario. Risk associated with the current six month missions on the ISS are classified as “accepted with monitoring” while planetary missions, such as a mission to Mars, are recognized to be a “red” risk that requires mitigation to ensure mission success.Currently, the HSRB deems that the risk of adverse cognitive or behavioral conditions and psychiatric outcomes requires mitigation for planetary missions owing to long duration isolation and radiation exposure (see Table 1). While limited research evidence exists from spaceflight, it is well known anecdotally that the shift from the two week shuttle missions to the six month ISS missions renders the psychological stressors of space as more salient over longer duration missions. Shuttle astronauts were expected just to tolerate any stressors that arose during their mission and were successful at doing so (Whitmire et al, 2013). While it is possible to deal with stressors such as social isolation and to live with incompatible crewmembers for two weeks on shuttle, “ignoring it” is much less likely to be a successful coping mechanism

  16. Transport Across Chloroplast Membranes: Optimizing Photosynthesis for Adverse Environmental Conditions.

    PubMed

    Pottosin, Igor; Shabala, Sergey

    2016-03-01

    Chloroplasts are central to solar light harvesting and photosynthesis. Optimal chloroplast functioning is vitally dependent on a very intensive traffic of metabolites and ions between the cytosol and stroma, and should be attuned for adverse environmental conditions. This is achieved by an orchestrated regulation of a variety of transport systems located at chloroplast membranes such as porines, solute channels, ion-specific cation and anion channels, and various primary and secondary active transport systems. In this review we describe the molecular nature and functional properties of the inner and outer envelope and thylakoid membrane channels and transporters. We then discuss how their orchestrated regulation affects thylakoid structure, electron transport and excitation energy transfer, proton-motive force partition, ion homeostasis, stromal pH regulation, and volume regulation. We link the activity of key cation and anion transport systems with stress-specific signaling processes in chloroplasts, and discuss how these signals interact with the signals generated in other organelles to optimize the cell performance, with a special emphasis on Ca(2+) and reactive oxygen species signaling. PMID:26597501

  17. Present weather and climate: evolving conditions

    USGS Publications Warehouse

    Hoerling, Martin P; Dettinger, Michael; Wolter, Klaus; Lukas, Jeff; Eischeid, Jon K.; Nemani, Rama; Liebmann, Brant; Kunkel, Kenneth E.

    2013-01-01

    This chapter assesses weather and climate variability and trends in the Southwest, using observed climate and paleoclimate records. It analyzes the last 100 years of climate variability in comparison to the last 1,000 years, and links the important features of evolving climate conditions to river flow variability in four of the region’s major drainage basins. The chapter closes with an assessment of the monitoring and scientific research needed to increase confidence in understanding when climate episodes, events, and phenomena are attributable to human-caused climate change.

  18. 75 FR 8353 - Waiver of Filing Deadline Due to Adverse Weather Conditions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-24

    ... COMMISSION Waiver of Filing Deadline Due to Adverse Weather Conditions February 16, 2010. AGENCY: Federal Communications Commission. ACTION: Notice. SUMMARY: Due to adverse weather conditions, the Federal Communications..., February 11, 2010. In recognition of the numerous closings and disruptions caused by the weather in...

  19. Climate Conditioning for the Learning Environment.

    ERIC Educational Resources Information Center

    Perkins and Will, Architects, Chicago, IL.

    Discusses heating, cooling, and ventilation for the classroom in relationship to students' learning abilities. It is designed to assist school boards, administrators, architects and engineers in understanding the beneficial effects of total climate control, and in evaluating the climate conditioning systems available for schools. Discussion…

  20. Bill E. Kunkle Interdisciplinary Beef Symposium: Animal welfare concerns for cattle exposed to adverse environmental conditions.

    PubMed

    Mader, T L

    2014-12-01

    reared outside during the winter, strategies that increase animal space and environmental buffers need to be employed to minimize effects of mud, wet conditions, and wind chill. The above-mentioned weather events suggest that there are ample opportunities for livestock producers to enhance animal welfare and minimize impact of environmental stress. Caretakers need a greater understanding of animal responses to weather challenges to help animals cope with adverse climatic conditions. PMID:25414102

  1. 7 CFR 760.203 - Eligible losses, adverse weather, and other loss conditions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 7 2012-01-01 2012-01-01 false Eligible losses, adverse weather, and other loss... for Livestock, Honeybees, and Farm-Raised Fish Program § 760.203 Eligible losses, adverse weather, and... weather or eligible loss condition, as determined by the Deputy Administrator, (including, but not...

  2. 7 CFR 760.203 - Eligible losses, adverse weather, and other loss conditions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 7 2013-01-01 2013-01-01 false Eligible losses, adverse weather, and other loss... for Livestock, Honeybees, and Farm-Raised Fish Program § 760.203 Eligible losses, adverse weather, and... weather or eligible loss condition, as determined by the Deputy Administrator, (including, but not...

  3. 7 CFR 760.203 - Eligible losses, adverse weather, and other loss conditions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false Eligible losses, adverse weather, and other loss... for Livestock, Honeybees, and Farm-Raised Fish Program § 760.203 Eligible losses, adverse weather, and... weather or eligible loss condition, as determined by the Deputy Administrator, (including, but not...

  4. 7 CFR 760.203 - Eligible losses, adverse weather, and other loss conditions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Eligible losses, adverse weather, and other loss... for Livestock, Honeybees, and Farm-Raised Fish Program § 760.203 Eligible losses, adverse weather, and... weather or eligible loss condition, as determined by the Deputy Administrator, (including, but not...

  5. Fluorescence parameters of leaves of trees and shrubs during period of adverse weather conditions in Krasnoyarsk

    NASA Astrophysics Data System (ADS)

    Zavorueva, E. N.; Zavoruev, V. V.

    2015-11-01

    The effect of adverse weather conditions (AWC) on the fluorescence parameters of leaves Prinsepia sinensis, Amelanchier florida, Crataegus chlorocarca is obtained. However, significant changes in the fluorescence of the leaves of Acer negundo, Betula pendula under AWC were not observed.

  6. Freezing of Martian streams under climatic conditions

    NASA Technical Reports Server (NTRS)

    Carr, M. H.

    1984-01-01

    The valley networks of Mars are widely believed to have formed at a time when climatic conditions on the planet were significantly different from those that currently prevail. This view arises from the following observations: (1) the valleys form integrated branching networks which suggests fluid drainage, and water is the most plausible fluid, (2) the present atmosphere contains only minute amounts of water, (3) the networks appear to be more akin to terrestrial valleys that are eroded by streams of modest discharges than features that form by catastrophic floods, and (4) small streams of water will rapidly freeze under present climatic conditions. Climatic conditions at the time of formation of the valleys are studied based on the assumption that they were cut by running water.

  7. ACCEPT: Introduction of the Adverse Condition and Critical Event Prediction Toolbox

    NASA Technical Reports Server (NTRS)

    Martin, Rodney A.; Santanu, Das; Janakiraman, Vijay Manikandan; Hosein, Stefan

    2015-01-01

    The prediction of anomalies or adverse events is a challenging task, and there are a variety of methods which can be used to address the problem. In this paper, we introduce a generic framework developed in MATLAB (sup registered mark) called ACCEPT (Adverse Condition and Critical Event Prediction Toolbox). ACCEPT is an architectural framework designed to compare and contrast the performance of a variety of machine learning and early warning algorithms, and tests the capability of these algorithms to robustly predict the onset of adverse events in any time-series data generating systems or processes.

  8. Mapping climate conditions with materials corrosion

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    The world's first comprehensive materials corrosion mapping system can predict the effects that climatic conditions have on the life cycle of products ranging from automobiles to bridges, according to Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO) and the Australian Industrial Galvanizers Corporation. Both jointly announced the system on 14 November.The mapping system, which incorporates conditions such as moisture, salinity pollution, and prevailing winds, can predict the corrosion of materials in any part of Australia, they said. Ivan Cole of CSIRO Materials Engineering said the mapping system even takes into account durability factors impacting on greenhouse gas contributions and soil conditions, making it a unique tool for Australian industry.

  9. Health Monitoring and Management for Manufacturing Workers in Adverse Working Conditions.

    PubMed

    Xu, Xiaoya; Zhong, Miao; Wan, Jiafu; Yi, Minglun; Gao, Tiancheng

    2016-10-01

    In adverse working conditions, environmental parameters such as metallic dust, noise, and environmental temperature, directly affect the health condition of manufacturing workers. It is therefore important to implement health monitoring and management based on important physiological parameters (e.g., heart rate, blood pressure, and body temperature). In recent years, new technologies, such as body area networks, cloud computing, and smart clothing, have allowed the improvement of the quality of services. In this article, we first give five-layer architecture for health monitoring and management of manufacturing workers. Then, we analyze the system implementation process, including environmental data processing, physical condition monitoring and system services and management, and present the corresponding algorithms. Finally, we carry out an evaluation and analysis from the perspective of insurance and compensation for manufacturing workers in adverse working conditions. The proposed scheme will contribute to the improvement of workplace conditions, realize health monitoring and management, and protect the interests of manufacturing workers. PMID:27624491

  10. Comprehension of Familiar and Unfamiliar Native Accents under Adverse Listening Conditions

    ERIC Educational Resources Information Center

    Adank, Patti; Evans, Bronwen G.; Stuart-Smith, Jane; Scott, Sophie K.

    2009-01-01

    This study aimed to determine the relative processing cost associated with comprehension of an unfamiliar native accent under adverse listening conditions. Two sentence verification experiments were conducted in which listeners heard sentences at various signal-to-noise ratios. In Experiment 1, these sentences were spoken in a familiar or an…

  11. Adverse Pregnancy Conditions, Infertility, and Future Cardiovascular Risk: Implications for Mother and Child

    PubMed Central

    Park, Ki; Wei, Janet; Minissian, Margo; Merz, C. Noel Bairey

    2016-01-01

    Adverse pregnancy conditions in women are common and have been associated with adverse cardiovascular and metabolic outcomes such as myocardial infarction and stroke. As risk stratification in women is often suboptimal, recognition of non-traditional risk factors such as hypertensive disorders of pregnancy and premature delivery has become increasingly important. Additionally, such conditions may also increase the risk of cardiovascular disease in the children of afflicted women. In this review, we aim to highlight these conditions, along with infertility, and the association between such conditions and various cardiovascular outcomes and related maternal risk along with potential translation of risk to offspring. We will also discuss proposed mechanisms driving these associations as well as potential opportunities for screening and risk modification. PMID:26037616

  12. Causal Factors and Adverse Conditions of Aviation Accidents and Incidents Related to Integrated Resilient Aircraft Control

    NASA Technical Reports Server (NTRS)

    Reveley, Mary S.; Briggs, Jeffrey L.; Evans, Joni K.; Sandifer, Carl E.; Jones, Sharon Monica

    2010-01-01

    The causal factors of accidents from the National Transportation Safety Board (NTSB) database and incidents from the Federal Aviation Administration (FAA) database associated with loss of control (LOC) were examined for four types of operations (i.e., Federal Aviation Regulation Part 121, Part 135 Scheduled, Part 135 Nonscheduled, and Part 91) for the years 1988 to 2004. In-flight LOC is a serious aviation problem. Well over half of the LOC accidents included at least one fatality (80 percent in Part 121), and roughly half of all aviation fatalities in the studied time period occurred in conjunction with LOC. An adverse events table was updated to provide focus to the technology validation strategy of the Integrated Resilient Aircraft Control (IRAC) Project. The table contains three types of adverse conditions: failure, damage, and upset. Thirteen different adverse condition subtypes were gleaned from the Aviation Safety Reporting System (ASRS), the FAA Accident and Incident database, and the NTSB database. The severity and frequency of the damage conditions, initial test conditions, and milestones references are also provided.

  13. Assessment of the State of the Art of Flight Control Technologies as Applicable to Adverse Conditions

    NASA Technical Reports Server (NTRS)

    Reveley, Mary s.; Briggs, Jeffrey L.; Leone, Karen M.; Kurtoglu, Tolga; Withrow, Colleen A.

    2010-01-01

    Literature from academia, industry, and other Government agencies was surveyed to assess the state of the art in current Integrated Resilient Aircraft Control (IRAC) aircraft technologies. Over 100 papers from 25 conferences from the time period 2004 to 2009 were reviewed. An assessment of the general state of the art in adaptive flight control is summarized first, followed by an assessment of the state of the art as applicable to 13 identified adverse conditions. Specific areas addressed in the general assessment include flight control when compensating for damage or reduced performance, retrofit software upgrades to flight controllers, flight control through engine response, and finally test and validation of new adaptive controllers. The state-of-the-art assessment applicable to the adverse conditions include technologies not specifically related to flight control, but may serve as inputs to a future flight control algorithm. This study illustrates existing gaps and opportunities for additional research by the NASA IRAC Project

  14. Algorithms for contours depicting static electric fields during adverse weather conditions

    NASA Technical Reports Server (NTRS)

    Rompala, John T.

    1991-01-01

    A flexible and functional analytical tool is developed for the study of electric fields during adverse weather conditions. This tool is designed for use by members of the Atmospheric Science Group as part of their overall effort to appraise environmental conditions during these situations. It is also used to illustrate approaches open to those interested in the study of the physics of ambient electric field phenomena. Computer resources of KSC are coordinated with original software to produce contour interpretations of electric field data available from a grid of field mills spanning the region. Three model algorithms are presented and examples are given illustrating the system design, flexibility, and utility.

  15. Evaluation of adaptive dynamic range optimization in adverse listening conditions for cochlear implants

    PubMed Central

    Ali, Hussnain; Hazrati, Oldooz; Tobey, Emily A.; Hansen, John H. L

    2014-01-01

    The aim of this study is to investigate the effect of Adaptive Dynamic Range Optimization (ADRO) on speech identification for cochlear implant (CI) users in adverse listening conditions. In this study, anechoic quiet, noisy, reverberant, noisy reverberant, and reverberant noisy conditions are evaluated. Two scenarios are considered when modeling the combined effects of reverberation and noise: (a) noise is added to the reverberant speech, and (b) noisy speech is reverberated. CI users were tested in different listening environments using IEEE sentences presented at 65 dB sound pressure level. No significant effect of ADRO processing on speech intelligibility was observed. PMID:25190428

  16. Evaluation of adaptive dynamic range optimization in adverse listening conditions for cochlear implants.

    PubMed

    Ali, Hussnain; Hazrati, Oldooz; Tobey, Emily A; Hansen, John H L

    2014-09-01

    The aim of this study is to investigate the effect of Adaptive Dynamic Range Optimization (ADRO) on speech identification for cochlear implant (CI) users in adverse listening conditions. In this study, anechoic quiet, noisy, reverberant, noisy reverberant, and reverberant noisy conditions are evaluated. Two scenarios are considered when modeling the combined effects of reverberation and noise: (a) noise is added to the reverberant speech, and (b) noisy speech is reverberated. CI users were tested in different listening environments using IEEE sentences presented at 65 dB sound pressure level. No significant effect of ADRO processing on speech intelligibility was observed. PMID:25190428

  17. Some effects of adverse weather conditions on performance of airplane antiskid braking systems

    NASA Technical Reports Server (NTRS)

    Horne, W. B.; Mccarty, J. L.; Tanner, J. A.

    1976-01-01

    The performance of current antiskid braking systems operating under adverse weather conditions was analyzed in an effort to both identify the causes of locked-wheel skids which sometimes occur when the runway is slippery and to find possible solutions to this operational problem. This analysis was made possible by the quantitative test data provided by recently completed landing research programs using fully instrumented flight test airplanes and was further supported by tests performed at the Langley aircraft landing loads and traction facility. The antiskid system logic for brake control and for both touchdown and locked-wheel protection is described and its response behavior in adverse weather is discussed in detail with the aid of available data. The analysis indicates that the operational performance of the antiskid logic circuits is highly dependent upon wheel spin-up acceleration and can be adversely affected by certain pilot braking inputs when accelerations are low. Normal antiskid performance is assured if the tire-to-runway traction is sufficient to provide high wheel spin-up accelerations or if the system is provided a continuous, accurate ground speed reference. The design of antiskid systems is complicated by the necessity for tradeoffs between tire braking and cornering capabilities, both of which are necessary to provide safe operations in the presence of cross winds, particularly under slippery runway conditions.

  18. Risk of Adverse Cognitive or Behavioral Conditions and Psychiatric Disorders: Evidence Report

    NASA Technical Reports Server (NTRS)

    Slack, Kelley J.; Williams, Thomas J.; Schneiderman, Jason S.; Whitmire, Alexandra M.; Picano, James J.; Leveton, Lauren B.; Schmidt, Lacey L.; Shea, Camille

    2016-01-01

    In April 2010, President Obama declared a space pioneering goal for the United States in general and NASA in particular. "Fifty years after the creation of NASA, our goal is no longer just a destination to reach. Our goal is the capacity for people to work and learn and operate and live safely beyond the Earth for extended periods of time, ultimately in ways that are more sustainable and even indefinite." Thus NASA's Strategic Objective 1.1 emerged as "expand human presence into the solar system and to the surface of Mars to advance exploration, science, innovation, benefits to humanity, and international collaboration" (NASA 2015b). Any space flight, be it of long or short duration, occurs in an extreme environment that has unique stressors. Even with excellent selection methods, the potential for behavioral problems among space flight crews remain a threat to mission success. Assessment of factors that are related to behavioral health can help minimize the chances of distress and, thus, reduce the likelihood of adverse cognitive or behavioral conditions and psychiatric disorders arising within a crew. Similarly, countermeasures that focus on prevention and treatment can mitigate the cognitive or behavioral conditions that, should they arise, would impact mission success. Given the general consensus that longer duration, isolation, and confined missions have a greater risk for behavioral health ensuring crew behavioral health over the long term is essential. Risk, which within the context of this report is assessed with respect to behavioral health and performance, is addressed to deter development of cognitive and behavioral degradations or psychiatric conditions in space flight and analog populations, and to monitor, detect, and treat early risk factors, predictors and other contributing factors. Based on space flight and analog evidence, the average incidence rate of an adverse behavioral health event occurring during a space mission is relatively low for the

  19. Adverse psychosocial working conditions and minor psychiatric disorders among bank workers

    PubMed Central

    2010-01-01

    Background In most countries, the financial service sector has undergone great organizational changes in the past decades, with potential negative impact on bank workers' mental health. The aim of this paper is to estimate the prevalence of minor psychiatric disorders (MPD) among Brazilian bank workers and to investigate whether they are associated with an adverse psychosocial working environment. Methods A cross-sectional study of a random sample of 2,500 workers in a Brazilian state bank in 2008. The presence of MPD was determined by the General Health Questionnaire.(GHQ). Psychosocial work conditions were assessed by means of the Effort-Reward Imbalance (ERI) and Job Content Questionnaire (JCQ). The presence and magnitude of the independent associations between MPD and adverse psychosocial working conditions were determined by Prevalence Ratios, obtained by Poisson regression. Results From 2,337 eligible workers, 88% participated. The prevalence of MPD was greater among women (45% vs. 41%; p > 0.05). In the multivariate analysis, the prevalence of MPD was twice as high among bank workers exposed to high psychological demand and low control at work and under high effort and low reward working conditions. The lack of social support at work and the presence of over-commitment were also associated with higher prevalence of MPD. A negative interaction effect was found between over-commitment and effort-reward imbalance. Conclusion The prevalence of MPD is high among bank workers. The results reinforce the association between MPD and adverse psychosocial working conditions, assessed by the JCQ and ERI models. The direction of the interaction observed between over-commitment and ERI was contrary to what was expected. PMID:21062496

  20. Population Trends of Central European Montane Birds Provide Evidence for Adverse Impacts of Climate Change on High-Altitude Species

    PubMed Central

    Flousek, Jiří; Telenský, Tomáš; Hanzelka, Jan; Reif, Jiří

    2015-01-01

    Climate change is among the most important global threats to biodiversity and mountain areas are supposed to be under especially high pressure. Although recent modelling studies suggest considerable future range contractions of montane species accompanied with increased extinction risk, data allowing to test actual population consequences of the observed climate changes and identifying traits associated to their adverse impacts are very scarce. To fill this knowledge gap, we estimated long-term population trends of montane birds from 1984 to 2011 in a central European mountain range, the Giant Mountains (Krkonoše), where significant warming occurred over this period. We then related the population trends to several species' traits related to the climate change effects. We found that the species breeding in various habitats at higher altitudes had more negative trends than species breeding at lower altitudes. We also found that the species moved upwards as a response to warming climate, and these altitudinal range shifts were associated with more positive population trends at lower altitudes than at higher altitudes. Moreover, long-distance migrants declined more than residents or species migrating for shorter distances. Taken together, these results indicate that the climate change, besides other possible environmental changes, already influences populations of montane birds with particularly adverse impacts on high-altitude species such as water pipit (Anthus spinoletta). It is evident that the alpine species, predicted to undergo serious climatically induced range contractions due to warming climate in the future, already started moving along this trajectory. PMID:26426901

  1. LEARNING TO BE BAD: ADVERSE SOCIAL CONDITIONS, SOCIAL SCHEMAS, AND CRIME

    PubMed Central

    Simons, Ronald L.; Burt, Callie Harbin

    2011-01-01

    In this paper we develop and test a new approach to explain the link between social factors and individual offending. We argue that seemingly disparate family, peer, and community conditions lead to crime because the lessons communicated by these events are similar and promote social schemas involving a hostile view of people and relationships, a preference for immediate rewards, and a cynical view of conventional norms. Further, we posit that these three schemas are interconnected and combine to form a criminogenic knowledge structure that gives rise to situational interpretations legitimating criminal behavior. Structural equation modeling with a sample of roughly 700 hundred African American teens provided strong support for the model. The findings indicated that persistent exposure to adverse conditions such as community crime, discrimination, harsh parenting, deviant peers and low neighborhood collective efficacy increased commitment to the three social schemas. The three schemas were highly intercorrelated and combined to form a latent construct that strongly predicted increases in crime. Further, in large measure the effect of the various adverse conditions on increases in crime was indirect through their impact on this latent construct. We discuss the extent to which the social schematic model presented in the paper might be used to integrate concepts and findings from several of the major theories of criminal behavior. PMID:21760641

  2. Space shuttle orbit maneuvering engine reusable thrust chamber: Adverse operating conditions test report

    NASA Technical Reports Server (NTRS)

    Tobin, R. D.

    1974-01-01

    Test hardware, facilities, and procedures are described along with results of electrically heated tube and channel tests conducted to determine adverse operating condition limits for convectively cooled chambers typical of Space Shuttle Orbit Manuevering Engine designs. Hot-start tests were conducted with corrosion resistant steel and nickel tubes with both monomethylhydrazine and 50-50 coolants. Helium ingestion, in both bubble and froth form, was studied in tubular test sections. Helium bubble ingestion and burn-out limits in rectangular channels were also investigated.

  3. Overland flow connectivity under different climate conditions

    NASA Astrophysics Data System (ADS)

    Hanoch, Lavee

    2015-04-01

    The effect of climate conditions on overland flow connectivity was investigated in arid (mean annual rainfall 120 mm), semi-arid (mean annual rainfall 280 mm) and sub-humid (mean annual rainfall 620 mm) regions. In each of these regions a hillslope reference plot was established, in which soil properties and hydrological variables were measured. The results show that at the regional scale soil organic matter content and aggregate stability decreased with increasing aridity. Infiltration rate also decreased with aridity but overland flow increased. At the hillslope scale, at each of the regions overland flow decreased with increasing hillslope length which means that overland flow is not continuous and water losses increases with hillslope length. In order to understand the controlling factors of overland flow continuity the spatial distribution of soil properties, vegetation cover and overland flow generation mechanisms were measured along hillslopes. The results show that water contributing (source) patches and water collecting (sink) patches exist along the hillslopes, in accordance with the spatial distribution of shrubs. The conclusion is that overland flow connectivity at the hillslope scale is affected mainly by the size, the density and by the spatial distribution of shrubs. An application for preventing soil erosion in urban areas (parks), along roads and in cultivated areas is that planting vegetation in patches or strips is more efficient than all over the hillslopes.

  4. Speech perception under adverse conditions: insights from behavioral, computational, and neuroscience research

    PubMed Central

    Guediche, Sara; Blumstein, Sheila E.; Fiez, Julie A.; Holt, Lori L.

    2014-01-01

    Adult speech perception reflects the long-term regularities of the native language, but it is also flexible such that it accommodates and adapts to adverse listening conditions and short-term deviations from native-language norms. The purpose of this article is to examine how the broader neuroscience literature can inform and advance research efforts in understanding the neural basis of flexibility and adaptive plasticity in speech perception. Specifically, we highlight the potential role of learning algorithms that rely on prediction error signals and discuss specific neural structures that are likely to contribute to such learning. To this end, we review behavioral studies, computational accounts, and neuroimaging findings related to adaptive plasticity in speech perception. Already, a few studies have alluded to a potential role of these mechanisms in adaptive plasticity in speech perception. Furthermore, we consider research topics in neuroscience that offer insight into how perception can be adaptively tuned to short-term deviations while balancing the need to maintain stability in the perception of learned long-term regularities. Consideration of the application and limitations of these algorithms in characterizing flexible speech perception under adverse conditions promises to inform theoretical models of speech. PMID:24427119

  5. Research on long-range laser active imaging system applied in adverse weather conditions

    NASA Astrophysics Data System (ADS)

    Gai, Zhi-gang; Liu, Meng-de; Yang, Li; Kabanov, V. V.; Shi, Lei; Zhao, Jie; Chu, Shi-bo; Yang, Jun-xian; Zhou, Yang

    2013-09-01

    A low-light level night vision device or thermal infrared imager belonging to passive imaging system is generally used in daily target detection and identification. But in adverse weather conditions of dark of night, poor atmospheric transmission characteristics or strong backscattering (fog, dust, rain, snow, etc.), even the most sensitive low-light level night vision could not provide enough image resolution for detecting and identifying targets, and the thermal infrared imager is also limited by low temperature contrast. A long-range laser active imaging system, in combination with high-power semiconductor pulsed lasers with collimation technology, receiving objective lens of large diameter, long focal length and narrow viewing angle, high-gain image intensifier CCD (ICCD) camera and range-gated synchronization control technology, is developed for long distance target detection and high resolution imaging in adverse weather conditions. The system composition and operating principle are introduced. The extremely powerful and efficient illuminators with collimation technology are able to deliver uniform beams, which are essential for illuminating targets at a distance and generating high-quality images. The particular receiving objective lens, ICCD camera and range-gated synchronization control technology could reduce strong backscattering signal and improve imaging signal-to-noise ratio. The laboratory and outfield experiments have been done to validate imaging effect and imaging quality. The results show that the minimum resolution is about 3-5cm, 10cm, and greater than 20 cm for target far from 1100m, 4700m, and 6700m respectively in dark of night. Furthermore, the minimum resolution could reach to 10cm and 20cm for target far from 2500m and 4800m respectively and the image is too blurred to accurately identify the target when observing the target far from 7200m in rainy condition.

  6. A Ground-Based Array to Observe Geospace Electrodynamics During Adverse Space Weather Conditions

    NASA Astrophysics Data System (ADS)

    Sojka, J. J.; Eccles, J. V.; Rice, D.

    2004-05-01

    Geomagnetic Storms occur with surprising frequency and create adverse space weather conditions. During these periods, our knowledge and ability to specify or forecast in adequate detail for user needs is negligible. Neither experimental observations nor theoretical developments have made a significant new impact on the problem for over two decades. Although we can now map Total Electron Content (TEC) in the ionosphere over a continent with sufficient resolution to see coherent long-lived structures, these do not provide constraints on the geospace electrodynamics that is at the heart of our lack of understanding. We present arguments for the need of a continental deployment of ground-based sensors to stepwise advance our understanding of the geospace electrodynamics when it is most adverse from a space weather perspective and also most frustrating from an understanding of Magnetosphere-Ionosphere coupling. That a continental-scale deployment is more productive at addressing the problem than a realizable global distribution is shown. Each measurement is discussed from the point-of-view of either providing new knowledge or becoming a key for future real-time specification and forecasting for user applications. An example of a storm database from one mid-latitude station for the 31 March 2002 is used as a conceptual point in a ground-based array. The presentation focuses on scientific questions that have eluded a quantitative solution for over three decades and view a ground-based array as an "IGY" type of catalyst for answering these questions.

  7. Determination and representation of electric charge distributions associated with adverse weather conditions

    NASA Technical Reports Server (NTRS)

    Rompala, John T.

    1992-01-01

    Algorithms are presented for determining the size and location of electric charges which model storm systems and lightning strikes. The analysis utilizes readings from a grid of ground level field mills and geometric constraints on parameters to arrive at a representative set of charges. This set is used to generate three dimensional graphical depictions of the set as well as contour maps of the ground level electrical environment over the grid. The composite, analytic and graphic package is demonstrated and evaluated using controlled input data and archived data from a storm system. The results demonstrate the packages utility as: an operational tool in appraising adverse weather conditions; a research tool in studies of topics such as storm structure, storm dynamics, and lightning; and a tool in designing and evaluating grid systems.

  8. Functions of Nitric Oxide (NO) in Roots during Development and under Adverse Stress Conditions

    PubMed Central

    Corpas, Francisco J.; Barroso, Juan B.

    2015-01-01

    The free radical molecule, nitric oxide (NO), is present in the principal organs of plants, where it plays an important role in a wide range of physiological functions. Root growth and development are highly regulated by both internal and external factors such as nutrient availability, hormones, pattern formation, cell polarity and cell cycle control. The presence of NO in roots has opened up new areas of research on the role of NO, including root architecture, nutrient acquisition, microorganism interactions and the response mechanisms to adverse environmental conditions, among others. Additionally, the exogenous application of NO throughout the roots has the potential to counteract specific damages caused by certain stresses. This review aims to provide an up-to-date perspective on NO functions in the roots of higher plants. PMID:27135326

  9. Chosen risk level during car-following in adverse weather conditions.

    PubMed

    Hjelkrem, Odd André; Ryeng, Eirin Olaussen

    2016-10-01

    This study examines how precipitation, light conditions and surface conditions affect the drivers' risk perception. An indicator CRI (Chosen Risk Index) is defined, which describes the chosen risk level for drivers in a car-following situation. The dataset contains about 70 000 observations of driver behaviour and weather status on a rural road. Based on the theory of risk homeostasis and an assumption that driving behaviour in situations with daylight, dry road and no precipitation reflects drivers' target level of risk, generalised linear models (GLM) were estimated for cars and trucks separately to reveal the effect of adverse weather conditions on risk perception. The analyses show that both car and truck drivers perceive the highest risk when driving on snow covered roads. For car drivers, a snow covered road in combination with moderate rain or light snow are the factors which lowers the CRI the most. For trucks, snow cover and partially covered roads significantly lowers the CRI, while precipitation did not seem to impose any higher risk. Interaction effects were found for car drivers only. PMID:27454867

  10. Effects of city expansion on heat stress under climate change conditions.

    PubMed

    Argüeso, Daniel; Evans, Jason P; Pitman, Andrew J; Di Luca, Alejandro

    2015-01-01

    We examine the joint contribution of urban expansion and climate change on heat stress over the Sydney region. A Regional Climate Model was used to downscale present (1990-2009) and future (2040-2059) simulations from a Global Climate Model. The effects of urban surfaces on local temperature and vapor pressure were included. The role of urban expansion in modulating the climate change signal at local scales was investigated using a human heat-stress index combining temperature and vapor pressure. Urban expansion and climate change leads to increased risk of heat-stress conditions in the Sydney region, with substantially more frequent adverse conditions in urban areas. Impacts are particularly obvious in extreme values; daytime heat-stress impacts are more noticeable in the higher percentiles than in the mean values and the impact at night is more obvious in the lower percentiles than in the mean. Urban expansion enhances heat-stress increases due to climate change at night, but partly compensates its effects during the day. These differences are due to a stronger contribution from vapor pressure deficit during the day and from temperature increases during the night induced by urban surfaces. Our results highlight the inappropriateness of assessing human comfort determined using temperature changes alone and point to the likelihood that impacts of climate change assessed using models that lack urban surfaces probably underestimate future changes in terms of human comfort. PMID:25668390

  11. Effects of City Expansion on Heat Stress under Climate Change Conditions

    PubMed Central

    Argüeso, Daniel; Evans, Jason P.; Pitman, Andrew J.; Di Luca, Alejandro

    2015-01-01

    We examine the joint contribution of urban expansion and climate change on heat stress over the Sydney region. A Regional Climate Model was used to downscale present (1990–2009) and future (2040–2059) simulations from a Global Climate Model. The effects of urban surfaces on local temperature and vapor pressure were included. The role of urban expansion in modulating the climate change signal at local scales was investigated using a human heat-stress index combining temperature and vapor pressure. Urban expansion and climate change leads to increased risk of heat-stress conditions in the Sydney region, with substantially more frequent adverse conditions in urban areas. Impacts are particularly obvious in extreme values; daytime heat-stress impacts are more noticeable in the higher percentiles than in the mean values and the impact at night is more obvious in the lower percentiles than in the mean. Urban expansion enhances heat-stress increases due to climate change at night, but partly compensates its effects during the day. These differences are due to a stronger contribution from vapor pressure deficit during the day and from temperature increases during the night induced by urban surfaces. Our results highlight the inappropriateness of assessing human comfort determined using temperature changes alone and point to the likelihood that impacts of climate change assessed using models that lack urban surfaces probably underestimate future changes in terms of human comfort. PMID:25668390

  12. Overcoming adverse weather conditions with a common optical path, multiple sensors, and intelligent image fusion system

    NASA Astrophysics Data System (ADS)

    Ng, Joseph; Piacentino, Michael; Caldwell, Brian

    2008-04-01

    Mission success is highly dependent on the ability to accomplish Surveillance, Situation Awareness, Target Detection and Classification, but is challenging under adverse weather conditions. This paper introduces an engineering prototype to address the image collection challenges using a Common Optical Path, Multiple Sensors and an Intelligent Image Fusion System, and provides illustrations and sample fusion images. Panavision's advanced wide spectrum optical design has permitted a suite of imagers to perform observations through a common optical path with a common field of view, thereby aligning images and facilitating optimized downstream image processing. The adaptable design also supports continuous zoom or Galilean lenses for multiple field of views. The Multiple Sensors include: (1) High-definition imaging sensors that are small, have low power consumption and a wide dynamic range; (2) EMCCD sensors that transition from daylight to starlight, even under poor weather conditions, with sensitivity down to 0.00025 Lux; and (3) SWIR sensors that, with the advancement in InGaAs, are able to generate ultra-high sensitivity images from 1-1.7μm reflective light and can achieve imaging through haze and some types of camouflage. The intelligent fusion of multiple sensors provides high-resolution color information with previously impossible sensitivity and contrast. With the integration of Field-Programmable Gate Arrays (FPGAs) and Application-Specific Integrated Circuits (ASICs), real-time Image Processing and Fusion Algorithms can facilitate mission success in a small, low power package.

  13. Energy Partition From Various Climate Conditions And Land Use Types

    NASA Astrophysics Data System (ADS)

    Cheng, Chi-Han; Hsu2, Pang-Chi

    2015-04-01

    Investigating how energy partitions and what factors control energy exchange is critical for better understanding the hydrological cycle, boundary layer dynamics, and land -atmosphere coupling. Climate and land use conditions are the two main factors to control energy partitation. However, previous studies discussed energy partition and factors that controlled Bowen ratio (i.e., ratio of sensible heat flux to latent heat flux) in limited land use types and climate conditions. To provide a more comprehensive analysis over various climate and vegetation types, in this study, we studied eleven different land use types in the eight different climate zones within the United State. The results found out that the Mediterranean climate zone with dry summer season, dry arid (desert) climate zone, and the higher latitude area with severe winter would had higher Bowen ratio, lower precipitation and net radiation. In contrast, the humid climate zones had the lower Bowen ratio, higher net radiation and precipitation. Moreover, the higher Bowen ratio usually happened in the winter or early spring seasons. Regarding land conditions, it is found that soil moistures are the key factor to control Bowen ratio in the drier climate areas. Hence, the grassland and closed shrublands sites have higher Bowen ratio than deciduous broadleaf forests and evergreen needle-leaf forests sites' because of shallower root systems that lack access to the full storage of water in the vadose zone. However, in the humid areas, land use factors, such as stomatal resistance and leaf area, would play an important role in changing latent heat and sensible heat. Based on the tight relationships between Bowen ratio and conditions of climate and land use, we suggest that Bowen ratio could be a useful tool for understanding the potential feedbacks of changes in climate and land use to energy partition and exchange.

  14. Climate change and adverse health events: community perceptions from the Tanahu district of Nepal

    NASA Astrophysics Data System (ADS)

    Mishra, Shiva Raj; Mani Bhandari, Parash; Issa, Rita; Neupane, Dinesh; Gurung, Swadesh; Khanal, Vishnu

    2015-03-01

    Nepal is a country economically dependent on climate-sensitive industries. It is highly vulnerable to the environmental, social, economic and health impacts of climate change. The objective of this study is to explore community perceptions of climate variability and human health risks. In this letter, we present a cross sectional study conducted between August 2013 and July 2014 in the Tanahu district of Nepal. Our analysis is based on 258 face-to-face interviews with household heads utilizing structured questionnaires. Over half of the respondents (54.7%) had perceived a change in climate, 53.9% had perceived an increase in temperature in the summer and 49.2% had perceived an increase in rainfall during the rainy season. Half of the respondents perceived an increase in the number of diseases during the summer, 46.5% perceived an increase during the rainy season and 48.8% during winter. Only 8.9% of the respondents felt that the government was doing enough to prevent climate change and its impact on their community. Belonging to the Janajati (indigenous) ethnic group, living in a pakki, super-pakki house and belonging to poor or mid-level income were related to higher odds of perceiving climate variability. Illiterates were less likely to perceive climate variability. Respondents living in a pakki house, super-pakki, or those who were poor were more likely to perceive health risks. Illiterates were less likely to perceive health risks.

  15. Future Risks of Pest Species under Changing Climatic Conditions.

    PubMed

    Biber-Freudenberger, Lisa; Ziemacki, Jasmin; Tonnang, Henri E Z; Borgemeister, Christian

    2016-01-01

    Most agricultural pests are poikilothermic species expected to respond to climate change. Currently, they are a tremendous burden because of the high losses they inflict on crops and livestock. Smallholder farmers in developing countries of Africa are likely to suffer more under these changes than farmers in the developed world because more severe climatic changes are projected in these areas. African countries further have a lower ability to cope with impacts of climate change through the lack of suitable adapted management strategies and financial constraints. In this study we are predicting current and future habitat suitability under changing climatic conditions for Tuta absoluta, Ceratitis cosyra, and Bactrocera invadens, three important insect pests that are common across some parts of Africa and responsible for immense agricultural losses. We use presence records from different sources and bioclimatic variables to predict their habitat suitability using the maximum entropy modelling approach. We find that habitat suitability for B. invadens, C. cosyra and T. absoluta is partially increasing across the continent, especially in those areas already overlapping with or close to most suitable sites under current climate conditions. Assuming a habitat suitability at three different threshold levels we assessed where each species is likely to be present under future climatic conditions and if this is likely to have an impact on productive agricultural areas. Our results can be used by African policy makers, extensionists and farmers for agricultural adaptation measures to cope with the impacts of climate change. PMID:27054718

  16. Future Risks of Pest Species under Changing Climatic Conditions

    PubMed Central

    Biber-Freudenberger, Lisa; Ziemacki, Jasmin; Tonnang, Henri E. Z.; Borgemeister, Christian

    2016-01-01

    Most agricultural pests are poikilothermic species expected to respond to climate change. Currently, they are a tremendous burden because of the high losses they inflict on crops and livestock. Smallholder farmers in developing countries of Africa are likely to suffer more under these changes than farmers in the developed world because more severe climatic changes are projected in these areas. African countries further have a lower ability to cope with impacts of climate change through the lack of suitable adapted management strategies and financial constraints. In this study we are predicting current and future habitat suitability under changing climatic conditions for Tuta absoluta, Ceratitis cosyra, and Bactrocera invadens, three important insect pests that are common across some parts of Africa and responsible for immense agricultural losses. We use presence records from different sources and bioclimatic variables to predict their habitat suitability using the maximum entropy modelling approach. We find that habitat suitability for B. invadens, C. cosyra and T. absoluta is partially increasing across the continent, especially in those areas already overlapping with or close to most suitable sites under current climate conditions. Assuming a habitat suitability at three different threshold levels we assessed where each species is likely to be present under future climatic conditions and if this is likely to have an impact on productive agricultural areas. Our results can be used by African policy makers, extensionists and farmers for agricultural adaptation measures to cope with the impacts of climate change. PMID:27054718

  17. Simulating Freshwater Availability under Future Climate Conditions

    NASA Astrophysics Data System (ADS)

    Zhao, F.; Zeng, N.; Motesharrei, S.; Gustafson, K. C.; Rivas, J.; Miralles-Wilhelm, F.; Kalnay, E.

    2013-12-01

    Freshwater availability is a key factor for regional development. Precipitation, evaporation, river inflow and outflow are the major terms in the estimate of regional water supply. In this study, we aim to obtain a realistic estimate for these variables from 1901 to 2100. First we calculated the ensemble mean precipitation using the 2011-2100 RCP4.5 output (re-sampled to half-degree spatial resolution) from 16 General Circulation Models (GCMs) participating the Coupled Model Intercomparison Project Phase 5 (CMIP5). The projections are then combined with the half-degree 1901-2010 Climate Research Unit (CRU) TS3.2 dataset after bias correction. We then used the combined data to drive our UMD Earth System Model (ESM), in order to generate evaporation and runoff. We also developed a River-Routing Scheme based on the idea of Taikan Oki, as part of the ESM. It is capable of calculating river inflow and outflow for any region, driven by the gridded runoff output. River direction and slope information from Global Dominant River Tracing (DRT) dataset are included in our scheme. The effects of reservoirs/dams are parameterized based on a few simple factors such as soil moisture, population density and geographic regions. Simulated river flow is validated with river gauge measurements for the world's major rivers. We have applied our river flow calculation to two data-rich watersheds in the United States: Phoenix AMA watershed and the Potomac River Basin. The results are used in our SImple WAter model (SIWA) to explore water management options.

  18. Innovative Air Conditioning and Climate Control

    NASA Technical Reports Server (NTRS)

    Graf, John

    2015-01-01

    NASA needed to develop a desiccant wheel based humidity removal system to enable the long term testing of the Orion CO2 scrubber on the International Space Station. In the course of developing that system, we learned three things that are relevant to energy efficient air conditioning of office towers. NASA developed a conceptual design for a humidity removal system for an office tower environment. We are looking for interested partners to prototype and field test this concept.

  19. Vertical gradient of climate change and climate tourism conditions in the Black Forest.

    PubMed

    Endler, Christina; Oehler, Karoline; Matzarakis, Andreas

    2010-01-01

    Due to the public discussion about global and regional warming, the regional climate and the modified climate conditions are analyzed exemplarily for three different regions in the southern Black Forest (southwest Germany). The driving question behind the present study was how can tourism adapt to modified climate conditions and associated changes to the tourism potential in low mountain ranges. The tourism potential is predominately based on the attractiveness of natural resources being climate-sensitive. In this study, regional climate simulations (A1B) are analyzed by using the REMO model. To analyze the climatic tourism potential, the following thermal, physical and aesthetic parameters are considered for the time span 1961-2050: thermal comfort, heat and cold stress, sunshine, humid-warm conditions (sultriness), fog, precipitation, storm, and ski potential (snow cover). Frequency classes of these parameters expressed as a percentage are processed on a monthly scale. The results are presented in form of the Climate-Tourism-Information-Scheme (CTIS). Due to warmer temperatures, winters might shorten while summers might lengthen. The lowland might be more affected by heat and sultriness (e.g., Freiburg due to the effects of urban climate). To adapt to a changing climate and tourism, the awareness of both stakeholders and tourists as well as the adaptive capability are essential. PMID:19705164

  20. Vertical gradient of climate change and climate tourism conditions in the Black Forest

    NASA Astrophysics Data System (ADS)

    Endler, Christina; Oehler, Karoline; Matzarakis, Andreas

    2010-01-01

    Due to the public discussion about global and regional warming, the regional climate and the modified climate conditions are analyzed exemplarily for three different regions in the southern Black Forest (southwest Germany). The driving question behind the present study was how can tourism adapt to modified climate conditions and associated changes to the tourism potential in low mountain ranges. The tourism potential is predominately based on the attractiveness of natural resources being climate-sensitive. In this study, regional climate simulations (A1B) are analyzed by using the REMO model. To analyze the climatic tourism potential, the following thermal, physical and aesthetic parameters are considered for the time span 1961-2050: thermal comfort, heat and cold stress, sunshine, humid-warm conditions (sultriness), fog, precipitation, storm, and ski potential (snow cover). Frequency classes of these parameters expressed as a percentage are processed on a monthly scale. The results are presented in form of the Climate-Tourism-Information-Scheme (CTIS). Due to warmer temperatures, winters might shorten while summers might lengthen. The lowland might be more affected by heat and sultriness (e.g., Freiburg due to the effects of urban climate). To adapt to a changing climate and tourism, the awareness of both stakeholders and tourists as well as the adaptive capability are essential.

  1. Pathways from childhood abuse and other adversities to adult health risks: The role of adult socioeconomic conditions.

    PubMed

    Font, Sarah A; Maguire-Jack, Kathryn

    2016-01-01

    Adverse childhood experiences (ACEs), including child abuse, have been linked with poor health outcomes in adulthood. The mechanisms that explain these relations are less understood. This study assesses whether associations of ACEs and health risks are mediated by adult socioeconomic conditions, and whether these pathways are different for maltreatment than for other types of adversities. Using the Behavioral Risk Factor Surveillance System 2012 survey (N=29,229), we employ structural equation modeling to (1) estimate associations of the number and type of ACEs with five health risks-depression, obesity, tobacco use, binge drinking, and self-reported sub-optimal health; and (2) assess whether adult socioeconomic conditions-marriage, divorce and separation, educational attainment, income and insurance status-mediate those associations. Findings suggest both direct and indirect associations between ACEs and health risks. At high numbers of ACEs, 15-20% of the association between number of ACEs and adult health risks was attributable to socioeconomic conditions. Associations of three ACEs (exposure to domestic violence, parental divorce, and residing with a person who was incarcerated) with health risks were nearly entirely explained by socioeconomic conditions in adulthood. However, child physical, emotional, and sexual abuse were significantly associated with several adult health risks, beyond the effects of other adversities, and socioeconomic conditions explained only a small portion of these associations. These findings suggest that the pathways to poor adult health differ by types of ACEs, and that childhood abuse is more likely than other adversities to have a direct impact. PMID:26059537

  2. Changes in alpine plant growth under future climate conditions

    NASA Astrophysics Data System (ADS)

    Rammig, A.; Jonas, T.; Zimmermann, N. E.; Rixen, C.

    2010-06-01

    Alpine shrub- and grasslands are shaped by extreme climatic conditions such as a long-lasting snow cover and a short vegetation period. Such ecosystems are expected to be highly sensitive to global environmental change. Prolonged growing seasons and shifts in temperature and precipitation are likely to affect plant phenology and growth. In a unique experiment, climatology and plant growth was monitored for almost a decade at 17 snow meteorological stations in different alpine regions along the Swiss Alps. Regression analyses revealed highly significant correlations between mean air temperature in May/June and snow melt out, onset of plant growth, and plant height. These correlations were used to project plant growth phenology for future climate conditions based on the gridded output of a set of regional climate models runs. Melt out and onset of growth were projected to occur on average 17 days earlier by the end of the century than in the control period from 1971-2000 under the future climate conditions of the low resolution climate model ensemble. Plant height and biomass production were expected to increase by 77% and 45%, respectively. The earlier melt out and onset of growth will probably cause a considerable shift towards higher growing plants and thus increased biomass. Our results represent the first quantitative and spatially explicit estimates of climate change impacts on future growing season length and the respective productivity of alpine plant communities in the Swiss Alps.

  3. Changes in alpine plant growth under future climate conditions

    NASA Astrophysics Data System (ADS)

    Rammig, A.; Jonas, T.; Zimmermann, N. E.; Rixen, C.

    2009-11-01

    Alpine shrub- and grasslands are shaped by extreme climatic conditions such as a long-lasting snow cover and a short vegetation period. Such ecosystems are expected to be highly sensitive to global environmental change. Prolonged growing seasons and shifts in temperature and precipitation are likely to affect plant phenology and growth. In a unique experiment, climatology and plant growth was monitored for almost a decade at 17 snow meteorological stations in different alpine regions along the Swiss Alps. Regression analyses revealed highly significant correlations between mean air temperature in May/June and snow melt-out, onset of plant growth, and plant height. These correlations were used to project plant growth phenology for future climate conditions based on the gridded output of a set of regional climate models runs. Melt-out and onset of growth were projected to occur on average 17 days earlier by the end of the century than in the control period from 1971-2000 under the future climate conditions of the low resolution climate model ensemble. Plant height and biomass production were expected to increase by 77% and 45%, respectively. The earlier melt-out and onset of growth will probably cause a considerable shift towards higher growing plants and thus increased biomass. Our results represent the first quantitative and spatially explicit estimates of climate change impacts on future growing season length and the respective productivity of alpine plant communities in the Swiss Alps.

  4. 24 CFR 3285.404 - Severe climatic conditions.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ....404 Severe climatic conditions. In frost-susceptible soil locations, ground anchor augers must be installed below the frost line, unless the foundation system is frost-protected to prevent the effects of frost heave, in accordance with acceptable engineering practice and § 3280.306 of this chapter...

  5. 24 CFR 3285.404 - Severe climatic conditions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ....404 Severe climatic conditions. In frost-susceptible soil locations, ground anchor augers must be installed below the frost line, unless the foundation system is frost-protected to prevent the effects of frost heave, in accordance with acceptable engineering practice and § 3280.306 of this chapter...

  6. 24 CFR 3285.404 - Severe climatic conditions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ....404 Severe climatic conditions. In frost-susceptible soil locations, ground anchor augers must be installed below the frost line, unless the foundation system is frost-protected to prevent the effects of frost heave, in accordance with acceptable engineering practice and § 3280.306 of this chapter...

  7. 24 CFR 3285.404 - Severe climatic conditions.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ....404 Severe climatic conditions. In frost-susceptible soil locations, ground anchor augers must be installed below the frost line, unless the foundation system is frost-protected to prevent the effects of frost heave, in accordance with acceptable engineering practice and § 3280.306 of this chapter...

  8. 24 CFR 3285.404 - Severe climatic conditions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ....404 Severe climatic conditions. In frost-susceptible soil locations, ground anchor augers must be installed below the frost line, unless the foundation system is frost-protected to prevent the effects of frost heave, in accordance with acceptable engineering practice and § 3280.306 of this chapter...

  9. Predicting Weather Conditions and Climate for Mars Expeditions

    NASA Astrophysics Data System (ADS)

    Read, P. L.; Lewis, S. R.; Bingham, S. J.; Newman, C. E.

    Weather and climatic conditions are among the most important factors to be taken into account when planning expeditions to remote and challenging locations on Earth. This is likely to be equally the case for expedition planners on Mars, where conditions (in terms of extremes of temperature, etc.) can be at least as daunting as back on Earth. With the success of recent unmanned missions to Mars, such as NASA's Mars Pathfinder, Mars Global Surveyor and Mars Odyssey, there is now a great deal of information available on the range of environ- mental conditions on Mars, from the tropics to the CO2 ice-covered polar caps. This has been further supple- mented by the development of advanced numerical models of the Martian atmosphere, allowing detailed and accurate simulations and predictions of the weather and climate across the planet. This report discusses the main weather and climate variables which future Martian human expedition planners will need to take into account. The range of conditions likely to be encountered at a variety of typical locations on Mars is then considered, with reference to predictions from the ESA Mars Climate Database.

  10. Forecasting conditional climate-change using a hybrid approach

    USGS Publications Warehouse

    Esfahani, Akbar Akbari; Friedel, Michael J.

    2014-01-01

    A novel approach is proposed to forecast the likelihood of climate-change across spatial landscape gradients. This hybrid approach involves reconstructing past precipitation and temperature using the self-organizing map technique; determining quantile trends in the climate-change variables by quantile regression modeling; and computing conditional forecasts of climate-change variables based on self-similarity in quantile trends using the fractionally differenced auto-regressive integrated moving average technique. The proposed modeling approach is applied to states (Arizona, California, Colorado, Nevada, New Mexico, and Utah) in the southwestern U.S., where conditional forecasts of climate-change variables are evaluated against recent (2012) observations, evaluated at a future time period (2030), and evaluated as future trends (2009–2059). These results have broad economic, political, and social implications because they quantify uncertainty in climate-change forecasts affecting various sectors of society. Another benefit of the proposed hybrid approach is that it can be extended to any spatiotemporal scale providing self-similarity exists.

  11. Comparing Observed Hurricane Conditions Against Potential Future Climate Change Influences

    NASA Astrophysics Data System (ADS)

    Graham, W. D.

    2012-12-01

    Climate Adaptation Science Investigators: (CASI) is to advance and apply NASA's scientific expertise and products to develop climate adaptation strategies that support NASA's overall mission by minimizing risks to each center's operations, physical assets, and personnel. Using Hurricane Katrina observations as a baseline, we use ADCIRC to model surge extent with simple modifications of the storm track. We examine two time now (T0) scenarios of present-day climatological factors: 1) translating the 2005 path 7 km west; and 2) rotating the approach angle from due-north to WNW. Second, we examine two future time scenarios (TX) by infusing climate change conditions, such as sea level rise and increased storm intensity, into a T0 baseline to assess future impacts. The primary goal of this work entails planning and protecting NASA assets and infrastructure. The adjacent communities, state and local emergency managers, gain benefit from this NASA work as data and analysis includes the surrounding geography.

  12. Geoeffective and Climate-Influencing Solar and Interplanetary Conditions

    NASA Astrophysics Data System (ADS)

    Baranyi, T.; Ludmány, A.

    Several connections have been detected and demonstrated between solar magnetic conditions and climatic responses which hint at a highly complicated mechanism of sun-climate relations through plasma streams. The present contribution overviews our results about the possible factors of this mechanism. The main factor is the negative value of the interplanetary magnetic B_z component which exhibits a fairly complex behaviour. Its strength is influenced by the solar dipole cycle, the nature of ejected plasma (CME or fast stream), the magnetic topology of the CME and the position of the Earth (Rosenberg-Coleman and Russell-McPherron effects). The persistence of the negative B_z is also effective. The impacts of these features can be pointed out in the climatic responses.

  13. [WORKING CONDITIONS AND THE HEALTH STATE OF FEMALE WORKERS IN DAIRY ENTERPRISES IN VARIOUS CLIMATIC CONDITIONS].

    PubMed

    Rakitina, I S; Lyapkalo, A A; Chudinin, N V

    2016-01-01

    The paper presents a comprehensive sanitary - hygienic assessment of working conditions for female workers in dairy enterprises located in different climatic regions. On the basis of this assessment, a set of preventive measures aimed at improvement of the working conditions and the health state offemale workers may be developed and implemented. PMID:27430066

  14. 30 CFR 285.816 - What must I do if environmental or other conditions adversely affect a cable, pipeline, or facility?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What must I do if environmental or other conditions adversely affect a cable, pipeline, or facility? 285.816 Section 285.816 Mineral Resources..., pipeline, or facility? If environmental or other conditions adversely affect a cable, pipeline, or...

  15. Ceramic production during changing environmental/climatic conditions

    NASA Astrophysics Data System (ADS)

    Oestreich, Daniela B.; Glasmacher, Ulrich A.

    2015-04-01

    Ceramics, with regard to their status as largely everlasting everyday object as well as on the basis of their chronological sensitivity, reflect despite their simplicity the technological level of a culture and therefore also, directly or indirectly, the adaptability of a culture with respect to environmental and/or climatic changes. For that reason the question arises, if it is possible to identify changes in production techniques and raw material sources for ceramic production, as a response to environmental change, e.g. climate change. This paper will present results of a research about Paracas Culture (800 - 200 BC), southern Peru. Through several investigations (e.g. Schittek et al., 2014; Eitel and Mächtle, 2009) it is well known that during Paracas period changes in climate and environmental conditions take place. As a consequence, settlement patterns shifted several times through the various stages of Paracas time. Ceramics from three different sites (Jauranga, Cutamalla, Collanco) and temporal phases of the Paracas period are detailed archaeometric, geochemical and mineralogical characterized, e.g. Raman spectroscopy, XRD, and ICP-MS analyses. The aim of this research is to resolve potential differences in the chemical composition of the Paracas ceramics in space and time and to compare the data with the data sets of pre-Columbian environmental conditions. Thus influences of changing environmental conditions on human societies and their cultural conditions will be discussed. References Eitel, B. and Mächtle, B. 2009. Man and Environment in the eastern Atacama Desert (Southern Peru): Holocene climate changes and their impact on pre-Columbian cultures. In: Reindel, M. & Wagner, G. A. (eds.) New Technologies for Archaeology. Berlin Heidelberg: Springer-Verlag. Schittek, K., Mächtle, B., Schäbitz, F., Forbriger, M., Wennrich, V., Reindel, M., and Eitel, B.. Holocene environmental changes in the highlands of the southern Peruvian Andes (14° S) and their

  16. Global flood risks under changing climate and socioeconomic conditions

    NASA Astrophysics Data System (ADS)

    Sperna Weiland, Frederiek; Ward, Philip; Bouwman, Arno; Ligtvoet, Willem; van Beek, Rens; Winsemius, Hessel

    2013-04-01

    Worldwide major flood events result in both economic losses and large numbers of casualties. Recent global scale studies indicate that in many regions of the world discharge extremes are likely to increase under changing climate conditions. However, few studies have so far examined how these changes in climate conditions may affect flood risk (defined here as the probability of a flood multiplied by the consequences). In the current study we investigate the impacts of changing climate and socioeconomic conditions on flood extents and depths, and also assess the potential impacts on flood risk. The study is conducted on a global scale, thereby indicating in which regions of the world flood risk is likely to change most. To assess global food risk under changing conditions, we combined socio-economic data from the Integrated Model to Assess the Global Environment (IMAGE) framework of the Netherlands Environmental Assessment Agency (PBL) with high resolution maps of inundation depth (1 km). To this end, projections from a number of GCMs were bias-corrected and used to force the global hydrological model PCR-GLOBWB which simulates (amongst other variables) global maps with daily flood volumes on a 0.5 degree resolution. These time series were used to derive flood volume maps for multiple return periods, which were downscaled to inundation depth maps at 1 km resolution using a 1 km resolution DEM. Finally, these high resolution flood maps were combined with spatial datasets on future GDP and population density from the IMAGE model. Results are presented on both the global scale and at the country level. We believe that the obtained flood extend and flood risk maps can assist development agencies in planning climate adaptation investments that aim to reduce flood risks.

  17. Variable climatic conditions dominate recent phytoplankton dynamics in Chesapeake Bay

    PubMed Central

    Harding, Jr., Lawrence W.; Mallonee, Michael E.; Perry, Elgin S.; Miller, W. David; Adolf, Jason E.; Gallegos, Charles L.; Paerl, Hans W.

    2016-01-01

    Variable climatic conditions strongly influence phytoplankton dynamics in estuaries globally. Our study area is Chesapeake Bay, a highly productive ecosystem providing natural resources, transportation, and recreation for nearly 16 million people inhabiting a 165,000-km2 watershed. Since World War II, nutrient over-enrichment has led to multiple ecosystem impairments caused by increased phytoplankton biomass as chlorophyll-a (chl-a). Doubled nitrogen (N) loadings from 1945–1980 led to increased chl-a, reduced water clarity, and low dissolved oxygen (DO), while decreased N loadings from 1981–2012 suggest modest improvement. The recent 30+ years are characterized by high inter-annual variability of chl-a, coinciding with irregular dry and wet periods, complicating the detection of long-term trends. Here, we synthesize time-series data for historical and recent N loadings (TN, NO2 + NO3), chl-a, floral composition, and net primary productivity (NPP) to distinguish secular changes caused by nutrient over-enrichment from spatio-temporal variability imposed by climatic conditions. Wet years showed higher chl-a, higher diatom abundance, and increased NPP, while dry years showed lower chl-a, lower diatom abundance, and decreased NPP. Our findings support a conceptual model wherein variable climatic conditions dominate recent phytoplankton dynamics against a backdrop of nutrient over-enrichment, emphasizing the need to separate these effects to gauge progress toward improving water quality in estuaries. PMID:27026279

  18. Variable climatic conditions dominate recent phytoplankton dynamics in Chesapeake Bay.

    PubMed

    Harding, Lawrence W; Mallonee, Michael E; Perry, Elgin S; Miller, W David; Adolf, Jason E; Gallegos, Charles L; Paerl, Hans W

    2016-01-01

    Variable climatic conditions strongly influence phytoplankton dynamics in estuaries globally. Our study area is Chesapeake Bay, a highly productive ecosystem providing natural resources, transportation, and recreation for nearly 16 million people inhabiting a 165,000-km(2) watershed. Since World War II, nutrient over-enrichment has led to multiple ecosystem impairments caused by increased phytoplankton biomass as chlorophyll-a (chl-a). Doubled nitrogen (N) loadings from 1945-1980 led to increased chl-a, reduced water clarity, and low dissolved oxygen (DO), while decreased N loadings from 1981-2012 suggest modest improvement. The recent 30+ years are characterized by high inter-annual variability of chl-a, coinciding with irregular dry and wet periods, complicating the detection of long-term trends. Here, we synthesize time-series data for historical and recent N loadings (TN, NO2 + NO3), chl-a, floral composition, and net primary productivity (NPP) to distinguish secular changes caused by nutrient over-enrichment from spatio-temporal variability imposed by climatic conditions. Wet years showed higher chl-a, higher diatom abundance, and increased NPP, while dry years showed lower chl-a, lower diatom abundance, and decreased NPP. Our findings support a conceptual model wherein variable climatic conditions dominate recent phytoplankton dynamics against a backdrop of nutrient over-enrichment, emphasizing the need to separate these effects to gauge progress toward improving water quality in estuaries. PMID:27026279

  19. Variable climatic conditions dominate recent phytoplankton dynamics in Chesapeake Bay

    NASA Astrophysics Data System (ADS)

    Harding, Lawrence W., Jr.; Mallonee, Michael E.; Perry, Elgin S.; Miller, W. David; Adolf, Jason E.; Gallegos, Charles L.; Paerl, Hans W.

    2016-03-01

    Variable climatic conditions strongly influence phytoplankton dynamics in estuaries globally. Our study area is Chesapeake Bay, a highly productive ecosystem providing natural resources, transportation, and recreation for nearly 16 million people inhabiting a 165,000-km2 watershed. Since World War II, nutrient over-enrichment has led to multiple ecosystem impairments caused by increased phytoplankton biomass as chlorophyll-a (chl-a). Doubled nitrogen (N) loadings from 1945–1980 led to increased chl-a, reduced water clarity, and low dissolved oxygen (DO), while decreased N loadings from 1981–2012 suggest modest improvement. The recent 30+ years are characterized by high inter-annual variability of chl-a, coinciding with irregular dry and wet periods, complicating the detection of long-term trends. Here, we synthesize time-series data for historical and recent N loadings (TN, NO2 + NO3), chl-a, floral composition, and net primary productivity (NPP) to distinguish secular changes caused by nutrient over-enrichment from spatio-temporal variability imposed by climatic conditions. Wet years showed higher chl-a, higher diatom abundance, and increased NPP, while dry years showed lower chl-a, lower diatom abundance, and decreased NPP. Our findings support a conceptual model wherein variable climatic conditions dominate recent phytoplankton dynamics against a backdrop of nutrient over-enrichment, emphasizing the need to separate these effects to gauge progress toward improving water quality in estuaries.

  20. Influence of weather-climatic conditions on biospheric processes

    NASA Astrophysics Data System (ADS)

    Govorushko, S. M.

    2012-12-01

    The significance of meteorological processes and phenomena in the biosphere functioning is revealed. The influence of various weather conditions on human health is considered; the factors and mechanisms of their action are described. The impact of meteorological processes on animals is discussed and concrete examples of such impacts are presented. The influence of meteorological processes and phenomena on plants at different stages of their life (pollination, growth, ripening, transport of seeds, damage, and death) and on some abiotic natural components is shown. It is inferred that weather-climatic conditions have a great influence on biospheric processes.

  1. Ecoclimatic indicators to study crop suitability in present and future climatic conditionsTIC CONDITIONS

    NASA Astrophysics Data System (ADS)

    Caubel, Julie; Garcia de Cortazar Atauri, Inaki; Huard, Frédéric; Launay, Marie; Ripoche, Dominique; Gouache, David; Bancal, Marie-Odile; Graux, Anne-Isabelle; De Noblet, Nathalie

    2013-04-01

    Climate change is expected to affect both regional and global food production through changes in overall agroclimatic conditions. It is therefore necessary to develop simple tools of crop suitability diagnosis in a given area so that stakeholders can envisage land use adaptations under climate change conditions. The most common way to investigate potential impacts of climate on the evolution of agrosystems is to make use of an array of agroclimatic indicators, which provide synthetic information derived from climatic variables and calculated within fixed periods (i.e. January first - 31th July). However, the information obtained during these periods does not enable to take account of the plant response to climate. In this work, we present some results of the research program ORACLE (Opportunities and Risks of Agrosystems & forests in response to CLimate, socio-economic and policy changEs in France (and Europe). We proposed a suite of relevant ecoclimatic indicators, based on temperature and rainfall, in order to evaluate crop suitability for both present and new climatic conditions. Ecoclimatic indicators are agroclimatic indicators (e.g., grain heat stress) calculated during specific phenological phases so as to take account of the plant response to climate (e.g., the grain filling period, flowering- harvest). These indicators are linked with the ecophysiological processes they characterize (for e.g., the grain filling). To represent this methodology, we studied the suitability of winter wheat in future climatic conditions through three distinct French sites, Toulouse, Dijon and Versailles. Indicators have been calculated using climatic data from 1950 to 2100 simulated by the global climate model ARPEGE forced by a greenhouse effect corresponding to the SRES A1B scenario. The Quantile-Quantile downscaling method was applied to obtain data for the three locations. Phenological stages (emergence, ear 1 cm, flowering, beginning of grain filling and harvest) have been

  2. Agricultural pests under future climate conditions: downscaling of regional climate scenarios with a stochastic weather generator

    NASA Astrophysics Data System (ADS)

    Hirschi, M.; Stöckli, S.; Dubrovsky, M.; Spirig, C.; Rotach, M. W.; Calanca, P.; Samietz, J.

    2010-09-01

    As a consequence of current and projected climate change in temperate regions of Europe, agricultural pests and diseases are expected to occur more frequently and possibly to extend to previously unaffected regions. Given their economic and ecological relevance, detailed forecasting tools for various pests have been developed, which model the infestation depending on actual weather conditions. Assessing the future risk of pest-related damages therefore requires future weather data at high temporal and spatial resolution. In particular, pest forecast models are often not based on screen temperature and precipitation alone (i.e., the most generally projected climate variables), but might require input variables such as soil temperature, in-canopy net radiation or leaf wetness. Here, we use a stochastic weather and a re-sampling procedure for producing site-specific hourly weather data from regional climate change scenarios for 2050 in Switzerland. The climate change scenarios were derived from multi-model projections and provide probabilistic information on future regional changes in temperature and precipitation. Hourly temperature, precipitation and radiation data were produced by first generating daily weather data for these climate scenarios and then using a nearest neighbor re-sampling approach for creating realistic diurnal cycles. These hourly weather time series were then used for modeling important phases in the lifecycle of codling moth, the major insect pest in apple orchards worldwide. First results indicate a shift in the occurrence and duration of phases relevant for pest disease control for projected as compared to current climate (e.g. the flight of the codling moth starts about ten days earlier in future climate), continuing an already observed trend towards more favorable conditions for this insect during the last 20 years.

  3. Climate Twins - a tool to explore future climate impacts by assessing real world conditions: Exploration principles, underlying data, similarity conditions and uncertainty ranges

    NASA Astrophysics Data System (ADS)

    Loibl, Wolfgang; Peters-Anders, Jan; Züger, Johann

    2010-05-01

    To achieve public awareness and thorough understanding about expected climate changes and their future implications, ways have to be found to communicate model outputs to the public in a scientifically sound and easily understandable way. The newly developed Climate Twins tool tries to fulfil these requirements via an intuitively usable web application, which compares spatial patterns of current climate with future climate patterns, derived from regional climate model results. To get a picture of the implications of future climate in an area of interest, users may click on a certain location within an interactive map with underlying future climate information. A second map depicts the matching Climate Twin areas according to current climate conditions. In this way scientific output can be communicated to the public which allows for experiencing climate change through comparison with well-known real world conditions. To identify climatic coincidence seems to be a simple exercise, but the accuracy and applicability of the similarity identification depends very much on the selection of climate indicators, similarity conditions and uncertainty ranges. Too many indicators representing various climate characteristics and too narrow uncertainty ranges will judge little or no area as regions with similar climate, while too little indicators and too wide uncertainty ranges will address too large regions as those with similar climate which may not be correct. Similarity cannot be just explored by comparing mean values or by calculating correlation coefficients. As climate change triggers an alteration of various indicators, like maxima, minima, variation magnitude, frequency of extreme events etc., the identification of appropriate similarity conditions is a crucial question to be solved. For Climate Twins identification, it is necessary to find a right balance of indicators, similarity conditions and uncertainty ranges, unless the results will be too vague conducting a

  4. Formation of aerobic granular sludge under adverse conditions: low DO and high ammonia.

    PubMed

    Zhang, Sheng-Hua; Zhang, Xiao-Hu; Lv, Lu; Wang, Qing; Jiang, Qipei

    2013-04-01

    In this study, two adverse environments: low dissolved oxygen (DO) and high ammonia concentration, were employed to investigate the morphology, interspecies quorum sensing, extracellular polymers (EPS) characterization and microbial communities in the formation of aerobic granular sludge. Results showed that low DO could promote filamentous bacterial outgrowth. Under high ammonia concentration aerobic granular sludge (AGS) could still be cultivated, although it was looser and lighter than the control group. During the early stage of the AGS cultivation process, Al-2 activity reached a peak value in all three reactors, and ultrasonic pre-treatment was not beneficial to the release of Al-2. During AGS formation, the production of polysaccharide exhibited increases from 12.2% to 40.3%, 49.6%, and 29.3%. And PS in R2 was the highest as the result of sludge bulking. PS/PN was 1.5 to approximately 8 in the three reactors. Three-dimensional EEM fuorescence spectroscopy variation indicated the change of protein in EPS, and the highest intensity of Peak T1 was obtained. The location shift of Peak T1 was not obvious, and Peaks A, C, and T2 shifted toward longer wavelengths (red shift) of 5 to approximately 60 nm, or shorter wavelengths (blue shift) of 10 to approximately 25 nm on the emission scale and/or excitation scale in all three reactors. This provided spectral information on the chemical structure changes. Bacteria in R3 had the highest species diversity, and all bacteria in beta-Proteobacteria were identified as genus Thauera, which suggested that simultaneous nitrification and denitrification occurred in R3. The filamentous bacteria in seed sludge and R2 were species-richer. There was a low abundance of filamentous bacteria in R1 and R3, which contributed to the granule structure stability. PMID:24620612

  5. Adverse foraging conditions may impact body mass and survival of a high Arctic seabird

    USGS Publications Warehouse

    Harding, A.M.A.; Welcker, J.; Steen, H.; Hamer, K.C.; Kitaysky, A.S.; Fort, J.; Talbot, S.L.; Cornick, L.A.; Karnovsky, N.J.; Gabrielsen, G.W.; Gremillet, D.

    2011-01-01

    Tradeoffs between current reproduction and future survival are widely recognized, but may only occur when food is limited: when foraging conditions are favorable, parents may be able to reproduce without compromising their own survival. We investigated these tradeoffs in the little auk (Alle alle), a small seabird with a single-egg clutch. During 2005-2007, we examined the relationship between body mass and survival of birds breeding under contrasting foraging conditions at two Arctic colonies. We used corticosterone levels of breeding adults as a physiological indicator of the foraging conditions they encountered during each reproductive season. We found that when foraging conditions were relatively poor (as reflected in elevated levels of corticosterone), parents ended the reproductive season with low body mass and suffered increased post-breeding mortality. A positive relationship between body mass and post-breeding survival was found in one study year; light birds incurred higher survival costs than heavy birds. The results of this study suggest that reproducing under poor foraging conditions may affect the post-breeding survival of long-lived little auks. They also have important demographic implications because even a small change in adult survival may have a large effect on populations of long-lived species. ?? 2011 Springer-Verlag.

  6. Diverging responses of tropical Andean biomes under future climate conditions.

    PubMed

    Tovar, Carolina; Arnillas, Carlos Alberto; Cuesta, Francisco; Buytaert, Wouter

    2013-01-01

    Observations and projections for mountain regions show a strong tendency towards upslope displacement of their biomes under future climate conditions. Because of their climatic and topographic heterogeneity, a more complex response is expected for biodiversity hotspots such as tropical mountain regions. This study analyzes potential changes in the distribution of biomes in the Tropical Andes and identifies target areas for conservation. Biome distribution models were developed using logistic regressions. These models were then coupled to an ensemble of 8 global climate models to project future distribution of the Andean biomes and their uncertainties. We analysed projected changes in extent and elevational range and identified regions most prone to change. Our results show a heterogeneous response to climate change. Although the wetter biomes exhibit an upslope displacement of both the upper and the lower boundaries as expected, most dry biomes tend to show downslope expansion. Despite important losses being projected for several biomes, projections suggest that between 74.8% and 83.1% of the current total Tropical Andes will remain stable, depending on the emission scenario and time horizon. Between 3.3% and 7.6% of the study area is projected to change, mostly towards an increase in vertical structure. For the remaining area (13.1%-17.4%), there is no agreement between model projections. These results challenge the common believe that climate change will lead to an upslope displacement of biome boundaries in mountain regions. Instead, our models project diverging responses, including downslope expansion and large areas projected to remain stable. Lastly, a significant part of the area expected to change is already affected by land use changes, which has important implications for management. This, and the inclusion of a comprehensive uncertainty analysis, will help to inform conservation strategies in the Tropical Andes, and to guide similar assessments for other

  7. Diverging Responses of Tropical Andean Biomes under Future Climate Conditions

    PubMed Central

    Tovar, Carolina; Arnillas, Carlos Alberto; Cuesta, Francisco; Buytaert, Wouter

    2013-01-01

    Observations and projections for mountain regions show a strong tendency towards upslope displacement of their biomes under future climate conditions. Because of their climatic and topographic heterogeneity, a more complex response is expected for biodiversity hotspots such as tropical mountain regions. This study analyzes potential changes in the distribution of biomes in the Tropical Andes and identifies target areas for conservation. Biome distribution models were developed using logistic regressions. These models were then coupled to an ensemble of 8 global climate models to project future distribution of the Andean biomes and their uncertainties. We analysed projected changes in extent and elevational range and identified regions most prone to change. Our results show a heterogeneous response to climate change. Although the wetter biomes exhibit an upslope displacement of both the upper and the lower boundaries as expected, most dry biomes tend to show downslope expansion. Despite important losses being projected for several biomes, projections suggest that between 74.8% and 83.1% of the current total Tropical Andes will remain stable, depending on the emission scenario and time horizon. Between 3.3% and 7.6% of the study area is projected to change, mostly towards an increase in vertical structure. For the remaining area (13.1%–17.4%), there is no agreement between model projections. These results challenge the common believe that climate change will lead to an upslope displacement of biome boundaries in mountain regions. Instead, our models project diverging responses, including downslope expansion and large areas projected to remain stable. Lastly, a significant part of the area expected to change is already affected by land use changes, which has important implications for management. This, and the inclusion of a comprehensive uncertainty analysis, will help to inform conservation strategies in the Tropical Andes, and to guide similar assessments for

  8. Statistical Modeling of Low Flow Conditions based on Climatic Indicators

    NASA Astrophysics Data System (ADS)

    Fangmann, Anne; Haberlandt, Uwe

    2015-04-01

    Regression-based approaches in climate change impact assessment may pose a practical alternative to the application of process-based hydrological models, especially with respect to low flow extremes. Extended durations and spatial dimensions allow for a quantitative assessment and exploitation of the interrelations between atmospheric driving forces and streamflow response during dry periods, and eventually for the prognosis of future low flow conditions based on climate model input. This study aims at using combinations of climatic indicators, quantifying a variety of meteorological drought characteristics, to model specific low flow indices, based solely on multiple linear regressions. The area under investigation is the federal state of Lower Saxony, Germany. Daily time series of climate and streamflow data pose the basis for calculation of a set of meteorological and hydrological indices, serving as regressors and regressands, respectively. Two approaches are being analyzed: a) a station-based approach, fitting a specific regression equation at each discharge gauge with sufficient record length, and b) a regional approach, enabling the estimation of low flow indices at ungauged sites and stations with minor record length. The station-based procedure is used for estimation of annual low flow index values from annual meteorological conditions. Subsequent fitting of distribution functions to the estimated values allows for the assessment of return periods of the low flow indices. The regionalization, on the other hand, is designed to directly estimate the shapes of the distribution functions by applying L-moment regressions, enabling a direct assessment of specific index values for the return periods in demand.

  9. Contact mechanics of modular metal-on-polyethylene total hip replacement under adverse edge loading conditions.

    PubMed

    Hua, Xijin; Li, Junyan; Wang, Ling; Jin, Zhongmin; Wilcox, Ruth; Fisher, John

    2014-10-17

    Edge loading can negatively impact the biomechanics and long-term performance of hip replacements. Although edge loading has been widely investigated for hard-on-hard articulations, limited work has been conducted for hard-on-soft combinations. The aim of the present study was to investigate edge loading and its effect on the contact mechanics of a modular metal-on-polyethylene (MoP) total hip replacement (THR). A three-dimensional finite element model was developed based on a modular MoP bearing. Different cup inclination angles and head lateral microseparation were modelled and their effect on the contact mechanics of the modular MoP hip replacement were examined. The results showed that lateral microseparation caused loading of the head on the rim of the cup, which produced substantial increases in the maximum von Mises stress in the polyethylene liner and the maximum contact pressure on both the articulating surface and backside surface of the liner. Plastic deformation of the liner was observed under both standard conditions and microseparation conditions, however, the maximum equivalent plastic strain in the liner under microseparation conditions of 2000 µm was predicted to be approximately six times that under standard conditions. The study has indicated that correct positioning the components to avoid edge loading is likely to be important clinically even for hard-on-soft bearings for THR. PMID:25218504

  10. Contact mechanics of modular metal-on-polyethylene total hip replacement under adverse edge loading conditions

    PubMed Central

    Hua, Xijin; Li, Junyan; Wang, Ling; Jin, Zhongmin; Wilcox, Ruth; Fisher, John

    2014-01-01

    Edge loading can negatively impact the biomechanics and long-term performance of hip replacements. Although edge loading has been widely investigated for hard-on-hard articulations, limited work has been conducted for hard-on-soft combinations. The aim of the present study was to investigate edge loading and its effect on the contact mechanics of a modular metal-on-polyethylene (MoP) total hip replacement (THR). A three-dimensional finite element model was developed based on a modular MoP bearing. Different cup inclination angles and head lateral microseparation were modelled and their effect on the contact mechanics of the modular MoP hip replacement were examined. The results showed that lateral microseparation caused loading of the head on the rim of the cup, which produced substantial increases in the maximum von Mises stress in the polyethylene liner and the maximum contact pressure on both the articulating surface and backside surface of the liner. Plastic deformation of the liner was observed under both standard conditions and microseparation conditions, however, the maximum equivalent plastic strain in the liner under microseparation conditions of 2000 µm was predicted to be approximately six times that under standard conditions. The study has indicated that correct positioning the components to avoid edge loading is likely to be important clinically even for hard-on-soft bearings for THR. PMID:25218504

  11. 30 CFR 585.816 - What must I do if environmental or other conditions adversely affect a cable, pipeline, or facility?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What must I do if environmental or other conditions adversely affect a cable, pipeline, or facility? 585.816 Section 585.816 Mineral Resources BUREAU... corrective action to BOEM within 30 days of the discovery of the adverse effect. (b) Take remedial action...

  12. 30 CFR 285.816 - What must I do if environmental or other conditions adversely affect a cable, pipeline, or facility?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What must I do if environmental or other conditions adversely affect a cable, pipeline, or facility? 285.816 Section 285.816 Mineral Resources BUREAU...: (a) Submit a plan of corrective action to MMS within 30 days of the discovery of the adverse...

  13. 30 CFR 585.816 - What must I do if environmental or other conditions adversely affect a cable, pipeline, or facility?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What must I do if environmental or other conditions adversely affect a cable, pipeline, or facility? 585.816 Section 585.816 Mineral Resources BUREAU... corrective action to BOEM within 30 days of the discovery of the adverse effect. (b) Take remedial action...

  14. 30 CFR 585.816 - What must I do if environmental or other conditions adversely affect a cable, pipeline, or facility?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What must I do if environmental or other conditions adversely affect a cable, pipeline, or facility? 585.816 Section 585.816 Mineral Resources BUREAU... corrective action to BOEM within 30 days of the discovery of the adverse effect. (b) Take remedial action...

  15. A study of different indicators of Maillard reaction with whey proteins and different carbohydrates under adverse storage conditions.

    PubMed

    Leiva, Graciela E; Naranjo, Gabriela B; Malec, Laura S

    2017-01-15

    This study examined different indicators of each stage of Maillard reaction under adverse storage conditions in a system with whey proteins and lactose or glucose. The analysis of lysine loss by the o-phthaldialdehyde method can be considered a good indicator of the early stage, showing considerable differences in reactivity when systems with mono and disaccharides were analyzed. Capillary electrophoresis proved to be a sensitive method for evaluating the extent of glycosylation of the native proteins, providing valuable information when the loss of lysine was not significant. The estimation of the Amadori compound from the determination of total 5-hydroxymethyl-2-furfuraldehyde would have correlate well with reactive lysine content if the advanced stages of the reaction had not been reached. For assessing the occurrence of the intermediate and final stages, the measurement of free 5-hydroxymethyl-2-furfuraldehyde and color, proved not to be suitable for storage conditions. PMID:27542493

  16. Emerging role of angiogenin in stress response and cell survival under adverse conditions

    PubMed Central

    Li, Shuping; Hu, Guo-Fu

    2011-01-01

    Angiogenin (ANG), also known as ribonuclease (RNASE) 5, is a member of the vertebrate-specific, secreted RNASE superfamily. ANG was originally identified as a tumor angiogenic factor, but its biological activity has been extended from inducing angiogenesis to stimulating cell proliferation and more recently, to promoting cell survival. Under growth conditions, ANG is translocated to nucleus where it accumulates in nucleolus and stimulates ribosomal RNA (rRNA) transcription, thus facilitating cell growth and proliferation. Under stress conditions, ANG is accumulated in cytoplasmic compartments and modulates the production of tiRNA, a novel class of small RNA that is derived from tRNA and is induced by stress. tiRNA suppress global protein translation by inhibiting both cap-dependent and -independent translation including that mediated by weak IRESes. However, strong IRES-mediated translation, a mechanism often used by genes involved in pro-survival and anti-apoptosis, is not affected. Thus, ANG-mediated tiRNA reprogram protein translation, save anabolic energy, and promote cell survival. This recently uncovered function of ANG presents a novel mechanism of action in regulating cell growth and survival. PMID:22021078

  17. Performance evaluation of laser scanners through the atmosphere with adverse condition

    NASA Astrophysics Data System (ADS)

    Hespel, L.; Riviere, N.; Huet, T.; Tanguy, B.; Ceolato, R.

    2011-11-01

    Using laser imaging systems to represent 3-D scene becomes a referent prospective technology in the areas of guidance and navigation. Measurements with high spatial resolution for significant range can be achieved, even in degraded visibility conditions such as the Brown-White Out, rain, fog, sandstorms... Moreover, this technology is well suited for assisted perception tasks (access to 3D information) and obstacle detection (telemetry of small objects). For airborne applications, it is very complementary to conventional enhanced vision systems such as Forward Looking Infrared (FLIR) and millimeter wave radar to provide images of land in environments with limited visibility. It also offers a 3D mapping of land or a single location in relation to the environment, which means alone or coupled with others, can realign and secure real-time database of information used such in a synthetic vision system (SVS). The objective of the work is to assess the impact of degraded visibility conditions on the laser radiometric propagation of a 3D laser scanner as they directly influence the performance of the ladar system [1].

  18. Planetary boundary layer energetics simulated from a regional climate model over Europe for present climate and climate change conditions

    NASA Astrophysics Data System (ADS)

    Sánchez, E.; Yagüe, C.; Gaertner, M. A.

    2007-01-01

    This paper presents a description of the planetary boundary layer (PBL) for current (1960-1990) and future (2070-2100) climate periods as obtained from a regional climate model (RCM) centered on the Mediterranean basin. Vertically integrated turbulent kinetic energy (TKEZ) and boundary layer height (z i ) are used to describe PBL energetics. Present climate shows a TKEZ annual cycle with a clear summer maximum for southern regions, while northern regions of Europe exhibit a smoother or even a lack of cycle. Future climate conditions exhibit a similar behaviour, with an increase in the summer maximum peaks. A detailed analysis of summer surface climate change energetics over land shows an increased Bowen ratio and decreases in the evaporative fraction. The enhanced sensible heat flux responsible for these results causes an energy surplus inside the PBL, resulting in increased convective activity and corresponding TKEZ. These results are consistent with temperature increases obtained by several other model simulations, and also indicate that changes in the turbulent transport from the PBL to the free troposphere can affect atmospheric circulations.

  19. Projection of climatic suitability for Aedes albopictus Skuse (Culicidae) in Europe under climate change conditions

    NASA Astrophysics Data System (ADS)

    Fischer, Dominik; Thomas, Stephanie Margarete; Niemitz, Franziska; Reineking, Björn; Beierkuhnlein, Carl

    2011-07-01

    During the last decades the disease vector Aedes albopictus ( Ae. albopictus) has rapidly spread around the globe. The spread of this species raises serious public health concerns. Here, we model the present distribution and the future climatic suitability of Europe for this vector in the face of climate change. In order to achieve the most realistic current prediction and future projection, we compare the performance of four different modelling approaches, differentiated by the selection of climate variables (based on expert knowledge vs. statistical criteria) and by the geographical range of presence records (native range vs. global range). First, models of the native and global range were built with MaxEnt and were either based on (1) statistically selected climatic input variables or (2) input variables selected with expert knowledge from the literature. Native models show high model performance (AUC: 0.91-0.94) for the native range, but do not predict the European distribution well (AUC: 0.70-0.72). Models based on the global distribution of the species, however, were able to identify all regions where Ae. albopictus is currently established, including Europe (AUC: 0.89-0.91). In a second step, the modelled bioclimatic envelope of the global range was projected to future climatic conditions in Europe using two emission scenarios implemented in the regional climate model COSMO-CLM for three time periods 2011-2040, 2041-2070, and 2071-2100. For both global-driven models, the results indicate that climatically suitable areas for the establishment of Ae. albopictus will increase in western and central Europe already in 2011-2040 and with a temporal delay in eastern Europe. On the other hand, a decline in climatically suitable areas in southern Europe is pronounced in the Expert knowledge based model. Our projections appear unaffected by non-analogue climate, as this is not detected by Multivariate Environmental Similarity Surface analysis. The generated risk maps

  20. The brain dynamics of rapid perceptual adaptation to adverse listening conditions.

    PubMed

    Erb, Julia; Henry, Molly J; Eisner, Frank; Obleser, Jonas

    2013-06-26

    Listeners show a remarkable ability to quickly adjust to degraded speech input. Here, we aimed to identify the neural mechanisms of such short-term perceptual adaptation. In a sparse-sampling, cardiac-gated functional magnetic resonance imaging (fMRI) acquisition, human listeners heard and repeated back 4-band-vocoded sentences (in which the temporal envelope of the acoustic signal is preserved, while spectral information is highly degraded). Clear-speech trials were included as baseline. An additional fMRI experiment on amplitude modulation rate discrimination quantified the convergence of neural mechanisms that subserve coping with challenging listening conditions for speech and non-speech. First, the degraded speech task revealed an "executive" network (comprising the anterior insula and anterior cingulate cortex), parts of which were also activated in the non-speech discrimination task. Second, trial-by-trial fluctuations in successful comprehension of degraded speech drove hemodynamic signal change in classic "language" areas (bilateral temporal cortices). Third, as listeners perceptually adapted to degraded speech, downregulation in a cortico-striato-thalamo-cortical circuit was observable. The present data highlight differential upregulation and downregulation in auditory-language and executive networks, respectively, with important subcortical contributions when successfully adapting to a challenging listening situation. PMID:23804092

  1. Slarti: A boundary condition editor for a coupled climate model

    NASA Astrophysics Data System (ADS)

    Mickelson, S. A.; Jacob, R. L.; Pierrehumbert, R.

    2006-12-01

    One of the largest barriers to making climate models more flexible is the difficulty in creating new boundary conditions, especially for "deep time" paleoclimate cases where continents are in different positions. Climate models consist of several mutually-interacting component models and the boundary conditions must be consistent between them. We have developed a program called Slarti which uses a Graphical User Interface and a set of consistency rules to aid researchers in creating new, consistent, boundary condition files for the Fast Ocean Atmosphere Model (FOAM). Users can start from existing mask, topography, or bathymetry data or can build a "world" entirely from scratch (e.g. a single island continent). Once a case has been started, users can modify mask, vegetation, bathymetry, topography, and river flow fields by drawing new data through a "paint" interface. Users activate a synchronization button which goes through the fields to eliminate inconsistencies. When the changes are complete and save is selected, Slarti creates all the necessary files for an initial run of FOAM. The data is edited at the highest resolution (the ocean-land surface in FOAM) and then interpolated to the atmosphere resolution. Slarti was implemented in Java to maintain portability across platforms. We also relied heavily on Java Swing components to create the interface. This allowed us to create an object-oriented interface that could be used on many different systems. Since Slarti allows users to visualize their changes, they are able to see areas that may cause problems when the model is ran. Some examples would be lakes from the river flow field and narrow trenches within the bathymetry. Through different checks and options available through its interface, Slarti makes the process of creating new boundary conditions for FOAM easier and faster while reducing the chance for user errors.

  2. Impacts of peatland forestation on regional climate conditions in Finland

    NASA Astrophysics Data System (ADS)

    Gao, Yao; Markkanen, Tiina; Backman, Leif; Henttonen, Helena M.; Pietikäinen, Joni-Pekka; Laaksonen, Ari

    2014-05-01

    Climate response to anthropogenic land cover change happens more locally and occurs on a shorter time scale than the global warming due to increased GHGs. Over the second half of last Century, peatlands were vastly drained in Finland to stimulate forest growth for timber production. In this study, we investigate the biophysical effects of peatland forestation on near-surface climate conditions in Finland. For this, the regional climate model REMO, developed in Max Plank Institute (currently in Climate Service Center, Germany), provides an effective way. Two sets of 15-year climate simulations were done by REMO, using the historic (1920s; The 1st Finnish National Forest Inventory) and present-day (2000s; the 10th Finnish National Forest Inventory) land cover maps, respectively. The simulated surface air temperature and precipitation were then analyzed. In the most intensive peatland forestation area in Finland, the differences in monthly averaged daily mean surface air temperature show a warming effect around 0.2 to 0.3 K in February and March and reach to 0.5 K in April, whereas a slight cooling effect, less than 0.2 K, is found from May till October. Consequently, the selected snow clearance dates in model gridboxes over that area are advanced 0.5 to 4 days in the mean of 15 years. The monthly averaged precipitation only shows small differences, less than 10 mm/month, in a varied pattern in Finland from April to September. Furthermore, a more detailed analysis was conducted on the peatland forestation area with a 23% decrease in peatland and a 15% increase in forest types. 11 day running means of simulated temperature and energy balance terms, as well as snow depth were averaged over 15 years. Results show a positive feedback induced by peatland forestation between the surface air temperature and snow depth in snow melting period. This is because the warmer temperature caused by lower surface albedo due to more forest in snow cover period leads to a quicker and

  3. The influence of convection parameterisations under alternate climate conditions

    NASA Astrophysics Data System (ADS)

    Rybka, Harald; Tost, Holger

    2013-04-01

    In the last decades several convection parameterisations have been developed to consider the impact of small-scale unresolved processes in Earth System Models associated with convective clouds. Global model simulations, which have been performed under current climate conditions with different convection schemes, significantly differ among each other in the simulated precipitation patterns due to the parameterisation assumptions and formulations, e.g. the simplified treatment of the cloud microphysics. Additionally, the simulated transport of short-lived trace gases strongly depends on the chosen convection parameterisation due to the differences in the vertical redistribution of mass. Furthermore, other meteorological parameters like the temperature or the specific humidity show substantial differences in convectively active regions. This study presents uncertainties of climate change scenarios caused by different convection parameterisations. For this analysis two experiments (reference simulation with a CO2 concentration of 348 ppm; 2xCO2-simulation with a CO2 concentration of 696 ppm) are calculated with the ECHAM/MESSy atmospheric chemistry (EMAC) model applying four different convection schemes (Tiedtke, ECMWF, Emanuel and Zhang-McFarlane - Hack) and two resolutions (T42 and T63), respectively. The results indicate that the equilibrium climate sensitivity is independent of the chosen convection parameterisation. However, the regional temperature increase, induced by a doubling of the carbon dioxide concentration, demonstrates differences of up to a few Kelvin at the surface as well as in the UTLS for the ITCZ region depending on the selected convection parameterisation. The interaction between cloud and convection parameterisations results in a large disagreement of precipitation patterns. Although every 2xCO2 -experiment simulates an increase in global mean precipitation rates, the change of regional precipitation patterns differ widely. Finally, analysing

  4. Hydropower Energy in Lebanon: Adaptation for Changing Climatic Conditions

    NASA Astrophysics Data System (ADS)

    Shaban, A.

    2012-12-01

    The mountainous terrain of Lebanon makes it a climatic barrier that receives clod air masses from the west and condensate them as rain and snow. Hence the average precipitation rate is about 950mm, creating tremendous water sources, but large portion of this water runs to the sea before utilizing it properly. The natural patterns of surface run-off on the mountainous terrain provide a chance to generate hydropower energy. Thus, Lebanon has 17 hydropower stations on 8 rivers. The productivity of these stations averages about 722 GWh, which provide an integral portion of the Lebanese electrical energy. The population growth and the failure of the existing electrical plants to supply adequate energy have been increased in the last few decades. Thus, there is proposition to construct 13 new hydropower plants. However, challenges for generating hydropower energy has been exacerbated; especially in the view of changing climatic conditions, including fluctuations in precipitation regime, which results an obvious decrease in the volume of run-off. This threatens constructed dams for energy generation. Hence, adapting new instrumentations became a necessity mechanism to be applied before proposing new hydropower station in Lebanon. This study will introduce the applicable adaptation tools to be followed in this respect.

  5. Reported respiratory symptoms and adverse home conditions after 9/11 among residents living near the World Trade Center.

    PubMed

    Lin, Shao; Jones, Rena; Reibman, Joan; Bowers, James; Fitzgerald, Edward F; Hwang, Syni-An

    2007-05-01

    This study investigated whether self-reported damage, dust, and odors in homes near the World Trade Center (WTC) after September 11, 2001, were related to increased rates of respiratory symptoms among residents and if multiple sources of exposure were associated with greater health risk. We mailed questionnaires to homes within 1.5 km of the WTC site (affected area) and in upper Manhattan (control area). Surveys asked about respiratory symptoms, unplanned medical visits, physician diagnoses, medication use, and conditions in the home after 9/11. Adverse home conditions were associated with new-onset (i.e., began after 9/11) and persistent (i.e., remained 1 year after 9/11) upper and lower respiratory symptoms in the affected area (Cumulative Incidence Ratios [CIRs] 1.20-1.71). Residents reporting longer duration of dust/odors or multiple sources of exposure had greater risk for symptoms compared to those reporting shorter duration and fewer sources. These data suggest that WTC-related contamination in the home after 9/11 was associated with new and persistent respiratory symptoms among residents living near the site. While we cannot eliminate potential biases related to self-reported data, we took strategies to minimize their impact, and the observed effects are biologically plausible. PMID:17530533

  6. Impact of in-consistency between the climate model and its initial conditions on climate prediction

    NASA Astrophysics Data System (ADS)

    Liu, Xueyuan; Köhl, Armin; Stammer, Detlef; Masuda, Shuhei; Ishikawa, Yoichi; Mochizuki, Takashi

    2016-05-01

    We investigated the influence of dynamical in-consistency of initial conditions on the predictive skill of decadal climate predictions. The investigation builds on the fully coupled global model "Coupled GCM for Earth Simulator" (CFES). In two separate experiments, the ocean component of the coupled model is full-field initialized with two different initial fields from either the same coupled model CFES or the GECCO2 Ocean Synthesis while the atmosphere is initialized from CFES in both cases. Differences between both experiments show that higher SST forecast skill is obtained when initializing with coupled data assimilation initial conditions (CIH) instead of those from GECCO2 (GIH), with the most significant difference in skill obtained over the tropical Pacific at lead year one. High predictive skill of SST over the tropical Pacific seen in CIH reflects the good reproduction of El Niño events at lead year one. In contrast, GIH produces additional erroneous El Niño events. The tropical Pacific skill differences between both runs can be rationalized in terms of the zonal momentum balance between the wind stress and pressure gradient force, which characterizes the upper equatorial Pacific. In GIH, the differences between the oceanic and atmospheric state at initial time leads to imbalance between the zonal wind stress and pressure gradient force over the equatorial Pacific, which leads to the additional pseudo El Niño events and explains reduced predictive skill. The balance can be reestablished if anomaly initialization strategy is applied with GECCO2 initial conditions and improved predictive skill in the tropical Pacific is observed at lead year one. However, initializing the coupled model with self-consistent initial conditions leads to the highest skill of climate prediction in the tropical Pacific by preserving the momentum balance between zonal wind stress and pressure gradient force along the equatorial Pacific.

  7. Icing Conditions Over Northern Eurasia in Changing Climate

    NASA Astrophysics Data System (ADS)

    Bulygina, O.; Arzhanova, N.; Groisman, P. Y.

    2013-12-01

    Climate of the Russian Federation for the national territory. This Reference Book addresses the current state of these weather phenomena. However, the ongoing and projected humidity changes in the high latitudes will strongly affect the circum-polar area (land and ocean) and impact the frequency and intensity of these potentially dangerous weather phenomena across the entire extratropical land area. Therefore the goal of the present study is to quantify icing conditions over the northern Eurasia. Our analysis includes data of 958 Russian stations from 1977 to 2012. Regional analysis of gololed characteristics was carried out using quasi-homogeneous climatic regions. Maps (climatology, trends) are presented mostly for visualization purposes. The area-averaging technique using station values converted to anomalies with respect to a common reference period (in this study, from 1977 to 2012). Anomalies were arithmetically averaged first within 1N x 2E grid cells and thereafter by a weighted average value derived over the quasi-homogeneous climatic regions. This approach provides a more uniform spatial field for averaging.

  8. Adaptation options for wheat in Europe will be limited by increased adverse weather events under climate change.

    PubMed

    Trnka, Miroslav; Hlavinka, Petr; Semenov, Mikhail A

    2015-11-01

    Ways of increasing the production of wheat, the most widely grown cereal crop, will need to be found to meet the increasing demand caused by human population growth in the coming decades. This increase must occur despite the decrease in yield gains now being reported in some regions, increased price volatility and the expected increase in the frequency of adverse weather events that can reduce yields. However, if and how the frequency of adverse weather events will change over Europe, the most important wheat-growing area, has not yet been analysed. Here, we show that the accumulated probability of 11 adverse weather events with the potential to significantly reduce yield will increase markedly across all of Europe. We found that by the end of the century, the exposure of the key European wheat-growing areas, where most wheat production is currently concentrated, may increase more than twofold. However, if we consider the entire arable land area of Europe, a greater than threefold increase in risk was predicted. Therefore, shifting wheat production to new producing regions to reduce the risk might not be possible as the risk of adverse events beyond the key wheat-growing areas increases even more. Furthermore, we found a marked increase in wheat exposure to high temperatures, severe droughts and field inaccessibility compared with other types of adverse events. Our results also showed the limitations of some of the presently debated adaptation options and demonstrated the need for development of region-specific strategies. Other regions of the world could be affected by adverse weather events in the future in a way different from that considered here for Europe. This observation emphasizes the importance of conducting similar analyses for other major wheat regions. PMID:26577595

  9. Adaptation options for wheat in Europe will be limited by increased adverse weather events under climate change

    PubMed Central

    Trnka, Miroslav; Hlavinka, Petr; Semenov, Mikhail A.

    2015-01-01

    Ways of increasing the production of wheat, the most widely grown cereal crop, will need to be found to meet the increasing demand caused by human population growth in the coming decades. This increase must occur despite the decrease in yield gains now being reported in some regions, increased price volatility and the expected increase in the frequency of adverse weather events that can reduce yields. However, if and how the frequency of adverse weather events will change over Europe, the most important wheat-growing area, has not yet been analysed. Here, we show that the accumulated probability of 11 adverse weather events with the potential to significantly reduce yield will increase markedly across all of Europe. We found that by the end of the century, the exposure of the key European wheat-growing areas, where most wheat production is currently concentrated, may increase more than twofold. However, if we consider the entire arable land area of Europe, a greater than threefold increase in risk was predicted. Therefore, shifting wheat production to new producing regions to reduce the risk might not be possible as the risk of adverse events beyond the key wheat-growing areas increases even more. Furthermore, we found a marked increase in wheat exposure to high temperatures, severe droughts and field inaccessibility compared with other types of adverse events. Our results also showed the limitations of some of the presently debated adaptation options and demonstrated the need for development of region-specific strategies. Other regions of the world could be affected by adverse weather events in the future in a way different from that considered here for Europe. This observation emphasizes the importance of conducting similar analyses for other major wheat regions. PMID:26577595

  10. Icing conditions over Northern Eurasia in changing climate

    NASA Astrophysics Data System (ADS)

    Bulygina, Olga N.; Arzhanova, Natalia M.; Groisman, Pavel Ya

    2015-02-01

    Icing conditions, particularly in combination with wind, affect greatly the operation of overhead communication and transmission lines causing serious failures, which result in tremendous economic damage. Icing formation is dangerous to agriculture, forestry, high seas fishery, for land and off coast man-made infrastructure. Quantitative icing characteristics such as weight, thickness, and duration are very important for the economy and human wellbeing when their maximum values exceed certain thresholds. Russian meteorological stations perform both visual and instrumental monitoring of icing deposits. Visual monitoring is ocular estimation of the type and intensity of icing and the date of ice appearance and disappearance. Instrumental monitoring is performed by ice accretion indicator that in addition to the type, intensity and duration of ice deposits reports also their weight and size. We used observations at 958 Russian stations for the period 1977-2013 to analyze changes in the ice formation frequency at individual meteorological stations and on the territory of quasi-homogeneous climatic regions in Russia. It was found that hoar frosts are observed in most parts of Russia, but icing only occurs in European Russia and the Far East. On the Arctic coast of Russia, this phenomenon can even be observed in summer months. Statistically significant decreasing trends in occurrence of icing and hoar frost events are found over most of Russia. An increasing trend in icing weights (IWs) was found in the Atlantic Arctic region in autumn. Statistically significant large negative trends in IWs were found in the Pacific Arctic in winter and spring.

  11. Predicting Low Flow Conditions from Climatic Indices - Indicator-Based Modeling for Climate Change Impact Assessment

    NASA Astrophysics Data System (ADS)

    Fangmann, Anne; Haberlandt, Uwe

    2014-05-01

    In the face of climate change, the assessment of future hydrological regimes has become indispensable in the field of water resources management. Investigation of potential change is vital for proper planning, especially with regard to hydrological extremes. Commonly, projection of future streamflow is done applying process-based hydrological models, using climate model data as input, whose complex model structures generally require excessive amounts of time and effort for set-up and computation. This study aims at identifying practical alternatives to the employment of sophisticated models by considering simpler, yet sufficiently accurate methods for modeling rainfall-runoff relations with regard to hydrological extremes. The focus is thereby put on the prediction of low flow periods, which are, in contrast to flood events, characterized by extended durations and spatial dimensions. The models to be established in this study base on indicators, which characterize both meteorological and hydrological conditions within dry periods. This approach makes direct use of the coupling between atmospheric driving forces and streamflow response with the underlying presumption that low-precipitation and high-evaporation periods result in diminished flow, implying that relationships exist between the properties of both meteorological and hydrological events (duration, volume, severity etc.). Eventually, optimal combinations of meteorological indicators are sought that are suitable to predict various low flow characteristics with satisfactory accuracy. Two approaches for model specification are tested: a) multiple linear regression, and b) Fuzzy logic. The data used for this study are daily time series of mean discharge obtained from 294 gauges with variable record length situated in the federal state of Lower Saxony, Germany, as well as interpolated climate variables available for a period from 1951 to 2011. After extraction of a variety of indicators from the available

  12. Food Security Under Shifting Economic, Demographic, and Climatic Conditions (Invited)

    NASA Astrophysics Data System (ADS)

    Naylor, R. L.

    2013-12-01

    Global demand for food, feed, and fuel will continue to rise in a more populous and affluent world. Meeting this demand in the future will become increasingly challenging with global climate change; when production shocks stemming from climate variability are added to the new mean climate state, food markets could become more volatile. This talk will focus on the interacting market effects of demand and supply for major food commodities, with an eye on climate-related supply trends and shocks. Lessons from historical patterns of climate variability (e.g., ENSO and its global teleconnections) will be used to infer potential food security outcomes in the event of abrupt changes in the mean climate state. Domestic food and trade policy responses to crop output and price volatility in key producing and consuming nations, such as export bans and import tariffs, will be discussed as a potentially major destabilizing force, underscoring the important influence of uncertainty in achieving--or failing to achieve--food security.

  13. Climate change impact on shallow groundwater conditions in Hungary: Conclusions from a regional modelling study

    NASA Astrophysics Data System (ADS)

    Kovács, Attila; Marton, Annamária; Tóth, György; Szöcs, Teodóra

    2016-04-01

    A quantitative methodology has been developed for the calculation of groundwater table based on measured and simulated climate parameters. The aim of the study was to develop a toolset which can be used for the calculation of shallow groundwater conditions for various climate scenarios. This was done with the goal of facilitating the assessment of climate impact and vulnerability of shallow groundwater resources. The simulated groundwater table distributions are representative of groundwater conditions at the regional scale. The introduced methodology is valid for modelling purposes at various scales and thus represents a versatile tool for the assessment of climate vulnerability of shallow groundwater bodies. The calculation modules include the following: 1. A toolset to calculate climate zonation from climate parameter grids, 2. Delineation of recharge zones (Hydrological Response Units, HRUs) based on geology, landuse and slope conditions, 3. Calculation of percolation (recharge) rates using 1D analytical hydrological models, 4. Simulation of the groundwater table using numerical groundwater flow models. The applied methodology provides a quantitative link between climate conditions and shallow groundwater conditions, and thus can be used for assessing climate impacts. The climate data source applied in our calculation comprised interpolated daily climate data of the Central European CARPATCLIM database. Climate zones were determined making use of the Thorntwaite climate zonation scheme. Recharge zones (HRUs) were determined based on surface geology, landuse and slope conditions. The HELP hydrological model was used for the calculation of 1D water balance for hydrological response units. The MODFLOW numerical groundwater modelling code was used for the calculation of the water table. The developed methodology was demonstrated through the simulation of regional groundwater table using spatially averaged climate data and hydrogeological properties for various time

  14. Amplifying Learning through Sites of Pedagogical Practice: A Possible Effect of Working with Disciplinary Technologies in Schools Operating under Adverse Conditions

    ERIC Educational Resources Information Center

    Hayes, Debra

    2005-01-01

    Schools located within communities experiencing high levels of social dislocation, educational disadvantage and student disengagement from learning are working under "adverse conditions". These schools face particular challenges when it comes to stabilising and sustaining wholeschool change aimed at improving students' learning outcomes. In this…

  15. Regional feedbacks under changing climate and land-use conditions

    NASA Astrophysics Data System (ADS)

    Batlle Bayer, L.; van den Hurk, B. J. J. M.; Strengers, B. J.; van Minnen, J. G.

    2012-04-01

    Ecosystem responses to a changing climate and human-induced climate forcings (e.g. deforestation) might amplify (positive feedback) or dampen (negative feedback) the initial climate response. Feedbacks may include the biogeochemical (e.g. carbon cycle) and biogeophysical feedbacks (e.g. albedo and hydrological cycle). Here, we first review the most important feedbacks and put them into the context of a conceptual framework, including the major processes and interactions between terrestrial ecosystems and climate. We explore potential regional feedbacks in four hot spots with pronounced potential changes in land-use/management and local climate: sub-Saharan Africa (SSA), Europe, the Amazon Basin and South and Southeast Asia. For each region, the relevant human-induced climate forcings and feedbacks were identified based on published literature. When evapotranspiration is limited by a soil water deficit, heat waves in Europe are amplified (positive soil moisture-temperature feedback). Drought events in the Amazon lead to further rainfall reduction when water recycling processes are affected (positive soil moisture-precipitation feedback). In SSA, the adoption of irrigation in the commonly rainfed systems can modulate the negative soil moisture-temperature feedback. In contrast, future water shortage in South and Southeast Asia can turn the negative soil moisture-temperature feedback into a positive one. Further research including advanced modeling strategies is needed to isolate the dominant processes affecting the strength and sign of the feedbacks. In addition, the socio-economic dimension needs to be considered in the ecosystems-climate system to include the essential role of human decisions on land-use and land-cover change (LULCC). In this context, enhanced integration between Earth System (ES) and Integrated Assessment (IA) modeling communities is strongly recommended.

  16. Impacts of Hydrologic Model Decision to Water Management Within the San Juan River Basin Under Changing Climate Conditions

    NASA Astrophysics Data System (ADS)

    Piechota, T. C.; Miller, W. P.

    2010-12-01

    A modified version of the U.S. Department of the Interior, Bureau of Reclamation (Reclamation) Colorado River Simulation System (CRSS) is used to evaluate potential impacts of climate change to the San Juan River Basin through 2099. Using temporally disaggregated, bias-corrected spatially downscaled projections of temperature and precipitation, 112 projections of future streamflow for each model were developed using the distributed Variable Infiltration Capacity (VIC) model and the lumped National Weather Service (NWS) River Forecast System (RFS) provided by the Colorado Basin River Forecasting Center. These projections from the VIC model and NWS RFS were then used to force Reclamation’s CRSS model over the San Juan River Basin. On average, inflow into the Navajo Reservoir is approximately 5% higher using inflows derived using the NWS RFS than those inflows developed using the VIC model; however, average inflow over the entire San Juan River Basin is approximately 9% higher using inflows derived using the VIC model than those inflows developed using the NWS RFS. Regulated streamflow to Lake Powell is projected to decrease by up to 39% under changing climate conditions. Overall, there is a higher risk of shortage within the San Juan River Basin using streamflow developed using the NWS RFS model as compared to inflow scenarios developed using the VIC model. Both models project decreased water availability under changing climate conditions within the San Juan River Basin, which may adversely impact water users throughout the Colorado River Basin.

  17. Assessment of mycotoxin risk on corn in the Philippines under current and future climate change conditions.

    PubMed

    Salvacion, Arnold R; Pangga, Ireneo B; Cumagun, Christian Joseph R

    2015-01-01

    This study attempts to assess the risk of mycotoxins (aflatoxins and fumonisins) contamination on corn in the Philippines under current and projected climate change conditions using fuzzy logic methodology based on the published range of temperature and rainfall conditions that favor mycotoxin development. Based on the analysis, projected climatic change will reduce the risk of aflatoxin contamination in the country due to increased rainfall. In the case of fumonisin contamination, most parts of the country are at a very high risk both under current conditions and the projected climate change conditions. PMID:26351797

  18. Genotype and Neuropsychological Response Inhibition as Resilience Promoters for ADHD, ODD, and CD under Conditions of Psychosocial Adversity

    PubMed Central

    Nigg, Joel; Nikolas, Molly; Friderici, Karen; Park, Leeyoung; Zucker, Robert A.

    2008-01-01

    Whereas child personality, IQ, and family factors have been identified as enabling a resilient response to psychosocial adversity, more direct biological resilience factors have been less well delineated. This is particularly so for child ADHD, which has received less attention from a resilience perspective than have associated externalizing disorders. Children from two independent samples were classified as resilient if they avoided developing ADHD, ODD, or CD in the face of family adversity. Two protective factors were examined for their potential relevance to prefrontal brain development: neuropsychological response inhibition, as assessed by the Stop task, and a composite catecholamine genotype risk score. Resilient children were characterized in both samples by more effective response inhibition, although the effect in the second sample was very small. Genotype was measured in Sample 1, and a composite high risk genotype index was developed by summing presence of risk across markers on three genes expressed in prefrontal cortex: dopamine transporter, dopamine D4 receptor, and noradrenergic alpha 2 receptor. Genotype was a reliable resilience indicator against development of ADHD and CD, but not ODD, in the face of psychosocial adversity. Results illustrate potential neurobiological protective factors related to development of prefrontal cortex that may enable children to avoid developing ADHD and CD in the presence of psychosocial adversity. PMID:17705902

  19. Adversity-induced relapse of fear: neural mechanisms and implications for relapse prevention from a study on experimentally induced return-of-fear following fear conditioning and extinction.

    PubMed

    Scharfenort, R; Menz, M; Lonsdorf, T B

    2016-01-01

    The efficacy of current treatments for anxiety disorders is limited by high relapse rates. Relapse of anxiety disorders and addiction can be triggered by exposure to life adversity, but the underlying mechanisms remain unexplored. Seventy-six healthy adults were a priori selected for the presence or absence of adverse experiences during childhood (CA) and recent past (RA; that is, past 12 months). Participants underwent fear conditioning (day 1) and fear extinction and experimental return-of-fear (ROF) induction through reinstatement (a model for adversity-induced relapse; day 2). Ratings, autonomic (skin conductance response) and neuronal activation measures (functional magnetic resonance imaging (fMRI)) were acquired. Individuals exposed to RA showed a generalized (that is, not CS- specific) fear recall and ROF, whereas unexposed individuals showed differential (that is, CS+ specific) fear recall and ROF on an autonomic level despite no group differences during fear acquisition and extinction learning. These group differences in ROF were accompanied by corresponding activation differences in brain areas known to be involved in fear processing and differentiability/generalization of ROF (that is, hippocampus). In addition, dimensional measures of RA, CA and lifetime adversity were negatively correlated with differential skin conductance responses (SCRs) during ROF and hippocampal activation. As discriminating signals of danger and safety, as well as a tendency for overgeneralization, are core features in clinically anxious populations, these deficits may specifically contribute to relapse risk following exposure to adversity, in particular to recent adversity. Hence, our results may provide first and novel insights into the possible mechanisms mediating enhanced relapse risk following exposure to (recent) adversity, which may guide the development of effective pre- and intervention programs. PMID:27434492

  20. Ecosystem resilience despite large-scale altered hydro climatic conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Climate change is predicted to increase both drought frequency and duration, and when coupled with substantial warming, will establish a new hydroclimatological paradigm for many regions. Large-scale, warm droughts have recently impacted North America, Africa, Europe, Amazonia, and Australia result...

  1. Climatic conditions in northern Canada: past and future.

    PubMed

    Prowse, Terry D; Furgal, Chris; Bonsal, Barrie R; Edwards, Thomas W D

    2009-07-01

    This article reviews the historical, instrumental, and future changes in climate for the northern latitudes of Canada. Discussion of historical climate over the last 10 000 years focuses on major climatic shifts including the Medieval Warm Period and the Little Ice Age, and how these changes compare with those most recently experienced during the period of instrumental records. In reference to the latter, details are noted about observed trends in temperature and precipitation that have been recorded over the last half century, which exhibit strong west to east and north to south spatial contrasts. A comprehensive review of future changes is also provided based on outputs from seven atmosphere-ocean global climate models and six emission scenarios. Discussion focuses on annual, seasonal, and related spatial changes for three 30-year periods centered on the 2020s, 2050s, and 2080s. In summary, substantial changes to temperature and precipitation are projected for the Canadian North during the twenty-first century. Although there is considerable variability within the various projections, all scenarios show higher temperature and, for the most part, increasing precipitation over the entire region. PMID:19714958

  2. Measurement of heat stress conditions at cow level and comparison to climate conditions at stationary locations inside a dairy barn.

    PubMed

    Schüller, Laura K; Heuwieser, Wolfgang

    2016-08-01

    The objectives of this study were to examine heat stress conditions at cow level and to investigate the relationship to the climate conditions at 5 different stationary locations inside a dairy barn. In addition, we compared the climate conditions at cow level between primiparous and multiparous cows for a period of 1 week after regrouping. The temperature-humidity index (THI) differed significantly between all stationary loggers. The lowest THI was measured at the window logger in the experimental stall and the highest THI was measured at the central logger in the experimental stall. The THI at the mobile cow loggers was 2·33 THI points higher than at the stationary loggers. Furthermore, the mean daily THI was higher at the mobile cow loggers than at the stationary loggers on all experimental days. The THI in the experimental pen was 0·44 THI points lower when the experimental cow group was located inside the milking parlour. The THI measured at the mobile cow loggers was 1·63 THI points higher when the experimental cow group was located inside the milking parlour. However, there was no significant difference for all climate variables between primiparous and multiparous cows. These results indicate, there is a wide range of climate conditions inside a dairy barn and especially areas with a great distance to a fresh air supply have an increased risk for the occurrence of heat stress conditions. Furthermore, the heat stress conditions are even higher at cow level and cows not only influence their climatic environment, but also generate microclimates within different locations inside the barn. Therefore climate conditions should be obtained at cow level to evaluate the heat stress conditions that dairy cows are actually exposed to. PMID:27600964

  3. Collaborative Research for Water Resource Management under Climate Change Conditions

    NASA Astrophysics Data System (ADS)

    Brundiers, K.; Garfin, G. M.; Gober, P.; Basile, G.; Bark, R. H.

    2010-12-01

    We present an ongoing project to co-produce science and policy called Collaborative Planning for Climate Change: An Integrated Approach to Water-Planning, Climate Downscaling, and Robust Decision-Making. The project responds to motivations related to dealing with sustainability challenges in research and practice: (a) state and municipal water managers seek research that addresses their planning needs; (b) the scientific literature and funding agencies call for more meaningful engagement between science and policy communities, in ways that address user needs, while advancing basic research; and (c) empirical research contributes to methods for the design and implementation of collaborative projects. To understand how climate change might impact water resources and management in the Southwest US, our project convenes local, state, and federal water management practitioners with climate-, hydrology-, policy-, and decision scientists. Three areas of research inform this collaboration: (a) the role of paleo-hydrology in water resources scenario construction; (b) the types of uncertainties that impact decision-making beyond climate and modeling uncertainty; and (c) basin-scale statistical and dynamical downscaling of climate models to generate hydrologic projections for regional water resources planning. The project engages all participants in the research process, from research design to workshops that build capacity for understanding data generation and sources of uncertainty to the discussion of water management decision contexts. A team of “science-practice translators” facilitates the collaboration between academic and professional communities. In this presentation we contextualize the challenges and opportunities of use-inspired science-policy research collaborations by contrasting the initial project design with the process of implementation. We draw from two sources to derive lessons learned: literature on collaborative research, and evaluations provided by

  4. The study of climate suitability for grapevine cropping using ecoclimatic indicators under climatic change conditions in France

    NASA Astrophysics Data System (ADS)

    Garcia de Cortazar-Atauri, I.; Caubel, J.; Cufi, J.; Huard, F.; Launay, M.; deNoblet, N.

    2013-12-01

    Climatic conditions play a fundamental role in the suitability of geographical areas for cropping. In the case of grape, climatic conditions such as water supply and temperatures have an effect of grape quality. In the context of climate change, we could expect changes in overall climatic conditions and so, in grape quality. We proposed to use GETARI (Generic Evaluation Tool of Ecoclimatic Indicators) in order to assess the future climate suitability of two French sites for grape (Vitis vinifera) regarding its quality. GETARI calculates an overall climate suitability index at the annual scale, from a designed evaluation tree. This aggregation tool proposes the major ecophysiological processes taking place during phenological periods, together with the climatic effects that are known to affect their achievement. The effects of climate on the ecophysiological processes are captured by the ecoclimatic indicators, which are agroclimatic indicators calculated over phenological periods. They give information about crop response to climate through ecophysiological or agronomic thresholds. These indicators are normalized and aggregated according to aggregation rules in order to compute an overall climate index. To assess the future climate suitability of two French sites for grape regarding its quality, we designed an evaluation tree from GETARI, by considering the effect of water deficit between flowering and veraison and the effect of water deficit, water excess, heat stress, temperature ranges between day and night, night temperatures and mean temperatures between veraison and harvest. The two sites are located in Burgundy and Rhone valley which are two of the most important vineyards in the world. Ecoclimatic indicators are calculated using phenological cycle of the crop. For this reason we chose Grenache and Pinot Noir as long and short cycle varieties respectively. Flowering, veraison and harvest dates were simulated (Parker et al., 2011; Yiou et al., 2012). Daily

  5. Marine water quality under climate change conditions/scenarios

    NASA Astrophysics Data System (ADS)

    Rizzi, Jonathan; Torresan, Silvia; Critto, Andrea; Zabeo, Alex; Brigolin, Daniele; Carniel, Sandro; Pastres, Roberto; Marcomini, Antonio

    2016-04-01

    The increase of sea temperature and the changes in marine currents are generating impacts on coastal waters such as changes in water biogeochemical and physical parameters (e.g. primary production, pH, salinity) leading to progressive degradation of the marine environment. With the main aim of analysing the potential impacts of climate change on coastal water quality, a Regional Risk Assessment (RRA) methodology was developed and applied to coastal marine waters of the North Adriatic (i.e. coastal water bodies of the Veneto and Friuli Venezia Giulia regions, Italy). RRA integrates the outputs of regional models providing information on macronutrients (i.e. dissolved inorganic nitrogen e reactive phosphorus), dissolved oxygen, pH, salinity and temperature, etc., under future climate change scenarios with site-specific environmental and socio-economic indicators (e.g. biotic index, presence and extension of seagrasses, presence of aquaculture). The presented approach uses Geographic Information Systems to manage, analyse, and visualize data and employs Multi-Criteria Decision Analysis for the integration of stakeholders preferences and experts judgments into the evaluation process. RRA outputs are hazard, exposure, vulnerability, risk and damage maps useful for the identification and prioritization of hot-spot areas and vulnerable targets in the considered region. Therefore, the main aim of this contribution is to apply the RRA methodology to integrate, visualize, and rank according to spatial distribution, physical and chemical data concerning the coastal waters of the North Adriatic Sea in order to predict possible changes of the actual water quality.

  6. Varroa destructor and viruses association in honey bee colonies under different climatic conditions.

    PubMed

    Giacobino, Agostina; Molineri, Ana I; Pacini, Adriana; Fondevila, Norberto; Pietronave, Hernán; Rodríguez, Graciela; Palacio, Alejandra; Bulacio Cagnolo, Natalia; Orellano, Emanuel; Salto, César E; Signorini, Marcelo L; Merke, Julieta

    2016-06-01

    Honey bee colonies are threatened by multiple factors including complex interactions between environmental and diseases such as parasitic mites and viruses. We compared the presence of honeybee-pathogenic viruses and Varroa infestation rate in four apiaries: commercial colonies that received treatment against Varroa and non-treated colonies that did not received any treatment for the last 4 years located in temperate and subtropical climate. In addition, we evaluated the effect of climate and Varroa treatment on deformed wing virus (DWV) amounts. In both climates, DWV was the most prevalent virus, being the only present virus in subtropical colonies. Moreover, colonies from subtropical climate also showed reduced DWV amounts and lower Varroa infestation rates than colonies from temperate climate. Nevertheless, non-treated colonies in both climate conditions are able to survive several years. Environment appears as a key factor interacting with local bee populations and influencing colony survival beyond Varroa and virus presence. PMID:27083139

  7. Analysis of climatic conditions and preliminary assessment of alternative cooling strategies for houses in California transition climate zones

    SciTech Connect

    Huang, Y.J.; Zhang, H.

    1995-07-01

    This is a preliminary scoping study done as part of the {open_quotes}Alternatives to Compressive Cooling in California Transition Climates{close_quotes} project, which has the goal of demonstrating that houses in the transitional areas between the coast and the Central Valley of California do not require air-conditioning if they are properly designed and operated. The first part of this report analyzes the climate conditions within the transitional areas, with emphasis on design rather than seasonal conditions. Transitional climates are found to be milder but more variable than those further inland. The design temperatures under the most stringent design criteria, e.g. 0.1 % annual, are similar to those in the Valley, but significantly lower under more relaxed design criteria, e.g., 2% annual frequency. Transition climates also have large day-night temperature swings, indicating significant potential for night cooling, and wet-bulb depressions in excess of 25 F, indicating good potential for evaporative cooling. The second part of the report is a preliminary assessment using DOE-2 computer simulations of the effectiveness of alternative cooling and control strategies in improving indoor comfort conditions in two conventional Title-24 houses modeled in various transition climate locations. The cooling measures studied include increased insulation, light colors, low-emissivity glazing, window overhangs, and exposed floor slab. The control strategies studied include natural and mechanical ventilation, and direct and two-stage evaporative cooling. The results indicate the cooling strategies all have limited effectiveness, and need to be combined to produce significant improvements in indoor comfort. Natural and forced ventilation provide similar improvements in indoor conditions, but during peak cooling periods, these will still be above the comfort zone. Two-stage evaporative coolers can maintain indoor comfort at all hours, but not so direct evaporative coolers.

  8. Soil organic carbon of European forest soils: current stock and projections under climate change conditions

    NASA Astrophysics Data System (ADS)

    Caddeo, Antonio; Marras, Serena; Spano, Donatella; Sirca, Costantino

    2016-04-01

    Soil organic carbon (SOC) represents the largest terrestrial carbon pool, and it is subjected to climate change impacts. In Europe, a limited number of studies makes a wide-scale comparison of SOC stock and changes under climate change conditions, and most of them are related to agricultural soils. In this work, the SOC stock of the forested areas of Europe (obtained from the CORINE 2006 Land Use Map) was assessed at 1 km resolution using the agro-ecosystem SOC model CENTURY. The results of the model were compared with independent observational datasets (i.e. LUCAS Topsoil Survey Database). In addition, climate simulations (RCPs 4.5 and 8.5) using the CMCC (Euro-Mediterranean Centre on Climate Change) and the CORDEX dataset were used to estimate the SOC changes of these areas under climate change conditions.

  9. Analysis of extreme climatic features over South America from CLARIS-LPB ensemble of regional climate models for future conditions

    NASA Astrophysics Data System (ADS)

    Sanchez, E.; Zaninelli, P.; Carril, A.; Menendez, C.; Dominguez, M.

    2012-04-01

    An ensemble of seven regional climate models (RCM) included in the European CLARIS-LPB project (A Europe-South America Network for Climate Change Assessment and Impact Studies in La Plata Basin) are used to study how some features related to climatic extremes are projected to be changed by the end of XXIst century. These RCMs are forced by different IPCC-AR4 global climate models (IPSL, ECHAM5 and HadCM3), covering three different 30-year periods: present (1960-1990), near future (2010-2040) and distant future (2070-2100), with 50km of horizontal resolution. These regional climate models have previously been forced with ERA-Interim reanalysis, in a consistent procedure with CORDEX (A COordinated Regional climate Downscaling EXperiment) initiative for the South-America domain. The analysis shows a good agreement among them and the available observational databases to describe the main features of the mean climate of the continent. Here we focus our analysis on some topics of interest related to extreme events, such as the development of diagnostics related to dry-spells length, the structure of the frequency distribution functions over several subregions defined by more or less homogeneous climatic conditions (four sub-basins over the La Plata Basin, the southern part of the Amazon basin, Northeast Brazil, and the South Atlantic Convergence Zone (SACZ)), the structure of the annual cycle and their main features and relation with the length of the seasons, or the frequency of anomalous hot or cold events. One shortcoming that must be considered is the lack of observational databases with both time and spatial frequency to validate model outputs. At the same time, one challenging issue of this study is the regional modelling description of a continent where a huge variety of climates are present, from desert to mountain conditions, and from tropical to subtropical regimes. Another basic objective of this preliminary work is also to obtain a measure of the spread among

  10. Catchment sensitivity to changing climate conditions: the importance of landscape characteristic

    NASA Astrophysics Data System (ADS)

    Teutschbein, C.; Karlsen, R.; Grabs, T.; Laudon, H.; Bishop, K. H.

    2014-12-01

    The scientific literature is full of studies analyzing future climate change impacts on hydrology with focus on individual catchments. However, we recently found that hydrologic behavior and specific discharge vary considerably even in neighboring and rather similar catchments under current climate conditions and that these variations are related to landscape characteristics. Therefore we hypothesize that these landscape characteristics also play a fundamental role for the sensitivity of a catchment to changing climate conditions. We analyzed the hydrological response of 14 neighboring catchments in Northern Sweden with slightly different topography, land cover, size and geology. Current (1981-2010) and future (2061-2090) streamflow was simulated with the HBV light model. Climate projections were based on 14 regional climate models (ENSEMBLES EU project) and bias-corrected with a distribution-mapping approach. Our simulations revealed that future spring flood peaks will occur much earlier and decrease by 13 to 32 %, whereas winter base flows will increase slightly. These changes are somewhat expected and mainly triggered by a projected increase in winter temperature, which leads to less snow accumulation on the ground. However, these values also highlight that there is a large variability amongst the catchments in their hydrological response to the same future climate conditions. For example, spring flood peaks in catchments without wetlands decrease by only 13 to 15 %, whereas catchments with wetlands show a spring flood peak reduction of 20 to 32 %. In addition to wetlands, we also identified lakes, peat soils and higher elevations as factors that seem to cause a stronger hydrological response to the climate change signal, whereas catchments dominated by forests, steeper slopes and till soils seem to be less strongly affected by a changing climate. Therefore, our results suggest that the sensitivity of catchments to future climate conditions is strongly linked to

  11. Groundwater recharge simulation under the steady-state and transient climate conditions

    NASA Astrophysics Data System (ADS)

    Pozdniakov, S.; Lykhina, N.

    2010-03-01

    Groundwater recharge simulation under the steady-state and transient climate conditions Diffusive groundwater recharge is a vertical water flux through the water table, i.e. through the boundary between the unsaturated and saturated zones. This flux features temporal and spatial changes due to variations in the climatic conditions, landscape the state of vegetation, and the spatial variability of vadoze zone characteristics. In a changing climate the non-steady state series of climatic characteristics will affect on the groundwater recharge.. A well-tested approach to calculating water flux through the vadoze zone is the application of Richard’s equations for a heterogeneous one-domain porosity continuum with specially formulated atmospheric boundary conditions at the ground surface. In this approach the climatic parameters are reflected in upper boundary conditions, while the recharge series is the flux through the low boundary. In this work developed by authors code Surfbal that simulates water cycle at surface of topsoil to take into account the various condition of precipitation transformation at the surface in different seasons under different vegetation cover including snow accumulation in winter and melting in spring is used to generate upper boundary condition at surface of topsoil for world-wide known Hydrus-1D code (Simunek et al, 2008). To estimate the proposal climate change effect we performed Surfbal and Hydrus simulation using the steady state climatic condition and transient condition due to global warming on example of Moscow region, Russia. The following scenario of climate change in 21 century in Moscow region was selected: the annual temperature will increase on 4C during 100 year and annual precipitation will increase on 10% (Solomon et al, 2007). Within the year the maximum increasing of temperature and precipitation falls on winter time, while in middle of summer temperature will remain almost the same as observed now and monthly

  12. Hydrological Responses to Land-Use Change Scenarios under Constant and Changed Climatic Conditions.

    PubMed

    Zhang, Ling; Nan, Zhuotong; Yu, Wenjun; Ge, Yingchun

    2016-02-01

    This study quantified the hydrological responses to land-use change scenarios in the upper and middle Heihe River basin (HRB), northwest China, under constant and changed climatic conditions by combining a land-use/cover change model (dynamic conversion of land use and its effects, Dyna-CLUE) and a hydrological model (soil and water assessment tool, SWAT). Five land-use change scenarios, i.e., historical trend (HT), ecological protection (EP), strict ecological protection (SEP), economic development (ED), and rapid economic development (RED) scenarios, were established. Under constant climatic condition, hydrological variations are only induced by land-use changes in different scenarios. The changes in mean streamflow at the outlets of the upper and the middle HRB are not pronounced, although the different scenarios produce different outcomes. However, more pronounced changes are observed on a subbasin level. The frequency of extreme flood is projected to decrease under the SEP scenario, while under the other scenarios, no changes can be found. Two emission scenarios (A1B and B1) of three general circulation models (HadCM3, CGCM3, and CCSM3) were employed to generate future possible climatic conditions. Under changed climatic condition, hydrological variations are induced by the combination of land-use and climatic changes. The results indicate that the impacts of land-use changes become secondary when the changed climatic conditions have been considered. The frequencies of extreme flood and drought are projected to decrease and increase, respectively, under all climate scenarios. Although some agreements can be reached, pronounced difference of hydrological responses can be observed for different climate scenarios of different GCMs. PMID:26429363

  13. Hydrological Responses to Land-Use Change Scenarios under Constant and Changed Climatic Conditions

    NASA Astrophysics Data System (ADS)

    Zhang, Ling; Nan, Zhuotong; Yu, Wenjun; Ge, Yingchun

    2016-02-01

    This study quantified the hydrological responses to land-use change scenarios in the upper and middle Heihe River basin (HRB), northwest China, under constant and changed climatic conditions by combining a land-use/cover change model (dynamic conversion of land use and its effects, Dyna-CLUE) and a hydrological model (soil and water assessment tool, SWAT). Five land-use change scenarios, i.e., historical trend (HT), ecological protection (EP), strict ecological protection (SEP), economic development (ED), and rapid economic development (RED) scenarios, were established. Under constant climatic condition, hydrological variations are only induced by land-use changes in different scenarios. The changes in mean streamflow at the outlets of the upper and the middle HRB are not pronounced, although the different scenarios produce different outcomes. However, more pronounced changes are observed on a subbasin level. The frequency of extreme flood is projected to decrease under the SEP scenario, while under the other scenarios, no changes can be found. Two emission scenarios (A1B and B1) of three general circulation models (HadCM3, CGCM3, and CCSM3) were employed to generate future possible climatic conditions. Under changed climatic condition, hydrological variations are induced by the combination of land-use and climatic changes. The results indicate that the impacts of land-use changes become secondary when the changed climatic conditions have been considered. The frequencies of extreme flood and drought are projected to decrease and increase, respectively, under all climate scenarios. Although some agreements can be reached, pronounced difference of hydrological responses can be observed for different climate scenarios of different GCMs.

  14. Is the impact of future climate change on hydro-climatic conditions significant? - A climate change study for an Eastern European catchment area.

    NASA Astrophysics Data System (ADS)

    Pavlik, Dirk; Söhl, Dennis; Bernhofer, Christian

    2014-05-01

    The future change of climatic conditions is, among others, closely linked to future hydrological changes. One important aspect of these issues is the question of future availability of water resources. A changed climatic water balance, as indicator for potential water availability, has far-reaching consequences for the water cycle, hydrological conditions, ecology, water management, the energy business, agriculture and forestry, and for anthropogenic use of the river. We generated regional climate projections via dynamic downscaling for the catchment area of the Western Bug river in the border area of Poland, Belarus, and Ukraine. The hydro-climatic conditions of the past and their projected future changes in the catchment were analyzed based on 2m-temperature, precipitation, potential evaporation and climatic water balance. Up to the end of the century, the used IPCC scenarios B1 and A2 lead to warming for each month in the long-term mean, with highest warming rates in winter. Instead, precipitation does not change in the long-term yearly mean. However, the intra-annual distribution of monthly precipitation sums shifts with an increase in winter and a strong decrease in summer. Combined, this leads to a changed climatic water balance with a stronger deficit in summer and a higher gain in winter. Particular in the south-eastern part of the catchment, the summer deficit cannot be compensated within the annual cycle. It raised the question: are these changes statistically significant and thus robust for use in further impact studies? Using a significance analysis, we found, that climatic changes in temperature, precipitation and potential evaporation and thus the climatic water balance change is most significant for scenario A2 from 2071 to 2100. The temperature changes are significant throughout the year. For the other variables changes are most significant in the late summer months (July, August, and September) and the winter months (December, January, and February

  15. Climate condition in the Central Europe during the Weichselian Ice Sheet according to the Educational Global Climate Modeling Project

    NASA Astrophysics Data System (ADS)

    Szuman, Izabela; Czernecki, Bartosz

    2010-05-01

    The expansion and retreat of the ice sheet is controlled by climate changes, and from the other hand, a huge ice mass influences on the climate in the regional scale. This mechanism is commonly known as the fact but often without making reconstruction by using climatological modeling. The purpose of our study is to reconstruct the climate condition during the Weichselian Ice Sheet in the Central Europe, especially for Poland and surrounded countries. The Global Climate Model (GCM) is made for predicting climate, but simplified version can be useful for reconstructing paleoclimate. Hence, the simple initial conditions and surface data proposed by the Educational version of the GCM was applied. In our study we used a simplified version of the GCM to calculate main climate characteristics within the time limits c. 21 000 BP - 18 000 BP, which has been previously invented on Columbia University. The model is constructed on grid with a horizontal resolution 8° latitude by 10° longitude and was establish for modeling most of weather conditions based on available paleoclimate data. It is possible to estimate the probable climate condition along the southern ice sheets margin on the basis of output from the GCM and GIS modeling techniques. Above the ice mass occurs local high pressure area, which seriously interfered on atmospheric circulation. Whereas the low pressure systems in the southern part of continent may caused permanent barometric situation, which stimulates wind directions as well as the precipitable water available in the mass of air. The climate on the east-south border of ice margin was colder and drier than on the west-south region, where it was more ocean-reliable and gentle with higher temperatures. The differences in temperature between the western and eastern part of the Central Europe reached few centigrade. Against a background of the mean paleoclimatic situation in the Central Europe there is coming out a question about the particular paleoclimate

  16. Evaluation of thermal perception in schoolyards under Mediterranean climate conditions

    NASA Astrophysics Data System (ADS)

    Antoniadis, D.; Katsoulas, N.; Papanastasiou, D.; Christidou, V.; Kittas, C.

    2016-03-01

    The aim of this paper was to study qualitatively and quantitatively the thermal perception and corresponding heat stress conditions that prevail in two schoolyards in a coastal city in central Greece. For this purpose, meteorological parameters (i.e., wind speed, temperature, relative humidity, solar radiation) were recorded at 70 and 55 measuring points in the schoolyards, from 14:00 to 15:30 local time, during May and June of 2011. The measuring points were distributed so as to get measurements at points (a) directly exposed to the sun, (b) under the shadow of trees and building structures, and (c) near building structures. Cluster analysis was applied to group observations and revealed places that are microclimatically homogeneous. Thermal perception and heat stress conditions were assessed by means of the physiologically equivalent temperature (PET, °C), and the results are presented in relevant charts. The impact of material's albedo, radiation's reflection by structures and obstacles, and different tree species on thermal perception and heat stress conditions was also assessed. The analysis showed that trees triggered a reduction of incident solar radiation that ranged between 79 and 94 % depending on tree's species, crown dimension, tree height, and leaf area. PET values were mainly affected by solar radiation and wind speed. Trees caused a reduction of up to 37 % in PET values, while a 1-m s-1 increase in wind speed triggered a reduction of 3.7-5.0 °C in PET value. The effective shading area in the two schoolyards was small, being 27.5 and 11 %. The results of this study could be exploited by urban planning managers when designing or improving the outdoor environment of a school complex.

  17. Evaluation of thermal perception in schoolyards under Mediterranean climate conditions.

    PubMed

    Antoniadis, D; Katsoulas, N; Papanastasiou, D; Christidou, V; Kittas, C

    2016-03-01

    The aim of this paper was to study qualitatively and quantitatively the thermal perception and corresponding heat stress conditions that prevail in two schoolyards in a coastal city in central Greece. For this purpose, meteorological parameters (i.e., wind speed, temperature, relative humidity, solar radiation) were recorded at 70 and 55 measuring points in the schoolyards, from 14:00 to 15:30 local time, during May and June of 2011. The measuring points were distributed so as to get measurements at points (a) directly exposed to the sun, (b) under the shadow of trees and building structures, and (c) near building structures. Cluster analysis was applied to group observations and revealed places that are microclimatically homogeneous. Thermal perception and heat stress conditions were assessed by means of the physiologically equivalent temperature (PET, °C), and the results are presented in relevant charts. The impact of material's albedo, radiation's reflection by structures and obstacles, and different tree species on thermal perception and heat stress conditions was also assessed. The analysis showed that trees triggered a reduction of incident solar radiation that ranged between 79 and 94 % depending on tree's species, crown dimension, tree height, and leaf area. PET values were mainly affected by solar radiation and wind speed. Trees caused a reduction of up to 37 % in PET values, while a 1-m s(-1) increase in wind speed triggered a reduction of 3.7-5.0 °C in PET value. The effective shading area in the two schoolyards was small, being 27.5 and 11 %. The results of this study could be exploited by urban planning managers when designing or improving the outdoor environment of a school complex. PMID:26190284

  18. Early and late maturing grain sorghum under variable climatic conditions in the Texas High Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the Texas High Plains, variable climatic conditions prevail between and within growing seasons. As this area continues to experience drought conditions, and water resources for irrigation become more limited, sorghum [Sorghum bicolor (L.) Moench] production may become a more popular choice to sus...

  19. Climatic conditions governing extensive Azolla bloom during the Middle Eocene

    NASA Astrophysics Data System (ADS)

    Dekker, Rolande; Speelman, Eveline N.; Barke, Judith; Konijnendijk, Tiuri; Sinninge Damste, Jaap S.; Reichart, Gert-Jan

    2010-05-01

    Enormous amounts of intact mega- and microspores from the free floating aquatic fern Azolla were found in sediments recovered during Integrated Ocean Drilling Program expedition 302, indicating that Azolla grew and reproduced in situ in the Eocene Arctic Ocean. In general, the Early/Middle Eocene is characterized by enhanced greenhouse conditions with elevated sea surface temperatures (SSTs) in the Arctic (~10°C), while tropical sea surface temperatures (SSTs) were only a little warmer than today (with a mean annual temperature (MAT) of 32-34 °C) (Pearson et al., 2007). The consequently reduced temperature gradient between the equator and the poles and the presence of freshwater at the North Pole as indicated by the presence of the freshwater fern Azolla (Brinkhuis et al., 2006) provide important boundary conditions for understanding the hydrological cycle and latent heat transport during this interval. Here we reconstruct variations in SST and mean annual air temperature using the TEX86 and MBT temperature proxies for the Azolla interval. Sediments from around the Arctic Basin have been analyzed, including samples from Alaska, the Mackenzie Basin, Greenland (IODP core 913b), and Denmark. Furthermore, a high resolution sea surface temperature record for the Azolla interval has been constructed from sediment samples from the Lomonosov Ridge, showing a cyclic signal. Model experiments have shown that the here confirmed low equator-to-pole temperature gradient modulated the hydrological cycle. Since the growth of Azolla is restricted to low salinity conditions, changes in the hydrological cycle are proposed to coincide with the cyclic occurrence of Azolla throughout the interval. To confirm the overlapping presence of high quantities of Azolla and increased precipitation, changes in the hydrogen cycle are reconstructed by creating a high resolution hydrogen isotope record throughout the interval. By performing compound specific analyses (δD) on terrestrial derived

  20. Attributing Climate Conditions for Stable Malaria Transmission to Human Activity in sub-Saharan Africa

    NASA Astrophysics Data System (ADS)

    Sheldrake, L.; Mitchell, D.; Allen, M. R.

    2015-12-01

    Temperature and precipitation limit areas of stable malaria transmission, but the effects of climate change on the disease remain controversial. Previously, studies have not separated the influence of anthropogenic climate change and natural variability, despite being an essential step in the attribution of climate change impacts. Ensembles of 2900 simulations of regional climate in sub-Saharan Africa for the year 2013, one representing realistic conditions and the other how climate might have been in the absence of human influence, were used to force a P.falciparium climate suitability model developed by the Mapping Malaria Risk in Africa project. Strongest signals were detected in areas of unstable transmission, indicating their heightened sensitivity to climatic factors. Evidently, impacts of human-induced climate change were unevenly distributed: the probability of conditions being suitable for stable malaria transmission were substantially reduced (increased) in the Sahel (Greater Horn of Africa (GHOA), particularly in the Ethiopian and Kenyan highlands). The length of the transmission season was correspondingly shortened in the Sahel and extended in the GHOA, by 1 to 2 months, including in Kericho (Kenya), where the role of climate change in driving recent malaria occurrence is hotly contested. Human-induced warming was primarily responsible for positive anomalies in the GHOA, while reduced rainfall caused negative anomalies in the Sahel. The latter was associated with anthropogenic impacts on the West African Monsoon, but uncertainty in the RCM's ability to reproduce precipitation trends in the region weakens confidence in the result. That said, outputs correspond well with broad-scale changes in observed endemicity, implying a potentially important contribution of anthropogenic climate change to the malaria burden during the past century. Results support the health-framing of climate risk and help indicate hotspots of climate vulnerability, providing

  1. Growing conditions of the Ust'-Emuneret flora and the Santonian-Campanian climate of Chukotka

    NASA Astrophysics Data System (ADS)

    Moiseeva, M. G.

    2015-07-01

    New data on climatic conditions of the Ust'-Emuneret flora growth in the Enmyvaam River basin, Okhotsk-Chukotka volcanic belt, are reported. A great diversity of woody dicot leaves in the studied flora permits for the first time for this region the reconstruction of quantitative paleoclimatic parameters using the CLAMP analysis. On the basis of the available results, the Santonian-Campanian climate of the northern Okhotsk-Chukotka volcanic belt and the adjacent Anadyr-Koryak region is analyzed.

  2. Extreme Air Pollution Conditions Adversely Affect Blood Pressure and Insulin Resistance: The Air Pollution and Cardiometabolic Disease Study.

    PubMed

    Brook, Robert D; Sun, Zhichao; Brook, Jeffrey R; Zhao, Xiaoyi; Ruan, Yanping; Yan, Jianhua; Mukherjee, Bhramar; Rao, Xiaoquan; Duan, Fengkui; Sun, Lixian; Liang, Ruijuan; Lian, Hui; Zhang, Shuyang; Fang, Quan; Gu, Dongfeng; Sun, Qinghua; Fan, Zhongjie; Rajagopalan, Sanjay

    2016-01-01

    Mounting evidence supports that fine particulate matter adversely affects cardiometabolic diseases particularly in susceptible individuals; however, health effects induced by the extreme concentrations within megacities in Asia are not well described. We enrolled 65 nonsmoking adults with metabolic syndrome and insulin resistance in the Beijing metropolitan area into a panel study of 4 repeated visits across 4 seasons since 2012. Daily ambient fine particulate matter and personal black carbon levels ranged from 9.0 to 552.5 µg/m(3) and 0.2 to 24.5 µg/m(3), respectively, with extreme levels observed during January 2013. Cumulative fine particulate matter exposure windows across the prior 1 to 7 days were significantly associated with systolic blood pressure elevations ranging from 2.0 (95% confidence interval, 0.3-3.7) to 2.7 (0.6-4.8) mm Hg per SD increase (67.2 µg/m(3)), whereas cumulative black carbon exposure during the previous 2 to 5 days were significantly associated with ranges in elevations in diastolic blood pressure from 1.3 (0.0-2.5) to 1.7 (0.3-3.2) mm Hg per SD increase (3.6 µg/m(3)). Both black carbon and fine particulate matter were significantly associated with worsening insulin resistance (0.18 [0.01-0.36] and 0.22 [0.04-0.39] unit increase per SD increase of personal-level black carbon and 0.18 [0.02-0.34] and 0.22 [0.08-0.36] unit increase per SD increase of ambient fine particulate matter on lag days 4 and 5). These results provide important global public health warnings that air pollution may pose a risk to cardiometabolic health even at the extremely high concentrations faced by billions of people in the developing world today. PMID:26573709

  3. The effect of abrupt climate changes and climate background conditions in Southern Europe during the last glacial

    NASA Astrophysics Data System (ADS)

    Knorr, Gregor; Martin-Puertas, Celia; Brauer, Achim; Lohmann, Gerrit

    2015-04-01

    The last glacial period is characterized by abrupt and large temperature shifts in Greenland and the North Atlantic realm. Pollen and sediment data from Lago Grande di Monticchio (MON) have demonstrated a clear imprint of these fluctuations operating at millennial time-scales. Interestingly, basic mean environmental condition changes with respect to temperature and precipitation occurred during MIS4, separating warm and dry conditions during MIS5 from relatively cold and humid conditions within MIS3. This general climate background shift is superposed by distinct millennial-scale variability at MON. Using a fully coupled atmosphere-ocean general circulation model applying boundary conditions at 32 ka BP and pre-industrial conditions as a surrogate for MIS3 and MIS5, we have simulated and analysed characteristic changes in Southern Europe during the last glacial. We find that changes in the mean state at MON are mainly related to a partial shift of the North Atlantic deep water (NADW) convection sites from the Nordic Seas to South of Iceland, the presence of the Fennoscandian ice sheet and lower greenhouse gas concentrations. These background characteristics provide the basis for enhanced zonal moisture transport from the eastern North Atlantic to Middle and Southern Europe. Furthermore, simulations of abrupt climate change scenarios show that a deactivation of the convection sites South of Iceland during MIS3 leads to cooler and dryer conditions at MON. Such temperature and precipitation changes are thought to provide a counter-acting effect on woody vegetation and associated pollen signals at MON. This is in contrast to the impact of abrupt climate perturbation scenarios during MIS5, where no significant precipitation changes are detected. Hence, the simulated changes and underlying mechanisms are largely consistent with the recorded proxy evidence with respect to both, mean state and millennial-scale changes.

  4. Modeling of hydrologic conditions and solute movement in processed oil shale waste embankments under simulated climatic conditions

    SciTech Connect

    Reeves, T.L.; Turner, J.P.; Hasfurther, V.R.; Skinner, Q.D.

    1992-06-01

    The scope of this program is to study interacting hydrologic, geotechnical, and chemical factors affecting the behavior and disposal of combusted processed oil shale. The research combines bench-scale testing with large scale research sufficient to describe commercial scale embankment behavior. The large scale approach was accomplished by establishing five lysimeters, each 7.3 {times} 3.0 {times} 3.0 m deep, filled with processed oil shale that has been retorted and combusted by the Lurgi-Ruhrgas (Lurgi) process. Approximately 400 tons of Lurgi processed oil shale waste was provided by RBOSC to carry out this study. Research objectives were designed to evaluate hydrologic, geotechnical, and chemical properties and conditions which would affect the design and performance of large-scale embankments. The objectives of this research are: assess the unsaturated movement and redistribution of water and the development of potential saturated zones and drainage in disposed processed oil shale under natural and simulated climatic conditions; assess the unsaturated movement of solubles and major chemical constituents in disposed processed oil shale under natural and simulated climatic conditions; assess the physical and constitutive properties of the processed oil shale and determine potential changes in these properties caused by disposal and weathering by natural and simulated climatic conditions; assess the use of previously developed computer model(s) to describe the infiltration, unsaturated movement, redistribution, and drainage of water in disposed processed oil shale; evaluate the stability of field scale processed oil shale solid waste embankments using computer models.

  5. Modeling of hydrologic conditions and solute movement in processed oil shale waste embankments under simulated climatic conditions

    SciTech Connect

    Reeves, T.L.; Turner, J.P.; Hasfurther, V.R.; Skinner, Q.D.

    1992-06-01

    The scope of this program is to study interacting hydrologic, geotechnical, and chemical factors affecting the behavior and disposal of combusted processed oil shale. The research combines bench-scale testing with large scale research sufficient to describe commercial scale embankment behavior. The large scale approach was accomplished by establishing five lysimeters, each 7.3 [times] 3.0 [times] 3.0 m deep, filled with processed oil shale that has been retorted and combusted by the Lurgi-Ruhrgas (Lurgi) process. Approximately 400 tons of Lurgi processed oil shale waste was provided by RBOSC to carry out this study. Research objectives were designed to evaluate hydrologic, geotechnical, and chemical properties and conditions which would affect the design and performance of large-scale embankments. The objectives of this research are: assess the unsaturated movement and redistribution of water and the development of potential saturated zones and drainage in disposed processed oil shale under natural and simulated climatic conditions; assess the unsaturated movement of solubles and major chemical constituents in disposed processed oil shale under natural and simulated climatic conditions; assess the physical and constitutive properties of the processed oil shale and determine potential changes in these properties caused by disposal and weathering by natural and simulated climatic conditions; assess the use of previously developed computer model(s) to describe the infiltration, unsaturated movement, redistribution, and drainage of water in disposed processed oil shale; evaluate the stability of field scale processed oil shale solid waste embankments using computer models.

  6. Antagonistic Pleiotropy at the Human IL6 Promoter Confers Genetic Resilience to the Pro-Inflammatory Effects of Adverse Social Conditions in Adolescence

    PubMed Central

    Cole, Steven W.; Arevalo, Jesusa M. G.; Manu, Kavya; Telzer, Eva H.; Kiang, Lisa; Bower, Julienne E.; Irwin, Michael R.; Fuligni, Andrew J.

    2013-01-01

    The authors tested the evolutionary genetic hypothesis that the functional form of an asymmetrically risky Gene × Environment interaction will differ as a function of age-related antagonistic pleiotropy (i.e., show opposite effects in young vs. old individuals). Previous studies have identified a polymorphism in the human IL6 promoter (rs1800795; IL6 –174 G/C) that interacts with adverse socioenvironmental conditions to promote chronic inflammation in older adults (elevated C-reactive protein). This study identifies a protective effect of the same polymorphism in 17- to 19-year-old adolescents confronting socioeconomic adversity. Over 60% of the environmental risk contribution to the IL6 × Socioeconomic Status interaction could be accounted for by interpersonal stress and adult role burden. Thus, the IL6 –174G allele does not represent an undifferentiated risk factor but instead sensitizes inflammatory biology to socioenvironmental conditions, conferring either genetic vulnerability or resilience depending on the developmental “somatic environment” that interacts with social conditions to influence gene expression. PMID:21639625

  7. Key factors affecting urban runoff pollution under cold climatic conditions

    NASA Astrophysics Data System (ADS)

    Valtanen, Marjo; Sillanpää, Nora; Setälä, Heikki

    2015-10-01

    Urban runoff contains various pollutants and has the potential of deteriorating the quality of aquatic ecosystems. In this study our objective is to shed light on the factors that control the runoff water quality in urbanized catchments. The effects of runoff event characteristics, land use type and catchment imperviousness on event mass loads (EML) and event mean concentrations (EMC) were studied during warm and cold periods in three study catchments (6.1, 6.5 and 12.6 ha in size) in the city of Lahti, Finland. Runoff and rainfall were measured continuously for two years at each catchment. Runoff samples were taken for total nutrients (tot-P and tot-N), total suspended solids (TSS), heavy metals (Zn, Cr, Al, Co, Ni, Cu, Pb, Mn) and total organic carbon (TOC). Stepwise multiple linear regression analysis (SMLR) was used to identify general relationships between the following variables: event water quality, runoff event characteristics and catchment characteristics. In general, the studied variables explained 50-90% of the EMLs but only 30-60% of the EMCs, with runoff duration having an important role in most of the SMLR models. Mean runoff intensity or peak flow was also often included in the runoff quality models. Yet, the importance (being the first, second or third best) and role (negative or positive impact) of the explanatory variables varied between the cold and warm period. Land use type often explained cold period concentrations, but imperviousness alone explained EMCs weakly. As for EMLs, the influence of imperviousness and/or land use was season and pollutant dependent. The study suggests that pollutant loads can be - throughout the year - adequately predicted by runoff characteristics given that seasonal differences are taken into account. Although pollutant concentrations were sensitive to variation in seasonal and catchment conditions as well, the accurate estimation of EMCs would require a more complete set of explanatory factors than used in this

  8. Egg phenotype matching by cuckoos in relation to discrimination by hosts and climatic conditions

    PubMed Central

    Avilés, Jesús M.; Vikan, Johan R.; Fossøy, Frode; Antonov, Anton; Moksnes, Arne; Røskaft, Eivin; Shykoff, Jacqui A.; Møller, Anders P.; Stokke, Bård G.

    2012-01-01

    Although parasites and their hosts often coexist in a set of environmentally differentiated populations connected by gene flow, few empirical studies have considered a role of environmental variation in shaping correlations between traits of hosts and parasites. Here, we studied for the first time the association between the frequency of adaptive parasitic common cuckoo Cuculus canorus phenotypes in terms of egg matching and level of defences exhibited by its reed warbler Acrocephalus scirpaceus hosts across seven geographically distant populations in Europe. We also explored the influence of spring climatic conditions experienced by cuckoos and hosts on cuckoo–host egg matching. We found that between-population differences in host defences against cuckoos (i.e. rejection rate) covaried with between-population differences in degree of matching. Between-population differences in host egg phenotype were associated with between-population differences in parasitism rate and spring climatic conditions, but not with host level of defences. Between-population differences in cuckoo egg phenotype covaried with between-population differences in host defences and spring climatic conditions. However, differences in host defences still explained differences in mimicry once differences in climatic conditions were controlled, suggesting that selection exerted by host defences must be strong relative to selection imposed by climatic factors on egg phenotypes. PMID:22237911

  9. Catchment Sensitivity to Changing Climate Conditions: Does the Landscape Control Hydrological Responses?

    NASA Astrophysics Data System (ADS)

    Quesada Montano, B.; Teutschbein, C.; Grabs, T.; Karlsen, R.; Laudon, H.; Bishop, K. H.

    2015-12-01

    It has long been recognized that streamflow-generating processes are not only dependent on climatic conditions, but also affected by physical catchment properties such as topography, geology, soils and land cover. We hypothesize that these landscape characteristics do not only lead to highly variable hydrologic behavior of rather similar catchments under the same stationary climate conditions, but that they also play a fundamental role for the sensitivity of a catchment to a changing climate. A multi-model ensemble based on 15 regional climate models was combined with a multi-catchment approach to explore the hydrologic sensitivity of 14 partially nested and rather similar catchments in Northern Sweden to changing climate conditions and the importance of small-scale spatial variability. Current (1981-2010) and future (2061-2090) streamflow was simulated with the HBV model. As expected, projected increases in temperature and precipitation resulted in increased total available streamflow, with lower spring and summer flows, but substantially higher winter streamflow. Furthermore, significant changes in flow durations with lower chances of both high and low flows can be expected in boreal Sweden in the future. This overall trend in projected streamflow pattern changes was comparable among the analyzed catchments while the magnitude of change differed considerably. This suggests that catchments belonging to the same region can show distinctly different degrees of hydrological responses to the same external climate change signal. We reason that differences in spatially distributed physical catchment properties at smaller scales are not only of great importance for current streamflow behavior, but also play a major role as first-order control for the sensitivity of catchments to changing climate conditions.

  10. Catchment Sensitivity to Changing Climate Conditions: The Importance of Landscape Characteristics

    NASA Astrophysics Data System (ADS)

    Teutschbein, Claudia; Karlsen, Reinert; Grabs, Thomas; Laudon, Hjalmar; Bishop, Kevin

    2015-04-01

    The scientific literature is full of studies analyzing future climate change impacts on hydrology with focus on individual catchments. We recently found, however, that hydrologic behavior and specific discharge vary considerably even in neighboring and rather similar catchments under current climate conditions and that these variations are related to landscape characteristics. Therefore we hypothesize that these landscape characteristics also play a fundamental role for the sensitivity of a catchment to changing climate conditions. We analyzed the hydrological response of 14 partially nested catchments in Northern Sweden with slightly different topography, land cover, size and geology. Current (1981-2010) and future (2061-2090) streamflows were simulated with the hydrological model HBV light based on 15 regional climate model projections that were bias-corrected with a distribution-mapping approach. Our simulations revealed that - in a future climate- the total annual streamflow will be higher, spring flood peaks will occur earlier and decrease considerably, whereas winter base flows will more than double. These changes are somewhat expected and mainly triggered by a projected increase in winter temperature, which leads to less snow accumulation on the ground. However, our results also show that there is a large variability amongst these catchments in their hydrological response to the same future climate conditions. We identified wetlands, lakes, peat soils and higher elevations as factors that had a stronger effect on spring floods, whereas catchments dominated by forests, steeper slopes and till soils showed stronger responses in winter base flows and total annual streamflow. Therefore, our results suggest that the sensitivity of catchments to future climate conditions is strongly linked to landscape characteristics and also depends on the streamflow characteristic as well as season analyzed.

  11. Sensitivity of Pliocene climate simulations in MRI-CGCM2.3 to respective boundary conditions

    NASA Astrophysics Data System (ADS)

    Kamae, Youichi; Yoshida, Kohei; Ueda, Hiroaki

    2016-08-01

    Accumulations of global proxy data are essential steps for improving reliability of climate model simulations for the Pliocene warming climate. In the Pliocene Model Intercomparison Project phase 2 (PlioMIP2), a part project of the Paleoclimate Modelling Intercomparison Project phase 4, boundary forcing data have been updated from the PlioMIP phase 1 due to recent advances in understanding of oceanic, terrestrial and cryospheric aspects of the Pliocene palaeoenvironment. In this study, sensitivities of Pliocene climate simulations to the newly archived boundary conditions are evaluated by a set of simulations using an atmosphere-ocean coupled general circulation model, MRI-CGCM2.3. The simulated Pliocene climate is warmer than pre-industrial conditions for 2.4 °C in global mean, corresponding to 0.6 °C warmer than the PlioMIP1 simulation by the identical climate model. Revised orography, lakes, and shrunk ice sheets compared with the PlioMIP1 lead to local and remote influences including snow and sea ice albedo feedback, and poleward heat transport due to the atmosphere and ocean that result in additional warming over middle and high latitudes. The amplified higher-latitude warming is supported qualitatively by the proxy evidences, but is still underestimated quantitatively. Physical processes responsible for the global and regional climate changes should be further addressed in future studies under systematic intermodel and data-model comparison frameworks.

  12. A vulnerability driven approach to identify adverse climate and land use change combinations for critical hydrologic indicator thresholds: Application to a watershed in Pennsylvania, USA

    NASA Astrophysics Data System (ADS)

    Singh, R.; Wagener, T.; Crane, R.; Mann, M. E.; Ning, L.

    2014-04-01

    Large uncertainties in streamflow projections derived from downscaled climate projections of precipitation and temperature can render such simulations of limited value for decision making in the context of water resources management. New approaches are being sought to provide decision makers with robust information in the face of such large uncertainties. We present an alternative approach that starts with the stakeholder's definition of vulnerable ranges for relevant hydrologic indicators. Then the modeled system is analyzed to assess under what conditions these thresholds are exceeded. The space of possible climates and land use combinations for a watershed is explored to isolate subspaces that lead to vulnerability, while considering model parameter uncertainty in the analysis. We implement this concept using classification and regression trees (CART) that separate the input space of climate and land use change into those combinations that lead to vulnerability and those that do not. We test our method in a Pennsylvania watershed for nine ecological and water resources related streamflow indicators for which an increase in temperature between 3°C and 6°C and change in precipitation between -17% and 19% is projected. Our approach provides several new insights, for example, we show that even small decreases in precipitation (˜5%) combined with temperature increases greater than 2.5°C can push the mean annual runoff into a slightly vulnerable regime. Using this impact and stakeholder driven strategy, we explore the decision-relevant space more fully and provide information to the decision maker even if climate change projections are ambiguous.

  13. Foliar photochemical processes and carbon metabolism under favourable and adverse winter conditions in a Mediterranean mixed forest, Catalonia (Spain)

    NASA Astrophysics Data System (ADS)

    Sperlich, D.; Chang, C. T.; Peñuelas, J.; Gracia, C.; Sabaté, S.

    2014-06-01

    Evergreen trees in the Mediterranean region must cope with a wide range of environmental stresses from summer drought to winter cold. The mildness of Mediterranean winters can periodically lead to favourable environmental conditions above the threshold for a positive carbon balance, benefitting evergreen woody species more than deciduous ones. The comparatively lower solar energy input in winter decreases the foliar light saturation point. This leads to a higher susceptibility to photoinhibitory stress especially when chilly (< 12 °C) or freezing temperatures (< 0 °C) coincide with clear skies and relatively high solar irradiances. Nonetheless, the advantage of evergreen species that are able to photosynthesize all year round where a significant fraction can be attributed to winter months, compensates for the lower carbon uptake during spring and summer in comparison to deciduous species. We investigated the ecophysiological behaviour of three co-occurring mature evergreen tree species (Quercus ilex L., Pinus halepensis Mill., and Arbutus unedo L.) during a period of mild winter conditions and their responses to a sudden cold period. The state of the photosynthetic machinery in both periods was thus tested by estimating the foliar photosynthetic potential with CO2 response curves in parallel with chlorophyll fluorescence measurements. The studied evergreen tree species benefited strongly from mild winter conditions by exhibiting extraordinarily high photosynthetic potentials similar to those under spring conditions. A sudden period of frost, however, negatively affected the photosynthetic apparatus, leading to significant decreases in key physiological parameters such as the maximum carboxylation velocity (Vc, max), the maximum photosynthetic electron transport rate (Jmax), and the optimal fluorometric quantum yield of photosystem II (Fv/Fm). This change persisted for several weeks after the cold period despite the recovery of the temperature to the conditions

  14. Foliar photochemical processes and carbon metabolism under favourable and adverse winter conditions in a Mediterranean mixed forest, Catalonia (Spain)

    NASA Astrophysics Data System (ADS)

    Sperlich, D.; Chang, C. T.; Peñuelas, J.; Gracia, C.; Sabaté, S.

    2014-10-01

    Evergreen trees in the Mediterranean region must cope with a wide range of environmental stresses from summer drought to winter cold. The mildness of Mediterranean winters can periodically lead to favourable environmental conditions above the threshold for a positive carbon balance, benefitting evergreen woody species more than deciduous ones. The comparatively lower solar energy input in winter decreases the foliar light saturation point. This leads to a higher susceptibility to photoinhibitory stress especially when chilly (< 12 °C) or freezing temperatures (< 0 °C) coincide with clear skies and relatively high solar irradiances. Nonetheless, the advantage of evergreen species that are able to photosynthesize all year round where a significant fraction can be attributed to winter months, compensates for the lower carbon uptake during spring and summer in comparison to deciduous species. We investigated the ecophysiological behaviour of three co-occurring mature evergreen tree species (Quercus ilex L., Pinus halepensis Mill., and Arbutus unedo L.). Therefore, we collected twigs from the field during a period of mild winter conditions and after a sudden cold period. After both periods, the state of the photosynthetic machinery was tested in the laboratory by estimating the foliar photosynthetic potential with CO2 response curves in parallel with chlorophyll fluorescence measurements. The studied evergreen tree species benefited strongly from mild winter conditions by exhibiting extraordinarily high photosynthetic potentials. A sudden period of frost, however, negatively affected the photosynthetic apparatus, leading to significant decreases in key physiological parameters such as the maximum carboxylation velocity (Vc, max), the maximum photosynthetic electron transport rate (Jmax), and the optimal fluorometric quantum yield of photosystem II (Fv/Fm). The responses of Vc, max and Jmax were highly species specific, with Q. ilex exhibiting the highest and P

  15. Modeling the effect of adverse environmental conditions and clothing on temperature rise in a human body exposed to radio frequency electromagnetic fields.

    PubMed

    Moore, Stephen M; McIntosh, Robert L; Iskra, Steve; Wood, Andrew W

    2015-02-01

    This study considers the computationally determined thermal profile of a fully clothed, finely discretized, heterogeneous human body model, subject to the maximum allowable reference level for a 1-GHz radio frequency electromagnetic field for a worker, and also subject to adverse environmental conditions, including high humidity and high ambient temperature. An initial observation is that while electromagnetic fields at the occupational safety limit will contribute an additional thermal load to the tissues, and subsequently, cause an elevated temperature, the magnitude of this effect is far outweighed by that due to the conditions including the ambient temperature, relative humidity, and the type of clothing worn. It is envisaged that the computational modeling approach outlined in this paper will be suitably modified in future studies to evaluate the thermal response of a body at elevated metabolic rates, and for different body shapes and sizes including children and pregnant women. PMID:25314694

  16. Environmental Risk of Climate Change and Groundwater Abstraction on Ecological Conditions in a Danish Catchment

    NASA Astrophysics Data System (ADS)

    Seaby, L. P.; Boegh, E.; Jensen, N. H.

    2014-12-01

    The Danish drinking water supply is sourced almost entirely from groundwater. Balancing water abstraction demands and the ecological conditions in streams is one of the major challenges for water resource managers. With projected climate change, characterised by increased annual temperature, precipitation, and evapotranspiration rates for Denmark, the impact to low flows and groundwater levels are especially of interest, as they relate to aquatic habitat and nitrate leaching, respectively. On the island Sjælland, which includes urban and agricultural regions, a doubling of groundwater abstraction rates has been proposed in selected areas to meet water resource demands. This study evaluates the risk to stream ecological conditions for a lowland Danish catchment under multiple scenarios of climate change and groundwater abstraction. Projections of future climate (i.e. precipitation, temperature, reference evapotranspiration) come from the ENSEMBLES climate modelling project. Climate variables from 11 climate models are first bias corrected with a distribution based scaling (DBS) method (Seaby et al., 2013) and then used to force hydrological simulations of stream discharge, groundwater recharge, and nitrate leaching from the root zone under present (1991-2010) and future (2071-2100) climate conditions. Hydrological modelling utilises a sequential coupling methodology with DAISY, a one dimensional crop model describing soil water dynamics in the root zone, and MIKE SHE, a distributed groundwater-surface water model which the National Water Resources Model (DK-model) is set up in (Henriksen et al., 2003). We find low flow and annual discharge to be most impacted by scenarios of climate change, with high variation across climate models (+/- 40% change). Doubling of current groundwater abstraction rates reduces annual discharge by approximately 20%, with higher reductions to low flows seen around 40%. The combined effects of climate change and increased groundwater

  17. Ecoclimatic indicators to study crop suitability in present and future climatic conditions

    NASA Astrophysics Data System (ADS)

    Caubel, Julie; Garcia de Cortazar Atauri, Inaki; Huard, Frédéric; Launay, Marie; Ripoche, Dominique; Gouache, David; Bancal, Marie-Odile; Graux, Anne-Isabelle; De Noblet, Nathalie

    2013-04-01

    Climate change is expected to affect both regional and global food production through changes in overall agroclimatic conditions. It is therefore necessary to develop simple tools of crop suitability diagnosis in a given area so that stakeholders can envisage land use adaptations under climate change conditions. The most common way to investigate potential impacts of climate on the evolution of agrosystems is to make use of an array of agroclimatic indicators, which provide synthetic information derived from climatic variables and calculated within fixed periods (i.e. January first - 31th July). However, the information obtained during these periods does not enable to take account of the plant response to climate. In this work, we present some results of the research program ORACLE (Opportunities and Risks of Agrosystems & forests in response to CLimate, socio-economic and policy changEs in France (and Europe). We proposed a suite of relevant ecoclimatic indicators, based on temperature and rainfall, in order to evaluate crop suitability for both present and new climatic conditions. Ecoclimatic indicators are agroclimatic indicators (e.g., grain heat stress) calculated during specific phenological phases so as to take account of the plant response to climate (e.g., the grain filling period, flowering- harvest). These indicators are linked with the ecophysiological processes they characterize (for e.g., the grain filling). To represent this methodology, we studied the suitability of winter wheat in future climatic conditions through three distinct French sites, Toulouse, Dijon and Versailles. Indicators have been calculated using climatic data from 1950 to 2100 simulated by the global climate model ARPEGE forced by a greenhouse effect corresponding to the SRES A1B scenario. The Quantile-Quantile downscaling method was applied to obtain data for the three locations. Phenological stages (emergence, ear 1 cm, flowering, beginning of grain filling and harvest) have been

  18. CMIP5 simulated climate conditions of the Greater Horn of Africa (GHA). Part II: projected climate

    NASA Astrophysics Data System (ADS)

    Otieno, Vincent O.; Anyah, R. O.

    2013-10-01

    This is the second of the two-part paper series on the analysis and evaluation of the Fifth phase of Coupled Model Intercomparison Project (CMIP5) simulation of contemporary climate as well as IPCC, AR5 Representative Concentrations Pathways (RCP), 4.5 and 8.5 scenarios projections of the Greater Horn of Africa (GHA) Climate. In the first part (Otieno and Anyah in Clim Dyn, 2012) we focused on the historical simulations, whereas this second part primarily focuses on future projections based on the two scenarios. Six Earth System Models (ESMs) from CMIP5 archive have been used to characterize projected changes in seasonal and annual mean precipitation, temperature and the hydrological cycle by the middle of twenty-first century over the GHA region, based on IPCC, 5th Assessment Report (AR5) RCP4.5 and RCP8.5 scenarios. Nearly all the models outputs analyzed reproduce the correct mean annual cycle of precipitation, with some biases among the models in capturing the correct peak of precipitation cycle, more so, March-April-May (MAM) seasonal rainfall over the equatorial GHA region. However, there is significant variation among models in projected precipitation anomalies, with some models projecting an average increase as others project a decrease in precipitation during different seasons. The ensemble mean of the ESMs indicates that the GHA region has been experiencing a steady increase in both precipitation and temperature beginning in the early 1980s and 1970s respectively in both RCP4.5 and RCP8.5 scenarios. Going by the ensemble means, temperatures are projected to steadily increase uniformly in all the seasons at a rate of 0.3/0.5 °C/decade under RCP4.5/8.5 scenarios over northern GHA region leading to an approximate temperature increase of 2/3 °C by the middle of the century. On the other hand, temperatures will likely increase at a rate of 0.3/0.4 °C/decade under RCP4.5/8.5 scenarios in both equatorial and southern GHA region leading to an approximate

  19. Assessment of production risks for winter wheat in different German regions under climate change conditions

    NASA Astrophysics Data System (ADS)

    Kersebaum, K. C.; Gandorfer, M.; Wegehenkel, M.

    2012-04-01

    The study shows climate change impacts on wheat production in selected regions across Germany. To estimate yield and economic effects the agro-ecosystem model HERMES was used. The model performed runs using 2 different releases of the model WETTREG providing statistically downscaled climate change scenarios for the weather station network of the German Weather Service. Simulations were done using intersected GIS information on soil types and land use identifying the most relevant sites for wheat production. The production risks for wheat yields at the middle of this century were compared to a reference of the present climate. The irrigation demand was determined by the model using an automatic irrigation mode. Production risks with and without irrigation were assessed and the economic feasibility to reduce production risks by irrigation was evaluated. Costs and benefits were compared. Additionally, environmental effects, e.g. groundwater recharge and nitrogen emissions were assessed for irrigated and rain fed systems. Results show that positive and negative effects of climate change occur within most regions depending on the site conditions. Water holding capacity and groundwater distance were the most important factors which determined the vulnerability of sites. Under climate change condition in the middle of the next century we can expect especially at sites with low water holding capacity decreasing average gross margins, higher production risks and a reduced nitrogen use efficiency under rainfed conditions. Irrigation seems to be profitable and risk reducing at those sites, provided that water for irrigation is available. Additionally, the use of irrigation can also increase nitrogen use efficiency which reduced emissions by leaching. Despite the site conditions results depend strongly on the used regional climate scenario and the model approach to consider the effect of elevated CO2 in the atmosphere.

  20. Middle Pliocene vegetation: Reconstructions, paleoclimatic inferences, and boundary conditions for climate modeling

    USGS Publications Warehouse

    Thompson, R.S.; Fleming, R.F.

    1996-01-01

    The general characteristics of global vegetation during the middle Pliocene warm period can be reconstructed from fossil pollen and plant megafossil data. The largest differences between Pliocene vegetation and that of today occurred at high latitudes in both hemispheres, where warming was pronounced relative to today. In the Northern Hemisphere coniferous forests lived in the modern tundra and polar desert regions, whereas in the Southern Hemisphere southern beech apparently grew in coastal areas of Antarctica. Pliocene middle latitude vegetation differed less, although moister-than-modern conditions supported forest and woodland growth in some regions now covered by steppe or grassland. Pliocene tropical vegetation reflects essentially modern conditions in some regions and slightly cooler-than-or warmer-than- modern climates in other areas. Changes in topography induced by tectonics may be responsible for many of the climatic changes since the Pliocene in both middle and lower latitudes. However, the overall latitudinal progression of climatic conditions on land parallels that seen in the reconstruction of middle Pliocene sea-surface temperatures. Pliocene paleovegetational data was employed to construct a 2????2?? global grid of estimated mid-Pliocene vegetational cover for use as boundary conditions for numerical General Circulation Model simulations of middle Pliocene climates. Continental outlines and topography were first modified to represent the Pliocene landscape on the 2????2?? grid. A modern 1????1?? vegetation grid was simplified and mapped on this Pliocene grid, and then modified following general geographic trends evident in the Pliocene paleovegetation data set.

  1. One-against-All Weighted Dynamic Time Warping for Language-Independent and Speaker-Dependent Speech Recognition in Adverse Conditions

    PubMed Central

    Zhang, Xianglilan; Sun, Jiping; Luo, Zhigang

    2014-01-01

    Considering personal privacy and difficulty of obtaining training material for many seldom used English words and (often non-English) names, language-independent (LI) with lightweight speaker-dependent (SD) automatic speech recognition (ASR) is a promising option to solve the problem. The dynamic time warping (DTW) algorithm is the state-of-the-art algorithm for small foot-print SD ASR applications with limited storage space and small vocabulary, such as voice dialing on mobile devices, menu-driven recognition, and voice control on vehicles and robotics. Even though we have successfully developed two fast and accurate DTW variations for clean speech data, speech recognition for adverse conditions is still a big challenge. In order to improve recognition accuracy in noisy environment and bad recording conditions such as too high or low volume, we introduce a novel one-against-all weighted DTW (OAWDTW). This method defines a one-against-all index (OAI) for each time frame of training data and applies the OAIs to the core DTW process. Given two speech signals, OAWDTW tunes their final alignment score by using OAI in the DTW process. Our method achieves better accuracies than DTW and merge-weighted DTW (MWDTW), as 6.97% relative reduction of error rate (RRER) compared with DTW and 15.91% RRER compared with MWDTW are observed in our extensive experiments on one representative SD dataset of four speakers' recordings. To the best of our knowledge, OAWDTW approach is the first weighted DTW specially designed for speech data in adverse conditions. PMID:24520317

  2. One-against-all weighted dynamic time warping for language-independent and speaker-dependent speech recognition in adverse conditions.

    PubMed

    Zhang, Xianglilan; Sun, Jiping; Luo, Zhigang

    2014-01-01

    Considering personal privacy and difficulty of obtaining training material for many seldom used English words and (often non-English) names, language-independent (LI) with lightweight speaker-dependent (SD) automatic speech recognition (ASR) is a promising option to solve the problem. The dynamic time warping (DTW) algorithm is the state-of-the-art algorithm for small foot-print SD ASR applications with limited storage space and small vocabulary, such as voice dialing on mobile devices, menu-driven recognition, and voice control on vehicles and robotics. Even though we have successfully developed two fast and accurate DTW variations for clean speech data, speech recognition for adverse conditions is still a big challenge. In order to improve recognition accuracy in noisy environment and bad recording conditions such as too high or low volume, we introduce a novel one-against-all weighted DTW (OAWDTW). This method defines a one-against-all index (OAI) for each time frame of training data and applies the OAIs to the core DTW process. Given two speech signals, OAWDTW tunes their final alignment score by using OAI in the DTW process. Our method achieves better accuracies than DTW and merge-weighted DTW (MWDTW), as 6.97% relative reduction of error rate (RRER) compared with DTW and 15.91% RRER compared with MWDTW are observed in our extensive experiments on one representative SD dataset of four speakers' recordings. To the best of our knowledge, OAWDTW approach is the first weighted DTW specially designed for speech data in adverse conditions. PMID:24520317

  3. Collaborative Research. Quantifying Climate Feedbacks of the Terrestrial Biosphere under Thawing Permafrost Conditions in the Arctic

    SciTech Connect

    Zhuang, Qianlai; Schlosser, Courtney; Melillo, Jerry; Walter, Katey

    2015-09-15

    Our overall goal is to quantify the potential for threshold changes in natural emission rates of trace gases, particularly methane and carbon dioxide, from pan-arctic terrestrial systems under the spectrum of anthropogenically-forced climate warming, and the conditions under which these emissions provide a strong feedback mechanism to global climate warming. This goal is motivated under the premise that polar amplification of global climate warming will induce widespread thaw and degradation of the permafrost, and would thus cause substantial changes to the landscape of wetlands and lakes, especially thermokarst (thaw) lakes, across the Arctic. Through a suite of numerical experiments that encapsulate the fundamental processes governing methane emissions and carbon exchanges – as well as their coupling to the global climate system - we intend to test the following hypothesis in the proposed research: There exists a climate warming threshold beyond which permafrost degradation becomes widespread and stimulates large increases in methane emissions (via thermokarst lakes and poorly-drained wetland areas upon thawing permafrost along with microbial metabolic responses to higher temperatures) and increases in carbon dioxide emissions from well-drained areas. Besides changes in biogeochemistry, this threshold will also influence global energy dynamics through effects on surface albedo, evapotranspiration and water vapor. These changes would outweigh any increased uptake of carbon (e.g. from peatlands and higher plant photosynthesis) and would result in a strong, positive feedback to global climate warming.

  4. Hydrological response to changing climate conditions: Spatial streamflow variability in the boreal region

    NASA Astrophysics Data System (ADS)

    Teutschbein, Claudia; Grabs, Thomas; Karlsen, Reinert H.; Laudon, Hjalmar; Bishop, Kevin

    2016-04-01

    It has long been recognized that streamflow-generating processes are not only dependent on climatic conditions, but also affected by physical catchment properties such as topography, geology, soils and land cover. We hypothesize that these landscape characteristics do not only lead to highly variable hydrologic behavior of rather similar catchments under the same stationary climate conditions (Karlsen et al., 2014), but that they also play a fundamental role for the sensitivity of a catchment to a changing climate (Teutschbein et al., 2015). A multi-model ensemble based on 15 regional climate models was combined with a multi-catchment approach to explore the hydrologic sensitivity of 14 partially nested and rather similar catchments in Northern Sweden to changing climate conditions and the importance of small-scale spatial variability. Current (1981-2010) and future (2061-2090) streamflow was simulated with the HBV model. As expected, projected increases in temperature and precipitation resulted in increased total available streamflow, with lower spring and summer flows, but substantially higher winter streamflow. Furthermore, significant changes in flow durations with lower chances of both high and low flows can be expected in boreal Sweden in the future. This overall trend in projected streamflow pattern changes was comparable among the analyzed catchments while the magnitude of change differed considerably. This suggests that catchments belonging to the same region can show distinctly different degrees of hydrological responses to the same external climate change signal. We reason that differences in spatially distributed physical catchment properties at smaller scales are not only of great importance for current streamflow behavior, but also play a major role as first-order control for the sensitivity of catchments to changing climate conditions. References Karlsen, R.H., T. Grabs, K. Bishop, H. Laudon, and J. Seibert (2014). Landscape controls on

  5. Effects of climate on the productivity of desert truffles beneath hyper-arid conditions.

    PubMed

    Bradai, Lyès; Bissati, Samia; Chenchouni, Haroun; Amrani, Khaled

    2015-07-01

    Desert truffles are edible hypogenous fungi that are very well adapted to conditions of aridity in arid and semi-arid regions. This study aims to highlight the influence of climatic factors on the productivity of desert truffles under hyper-arid climatic conditions of the Sahara Desert in Algeria, with assumptions that the more varying climatic factors, mainly rainfall, are more crucial for the development and production of desert truffles. At seven separate sites, desert truffles were collected by systematic sampling between 2006 and 2012. The effects of climate parameters of each site on the productivities (g/ha/year) of desert truffle species were tested using generalized linear models (GLMs). The annual mean of the total production recorded for all three harvested species (Terfezia arenaria, Terfezia claveryi, and Tirmania nivea) was 785.43 ± 743.39 g/ha. Tirmania nivea was commonly present over the sampled sites with an occurrence of 70 ± 10.1%. GLMs revealed that total and specific productivities were closely positively related to autumnal precipitations occurring during October-December, which is the critical pre-breeding period for both desert truffles and host plant species. The other climatic parameters have statistically no effect on the annual variation of desert truffle productivity. PMID:25164975

  6. Crash testing hydrological models in contrasted climate conditions: An experiment on 216 Australian catchments

    NASA Astrophysics Data System (ADS)

    Coron, L.; AndréAssian, V.; Perrin, C.; Lerat, J.; Vaze, J.; Bourqui, M.; Hendrickx, F.

    2012-05-01

    This paper investigates the actual extrapolation capacity of three hydrological models in differing climate conditions. We propose a general testing framework, in which we perform series of split-sample tests, testing all possible combinations of calibration-validation periods using a 10 year sliding window. This methodology, which we have called the generalized split-sample test (GSST), provides insights into the model's transposability over time under various climatic conditions. The three conceptual rainfall-runoff models yielded similar results over a set of 216 catchments in southeast Australia. First, we assessed the model's efficiency in validation using a criterion combining the root-mean-square error and bias. A relation was found between this efficiency and the changes in mean rainfall (P) but not with changes in mean potential evapotranspiration (PE) or air temperature (T). Second, we focused on average runoff volumes and found that simulation biases are greatly affected by changes in P. Calibration over a wetter (drier) climate than the validation climate leads to an overestimation (underestimation) of the mean simulated runoff. We observed different magnitudes of these models deficiencies depending on the catchment considered. Results indicate that the transfer of model parameters in time may introduce a significant level of errors in simulations, meaning increased uncertainty in the various practical applications of these models (flow simulation, forecasting, design, reservoir management, climate change impact assessments, etc.). Testing model robustness with respect to this issue should help better quantify these uncertainties.

  7. Humpback whale diets respond to variance in ocean climate and ecosystem conditions in the California Current.

    PubMed

    Fleming, Alyson H; Clark, Casey T; Calambokidis, John; Barlow, Jay

    2016-03-01

    Large, migratory predators are often cited as sentinel species for ecosystem processes and climate-related changes, but their utility as indicators is dependent upon an understanding of their response to environmental variability. Documentation of the links between climate variability, ecosystem change and predator dynamics is absent for most top predators. Identifying species that may be useful indicators and elucidating these mechanistic links provides insight into current ecological dynamics and may inform predictions of future ecosystem responses to climatic change. We examine humpback whale response to environmental variability through stable isotope analysis of diet over a dynamic 20-year period (1993-2012) in the California Current System (CCS). Humpback whale diets captured two major shifts in oceanographic and ecological conditions in the CCS. Isotopic signatures reflect a diet dominated by krill during periods characterized by positive phases of the North Pacific Gyre Oscillation (NPGO), cool sea surface temperature (SST), strong upwelling and high krill biomass. In contrast, humpback whale diets are dominated by schooling fish when the NPGO is negative, SST is warmer, seasonal upwelling is delayed and anchovy and sardine populations display increased biomass and range expansion. These findings demonstrate that humpback whales trophically respond to ecosystem shifts, and as a result, their foraging behavior is a synoptic indicator of oceanographic and ecological conditions across the CCS. Multi-decadal examination of these sentinel species thus provides insight into biological consequences of interannual climate fluctuations, fundamental to advancing ecosystem predictions related to global climate change. PMID:26599719

  8. Impact of climatic conditions on the design of a water treatment plant

    NASA Astrophysics Data System (ADS)

    Arregoitia, C.; Mesa, M. P.

    2012-04-01

    The abundance or scarcity of resources causes enormous problems for populations and societies. They mark the direction of the development that a society will take. Water imbalances, may distort optimal environmental and socioeconomic conditions of the food production. Water scarcity may limit food production and supply, putting pressure on food prices and increasing countries' dependence on food imports. Rising demand for food caused by growing populations and shifting diets, production shortfall in some countries, increased costs for key agricultural inputs and meat supply (driven in turn by energy costs), bioenergy-related incentives in some countries and possible financial speculation have all contributed to the steep rises in food prices. According to United Nations Over the past century world water withdrawals increased almost twice as fast as population growth and an increasing number of regions are chronically water short. Climate change has been defined as a change in the statistical properties of the climate system when considered over long periods of time, regardless of cause. Different factors can shape the climate forces or mechanisms and impact the food production system such as the cattle production field. This paper considers the step by step design and implementation of a water treatment plant of a community cattle farm located in Jadacaquiva under changing climatic conditions. The byproducts of the cattle, as well as the community can also have an impact depending on the decisions taken for the plant. Keywords: water, climate change, treatment plant, food scarcity

  9. Effects of climate on the productivity of desert truffles beneath hyper-arid conditions

    NASA Astrophysics Data System (ADS)

    Bradai, Lyès; Bissati, Samia; Chenchouni, Haroun; Amrani, Khaled

    2015-07-01

    Desert truffles are edible hypogenous fungi that are very well adapted to conditions of aridity in arid and semi-arid regions. This study aims to highlight the influence of climatic factors on the productivity of desert truffles under hyper-arid climatic conditions of the Sahara Desert in Algeria, with assumptions that the more varying climatic factors, mainly rainfall, are more crucial for the development and production of desert truffles. At seven separate sites, desert truffles were collected by systematic sampling between 2006 and 2012. The effects of climate parameters of each site on the productivities (g/ha/year) of desert truffle species were tested using generalized linear models (GLMs). The annual mean of the total production recorded for all three harvested species ( Terfezia arenaria, Terfezia claveryi, and Tirmania nivea) was 785.43 ± 743.39 g/ha. Tirmania nivea was commonly present over the sampled sites with an occurrence of 70 ± 10.1 %. GLMs revealed that total and specific productivities were closely positively related to autumnal precipitations occurring during October-December, which is the critical pre-breeding period for both desert truffles and host plant species. The other climatic parameters have statistically no effect on the annual variation of desert truffle productivity.

  10. Plant nutrients do not covary with soil nutrients under changing climatic conditions

    NASA Astrophysics Data System (ADS)

    Luo, Wentao; Elser, James J.; Lü, Xiao-Tao; Wang, Zhengwen; Bai, Edith; Yan, Caifeng; Wang, Chao; Li, Mai-He; Zimmermann, Niklaus E.; Han, Xingguo; Xu, Zhuwen; Li, Hui; Wu, Yunna; Jiang, Yong

    2015-08-01

    Nitrogen (N) and phosphorus (P) play vital roles in plant growth and development. Yet how climate regimes and soil fertility influence plant N and P stoichiometry is not well understood, especially in the belowground plant parts. Here we investigated plant aboveground and belowground N and P concentrations ([N] and [P]) and their stoichiometry in three dominant genera along a 2200 km long climatic gradient in northern China. Results showed that temperature explained more variation of [N] and [P] in C4 plants, whereas precipitation exerted a stronger influence on [N] and [P] in C3 plants. Both plant aboveground and belowground [N] and [P] increased with decreasing precipitation, and increasing temperatures yet were negatively correlated with soil [N] and [P]. Plant N:P ratios were unrelated with all climate and soil variables. Plant aboveground and belowground [N] followed an allometric scaling relationship, but the allocation of [P] was isometric. These results imply that internal processes stabilize plant N:P ratios and hence tissue N:P ratios may not be an effective parameter for predicting plant nutrient limitation. Our results also imply that past positive relationships between plant and nutrient stocks may be challenged under changing climatic conditions. While any modeling would need to be able to replicate currently observed relationships, it is conceivable that some relationships, such as those between temperature or rainfall and carbon:nutrient ratios, should be different under changing climatic conditions.

  11. Storage of milk powders under adverse conditions. 2. Influence on the content of water-soluble vitamins.

    PubMed

    Ford, J E; Hurrell, R F; Finot, P A

    1983-05-01

    Storage of milk powder under unfavourable conditions accelerates the normally slow deterioration in nutritional quality. The effects of such storage on the water-soluble vitamin composition were examined. (a) Spray-dried whole milk containing 25 g water/kg was stored at 60 degrees and 70 degrees and sampled weekly to 9 weeks. (b) Spray-dried whole milk and skimmed milk were adjusted to contain 40 and 100 g water/kg and stored at 37 degrees in nitrogen and in oxygen. Samples were taken for analysis at intervals during storage. The samples were analysed for eight B-complex vitamins and ascorbic acid, and also for total lysine, 'reactive lysine' and 'lysine as lactulosyl-lysine'. Storage at 60 degrees caused rapid destruction of folic acid (53% loss at 4 weeks) and slower loss of thiamin, vitamin B6 and pantothenic acid (18% at 8 weeks). There was no change in the content of riboflavin, biotin, nicotinic acid and vitamin B12. At 70 degrees the rate of destruction of the four labile vitamins was much increased; 18% or less survived at 4 weeks. At 37 degrees and 40 g water/kg there was little change in total and 'reactive' lysine during storage for 57 d. Lactulosyl-lysine was demonstrably present but at low concentration. There was considerable loss of folate (72%) and ascorbate (91%) during storage for 30 d in O2, but no significant loss in N2. Thiamin fell by approximately 12% in 57 d, equally in O2 and N2. The content of the remaining vitamins was unchanged. At 100 g water/kg there were progressive Maillard changes. During 27 d in N2 the colour changed from cream to pale brown, but in O2 there was no perceptible colour change. Total lysine fell by 20% in 27 d, and 'reactive lysine' by 30%. Folate was stable during 16 d in N2, but largely (94%) destroyed in O2. Ascorbic acid was also destroyed in N2 as in O2. Thiamin fell by 41% in 27 d, equally in O2 and N2. Vitamin B6 was more labile, especially in N2, falling by 71% in 16 d. With skimmed-milk powder containing 100

  12. Trophic interactions between viruses, bacteria and nanoflagellates under various nutrient conditions and simulated climate change.

    PubMed

    Bouvy, M; Bettarel, Y; Bouvier, C; Domaizon, I; Jacquet, S; Le Floc'h, E; Montanié, H; Mostajir, B; Sime-Ngando, T; Torréton, J P; Vidussi, F; Bouvier, T

    2011-07-01

    Population dynamics in the microbial food web are influenced by resource availability and predator/parasitism activities. Climatic changes, such as an increase in temperature and/or UV radiation, can also modify ecological systems in many ways. A series of enclosure experiments was conducted using natural microbial communities from a Mediterranean lagoon to assess the response of microbial communities to top-down control [grazing by heterotrophic nanoflagellates (HNF), viral lysis] and bottom-up control (nutrients) under various simulated climatic conditions (temperature and UV-B radiations). Different biological assemblages were obtained by separating bacteria and viruses from HNF by size fractionation which were then incubated in whirl-Pak bags exposed to an increase of 3°C and 20% UV-B above the control conditions for 96 h. The assemblages were also provided with an inorganic and organic nutrient supply. The data show (i) a clear nutrient limitation of bacterial growth under all simulated climatic conditions in the absence of HNF, (ii) a great impact of HNF grazing on bacteria irrespective of the nutrient conditions and the simulated climatic conditions, (iii) a significant decrease in burst size (BS) (number of intracellular lytic viruses per bacterium) and a significant increase of VBR (virus to bacterium ratio) in the presence of HNF, and (iv) a much larger temperature effect than UV-B radiation effect on the bacterial dynamics. These results show that top-down factors, essentially HNF grazing, control the dynamics of the lagoon bacterioplankton assemblage and that short-term simulated climate changes are only a secondary effect controlling microbial processes. PMID:21605305

  13. The uncertainty cascade in flood risk assessment under changing climatic conditions - the Biala Tarnowska case study

    NASA Astrophysics Data System (ADS)

    Doroszkiewicz, Joanna; Romanowicz, Renata

    2016-04-01

    Uncertainty in the results of the hydraulic model is not only associated with the limitations of that model and the shortcomings of data. An important factor that has a major impact on the uncertainty of the flood risk assessment in a changing climate conditions is associated with the uncertainty of future climate scenarios (IPCC WG I, 2013). Future climate projections provided by global climate models are used to generate future runoff required as an input to hydraulic models applied in the derivation of flood risk maps. Biala Tarnowska catchment, situated in southern Poland is used as a case study. Future discharges at the input to a hydraulic model are obtained using the HBV model and climate projections obtained from the EUROCORDEX project. The study describes a cascade of uncertainty related to different stages of the process of derivation of flood risk maps under changing climate conditions. In this context it takes into account the uncertainty of future climate projections, an uncertainty of flow routing model, the propagation of that uncertainty through the hydraulic model, and finally, the uncertainty related to the derivation of flood risk maps. One of the aims of this study is an assessment of a relative impact of different sources of uncertainty on the uncertainty of flood risk maps. Due to the complexity of the process, an assessment of total uncertainty of maps of inundation probability might be very computer time consuming. As a way forward we present an application of a hydraulic model simulator based on a nonlinear transfer function model for the chosen locations along the river reach. The transfer function model parameters are estimated based on the simulations of the hydraulic model at each of the model cross-section. The study shows that the application of the simulator substantially reduces the computer requirements related to the derivation of flood risk maps under future climatic conditions. Acknowledgements: This work was supported by the

  14. Climatic conditions cause complex patterns of covariation between demographic traits in a long-lived raptor.

    PubMed

    Herfindal, Ivar; van de Pol, Martijn; Nielsen, Jan T; Sæther, Bernt-Erik; Møller, Anders P

    2015-05-01

    Environmental variation can induce life-history changes that can last over a large part of the lifetime of an organism. If multiple demographic traits are affected, expected changes in climate may influence environmental covariances among traits in a complex manner. Thus, examining the consequences of environmental fluctuations requires that individual information at multiple life stages is available, which is particularly challenging in long-lived species. Here, we analyse how variation in climatic conditions occurring in the year of hatching of female goshawks Accipiter gentilis (L.) affects age-specific variation in demographic traits and lifetime reproductive success (LRS). LRS decreased with increasing temperature in April in the year of hatching, due to lower breeding frequency and shorter reproductive life span. In contrast, the probability for a female to successfully breed was higher in years with a warm April, but lower LRS of the offspring in these years generated a negative covariance among fecundity rates among generations. The mechanism by which climatic conditions generated cohort effects was likely through influencing the quality of the breeding segment of the population in a given year, as the proportion of pigeons in the diet during the breeding period was positively related to annual and LRS, and the diet of adult females that hatched in warm years contained fewer pigeons. Climatic conditions experienced during different stages of individual life histories caused complex patterns of environmental covariance among demographic traits even across generations. Such environmental covariances may either buffer or amplify impacts of climate change on population growth, emphasizing the importance of considering demographic changes during the complete life history of individuals when predicting the effect of climatic change on population dynamics of long-lived species. PMID:25403010

  15. Thermal performance of a Concrete Cool Roof under different climatic conditions of Mexico

    DOE PAGESBeta

    Hernández-Pérez, I.; Álvarez, G.; Gilbert, H.; Xamán, J.; Chávez, Y.; Shah, B.

    2014-11-27

    A cool roof is an ordinary roof with a reflective coating on the exterior surface which has a high solar reflectance and high thermal emittance. These properties let the roof keep a lower temperature than a standard roof under the same conditions. In this work, the thermal performance of a concrete roof with and without insulation and with two colors has been analyzed using the finite volume method. The boundary conditions of the external roof surface were taken from hourly averaged climatic data of four cities. For the internal surface, it is considered that the building is air-conditioned and themore » inside air has a constant temperature. The interior surface temperature and the heat flux rates into the roofs were obtained for two consecutive days in order to assess the benefits of a cool roofs in different climates.« less

  16. Thermal performance of a Concrete Cool Roof under different climatic conditions of Mexico

    SciTech Connect

    Hernández-Pérez, I.; Álvarez, G.; Gilbert, H.; Xamán, J.; Chávez, Y.; Shah, B.

    2014-11-27

    A cool roof is an ordinary roof with a reflective coating on the exterior surface which has a high solar reflectance and high thermal emittance. These properties let the roof keep a lower temperature than a standard roof under the same conditions. In this work, the thermal performance of a concrete roof with and without insulation and with two colors has been analyzed using the finite volume method. The boundary conditions of the external roof surface were taken from hourly averaged climatic data of four cities. For the internal surface, it is considered that the building is air-conditioned and the inside air has a constant temperature. The interior surface temperature and the heat flux rates into the roofs were obtained for two consecutive days in order to assess the benefits of a cool roofs in different climates.

  17. Projections of climate conditions that increase coral disease susceptibility and pathogen abundance and virulence

    NASA Astrophysics Data System (ADS)

    Maynard, Jeffrey; van Hooidonk, Ruben; Eakin, C. Mark; Puotinen, Marjetta; Garren, Melissa; Williams, Gareth; Heron, Scott F.; Lamb, Joleah; Weil, Ernesto; Willis, Bette; Harvell, C. Drew

    2015-07-01

    Rising sea temperatures are likely to increase the frequency of disease outbreaks affecting reef-building corals through impacts on coral hosts and pathogens. We present and compare climate model projections of temperature conditions that will increase coral susceptibility to disease, pathogen abundance and pathogen virulence. Both moderate (RCP 4.5) and fossil fuel aggressive (RCP 8.5) emissions scenarios are examined. We also compare projections for the onset of disease-conducive conditions and severe annual coral bleaching, and produce a disease risk summary that combines climate stress with stress caused by local human activities. There is great spatial variation in the projections, both among and within the major ocean basins, in conditions favouring disease development. Our results indicate that disease is as likely to cause coral mortality as bleaching in the coming decades. These projections identify priority locations to reduce stress caused by local human activities and test management interventions to reduce disease impacts.

  18. A new approach to mapping permafrost and change incorporating uncertainties in ground conditions and climate projections

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Olthof, I.; Fraser, R.; Wolfe, S. A.

    2014-11-01

    Spatially detailed information on permafrost distribution and change with climate is important for land use planning, infrastructure development, and environmental assessments. However, the required soil and surficial geology maps in the North are coarse, and projected climate scenarios vary widely. Considering these uncertainties, we propose a new approach to mapping permafrost distribution and change by integrating remote sensing data, field measurements, and a process-based model. Land cover types from satellite imagery are used to capture the general land conditions and to improve the resolution of existing permafrost maps. For each land cover type, field observations are used to estimate the probabilities of different ground conditions. A process-based model is used to quantify the evolution of permafrost for each ground condition under three representative climate scenarios (low, medium, and high warming). From the model results, the probability of permafrost occurrence and the most likely permafrost conditions are determined. We apply this approach at 20 m resolution to a large area in Northwest Territories, Canada. Mapped permafrost conditions are in agreement with field observations and other studies. The data requirements, model robustness, and computation time are reasonable, and this approach may serve as a practical means to mapping permafrost and changes at high resolution in other regions.

  19. A New Approach to Mapping Permafrost and Change Incorporating Uncertainties in Ground Conditions and Climate Projections

    NASA Astrophysics Data System (ADS)

    Zhang, Y.

    2014-12-01

    Spatially detailed information on permafrost distribution and change with climate is important for land-use planning, infrastructure development and environmental assessments. However, the required soil and surficial geology maps in the North are coarse, and projected climate scenarios vary widely. Considering these uncertainties, we propose a new approach to mapping permafrost distribution and change by integrating remote sensing data, field measurements, and a process-based model. Land-cover types from satellite imagery are used to capture the general land conditions and to improve the resolution of existing permafrost maps. For each land-cover type, field observations are used to estimate the probability of different ground conditions. A process-based model is used to quantify the evolution of permafrost for each ground condition under three representative climate scenarios (low, medium and high warming). From the model results, the probability of permafrost occurrence and the most likely permafrost conditions are determined (Fig. 1). We apply this approach at 20 m resolution to a large area in Northwest Territories, Canada. Mapped permafrost conditions are in agreement with field observations and other studies. The data requirements, model robustness and computation time are reasonable, and this approach may serve as a practical means to mapping permafrost and changes at high resolution in other regions.

  20. A new approach to mapping permafrost and change incorporating uncertainties in ground conditions and climate projections

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Olthof, I.; Fraser, R.; Wolfe, S. A.

    2014-04-01

    Spatially detailed information on permafrost distribution and change with climate is important for land-use planning and for environmental and ecological assessments. However, the required soil and surficial geology maps in the north are coarse, and projected climate scenarios vary widely. Considering these uncertainties, we propose a new approach to mapping permafrost distribution and change by integrating remote sensing data, field measurements, and a process-based model. Land-cover types from satellite imagery are used to capture the general land conditions and to improve the resolution of existing permafrost maps. For each land-cover type, field observations are used to estimate the probability of different ground conditions. A process-based model is used to quantify the evolution of permafrost for each ground condition under three representative climate scenarios (low, medium and high warming). From the model results, the probability of permafrost occurrence and the most likely permafrost conditions are determined. We apply this approach at 20 m resolution to a large area in Northwest Territories, Canada. Mapped permafrost conditions are in agreement with field observations and other studies. The data requirements, model robustness and computation time are reasonable, and this approach may serve as a practical means to mapping permafrost and changes at high resolution in other regions.

  1. Effects of baseline conditions on the simulated hydrologic response to projected climate change

    USGS Publications Warehouse

    Koczot, Kathryn M.; Markstrom, Steven L.; Hay, Lauren E.

    2011-01-01

    Changes in temperature and precipitation projected from five general circulation models, using one late-twentieth-century and three twenty-first-century emission scenarios, were downscaled to three different baseline conditions. Baseline conditions are periods of measured temperature and precipitation data selected to represent twentieth-century climate. The hydrologic effects of the climate projections are evaluated using the Precipitation-Runoff Modeling System (PRMS), which is a watershed hydrology simulation model. The Almanor Catchment in the North Fork of the Feather River basin, California, is used as a case study. Differences and similarities between PRMS simulations of hydrologic components (i.e., snowpack formation and melt, evapotranspiration, and streamflow) are examined, and results indicate that the selection of a specific time period used for baseline conditions has a substantial effect on some, but not all, hydrologic variables. This effect seems to be amplified in hydrologic variables, which accumulate over time, such as soil-moisture content. Results also indicate that uncertainty related to the selection of baseline conditions should be evaluated using a range of different baseline conditions. This is particularly important for studies in basins with highly variable climate, such as the Almanor Catchment.

  2. Climate phase drives canopy condition in a large semi-arid floodplain forest.

    PubMed

    Wen, Li; Saintilan, Neil

    2015-08-15

    To maintain and restore the ecological integrity of floodplains, allocating water for environmental benefits (i.e. environmental water) is widely practised globally. To efficiently manage the always limited environmental water, there is pressing need to advance our understanding of the ecological response to long-term climate cycles as evidence grows of intensification of extreme climatic events such as severe drought and heat waves. In this study, we assessed the alleviating effects of artificial flooding on drought impact using the canopy condition of the iconic river red gum forests in Australia's Murray Darling Basin (MDB). To achieve this, we jointly analysed spatial-temporal patterns of NDVI response and drought conditions for the period of 2000-2013, during which the MDB experienced an extreme dry-wet cycle. Our results indicated that while NDVI-derived canopy condition was better at the sites receiving environmental water during the dry phases, both watered and unwatered sites displayed great similarity in seasonality and trends. Furthermore, we did not find any significant difference in NDVI response of the canopy between the sites to suggest significant differences in ecosystem stability and resilience, with watered and unwatered sites showing similar responses to the extreme wet conditions as the drought broke. The highly significant relationship between long-term drought index and NDVI anomaly suggest that climate phase is the main forcing driving canopy condition in semi-arid floodplain forests. PMID:26027753

  3. Climate change impact on North Sea wave conditions: a consistent analysis of ten projections

    NASA Astrophysics Data System (ADS)

    Grabemann, Iris; Groll, Nikolaus; Möller, Jens; Weisse, Ralf

    2015-02-01

    Long-term changes in the mean and extreme wind wave conditions as they may occur in the course of anthropogenic climate change can influence and endanger human coastal and offshore activities. A set of ten wave climate projections derived from time slice and transient simulations of future conditions is analyzed to estimate the possible impact of anthropogenic climate change on mean and extreme wave conditions in the North Sea. This set includes different combinations of IPCC SRES emission scenarios (A2, B2, A1B, and B1), global and regional models, and initial states. A consistent approach is used to provide a more robust assessment of expected changes and uncertainties. While the spatial patterns and the magnitude of the climate change signals vary, some robust features among the ten projections emerge: mean and severe wave heights tend to increase in the eastern parts of the North Sea towards the end of the twenty-first century in nine to ten projections, but the magnitude of the increase in extreme waves varies in the order of decimeters between these projections. For the western parts of the North Sea more than half of the projections suggest a decrease in mean and extreme wave heights. Comparing the different sources of uncertainties due to models, scenarios, and initial conditions, it can be inferred that the influence of the emission scenario on the climate change signal seems to be less important. Furthermore, the transient projections show strong multi-decadal fluctuations, and changes towards the end of the twenty-first century might partly be associated with internal variability rather than with systematic changes.

  4. Impacts of Autonomous Adaptations on the Hydrological Drought Under Climate Change Condition

    NASA Astrophysics Data System (ADS)

    Oki, T.; Satoh, Y.; Pokhrel, Y. N.; KIM, H.; Yoshimura, K.

    2014-12-01

    Because of expected effects of climate changes on quantity and spatial distribution of available water resources, assessment of the changes in the balance between the demand and supply of water resources is critical for some regions. Historically, water deficiencies were overcome by planned water management such as dam regulation and irrigation. But only few studies have investigated the effect of anthropogenic factors on the risk of imbalance of water demand and supply under climate change conditions. Therefore, estimation of the potential deficiency in existing infrastructures under water-environment change is needed to support our society to adapt against future climate changes. This study aims to estimate the impacts of climate changes on the risk of water scarcity projected based on CMIP5 RCP scenarios and the efficiency of autonomous adaptation by anthropogenic water management, such as reservoir operation and irrigation using ground water. First, tendencies of the changes in water scarcity under climate change are estimated by an improved land surface model, which integrates natural water cycles and human activities. Second, the efficiencies of human-developed infrastructure are analyzed by comparing the naturalized and fully anthropogenic offline simulations. It was found that number of hydrological drought days will be increased and decreased in approximately 70 % and 24 % of global land, respectively, considering anthropogenic water management, however, they are approximately 82 % and 16 %, respectively, under naturalized condition without anthropogenic water management. The differences indicate how autonomous adaptation through anthropogenic water management can reduce the impacts of climate change. Also, adequate enhancement of infrastructure is necessary against expected water scarcity under climate change because such positive and negative effects of artificial water regulation show comparable impact on water scarcity risk to that of climate change in

  5. Stability Behaviour of the Atlantic Thermohaline Circulation Under Different Climate Conditions: The Thermal Component

    NASA Astrophysics Data System (ADS)

    Knorr, G.; Eichinger, R.; Lohmann, G.; Prange, M.; Barker, S.

    2010-05-01

    During the Last Glacial Maximum the Atlantic Thermohaline Circulation (THC) was characterized by a southward shift of the North Atlantic deep water (NADW) formation sites and a relatively shallow NADW- overturning cell, compared to the present mode of operation. Furthermore, abrupt climate events during the last glacial are associated with rapid changes in the THC and accompanying changes of the inter-hemispheric northward oceanic heat transport. Using an interhemispheric box model of the Atlantic THC, coupled to a moist energy balance model of the atmosphere we present a new approach, which is based on the assumption that a completely sea ice covered North Atlantic would inhibit the generation of deep water. Therefore we introduce a dependence of the overturning strength from the sea ice extent in the North Atlantic. This approach can be viewed as a loss of efficiency of the inter-hemispheric density gradient in driving the overturning with cooler climate conditions. The transition from the present day climate to a colder climate forces the Atlantic THC to collapse in an intermediate climate state. This change in the stability behaviour is a consequence of the model response to gradual changes in the outgoing infra-red radiation at the top of the atmosphere. At cooler climate states the increasing atmosphere-ocean temperature contrast and associated ocean heat loss dominates the insulating effect of sea ice on North Atlantic temperature and promotes a sea ice growth. This effect is amplified by a weaker overturning circulation and decreased northward oceanic heat transport, which leads to a positive feedback loop and the existence of multiple equilibria in an intermediate climate state. Based on the reduction of the system to key variables governing the stability, we will also discuss the internal and structural stability of the system with the aid of numerical and analytical solutions to gain a deeper understanding of the underlying dynamics. A comparison with

  6. Water supply patterns in two agricultural areas of Central Germany under climate change conditions

    NASA Astrophysics Data System (ADS)

    Tölle, M. H.; Moseley, C.; Panferov, O.; Busch, G.; Knohl, A.

    2012-04-01

    Increasing emissions of greenhouse gases and increasing prices for fossil fuels have highlighted the demand for CO2 "neutral" renewable energy sources, e.g. short rotation forestry systems used for bioenergy. These systems might be vulnerable to changes in temperature, precipitation and occurrence of extreme weather events. To estimate success or failure of such short rotation coppices in a certain area we need regional climate projections and risk assessment. Changes of water supply patterns in two agriculturally extensively used regions in Central Germany (around Göttingen and Großfahner) with different climate conditions but both in the temperate climate zone are explored. The study is carried out under present conditions as well as under projected climate change conditions (1971-2100) using A1B and B1 climate scenarios downscaled for Europe. Analysis of precipitation bias shows regional differences: a strong bias in Göttingen area and a weaker bias in the Großfahner area. A bias correction approach, Quantile mapping, is applied to the ensemble results for both areas for winter and summer seasons. By using quantile regression on the seasonal Standardized Precipitation Indices (SPIs) as indicator for water supply conditions we found that precipitation is expected to increase in winter in all quantiles of the distribution for Göttingen area during the 21th century. Heavy precipitation is also expected to increase for Großfahner area suggesting a trend to wetter extremes in winter for the future. This winter precipitation increase could trigger runoff and soil erosion risk enhancing the severity of floods. Increasing winter availability of water could enhance local water supply in spring. For both areas no significant change in summer was found over the whole time period. Although the climate change signal of the SPI indicate mild dryer conditions in summer at the end of the 21st century which may trigger water shortage and summer drying associated with above

  7. Modelling flood damages under climate change conditions - a case study for Germany

    NASA Astrophysics Data System (ADS)

    Hattermann, F. F.; Huang, S.; Burghoff, O.; Willems, W.; Österle, H.; Büchner, M.; Kundzewicz, Z.

    2014-12-01

    The aim of the study is to analyze and discuss possible climate change impacts on flood damages in Germany. The study was initiated and supported by the German insurance sector whereby the main goal was to identify general climate-related trends in flood hazard and damages and to explore sensitivity of results to climate scenario uncertainty. The study makes use of climate scenarios regionalized for the main river basins in Germany. A hydrological model (SWIM) that had been calibrated and validated for the main river gauges, was applied to transform these scenarios into discharge for more than 5000 river reaches. Extreme value distribution has been fitted to the time series of river discharge to derive the flood frequency statistics. The hydrological results for each river reach have been linked using the flood statistics to related damage functions provided by the German Insurance Association, considering damages on buildings and small enterprises. The result is that, under the specific scenario conditions, a considerable increase in flood related losses can be expected in Germany in future, warmer, climate.

  8. Sensitivity of ICTP Regional Climate Model (RegCM3) to Initial and Lateral Boundary Conditions

    NASA Astrophysics Data System (ADS)

    Nadeem, I.; Formayer, H.

    2009-04-01

    Regional climate simulations require lateral boundary conditions. These are typically reanalysis of past observations or alternatively, output from climate general circulation models. Lateral boundary conditions are available at various temporal and spatial resolutions. At present, spatial resolution of reanalysis datasets ranges from few kilometers, for example, regional reanalysis limited to only single continent, to the coarser but global datasets like ECMWF 40 Years Re-Analysis. While these datasets represent reasonable analyses of 3-D atmospheric as well as surface conditions, their resolutions, the physics of the models used to generate them, and the means of assimilating data into them can produce very different results when used as boundary conditions for regional climate models. The sensitivity of ICTP Regional Climate Model (RegCM3) to different lateral boundary conditions was investigated over the Alpine region. The model was run directly at 10km horizontal resolution as well as in one-way double nested mode, with a 30 km grid point spacing mother domain encompassing the Europe and a 10 km grid point spacing nested domain covering the Alpine Region. The simulations spans the one-year period of 1989. The boundary conditions used for various simulations were ECMWF Interim Re-Analysis (ERA-Interim, 0.75° and 1.5° grid spacings, 6-h intervals), the ECMWF 40 Years Re-Analysis (ERA40, 1° and 2.5° grid spacings, 6-h interval) and finally the 2.5°, 6-h NCEP/DOE AMIP-II Reanalysis (Reanalysis-2). Sea Surface Temperature for the simulated periods were obtained from a UK Met Office Global Ocean Surface Temperature (GISST), a set of SST data in monthly 1° area grids. When recently released ERA-Interim Reanalysis, which is based on a recent release of the Integrated Forecasting System (IFS Cy31r2) containing many improvements both in the forecasting model and analysis methodology, was used as lateral and boundary conditions, the simulated precipitation field

  9. Why were Past North Atlantic Warming Conditions Associated with Drier Climate in the Western United States?

    NASA Astrophysics Data System (ADS)

    Wong, C. I.; Potter, G. L.; Montanez, I. P.; Otto-Bliesner, B. L.; Behling, P.; Oster, J. L.

    2014-12-01

    Investigating climate dynamics governing rainfall over the western US during past warmings and coolings of the last glacial and deglaciation is pertinent to understanding how precipitation patterns might change with future global warming, especially as the processes driving the global hydrological reorganization affecting this drought-prone region during these rapid temperature changes remain unresolved. We present model climates of the Bølling warm event (14,500 years ago) and Younger Dryas cool event (12,200 years ago) that i) uniquely enable the assessment of dueling hypothesis about the atmospheric teleconnections responsible for abrupt temperature shifts in the North Atlantic region to variations in moisture conditions across the western US, and ii) show that existing hypotheses about these teleconnections are unsupported. Modeling results show no evidence for a north-south shift of the Pacific winter storm track, and we argue that a tropical moisture source with evolving trajectory cannot explain alternation between wet/dry conditions, which have been reconstructed from the proxy record. Alternatively, model results support a new hypothesis that variations in the intensity of the winter storm track, corresponding to its expansion/contraction, can account for regional moisture differences between warm and cool intervals of the last deglaciation. Furthermore, we demonstrate that the mechanism forcing the teleconnection between the North Atlantic and western US is the same across different boundary conditions. In our simulation, during the last deglaciation, and in simulations of future warming, perturbation of the Rossby wave structure reconfigures the atmospheric state. This reconfiguration affects the Aleutian Low and high-pressure ridge over and off of the northern North American coastline driving variability in the storm track. Similarity between the processes governing the climate response during these distinct time intervals illustrates the robust nature

  10. Hydrological response to changing climate conditions: Spatial streamflow variability in the boreal region

    NASA Astrophysics Data System (ADS)

    Teutschbein, C.; Grabs, T.; Karlsen, R. H.; Laudon, H.; Bishop, K.

    2015-12-01

    In this paper we combined a multimodel ensemble based on 15 regional climate models with a multicatchment approach to explore the hydrologic sensitivity of 14 neighboring and rather similar catchments to changing climate conditions. Current (1982-2010) and future (2062-2090) streamflow was simulated with the HBV model. A diagnostic approach was used, which considered major behavioral catchment functions by using hydrologically relevant signatures related to overall water balance, flow duration curves and hydrograph attributes. Projected increases in temperature and precipitation resulted in increased total available streamflow, with lower spring and summer flows, but substantially higher winter streamflow. Furthermore, significant changes in flow durations with lower chances of both high and low flows can be expected in boreal Sweden in the future. This overall trend in projected streamflow pattern changes was comparable among the analyzed catchments but the magnitude of change differed considerably. This suggests that catchments belonging to the same region can show distinctly different degrees of hydrological responses to the same external climate change signal. We reason that differences in spatially distributed physical catchment properties within catchments are not only of great importance for current streamflow behavior, but also play a major role in the sensitivity of catchments to changing climate conditions.

  11. North Sea wave conditions: an analysis of four transient future climate realizations

    NASA Astrophysics Data System (ADS)

    Groll, Nikolaus; Grabemann, Iris; Gaslikova, Lidia

    2014-01-01

    The multi-decadal wave conditions in the North Sea can be influenced by anthropogenic climate change. That may lead to the intensification of wave extremes in the future and consequently increase risks for the coastal areas as well as for on- and offshore human activities. Potential changes caused by alteration of atmospheric patterns are investigated. Four transient climate projections (1961-2100), reflecting two IPCC emission scenarios (A1B and B1) and two different initial states, are used to simulate the wave scenarios. The potential wind-induced changes in waves are studied by comparing future statistics (2001-2100) with the corresponding reference conditions (1961-2000). Generally, there is a small increase in future 99th percentile significant wave height for most eastern parts of the North Sea towards the end of the twenty-first century. This small increase is superimposed by a strong variability of the annual extremes on time scales of decades. Opposite to the differences in wave height, the change in wave direction to more waves propagating east shows less decadal variability and is more uniform among all realizations. Nevertheless, temporal and spatial differences of the wave height in the four climate projections point to the uncertainties in the climate change signals.

  12. Regression tree modeling of forest NPP using site conditions and climate variables across eastern USA

    NASA Astrophysics Data System (ADS)

    Kwon, Y.

    2013-12-01

    As evidence of global warming continue to increase, being able to predict forest response to climate changes, such as expected rise of temperature and precipitation, will be vital for maintaining the sustainability and productivity of forests. To map forest species redistribution by climate change scenario has been successful, however, most species redistribution maps lack mechanistic understanding to explain why trees grow under the novel conditions of chaining climate. Distributional map is only capable of predicting under the equilibrium assumption that the communities would exist following a prolonged period under the new climate. In this context, forest NPP as a surrogate for growth rate, the most important facet that determines stand dynamics, can lead to valid prediction on the transition stage to new vegetation-climate equilibrium as it represents changes in structure of forest reflecting site conditions and climate factors. The objective of this study is to develop forest growth map using regression tree analysis by extracting large-scale non-linear structures from both field-based FIA and remotely sensed MODIS data set. The major issue addressed in this approach is non-linear spatial patterns of forest attributes. Forest inventory data showed complex spatial patterns that reflect environmental states and processes that originate at different spatial scales. At broad scales, non-linear spatial trends in forest attributes and mixture of continuous and discrete types of environmental variables make traditional statistical (multivariate regression) and geostatistical (kriging) models inefficient. It calls into question some traditional underlying assumptions of spatial trends that uncritically accepted in forest data. To solve the controversy surrounding the suitability of forest data, regression tree analysis are performed using Software See5 and Cubist. Four publicly available data sets were obtained: First, field-based Forest Inventory and Analysis (USDA

  13. [Tropical climate pathology].

    PubMed

    Besancenot, J P

    1997-01-01

    In addition to being a determinant factor for the development of infectious and parasitic diseases, tropical weather conditions can have harmful effects for the human organism different from those of temperate climates. Adverse effects can result from aggressive environmental factors such as ultraviolet radiation, extreme heat, abrupt changes in temperature, and tropical storms. In weather-sensitive subjects, exposure to tropical conditions increases the risk of acute reactions including ischemic heart disease, asthma attacks, and kidney stones. Adverse effects can be enhanced by suddenness of change in climate as underlined by the stress experienced by air travelers. In practice it is important to recognize that different tropical climates have different effects on health. Intertropical climates range from dry and rainy areas to plains and mountain areas. Knowledge of the concepts of climatopathology is necessary to advise patients on the choice of destination and the most favorable period for travel. PMID:9612744

  14. Multidecadal changes in moisture condition during climatic growing period of crops in Northeast China

    NASA Astrophysics Data System (ADS)

    Zhao, Junfang; Guo, Jianping

    Investigating the spatiotemporal dynamics of agricultural water status during crop growth season can provide scientific evidences for more efficient use of water resources and sustainable development of agricultural production under climate change. In this study, the following were used to evaluate the multidecadal changes in moisture condition during climatic growth period of crops in Northeast China from 1961 to 2010: (1) the daily climate variables gathered from 101 meteorological stations in Northeast China for 1961-2010; (2) FAO (Food and Agriculture Organization) Penman-Monteith equation; (3) 80% guaranteed probability for agro-climatic indicators; and (4) the daily average temperature stably passing 0 °C, which is the threshold temperature of climatic growth period for crops. Reference crop evapotranspiration (ET0) and relative moisture index were further calculated. The results showed that Northeast China's climate in the main agricultural areas over the past 50 years was warmer and drier in general, with a growing range and intensity of drought. From 1961 to 2010, when the daily average temperature stably passed 0 °C, the average annual total precipitation (P) and ET0 with 80% guaranteed probability in Northeast China both emerged as decreasing trends with averages of 555.0 mm and 993.7 mm, respectively. However, the decline in P was greater than that of annual total ET0. As a result, the annual relative moisture indices sharply decreased with an average of -0.44, mostly fluctuating from -0.59 to -0.25. As far as spatial distributions were concerned, the inter-regional reductions in P and relative moisture index over the past 50 years were conspicuous, especially in some agricultural areas of central Heilongjiang Province, northeastern Jilin Province and northeastern Liaoning Province. On the contrary, ET0 obviously increased in some agricultural areas of central and northwestern Heilongjiang Province (eg. Qiqiha'er, Shuangyashan, Hegang, Suihua, etc

  15. Is bias correction of Regional Climate Model (RCM) simulations possible for non-stationary conditions?

    NASA Astrophysics Data System (ADS)

    Teutschbein, Claudia; Seibert, Jan

    2014-05-01

    Regional Climate Models (RCMs) are commonly used in climate-change impact studies to transfer large-scale Global Climate Model (GCM) values to smaller scales and to provide more detailed regional information. There is, however, the problem that RCM simulations often show considerable deviations from local observations due to systematic and random model errors. This issue has caused the development of several correction approaches, that can be classified according to their degree of complexity and include simple-to-apply methods such as linear transformations but also more advanced methods such as distribution mapping. Most of these common correction approaches are based on the assumption that RCM errors do not change over time. It is in principle not possible to test whether this underlying assumption of error stationarity is actually fulfilled for future climate conditions. In this contribution, however, we show that it is possible to evaluate how well correction methods perform for conditions different from those that they were calibrated to. This can be done with the relatively simple differential split-sample test, originally proposed by Klemeš ["Operational testing of hydrological simulation models", Hydrological Sciences Journal 31, no. 1 (1986): 13-24]. For five Swedish catchments, precipitation and temperature time series from 15 different ERA40-driven RCM simulations were corrected with different commonly-used bias correction methods. We then performed differential split-sample tests by dividing the data series into cold and warm respective dry and wet years. This enabled us to cross-evaluate the performance of different correction procedures under systematically varying climate conditions. The differential split-sample test identified major differences in the ability of the applied correction methods to reduce model errors and to cope with non-stationary biases. More advanced correction methods performed better, whereas large deviations remained for

  16. Comparison of winter wheat yield sensitivity to climate variables under irrigated and rain-fed conditions

    NASA Astrophysics Data System (ADS)

    Xiao, Dengpan; Shen, Yanjun; Zhang, He; Moiwo, Juana P.; Qi, Yongqing; Wang, Rende; Pei, Hongwei; Zhang, Yucui; Shen, Huitao

    2016-09-01

    Crop simulation models provide alternative, less time-consuming, and cost-effective means of determining the sensitivity of crop yield to climate change. In this study, two dynamic mechanistic models, CERES (Crop Environment Resource Synthesis) and APSIM (Agricultural Production Systems Simulator), were used to simulate the yield of wheat ( Triticum aestivum L.) under well irrigated (CFG) and rain-fed (YY) conditions in relation to different climate variables in the North China Plain (NCP). The study tested winter wheat yield sensitivity to different levels of temperature, radiation, precipitation, and atmospheric carbon dioxide (CO2) concentration under CFG and YY conditions at Luancheng Agro-ecosystem Experimental Stations in the NCP. The results from the CERES and APSIM wheat crop models were largely consistent and suggested that changes in climate variables influenced wheat grain yield in the NCP. There was also significant variation in the sensitivity of winter wheat yield to climate variables under different water (CFG and YY) conditions. While a temperature increase of 2°C was the threshold beyond which temperature negatively influenced wheat yield under CFG, a temperature rise exceeding 1°C decreased winter wheat grain yield under YY. A decrease in solar radiation decreased wheat grain yield under both CFG and YY conditions. Although the sensitivity of winter wheat yield to precipitation was small under the CFG, yield decreased significantly with decreasing precipitation under the rainfed YY treatment. The results also suggest that wheat yield under CFG linearly increased by ≈3.5% per 60 ppm (parts per million) increase in CO2 concentration from 380 to 560 ppm, and yield under YY increased linearly by ≈7.0% for the same increase in CO2 concentration.

  17. Comparison of winter wheat yield sensitivity to climate variables under irrigated and rain-fed conditions

    NASA Astrophysics Data System (ADS)

    Xiao, Dengpan; Shen, Yanjun; Zhang, He; Moiwo, Juana P.; Qi, Yongqing; Wang, Rende; Pei, Hongwei; Zhang, Yucui; Shen, Huitao

    2015-11-01

    Crop simulation models provide alternative, less time-consuming, and cost-effective means of determining the sensitivity of crop yield to climate change. In this study, two dynamic mechanistic models, CERES (Crop Environment Resource Synthesis) and APSIM (Agricultural Production Systems Simulator), were used to simulate the yield of wheat (Triticum aestivum L.) under well irrigated (CFG) and rain-fed (YY) conditions in relation to different climate variables in the North China Plain (NCP). The study tested winter wheat yield sensitivity to different levels of temperature, radiation, precipitation, and atmospheric carbon dioxide (CO2) concentration under CFG and YY conditions at Luancheng Agro-ecosystem Experimental Stations in the NCP. The results from the CERES and APSIM wheat crop models were largely consistent and suggested that changes in climate variables influenced wheat grain yield in the NCP. There was also significant variation in the sensitivity of winter wheat yield to climate variables under different water (CFG and YY) conditions. While a temperature increase of 2°C was the threshold beyond which temperature negatively influenced wheat yield under CFG, a temperature rise exceeding 1°C decreased winter wheat grain yield under YY. A decrease in solar radiation decreased wheat grain yield under both CFG and YY conditions. Although the sensitivity of winter wheat yield to precipitation was small under the CFG, yield decreased significantly with decreasing precipitation under the rainfed YY treatment. The results also suggest that wheat yield under CFG linearly increased by ≈3.5% per 60 ppm (parts per million) increase in CO2 concentration from 380 to 560 ppm, and yield under YY increased linearly by ≈7.0% for the same increase in CO2 concentration.

  18. Estimating the influence of vegetation on net infiltration under future climatic conditions

    NASA Astrophysics Data System (ADS)

    Stothoff, S. A.

    2005-12-01

    Performance assessments of the proposed geologic repository at Yucca Mountain, Nevada, are sensitive to the net infiltration passing the root zone above the repository, an area of roughly 5 km2. The area of interest has a semiarid climate, ten washes in rugged topography, and shallow soils overlying fractured bedrock composed of silicic volcanic tuff. Mean annual net infiltration is uncertain but constrained under current climatic conditions, based on modeling and observations. Performance assessments that consider periods of one or more glacial cycles must address net infiltration under wetter and cooler future climatic conditions. Potential evapotranspiration under current climatic conditions is sufficiently large relative to mean annual precipitation that numerical simulators are relatively insensitive to how evapotranspiration is implemented in the model. Water passes from soil into the bedrock only over short periods while the soil is wet following large storms. Under wetter and cooler climatic conditions, the representation of evapotranspiration may be more important, particularly the component handling plant uptake. Plant uptake models from the crop science literature assume that the plants have a predictable growth pattern over a growing season and predictable rooting patterns. These assumptions, reasonable for agricultural situations with annual crops in deep soil, may be questionable or difficult to parameterize when considering uptake from long-lived shrubs in semiarid climates with shallow soils and strong interannual variation in rainfall. An adaptive vegetation model is proposed that allows vegetation to respond to environmental influences. The adaptive model allocates roots according to uptake, which is mediated by the environment, within limits set by genetic preferences. The model allows growth in wet periods and dieback in dry periods, and allocates roots within the bedrock fractures to the depth supported by moisture availability. Estimated mean

  19. Evaluating global reanalysis datasets for provision of boundary conditions in regional climate modelling

    NASA Astrophysics Data System (ADS)

    Moalafhi, Ditiro B.; Evans, Jason P.; Sharma, Ashish

    2016-01-01

    Regional climate modelling studies often begin by downscaling a reanalysis dataset in order to simulate the observed climate, allowing the investigation of regional climate processes and quantification of the errors associated with the regional model. To date choice of reanalysis to perform such downscaling has been made based either on convenience or on performance of the reanalyses within the regional domain for relevant variables such as near-surface air temperature and precipitation. However, the only information passed from the reanalysis to the regional model are the atmospheric temperature, moisture and winds at the location of the boundaries of the regional domain. Here we present a methodology to evaluate reanalyses derived lateral boundary conditions for an example domain over southern Africa using satellite data. This study focusses on atmospheric temperature and moisture which are easily available. Five commonly used global reanalyses (NCEP1, NCEP2, ERA-I, 20CRv2, and MERRA) are evaluated against the Atmospheric Infrared Sounder satellite temperature and relative humidity over boundaries of two domains centred on southern Africa for the years 2003-2012 inclusive. The study reveals that MERRA is the most suitable for climate mean with NCEP1 the next most suitable. For climate variability, ERA-I is the best followed by MERRA. Overall, MERRA is preferred for generating lateral boundary conditions for this domain, followed by ERA-I. While a "better" LBC specification is not the sole precursor to an improved downscaling outcome, any reduction in uncertainty associated with the specification of LBCs is a step in the right direction.

  20. Morpho-physiological features of human populations in the context of climatic--geographical conditions.

    PubMed

    Belkin, Victor; Korostishevsky, Michael; Batsevich, Valery; Pavlovsky, Oleg; Volkov-Dubrovin, Vladimir; Kobyliansky, Eugene

    2012-09-01

    This paper is based on the data obtained in the course of population studies conducted in 33 geographical regions of the former USSR territory by the faculty of the Anuchin Research Institute and Museum of Anthropology, Lomonosov Moscow State University, between 1961 and 1991. The data resulting from study of 4386 male and 4626 female subjects aged 17 to 99 include head and body morphology, bone mineral density, blood oxygen saturation and blood biochemistry. We aimed at studying the link between the traits of a population and the climatic conditions of the area inhabited by this population. Individual characteristics of the subjects were normalized by age and sex, and factor analysis was used to reduce the number of cross-correlating features. As a result, several integral characteristics (factors) were identified: five body morphology-related factors, two head morphology-related factors, one bone mineral density-related factor, one blood oxygen saturation-related factor and three blood biochemistry-related factors. These factors explained 79.3%, 78.38%, 63.51%, 74.4% and 66.77% of the trait groups' variability, respectively. The correlation analysis between these factors and climatic indicators demonstrated that chest dimensions were the least tolerant to the climatic conditions among the morphological characteristics studied. Hemoglobin-protein ratios, as well as the factor that includes total cholesterol, were the most climate-dependent among the biochemical parameters. As far as our data show, blood serum oxygen saturation--the key factor determining the performance of the cardiovascular and respiratory systems--is also climate-dependent. PMID:23213926

  1. Development of streamflow projections under changing climate conditions over Colorado River basin headwaters

    NASA Astrophysics Data System (ADS)

    Miller, W. P.; Piechota, T. C.; Gangopadhyay, S.; Pruitt, T.

    2011-07-01

    The current drought over the Colorado River Basin has raised concerns that the US Department of the Interior, Bureau of Reclamation (Reclamation) may impose water shortages over the lower portion of the basin for the first time in history. The guidelines that determine levels of shortage are affected by relatively short-term (3 to 7 month) forecasts determined by the Colorado Basin River Forecast Center (CBRFC) using the National Weather Service (NWS) River Forecasting System (RFS) hydrologic model. While these forecasts by the CBRFC are useful, water managers within the basin are interested in long-term projections of streamflow, particularly under changing climate conditions. In this study, a bias-corrected, statistically downscaled dataset of projected climate is used to force the NWS RFS utilized by the CBRFC to derive projections of streamflow over the Green, Gunnison, and San Juan River headwater basins located within the Colorado River Basin. This study evaluates the impact of changing climate to evapotranspiration rates and contributes to a better understanding of how hydrologic processes change under varying climate conditions. The impact to evapotranspiration rates is taken into consideration and incorporated into the development of streamflow projections over Colorado River headwater basins in this study. Additionally, the NWS RFS is modified to account for impacts to evapotranspiration due to changing temperature over the basin. Adjusting evapotranspiration demands resulted in a 6 % to 13 % average decrease in runoff over the Gunnison River Basin when compared to static evapotranspiration rates. Streamflow projections derived using projections of future climate and the NWS RFS provided by the CBRFC resulted in decreased runoff in 2 of the 3 basins considered. Over the Gunnison and San Juan River basins, a 10 % to 15 % average decrease in basin runoff is projected through the year 2099. However, over the Green River basin, a 5 % to 8 % increase in basin

  2. Durability of the Indian Kandla Grey sandstone under Western European climatic conditions.

    NASA Astrophysics Data System (ADS)

    Boever, W.; Cnudde, V.; Dewanckele, J.; De Kock, T.; Boone, M.; Boone, M. N.; Silversmit, G.; Van Ranst, E.; Derluyn, H.; Peetermans, S.; Hovind, J.; Modregger, P.; Stampanoni, M.; De Buysser, K.; De Schutter, G.

    2012-04-01

    An increasing amount of imported natural building stones are being used in Western Europe, often as a replacement of more traditional, local building stones. Unlike for these traditional stones, which have been used under the prevailing climatic conditions in Western Europe, the durability of these imported stones is largely unknown. Therefore, it is essential to study their behaviour under these climatic conditions in order to predict their weathering resistance. Thus, the chemical and structural properties of these new building materials need to be determined and their behaviour under changing environmental conditions needs to be studied. When these materials are being used in Western Europe, they have to resist to significant mechanical stresses due to the imbibition of de-icing salt solutions. These de-icing salts are very frequently used during winter in Western Europe, while temperature fluctuates between freezing and thaw conditions. In this research, focus has been laid on the multi-disciplinary characterization of the compact Kandla Grey layered sandstone. This stone is recently frequently imported from India to Belgium. Besides traditional techniques, (according to European Standards for natural stone testing) highly advanced research techniques such as neutron and X-ray imaging (at synchrotron and in laboratory) and µ-XRF were used to characterize and monitor the changes under different external conditions such as freezing, thawing and salt crystallization. The results of this study demonstrate that the structural properties of the laminations inside Kandla Grey have an influence on the resistance of the stone to frost and salt weathering. Based on these results, it can be concluded that Kandla Grey can be vulnerable to these types of weathering under the current climatic conditions in Western Europe.

  3. Comparing the Slaking of Clay-Bearing Rocks Under Laboratory Conditions to Slaking Under Natural Climatic Conditions

    NASA Astrophysics Data System (ADS)

    Gautam, T. P.; Shakoor, A.

    2016-01-01

    The objective of this study was to compare the laboratory slaking behavior of common clay-bearing rocks to their slaking behavior under natural climatic conditions observed during a 1-year experimental study. Five-cycle slake durability tests were performed in the laboratory on five claystones, five mudstones, five siltstones, and five shales. Twelve replicate specimens of each of these 20 rocks were also exposed to natural climatic conditions for 12 months. After each month of exposure, one replicate specimen of each rock was removed from natural exposure and its grain size distribution was determined. The results of laboratory tests and field experiment were compared in terms of 1st, 2nd, 3rd, 4th, and 5th cycle slake durability indices (Id1, Id2, Id3, Id4, Id5), grain size distribution of slaked material, and disintegration ratio ( D R), where D R is the ratio of the area under the grain size distribution curve of slaked material for a given specimen to the total area encompassing all grain size distribution curves of the specimens tested. Correlations of Id1, Id2, Id3, Id4, and Id5 with D R values for laboratory specimens exhibit R 2 values of 0.87, 0.88, 0.83, 0.75, and 0.70, respectively. However, the relationship between Id2 and D R, determined after 1, 3, 6, and 12 months of natural exposure, becomes weaker with increasing time of exposure, with R 2 values of 0.65, 0.63, 0.63, and 0.25, respectively. The fifth-cycle slake durability index (Id5) for laboratory tested specimens shows a better correlation with D R values for naturally exposed specimens ( R 2 up to 0.80). A comparison of grain size distribution curves of slaked material for laboratory specimens, after the 2nd cycle slake durability test, with those of specimens exposed to natural climatic conditions shows that the laboratory test underestimates the field durability for claystones, and overestimates it for siltstones.

  4. Precipitation-climate sensitivity to initial conditions in an atmospheric general circulation model

    SciTech Connect

    Covey, C., LLNL

    1997-03-01

    Atmospheric climate, in contrast to weather, is traditionally considered to be determined by boundary conditions such as sea surface temperature (SST). To test this hypothesis, we examined annual mean precipitation from an ensemble of 20 general circulation model (GCM) simulations. Ensemble members were forced with identical 10-year series of SST and sea ice, but they began with slightly differing initial conditions. A surprisingly small proportion of the variance in the output is attributable to the effects of boundary forcing. This result-and similar evidence from smaller ensembles of other GCM simulations-implies that long-term precipitation variations are mostly unpredictable, even if SST forecasts are `perfect.`

  5. Impact of regional afforestation on climatic conditions in metropolitan areas: case study of Copenhagen

    NASA Astrophysics Data System (ADS)

    Stysiak, Aleksander Andrzej; Bergen Jensen, Marina; Mahura, Alexander

    2016-04-01

    Like most other places, European metropolitan areas will face a range of climate-related challenges over the next decades that may influence the nature of urban life across the continent. Under future urbanization and climate change scenarios the well-being and comfort of the urban population might become progressively compromised. In urban areas, the effects of the warming climate will be accelerated by combination of Urban Heat Island effect (UHI) and extreme heat waves. The land cover composition directly influences atmospheric variability, and can either escalate or downscale the projected changes. Vegetation, forest ecosystems in particular, are anticipated to play an important role in modulating local and regional climatic conditions, and to be vital factor in the process of adapting cities to warming climate. This study investigates the impact of forest and land-cover change on formation and development of temperature regimes in the Copenhagen Metropolitan Area (CPH-MA). Potential to modify the UHI effect in CPH-MA is estimated. Using 2009 meteorological data, and up-to-date 2012 high resolution land-cover data we employed the online integrated meteorology-chemistry/aerosols Enviro-HIRLAM (Environment - High Resolution Limited Area Model) modeling system to simulate air temperature (at 2 meter height) fields for a selected period in July 2009. Employing research tools (such as METGRAF meteorological software and Geographical Information Systems) we then estimated the influence of different afforestation and urbanization scenarios with new forests being located after the Danish national afforestation plan, after proximity to the city center, after dominating wind characteristics, and urbanization taking place as densification of the existing conurbation. This study showed the difference in temperature up to 3.25°C, and the decrease in the spatial extent of temperature fields up to 68%, depending on the selected scenario. Performed simulations demonstrated

  6. Uncertainties in Predicting Rice Yield by Current Crop Models Under a Wide Range of Climatic Conditions

    NASA Technical Reports Server (NTRS)

    Li, Tao; Hasegawa, Toshihiro; Yin, Xinyou; Zhu, Yan; Boote, Kenneth; Adam, Myriam; Bregaglio, Simone; Buis, Samuel; Confalonieri, Roberto; Fumoto, Tamon; Gaydon, Donald; Marcaida, Manuel, III; Nakagawa, Hiroshi; Oriol, Philippe; Ruane, Alex C.; Ruget, Francoise; Singh, Balwinder; Singh, Upendra; Tang, Liang; Tao, Fulu; Wilkens, Paul; Yoshida, Hiroe; Zhang, Zhao; Bouman, Bas

    2014-01-01

    Predicting rice (Oryza sativa) productivity under future climates is important for global food security. Ecophysiological crop models in combination with climate model outputs are commonly used in yield prediction, but uncertainties associated with crop models remain largely unquantified. We evaluated 13 rice models against multi-year experimental yield data at four sites with diverse climatic conditions in Asia and examined whether different modeling approaches on major physiological processes attribute to the uncertainties of prediction to field measured yields and to the uncertainties of sensitivity to changes in temperature and CO2 concentration [CO2]. We also examined whether a use of an ensemble of crop models can reduce the uncertainties. Individual models did not consistently reproduce both experimental and regional yields well, and uncertainty was larger at the warmest and coolest sites. The variation in yield projections was larger among crop models than variation resulting from 16 global climate model-based scenarios. However, the mean of predictions of all crop models reproduced experimental data, with an uncertainty of less than 10 percent of measured yields. Using an ensemble of eight models calibrated only for phenology or five models calibrated in detail resulted in the uncertainty equivalent to that of the measured yield in well-controlled agronomic field experiments. Sensitivity analysis indicates the necessity to improve the accuracy in predicting both biomass and harvest index in response to increasing [CO2] and temperature.

  7. Nitrogen partitioning in oak leaves depends on species, provenance, climate conditions and soil type.

    PubMed

    Hu, B; Simon, J; Kuster, T M; Arend, M; Siegwolf, R; Rennenberg, H

    2013-01-01

    Climate-tolerant tree species and/or provenances have to be selected to ensure the high productivity of managed forests in Central Europe under the prognosticated climate changes. For this purpose, we studied the responses of saplings from three oak species (i.e. Quercus robur, Q. petraea and Q. pubescens) and provenances of different climatic origin (i.e. low or high rainfall, low or high temperature habitats) with regard to leaf nitrogen (N) composition as a measure of N nutrition. Saplings were grown in model ecosystems on either calcareous or acidic soil and subjected to one of four treatments (control, drought, air warming or a combination of drought and air warming). Across species, oak N metabolism responded to the influence of drought and/or air warming with an increase in leaf amino acid N concentration at the expense of structural N. Moreover, provenances or species from drier habitats were more tolerant to the climate conditions applied, as indicated by an increase in amino acid N (comparing species) or soluble protein N (comparing provenances within a species). Furthermore, amino acid N concentrations of oak leaves were significantly higher on calcareous compared to acidic soil. From these results, it can be concluded that seeds from provenances or species originating from drier habitats and - if available - from calcareous soil types may provide a superior seed source for future forest establishment. PMID:22934888

  8. Conditioning of Flow Projections under Climate Change on Hydrologic Signatures within the GLUE Framework

    NASA Astrophysics Data System (ADS)

    Todorovic, Andrijana; Plavsic, Jasna; Despotovic, Jovan

    2016-04-01

    Climate change impact on water resources is generally quantified in terms of relative changes in characteristic flows (e.g. annual runoff, median annual flows, etc.) over a future period compared to the baseline one. These changes are estimated under the assumed emission scenarios and with one or more modelling chains (combinations of the Global and Regional Climate Models, and a hydrological model). Since different modelling chains yield different projections, estimates of these relative changes are uncertain. High prediction uncertainty is reflected in a wide 90 per cent prediction uncertainty band (90PPU) or in a distribution that resembles the uniform distribution. Therefore, research in robustness of the modelling chains has been conducted. The goal of the research is to appoint higher probabilities to the projections obtained by the more robust chains, and in that way reduce the uncertainty in flow projections under climate change. In this research, the hydrologic projections are conditioned on the hydrologic signatures within the GLUE framework. Namely, a relative change obtained with a modelling chain is assigned a likelihood depending on the performance of the chain in terms of the hydrologic signatures over the baseline period. High flow projections (2nd percentile of the daily flows) are conditioned on the high-segment of the flow duration curve (FDC), projections of the median flows are conditioned on the FDC mid-segment slope, and the projections of the low flows are conditioned on the FDC low-segment. The projections of total annual runoff are conditioned on the entire FDC. The likelihoods are quantified in terms of Nash-Sutcliffe efficiency coefficient (NSE) evaluated from the FDCs of the flows simulated by the modelling chains and the observed FDC. The methodology presented is applied to develop flow projections in the Kolubara River catchment in Serbia over the mid 21st century (2041-2070). Hydrologic projections are obtained by the HBV

  9. Impact of bias correction method on simulated runoff conditions under a large ensemble of climate change scenarios

    NASA Astrophysics Data System (ADS)

    Kling, Harald; Klein, Bastian; Stanzel, Philipp

    2013-04-01

    A common approach for assessing future runoff conditions is to drive hydrological models with downscaled, bias corrected data of climate models. In a previous study for the Upper Danube basin, Kling et al. (2012) used a large ensemble of regional climate models to analyse the uncertainty in future runoff projections due to choice of climate model. In this follow-up study we extend this work by also examining the impact of the bias correction method. We apply five different bias correction methods to monthly precipitation and temperature data of 32 recently published regional climate models of the ENSEMBLES and CERA climate data bases. The bias correction methods include delta change, linear scaling, moment scaling, quantile mapping and a de-trended version of quantile mapping. This yields 160 different climate scenario sets for runoff modelling until the end of the 21st century, showing distinctive changes in mean annual runoff, seasonality in runoff, distribution of runoff and low flows of the Danube River. In general the uncertainty due to choice of climate model is considerably larger than due to choice of bias correction method. Only for climate models that perform exceptionally poor for simulation of historic climate, the choice of bias correction method becomes similarly important for future runoff simulations. Systematic differences - albeit smaller than between climate models - are found between two groups of bias correction methods. The climate change signals differ between these two groups after application of the bias correction. A detailed analysis of climate model error properties reveals for most climate models a problematic cross-correlation between projected trends in future climate and errors in historic climate variability. Thereby, the climate change signals in future mean annual temperature and precipitation are modified in frequency-based bias correction methods, such as the popular quantile mapping method. As there is no way of quantifying the

  10. Simulating runoff under changing climatic conditions: Revisiting an apparent deficiency of conceptual rainfall-runoff models

    NASA Astrophysics Data System (ADS)

    Fowler, Keirnan J. A.; Peel, Murray C.; Western, Andrew W.; Zhang, Lu; Peterson, Tim J.

    2016-03-01

    Hydrologic models have potential to be useful tools in planning for future climate variability. However, recent literature suggests that the current generation of conceptual rainfall runoff models tend to underestimate the sensitivity of runoff to a given change in rainfall, leading to poor performance when evaluated over multiyear droughts. This research revisited this conclusion, investigating whether the observed poor performance could be due to insufficient model calibration and evaluation techniques. We applied an approach based on Pareto optimality to explore trade-offs between model performance in different climatic conditions. Five conceptual rainfall runoff model structures were tested in 86 catchments in Australia, for a total of 430 Pareto analyses. The Pareto results were then compared with results from a commonly used model calibration and evaluation method, the Differential Split Sample Test. We found that the latter often missed potentially promising parameter sets within a given model structure, giving a false negative impression of the capabilities of the model. This suggests that models may be more capable under changing climatic conditions than previously thought. Of the 282[347] cases of apparent model failure under the split sample test using the lower [higher] of two model performance criteria trialed, 155[120] were false negatives. We discuss potential causes of remaining model failures, including the role of data errors. Although the Pareto approach proved useful, our aim was not to suggest an alternative calibration strategy, but to critically assess existing methods of model calibration and evaluation. We recommend caution when interpreting split sample results.

  11. Effects of Simulated Climate Conditions on Phosphorus Cycling in an Annual Grassland Ecosystem

    NASA Astrophysics Data System (ADS)

    Mellett, T.; Paytan, A.; Defforey, D.; Roberts, K.

    2014-12-01

    The Jasper Ridge Global Change Experiment is a long-term study of the effects of simulated climate change conditions on an annual grassland ecosystem. The different treatments consist of elevated atmospheric CO2 levels, enhanced nitrate deposition, as well as higher temperatures and precipitation rates. A representative portion of the above ground vegetation from each plot is harvested. The aim of this study is to investigate the effects of different climate conditions on the phosphorus content and phosphorus cycling in terrestrial plants. Since phosphorus only has one stable isotope, the δ18O signature in phosphate is used as a proxy to investigate phosphorus cycling. Although this technique has been successful in determining phosphorous cycling in aquatic systems, only a few studies have used this approach for terrestrial ecosystems. We analyzed the δ18O of the most abundant grass from each of the plots and treatments. The δ18O values of each sample are compared to elemental budgets of carbon, nitrogen, and phosphorous for correlation as well as soil enzyme activities. and the combination of measures are assessed as indicators for phosphorus limitation in each respective treatment site and provide a better understanding of phosphorus cycling in annual grasslands and the potential effects of climate change on phosphorus cycling.

  12. Effects of Simulated Climate Conditions on Phosphorus Cycling in an Annual Grassland

    NASA Astrophysics Data System (ADS)

    Mellett, T.; Defforey, D.; Paytan, A.

    2012-12-01

    The Jasper Ridge Global Change Experiment is a long-term study of the effects of simulated climate change conditions on an annual grassland. The different treatments consist of elevated atmospheric CO2 levels, enhanced nitrate deposition, as well as higher temperatures and precipitation rates. The above ground vegetation from each plot is harvested and separated by species, with the dominant species being selected for analysis. The aim of this study is to investigate the effects of different climate conditions on the phosphorus content and phosphorus cycling in terrestrial plants. Phosphorus content in grass samples is determined using the colorimetric reaction (soluble reactive phosphorus content), as well as combustion and acid digestion (total phosphorus content). Since phosphorus only has one stable isotope, the δ18O signature in phosphate is used as a proxy to investigate phosphorus cycling in this ecosystem. These three tools will be combined and evaluated as indicators for phosphorus limitation in each respective treatment site and provide a better understanding of phosphorus cycling in annual grasslands and the potential effects of climate change on phosphorus cycling.

  13. Invited review: Influence of climatic conditions on the development, performance, and health of calves.

    PubMed

    Roland, L; Drillich, M; Klein-Jöbstl, D; Iwersen, M

    2016-04-01

    The objective of this review is to provide the reader with an overview of thermoregulatory mechanisms and the influence of climatic conditions in different housing systems on the development, performance, and health of calves. Thermic stress is observed in association with extreme temperatures and large temperature variations, but other variables such as relative humidity and wind speed can also contribute to thermic stress. Thermoregulation in calves is similar to that in adult cattle, but especially dystocial calves are more prone to heat loss. Heat or cold stress results in direct economic losses because of increased calf mortality and morbidity, as well as indirect costs caused by reduced weight gain, performance, and long-term survival. The climatic conditions in a variety of housing systems, associated health problems, and strategies to mitigate thermic stress are discussed in this review. The goal of housing is to alleviate the effect of climate on calves and provide a microclimate. Adequate ventilation with fresh air is essential to reduce respiratory disease. Common practices such as raising calves in individual outdoor enclosures have been challenged lately. Recent research seeks to evaluate the suitability of group housing under practical, economic, and animal welfare considerations. Limited results for reducing thermic stress can be achieved by simple measures such as shades or shelter, but additional heat or cold stress relieving strategies can be required depending on the housing system. PMID:26874416

  14. Plasmid load adversely affects growth and gluconic acid secretion ability of mineral phosphate-solubilizing rhizospheric bacterium Enterobacter asburiae PSI3 under P limited conditions.

    PubMed

    Sharma, Vikas; Archana, G; Naresh Kumar, G

    2011-01-20

    Effect of the metabolic load caused by the presence of plasmids on mineral phosphate-solubilizing (MPS) Enterobacter asburiae PSI3, was monitored with four plasmid cloning vectors and one native plasmid, varying in size, nature of the replicon, copy number and antibiotic resistance genes. Except for one plasmid, the presence of all other plasmids in E. asburiae PSI3 resulted in the loss of the MPS phenotype as reflected by the failure to bring about a drop in pH and release soluble P when grown in media containing rock phosphate (RP) as the sole P source. When 100 μM soluble P was supplemented along with RP, the adverse effects of plasmids on MPS phenotype and on growth parameters was reduced for some plasmid bearing derivatives, as monitored in terms of specific growth rates, glucose consumed, gluconic acids yields and P released. When 10 mM of soluble P as the only P source, was added to the medium all transformants showed growth and pH drop comparable with native strain. It may be concluded that different plasmids impose, to varying extents, a metabolic load in the phosphate-solubilizing bacterium E. asburiae PSI3 and results in diminishing its growth and P-solubilizing ability in P deficient conditions. PMID:20171856

  15. Associations between childhood adversity, adult stressful life events, and past-year drug use disorders in the National Epidemiological Study of Alcohol and Related Conditions (NESARC)

    PubMed Central

    Myers, Bronwyn; McLaughlin, Katie A.; Wang, Shuai; Blanco, Carlos; Stein, Dan J.

    2014-01-01

    Stress sensitization, whereby CA lowers tolerance to later stressors, has been proposed as a potential mechanism explaining the association between exposure to childhood adversities (CA) and drug use disorders in adulthood. However this mechanism remains untested. This paper begins to address this gap through exploring associations between CA exposure and stressful events in adulthood for predicting drug use disorders. We used data drawn from Wave 2 of the U.S. National Epidemiological Survey of Alcohol and Related Conditions (n=34,653) to explore whether the association between past-year stressful life events and the 12-month prevalence of disordered cannabis, stimulant and opiate use varied by the number of types of CA that an individual was exposed to. Past-year stressful life events were associated with an increased risk of cannabis, stimulant and opiate use disorders among men and women. Exposure to CA was associated with increased risk for disordered cannabis use among men and women and opiate use among men only. Finally, we found significant associations between exposure to CA and past year stressful life events in predicting disordered drug use, but only for women in relation to disordered stimulant and opiate use. Findings are suggestive of possible stress sensitization effects in predicting disordered stimulant and opiate use among women. Implications of these findings for the prevention and treatment of drug use disorders and for future research are discussed. PMID:25134042

  16. A new large initial condition ensemble to assess avoided impacts in a climate mitigation scenario

    NASA Astrophysics Data System (ADS)

    Sanderson, B. M.; Tebaldi, C.; Knutti, R.; Oleson, K. W.

    2014-12-01

    It has recently been demonstrated that when considering timescales of up to 50 years, natural variability may play an equal role to anthropogenic forcing on subcontinental trends for a variety of climate indicators. Thus, for many questions assessing climate impacts on such time and spatial scales, it has become clear that a significant number of ensemble members may be required to produce robust statistics (and especially so for extreme events). However, large ensemble experiments to date have considered the role of variability in a single scenario, leaving uncertain the relationship between the forced climate trajectory and the variability about that path. To address this issue, we present a new, publicly available, 15 member initial condition ensemble of 21st century climate projections for the RCP 4.5 scenario using the CESM1.1 Earth System Model, which we propose as a companion project to the existing 40 member CESM large ensemble which uses the higher greenhouse gas emission future of RCP8.5. This provides a valuable data set for assessing what societal and ecological impacts might be avoided through a moderate mitigation strategy in contrast to a fossil fuel intensive future. We present some early analyses of these combined ensembles to assess to what degree the climate variability can be considered to combine linearly with the underlying forced response. In regions where there is no detectable relationship between the mean state and the variability about the mean trajectory, then linear assumptions can be trivially exploited to utilize a single ensemble or control simulation to characterize the variability in any scenario of interest. We highlight regions where there is a detectable nonlinearity in extreme event frequency, how far in the future they will be manifested and propose mechanisms to account for these effects.

  17. Assessing potential changes of chestnut productivity in Europe under future climate conditions

    NASA Astrophysics Data System (ADS)

    Calheiros, T.; Pereira, M. G.; Pinto, J. G.; Caramelo, L.; Gomes-Laranjo, J.; Dacamara, C. C.

    2012-04-01

    The European chestnut is cultivated for its nuts and wood. Several studies point to the dependency of chestnut productivity on specific soil and climate characteristics. For instance, this species dislikes chalky and poorly drained soils, appreciates sedimentary, siliceous and acidic to neutral soils. Chestnut trees also seems to appreciate annual mean values of sunlight spanning between 2400 and 2600 h, rainfall ranging between 600 and 1500 mm, mean annual temperature between 9 and 13°C, 27°C being the mean of the maximum temperature (Heiniger and Conedera, 1992; Gomes-Laranjo et al.,2008). The amount of heat between May and October must range between 1800°D and 2400°D (Dinis et al., 2011) . In Poland, the growing season is defined as the period of time when the mean 24-h temperature is greater than 5°C (Wilczynski and Podalski, 2007). In Portugal, maximum photosynthetic activity occurs at 24-28°C for adult trees, but exhibits more than 50% of termoinhibition when the air temperature is above 32°C, which is frequent during summer (Gomes- Laranjo et al., 2006, 2008). Recently Pereira et al (2011) identified a set of meteorological variables/parameters with high impact on chestnut productivity. The main purpose of this work is to assess the potential impacts of future climate change on chestnut productivity in Portugal as well as on European chestnut orchards. First, observed data from the European Climate assessment (ECA) and simulations with the Regional Circulation Model (RCM) COSMO-CLM for recent climate conditions are used to assess the ability of the RCM to model the actual meteorological conditions. Then, ensemble projections from the ECHAM5/COSMO-CLM model chain for two climate scenarios (A1B and B1) are used to estimate the values of relevant meteorological variables and parameters und future climate conditions. Simulated values are then compared with those obtained for present climate. Results point to changes in the spatial and temporal

  18. Groundwater Supported Evapotranspiration within Glaciated Watersheds under Conditions of Climate Change

    NASA Astrophysics Data System (ADS)

    Person, M. A.; Winter, T. C.; Rosenberry, D. O.; Cohen, D.; Gutowski, W. J.; Dahlstrom, D.; Roy, P.; Emi, I.; Zabielski, V.; Wrigth, H.; Nieber, J.; Daannen, R.

    2004-05-01

    We analyze the effects of geology and geomorphology on surface water/groundwater interactions, evapotranspiration, and runoff generation under conditions of long-term climate change. Our analysis uses hydrologic data from the glaciated Crow Wing watershed in central Minnesota, USA, as well as saturated/unsaturated mathematical modeling. Analysis of historical water table (1970-1993) and lake level (1924--2002) records indicate that larger amplitude, longer period fluctuations occur within the upland portions of watersheds due to the response of the aquifer system to climatic fluctuations. Under dust-bowl type climatic conditions, lake and water table levels fell by as much as 2-4 meters in the uplands but by only a meter in the lowlands. The same pattern can be seen on millennial time scales. Analysis of Holocene lake core records indicate that Moody lake, located near the confluence of the Crow Wing and Mississippi rivers fell by as much as 4 meters between about 4400 and 7000 yr BP. During the same time period, water levels in Lake Mina, located near the watershed divide near Alexandria, MN, fell by about 15 m. These findings are consistent with analytical calculations that indicate that the response time and magnitude of water table and lake level fluctuations will be greatest near the water table divide of large watersheds. A sensitivity analysis was carried out using a transient saturated-unsaturated hydrologic model (HYDRAT2D) to study how aquifer hydraulic conductivity, land surface topography and watershed size can influence watertable fluctuations, westlands formation, evapotranspiration, and runoff. The models were run by recycling relatively wet (1985, 87 cm annual precipitation) climatic record over a period of 10 years followed by 20 years of a dryer (1976, 38~cm precipitation) and warmer climate record. Model results indicated that aquifer-supported evapotranspiration accounted for as much as 12 % (10 cm) of evapotranspiration. The highest hydraulic

  19. Transferability of SWAT model parameters for flow simulations under changed climatic conditions

    NASA Astrophysics Data System (ADS)

    Zhu, Q.; Zhang, X.; Ma, C.; Xu, Y.

    2013-12-01

    Hydrological models are widely employed for climate change impact assessment. Parameters calibration is a step of great importance in using hydrological models to simulate flows. In most studies, parameters estimated from observations are assumed to remain valid for future climate conditions. However, this might not be true due to non-stationarity. In this study, SWAT model is used to evaluate the transferability of parameters for flow simulations under changed climatic conditions. The model is set up in Quzhou catchment, one sub-basin of Qiantang River Basin in East China. After a preliminary sensitivity analysis, ten parameters are selected as sensitive ones and used in the calibration. Based on the aridity index and flows, three sub-periods are selected from the period (1961-2006): wet sub-period (1992-1995), intermediate sub-period (1965-1968) and dry sub-period (2003-2006). These three sub-periods are calibrated separately via SUFI-2 method, which results in three different sets of parameters. A regional climate model PRECIS (Providing REgional Climates for Impacts Studies) is used to downscale the global climate model (HadCM3) outputs. The downscaled precipitation and temperature are put into SWAT model to simulate future flows in the future period (2011-2040). The three sets of parameters are employed separately to simulate future flows. The results show that in the calibration the Nash-Sutcliffe coefficients of 1000 simulations which are larger than 0.6 in wet, intermediate and dry sub-periods are more than 77.3%, 97% and 71.7% respectively. By comparing the ranges of those three sets parameters, it is found that three parameters about soil are very different from each other, which are available water capacity of the soil layer, saturated hydraulic conductivity and soil depth. From the uncertainty range (95PPU) of future flow simulations, it is known that flows simulated by the wet set of parameters are similar to those by the intermediate set of parameters

  20. Changes in hydrological regime under changed climate and forest conditions in mountainous basins in Slovakia

    NASA Astrophysics Data System (ADS)

    Hlavcova, Kamila; Roncak, Peter; Maliarikova, Marcela; Latkova, Tamara; Korbelova, Lenka

    2016-04-01

    The impacts of land use and climate change on hydrological regime have been an important field of research in recent decades, especially with respect to runoff formation. Land use directly impacts basic hydrological processes, such as evapotranspiration, infiltration and runoff. The study focuses on estimating impact of land use and climate changes on runoff generation in selected mountainous basins in Slovakia. Changes in land use were represented by changes in forest distribution and composition induced by changed climate. Two climate scenarios of the daily air temperatures, specific air humidity and precipitation (KNMI A1B and MPI A1B) regionally downscaled for the territory of Slovakia until the time horizon of 2075 were applied. For simulations of runoff and other components of hydrological balance under changed conditions a distributed rainfall-runoff model was used. The simulations were done with an emphasis on the parameterization of the land cover properties (spatially distributed model parameters) and calibration of global parameters of the hydrological model in changed conditions. The outcomes of the runoff simulations indicate that changes in the long-term mean monthly discharges are expected. During the winter and early spring periods, an increase in the long-term mean monthly runoff could be assumed. The period of an increase in runoff could occur from November/December to February/April. This increase could be caused by an increase in air temperature and a shift in the snow melting period from the spring months to the winter period. The period of a decrease in runoff could occur from March/April to September/November. The increase in winter runoff and the decrease in summer runoff are expected to be more extreme for the later time horizons.

  1. Tree growth and forest ecosystem functioning in Eurasia under extreme climate conditions

    NASA Astrophysics Data System (ADS)

    Saurer, Matthias; Kirdyanov, Alexander; Prokushkin, Anatoly; Bryukhanova, Marina; Knorre, Anastasia; Nasyrov, Muhtor; Frank, David; Treydte, Kerstin; Sidorova, Olga; Siegwolf, Rolf

    2013-04-01

    The main goal of this study is to improve our understanding of the influence of a changing climate on trees in extreme conditions by a detailed analysis of the factors controlling tree-ring growth. We investigated forest ecosystems in regions that are very sensitive to climatic changes and where rapid and dramatic environmental and climatic changes are on-going, namely, the high latitude permafrost region in Central Siberia (Russia), the semi-arid dry areas in Central Asia (Uzbekistan) and high-altitude sites in the Alps (Switzerland). Tree-ring parameters studied were ring-width, density, cell number and structure and the ratio of carbon and oxygen isotopes. An important aspect of the work was the characterization of seasonal growth and water supply of trees. Intra-seasonal dynamics of tree-ring formation was correlated with monitored environmental factors, such as air and soil temperature and moisture, permafrost depth and the isotope composition of soil water, of precipitation, and of stream water. Intra-annual and long-term variability of the main tree-ring parameters were compared for the different regions. The results obtained help us to understand better tree-physiological processes valid under contrasting environmental conditions. For instance, the relationship between the onset of cell division in the cambium and the thermo-hydrological soil regime was used to determine the period of the year with the highest influence on the start of tree-ring formation. Seasonally resolved oxygen isotope depth profiles of soil water and concurrent xylem and leaf water measurements show the importance of time-lags between precipitation, leaf processes and growth. The data obtained are important for improving tree-ring growth models and estimating future tree growth under climate change. Funding: SNF SCOPES IZ73Z0_128035

  2. Thermal State Of Permafrost In Urban Environment Under Changing Climatic Conditions

    NASA Astrophysics Data System (ADS)

    Streletskiy, D. A.; Grebenets, V. I.; Kerimov, A. G.; Kurchatova, A.; Andruschenko, F.; Gubanov, A.

    2015-12-01

    Risks and damage, caused by deformation of building and constructions in cryolithozone, are growing for decades. Worsening of cryo-ecological situation and loss of engineering-geocryological safety are induced by both technogenic influences on frozen basement and climate change. In such towns on permafrost as Vorkuta, Dixon more than 60% of objects are deformed, in Yakutsk, Igarka- nearly 40%, in Norilsk, Talnakh, Mirnij 35%, in old indigenous villages - approximately 100%; more than 80% ground dams with frozen cores are in poor condition. This situation is accompanied by activation of dangerous cryogenic processes. For example in growing seasonally-thaw layer is strengthening frost heave of pipeline foundation: only on Yamburg gas condensate field (Taz Peninsula) are damaged by frost heave and cut or completely replaced 3000 - 5000 foundations of gas pipelines. Intensity of negative effects strongly depends on regional geocryology, technogenic loads and climatic trends, and in Arctic we see a temperature rise - warming, which cause permafrost temperature rise and thaw). In built areas heat loads are more diverse: cold foundations (under the buildings with ventilated cellars or near termosyphons) are close to warm areas with technogenic beddings (mainly sandy), that accumulate heat, close to underground collectors for communications, growing thaw zones around, close to storages of snows, etc. Note that towns create specific microclimate with higher air temperature. So towns are powerful technogenic (basically, thermal) presses, placed on permafrost; in cooperation with climate changes (air temperature rise, increase of precipitation) they cause permafrost degradation. The analysis of dozens of urban thermal fields, formed in variable cryological and soil conditions, showed, that nearly 70% have warming trend, 20% - cooling and in 10% of cases the situation after construction is stable. Triggered by warming of climate changes of vegetation, depth and temperature of

  3. Effects of climatic conditions and soil properties on Cabernet Sauvignon berry growth and anthocyanin profiles.

    PubMed

    Cheng, Guo; He, Yan-Nan; Yue, Tai-Xin; Wang, Jun; Zhang, Zhen-Wen

    2014-01-01

    Climatic conditions and soil type have significant influence on grape ripening and wine quality. The reported study was conducted in two "Cabernet Sauvignon (Vitis vinifera L.V)" vineyards located in Xinjiang, a semiarid wine-producing region of China during two vintages (2011 and 2012). The results indicate that soil and climate affected berry growth and anthocyanin profiles. These two localities were within a distance of 5 km from each other and had soils of different physical and chemical composition. For each vineyard, the differences of anthocyanin concentrations, and parameters concerning berry growth and composition between the two years could be explained by different climatic conditions. Soil effect was studied by investigation of differences in berry composition and anthocyanin profiles between the two vineyards in the same year, which could be explained mainly by the different soil properties, vine water and nitrogen status. Specifically, the soils with less water and organic matter produced looser clusters, heavier berry skins and higher TSS, which contributed to the excellent performance of grapes. Compared with 2011, the increases in anthocyanin concentrations for each vineyard in 2012 could be attributed to smaller number of extreme temperature (>35 °C) days and rainfall, lower vine water status and N level. The explanation for higher anthocyanin concentrations in grape skins from the soils with less water and organic matter could be the vine status differences, lighter berry weight and heavier skin weight at harvest. In particular, grapes from the soils with less water and organic matter had higher levels of 3'5'-substituded, O-methylated and acylated anthocyanins, which represented a positive characteristic conferring more stable pigmentation to the corresponding wine in the future. The present work clarifies the effects of climate and soil on berry growth and anthocyanin profiles, thus providing guidance for production of high-quality wine grapes

  4. Pathways towards risk: syndemic conditions mediate the effect of adversity on HIV risk behaviors among young men who have sex with men (YMSM).

    PubMed

    Herrick, Amy; Stall, Ron; Egan, James; Schrager, Sheree; Kipke, Michele

    2014-10-01

    Research shows that young men who have sex with men (YMSM) engage in higher rates of health risk behaviors and experience higher rates of negative health outcomes than their peers. The purpose of this study is to determine if the effects of adversity on HIV risk are mediated by syndemics (co-occurring health problems). Participants were 470 ethnically diverse YMSM ages 18 to 24 recruited between 2005 and 2006 and surveyed every 6 months for 24 months. Regression analyses examined the impact of adversity on syndemics (emotional distress, substance use, and problematic alcohol use) and the effects of both adversity and syndemics on HIV risk behaviors over time. Gay-related discrimination and victimization-among other adversity variables-were significantly associated with syndemics and condomless sex (CS). Syndemics mediated the effects of adversity on CS in all models. Adverse events impact HIV risk taking among YMSM through syndemics. These findings suggest that prevention programs aimed at reducing adversity may reduce both the synergistic effect of multiple psychosocial health problems and HIV risk taking. PMID:25146488

  5. Sustainability of socio-hydro system with changing value and preference to an uncertain future climate and economic conditions.

    NASA Astrophysics Data System (ADS)

    Roobavannan, Mahendran; Kandasamy, Jaya; Vigneswaran, Saravanamuththu; Sivapalan, Murugesu

    2016-04-01

    Water-human systems are coupled and display co-evolutionary dynamics influenced by society's values and preference. This has been observed in the Murrumbidgee basin, Australia where water usage initially focused on agriculture production and until mid-1990's favoured agriculture. This turned around as society became more concerned about the degradation of ecosystems and ultimately water was reallocated back towards the environment. This new water management adversely impacted the agriculture sector and created economic stress in the basin. The basin communities were able to transform and cope with water allocation favouring the environment through sectoral transformation facilitated by movement of capital in a free economy, supported by appropriate strategies and funding. This was helped by the adaptive capacity of people through reemployment in other economic sectors of the basin economy, unemployment for a period of time and migration out of the basin, and crop diversification. This study looks to the future and focuses on how water managers could be informed and prepare for un-foreseen issues coming out of societies changing values and preferences and emerging as different systems in the basin interact with each other at different times and speed. The issues of this type that concern the Murray Darling Basin Authority include a renewed focus and priority on food production due to food scarcity; increased impact and frequency of natural disasters (eg. climate change); regional economic diversification due to the growth of peri-urban development in the basin; institutional capacity for water reform due to new political paradigms (eg. new water sharing plans); and improvement in science and technology (eg. farm practices, water efficiency, water reuse). To undertake this, the study uses a coupled socio-hydrological dynamical system that model the major drivers of changing economic conditions, society values and preference, climatic condition and science and

  6. Investigating the long-term landscape evolution for various combinations of climatic and geologic conditions

    NASA Astrophysics Data System (ADS)

    Paik, K.; Kim, W.

    2012-12-01

    Landscape evolution is a continuous process driven by fluvial, tectonic, and biological processes among others. The response of landscape to different combinations of tectonic and climatic conditions has been a core subject of studying the Earth surface processes. While actual landscapes exhibit highly complex settings, it would be ideal if we can understand basic behavior of landscape under simplest conditions. To pursue this desire, we investigate how a theoretical landscape develops under ideal combinations using a numerical model named LEGS [Paik, 2012]. We investigate various combinations of tectonic uplift conditions, sinusoidal precipitation time series, and orographic effects and will present scientific insights obtained from the simple combinations. Keywords: Landscape evolution, Surface process models, Orographic rainfall Paik, K. (2012) Simulation of landscape evolution using global flow path search, Environmental Modelling & Software, 33, 35-47

  7. Should flood regimes change in a warming climate? The role of antecedent moisture conditions

    NASA Astrophysics Data System (ADS)

    Woldemeskel, Fitsum; Sharma, Ashish

    2016-07-01

    Assessing changes to flooding is important for designing new and redesigning existing infrastructure to withstand future climates. While there is speculation that floods are likely to intensify in the future, this question is often difficult to assess due to inadequate records on streamflow extremes. An alternate way of determining possible extreme flooding is through assessment of the two key factors that lead to the intensification of floods: the intensification of causative rainfall and changes in the wetness conditions prior to rainfall. This study assesses global changes in the antecedent wetness prior to extreme rainfall. Our results indicate a significant increase in the antecedent moisture in Australia and Africa over the last century; however, there was also a decrease in Eurasia and insignificant change in North America. Given the nature of changes found in this study, any future flood assessment for global warming conditions should take into account antecedent moisture conditions.

  8. Multisensor System for Isotemporal Measurements to Assess Indoor Climatic Conditions in Poultry Farms

    PubMed Central

    Bustamante, Eliseo; Guijarro, Enrique; García-Diego, Fernando-Juan; Balasch, Sebastián; Hospitaler, Antonio; Torres, Antonio G.

    2012-01-01

    The rearing of poultry for meat production (broilers) is an agricultural food industry with high relevance to the economy and development of some countries. Periodic episodes of extreme climatic conditions during the summer season can cause high mortality among birds, resulting in economic losses. In this context, ventilation systems within poultry houses play a critical role to ensure appropriate indoor climatic conditions. The objective of this study was to develop a multisensor system to evaluate the design of the ventilation system in broiler houses. A measurement system equipped with three types of sensors: air velocity, temperature and differential pressure was designed and built. The system consisted in a laptop, a data acquisition card, a multiplexor module and a set of 24 air temperature, 24 air velocity and two differential pressure sensors. The system was able to acquire up to a maximum of 128 signals simultaneously at 5 second intervals. The multisensor system was calibrated under laboratory conditions and it was then tested in field tests. Field tests were conducted in a commercial broiler farm under four different pressure and ventilation scenarios in two sections within the building. The calibration curves obtained under laboratory conditions showed similar regression coefficients among temperature, air velocity and pressure sensors and a high goodness fit (R2 = 0.99) with the reference. Under field test conditions, the multisensor system showed a high number of input signals from different locations with minimum internal delay in acquiring signals. The variation among air velocity sensors was not significant. The developed multisensor system was able to integrate calibrated sensors of temperature, air velocity and differential pressure and operated succesfully under different conditions in a mechanically-ventilated broiler farm. This system can be used to obtain quasi-instantaneous fields of the air velocity and temperature, as well as differential

  9. Behavior of crushed rock aggregates used in road construction exposed to cold climate conditions

    NASA Astrophysics Data System (ADS)

    Kuznetsova, Elena; Pérez Fortes, Ana Patricia; Anastasio, Sara; Willy Danielsen, Svein

    2016-04-01

    Presently, about 90% of the aggregate production in Europe comes from naturally occurring resources: quarries and pits. Due to the increased demand for sand and gravel for construction purposes, not only in building but also in road construction, the last decade has seen a significant trend towards the use of more crushed rock aggregates. This resource has been more and more preferred to sand and gravel thanks to the significant technological development of its process and use phase. The performance of the aggregates is generally evaluated depending on three main factors: the geological origin (mineral composition, texture, structure, degree of weathering), the aggregate processing (crushing, sieving, washing, storing) and the user technology for a specific area of use (e.g. road construction, asphalt binders). Nevertheless climatic conditions should carefully be taken into account in application such as road construction. Large temperature gradients and high levels of humidity are known to significantly affect the performance of the material. Although the problem is, at least in the asphalt field, considered mostly from the binder point of view, this article aims to investigate the effect of aggregate properties on road performance in cold climatic conditions. Two different climatic areas will be taken into account: Norway and Spain. While both these countries are listed among the main European producers of aggregates, they represent significantly different climatic regions. While Norwegian weather is characterized by humid cold winters and relatively mild summers, Spain has temperate climate with cold regions in mountainous and internal areas. Both countries have been significantly affected by climate change with increasing temperature variations and instability. At the same time, similar winter maintenance measures, including the use of a considerable amount of solid and liquid chemicals to avoid ice formation (e.g. NaCl) and/or to provide better friction, are

  10. The Impact of Organic Amendments on Soil Properties Under Mediterranean Climatic Conditions

    NASA Astrophysics Data System (ADS)

    Hueso Gonzalez, Paloma; Francisco Martinez Murillo, Juan; Damian Ruiz Sinoga, Jose

    2014-05-01

    Soil erosion and unsustainable land uses produce adverse effect on SOC content. Soil management techniques and corrections can be applied for soil recovery, especially, with afforestation purposes. This study presents the short term effects of the application of different treatments and amendments on soil properties for soils included in several sets of closed plots located in the experimental area of Pinarillo (Nerja, Spain). The analysed soil properties were: pH, EC, Organic Carbon, total Nitrogen and total Carbon. In order to verify possible differences, we applied the test of Mann-Whitney U in corroboration with the previous homogeneity test of variance. The result of each strategy set compared to the initial condition shows at least one significant modification in the analysed soil properties. Electrical conductivity was the most changeable soil property respect to the initial condition. Similarly, organic carbon content and total organic carbon remained quite similar. However, when all of the strategy sets are compared among them, total carbon was the most significantly changeable property. Mulching, polymers and urban residue seem to highly modify the soil initial conditions. Although soil physic-chemical parameters generally used to evaluate soil quality change very slowly. The analysed soil properties shows significant differences between dry and wet season. This fact, could be indicating the effect of certain seasonality as it is usual in Mediterranean condition.

  11. [Relationships between biochemical qualities of paddy rice and climate conditions in the Anning River Valley].

    PubMed

    Peng, Guozhao; Bai, Jian; Wang, Jingbo

    2004-12-01

    Based on the experimental data of paddy rice planted geographically periodically without control in the Anning River Valley of Sichuan Province, this paper quantitatively analyzed the effects of meteorological conditions from 40 days before heading to ripeness on the biochemical qualities of paddy rice, and developed a model about the integrated relationships between biochemical qualities of paddy rice and mean temperature, daily range of temperature and daylight hours, which would be of significance both for the instruction of paddy distribution in the Anning River Valley and for improving rice qualities via adjusting planting time. The results showed that climate conditions had a great effect on the biochemical qualities of paddy rice, which was different in ways and in critical periods. The period when the correlation between some ingredients of rice and climate conditions was most significant was before or after, or from before to after full heading, which widened the existing knowledge about the period which was important for paddy rice qualities forming. Applying this finding in the Anning River Valley during 2002-2003, the accumulated high-grade paddy farming area stood at 73,000 hm2, 30,000 hm2 more than that in 2001, and brought 0.2 billion yuan increment to the peasants, promoting the development of high-grade paddy greatly. PMID:15825441

  12. The influence of the sun, moon, climate and economic conditions on crisis incidence.

    PubMed

    Snoyman, P; Holdstock, T L

    1980-10-01

    Investigated the relationship between 2,344 cases of crisis incidence over a 1-year period (1976) and geophysical, climatic and seasonal conditions. Results revealed an intricate interactive effect between the variables of sex, nature of crisis, period of analysis, and environmental conditions. Males crisis became more likely, with downward economic trends or decreased solar activity. In contrast to female incidence of crisis, which peaked in spring, that of males peaked in autumn. Increased solar activity was related strongly to the incidence of crisis experienced by people who were retarded, abused drugs and were guilty of assault and/or rape. The waxing of the moon was related closely to cases of assault and/or rape, while retardates were influenced further by the moisture content in the air. Temporal considerations revealed a positive relationship between full moon and crisis incidence on alternate months only. Generally, the increased cloud cover, rainfall and temperature in summer, gave rise to more crisis consultations. Finally, geophysical, climatic and economic conditions also were seen to act in conjunction with each other to influence crisis incidence. PMID:7440740

  13. Health hazards in areas of military operations conducted in different climatic and sanitary conditions.

    PubMed

    Korzeniewski, Krzysztof

    2011-01-01

    This paper reviews the most common health hazards occurring among personnel of peacekeeping and stabilization missions functioning within armed conflicts in the contemporary world. Military operations have been executed in diverse climatic and sanitary conditions, which are frequently unfamiliar for their participants. Some of them, e.g. the UN peacekeeping missions in the Middle East (Lebanon, the Golan Heights), have been carried out in a relatively stable geopolitical environment; whereas, stabilization missions in Iraq and Afghanistan, which are actually combat activities, undoubtedly fall into the group of the most perilous military operations in the world. Hot or cold climate, poor sanitary and hygienic conditions along with warfare facilitate the occurrence of numerous diseases and body injuries not only among the local people but also among peacekeepers, who represent the population of immigrants. Health hazards which pose major epidemiological threats in combat zones are arthropod-borne, food and water-borne, respiratory tract diseases, sexually transmitted diseases, enzootic diseases, battle injuries, and non- -battle injuries, e.g. traffic accidents. Another considerable health problem are psychiatric disorders, which can either appear directly after the occurrence of a traumatic event in a combat zone or indirectly, after some time had elapsed. In addition to the health hazards listed above, environmental factors such as changeable weather conditions and local fauna may also be life threatening. PMID:21534225

  14. Climate change reverses the competitive balance of ash and beech seedlings under simulated forest conditions.

    PubMed

    Saxe, H; Kerstiens, G

    2005-07-01

    This study identifies the important role of climate change and photosynthetic photon flux density (PPFD) in the regenerative competence of ash and beech seedlings in 12 inter- and intra-specific competition designs in simulated mixed ash-beech forest gaps under conditions of non-limiting soil volume, water and nutrient supply. The growth conditions simulated natural forest conditions as closely as possible. Simulations were performed by growing interacting seedling canopies for one season in temperature-regulated closed-top chambers (CTCs). Eight CTCs were used in a factorial design with replicate treatments of [CO2] x temperature x PPFD x competition design. [CO2] tracked ambient levels or was 360 micromol mol-1 higher. Temperature tracked ambient levels or was 2.8 degrees C higher. PPFD on two plant tables inside each CTC was 16% and 5% of open-field levels, respectively, representative of typical light flux levels in a natural forest gap. In several of the competition designs, climate change made the ash seedlings grow taller than the beech seedlings and, at the same time, attain a larger leaf area and a larger total biomass. Advantages of this type for ash were found particularly at lower PPFD. There was a positive synergistic interaction of elevated temperature x [CO2] for both species, but more so for ash. There are many uncertainties when a study of chambered seedlings is to be projected to real changes in natural forests. Nevertheless, this study supports a possible future shift towards ash in north European, unmanaged, mixed ash-beech forests in response to the predicted climate change. PMID:16025410

  15. Small Scale Solar Cooling Unit in Climate Conditions of Latvia: Environmental and Economical Aspects

    NASA Astrophysics Data System (ADS)

    Jaunzems, Dzintars; Veidenbergs, Ivars

    2010-01-01

    The paper contributes to the analyses from the environmental and economical point of view of small scale solar cooling system in climate conditions of Latvia. Cost analyses show that buildings with a higher cooling load and full load hours have lower costs. For high internal gains, cooling costs are around 1,7 €/kWh and 2,5 €/kWh for buildings with lower internal gains. Despite the fact that solar cooling systems have significant potential to reduce CO2 emissions due to a reduction of electricity consumption, the economic feasibility and attractiveness of solar cooling system is still low.

  16. Sensitivity of salmonid freshwater life history in western US streams to future climate conditions.

    PubMed

    Beer, W Nicholas; Anderson, James J

    2013-08-01

    We projected effects of mid-21st century climate on the early life growth of Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) in western United States streams. Air temperature and snowpack trends projected from observed 20th century trends were used to predict future seasonal stream temperatures. Fish growth from winter to summer was projected with temperature-dependent models of egg development and juvenile growth. Based on temperature data from 115 sites, by mid-21st century, the effects of climate change are projected to be mixed. Fish in warm-region streams that are currently cooled by snow melt will grow less, and fish in suboptimally cool streams will grow more. Relative to 20th century conditions, by mid-21st century juvenile salmonids' weights are expected to be lower in the Columbia Basin and California Central Valley, but unchanged or greater in coastal and mountain streams. Because fish weight affects fish survival, the predicted changes in weight could impact population fitness depending on other factors such as density effects, food quality and quantity changes, habitat alterations, etc. The level of year-to-year variability in stream temperatures is high and our analysis suggests that identifying effects of climate change over the natural variability will be difficult except in a few streams. PMID:23640715

  17. A global map of suitability for coastal Vibrio cholerae under current and future climate conditions.

    PubMed

    Escobar, Luis E; Ryan, Sadie J; Stewart-Ibarra, Anna M; Finkelstein, Julia L; King, Christine A; Qiao, Huijie; Polhemus, Mark E

    2015-09-01

    Vibrio cholerae is a globally distributed water-borne pathogen that causes severe diarrheal disease and mortality, with current outbreaks as part of the seventh pandemic. Further understanding of the role of environmental factors in potential pathogen distribution and corresponding V. cholerae disease transmission over time and space is urgently needed to target surveillance of cholera and other climate and water-sensitive diseases. We used an ecological niche model (ENM) to identify environmental variables associated with V. cholerae presence in marine environments, to project a global model of V. cholerae distribution in ocean waters under current and future climate scenarios. We generated an ENM using published reports of V. cholerae in seawater and freely available remotely sensed imagery. Models indicated that factors associated with V. cholerae presence included chlorophyll-a, pH, and sea surface temperature (SST), with chlorophyll-a demonstrating the greatest explanatory power from variables selected for model calibration. We identified specific geographic areas for potential V. cholerae distribution. Coastal Bangladesh, where cholera is endemic, was found to be environmentally similar to coastal areas in Latin America. In a conservative climate change scenario, we observed a predicted increase in areas with environmental conditions suitable for V. cholerae. Findings highlight the potential for vulnerability maps to inform cholera surveillance, early warning systems, and disease prevention and control. PMID:26048558

  18. Sensitivity of Latent Heating Profiles to Environmental Conditions: Implications for TRMM and Climate Research

    NASA Technical Reports Server (NTRS)

    Shepherd, J. Marshall; Einaudi, Franco (Technical Monitor)

    2000-01-01

    The Tropical Rainfall Measuring Mission (TRMM) as a part of NASA's Earth System Enterprise is the first mission dedicated to measuring tropical rainfall through microwave and visible sensors, and includes the first spaceborne rain radar. Tropical rainfall comprises two-thirds of global rainfall. It is also the primary distributor of heat through the atmosphere's circulation. It is this circulation that defines Earth's weather and climate. Understanding rainfall and its variability is crucial to understanding and predicting global climate change. Weather and climate models need an accurate assessment of the latent heating released as tropical rainfall occurs. Currently, cloud model-based algorithms are used to derive latent heating based on rainfall structure. Ultimately, these algorithms can be applied to actual data from TRMM. This study investigates key underlying assumptions used in developing the latent heating algorithms. For example, the standard algorithm is highly dependent on a system's rainfall amount and structure. It also depends on an a priori database of model-derived latent heating profiles based on the aforementioned rainfall characteristics. Unanswered questions remain concerning the sensitivity of latent heating profiles to environmental conditions (both thermodynamic and kinematic), regionality, and seasonality. This study investigates and quantifies such sensitivities and seeks to determine the optimal latent heating profile database based on the results. Ultimately, the study seeks to produce an optimized latent heating algorithm based not only on rainfall structure but also hydrometeor profiles.

  19. Methane emission from Russian frozen wetlands under conditions of climate change

    NASA Astrophysics Data System (ADS)

    Reneva, S.

    2009-04-01

    There is growing evidence that the climate change will have significant impact on permafrost, leading to warming, thawing, and disappearance of the frozen ground. Arctic soils contain 14%-30% of all the carbon stored in soils worldwide, many of which is accumulated in the Arctic wetlands (Anisimov & Reneva 2006). Wetlands occupy almost 2 million km2 in the circumpolar region, contain about 50 Gt C, and because of the high groundwater levels favour the production of methane in the anaerobic carbon-rich soil layer (Anisimov et al 2005). Methane has 21-times stronger greenhouse effect than the equal amount of CO2, and there are growing concerns that enhanced CH4 emission may have significant effect on the global radiative forcing. The goal of our study was to estimate the potential increase in the methane emission from Russian frozen wetlands under the projected for the mid-21st century climatic conditions and to evaluate the effect it may have on global radiative forcing. We used digital geographically referenced contours of Russian wetlands from 1:1,000,000-scale topographic maps to calculate the total area (350 000 km2) and the fraction of land they occupy in the nodes of 0.5 by 0.5 degree lat/long regular grid spanning permafrost regions. These data were overlaid with the results from predictive permafrost model (Anisimov & Belolutskaia 2003, Anisimov et al 1999) forced by CCC, HadCM3, GFDL, NCAR climatic projections for 2050 under B1 emission scenario (ref. http://ipcc-ddc.cru.uea.ac.uk/ and http://igloo.atmos.uiuc.edu/IPCC/). Ultimately, we calculated the increase in the amount of organic material that may potentially become available for decomposition due to deeper seasonal thawing of wetlands in the Russian part of Arctic. Following (Christensen et al 2003a, Christensen et al 2003b) we hypothesised that the temperature and substrate availability combined explain almost entirely the variations in mean annual methane emissions. We used the results of numerous

  20. Groundwater-supported evapotranspiration within glaciated watersheds under conditions of climate change

    NASA Astrophysics Data System (ADS)

    Cohen, Denis; Person, Mark; Daannen, Ronnie; Locke, Sharon; Dahlstrom, Dave; Zabielski, Victor; Winter, Thomas C.; Rosenberry, Donald O.; Wright, Herb; Ito, Emi; Nieber, John L.; Gutowski, William J.

    2006-04-01

    This paper analyzes the effects of geology and geomorphology on surface-water/-groundwater interactions, evapotranspiration, and recharge under conditions of long-term climatic change. Our analysis uses hydrologic data from the glaciated Crow Wing watershed in central Minnesota, USA, combined with a hydrologic model of transient coupled unsaturated/saturated flow (HYDRAT2D). Analysis of historical water-table (1970-1993) and lake-level (1924-2002) records indicates that larger amplitude and longer period fluctuations occur within the upland portions of watersheds due to the response of the aquifer system to relatively short-term climatic fluctuations. Under drought conditions, lake and water-table levels fell by as much as 2-4 m in the uplands but by 1 m in the lowlands. The same pattern can be seen on millennial time scales. Analysis of Holocene lake-core records indicates that Moody Lake, located near the outlet of the Crow Wing watershed, fell by as much as 4 m between about 4400 and 7000 yr BP. During the same time, water levels in Lake Mina, located near the upland watershed divide, fell by about 15 m. Reconstructed Holocene climate as represented by HYDRAT2D gives somewhat larger drops (6 and 24 m for Moody Lake and Lake Mina, respectively). The discrepancy is probably due to the effect of three-dimensional flow. A sensitivity analysis was also carried out to study how aquifer hydraulic conductivity and land-surface topography can influence water-table fluctuations, wetlands formation, and evapotranspiration. The models were run by recycling a wet year (1985, 87 cm annual precipitation) over a 10-year period followed by 20 years of drier and warmer climate (1976, 38 cm precipitation). Model results indicated that groundwater-supported evapotranspiration accounted for as much as 12% (10 cm) of evapotranspiration. The aquifers of highest hydraulic conductivity had the least amount of groundwater-supported evapotranspiration owing to a deep water table. Recharge

  1. Groundwater-supported evapotranspiration within glaciated watersheds under conditions of climate change

    USGS Publications Warehouse

    Cohen, D.; Person, M.; Daannen, R.; Locke, S.; Dahlstrom, D.; Zabielski, V.; Winter, T.C.; Rosenberry, D.O.; Wright, H.; Ito, E.; Nieber, J.L.; Gutowski, W.J., Jr.

    2006-01-01

    This paper analyzes the effects of geology and geomorphology on surface-water/-groundwater interactions, evapotranspiration, and recharge under conditions of long-term climatic change. Our analysis uses hydrologic data from the glaciated Crow Wing watershed in central Minnesota, USA, combined with a hydrologic model of transient coupled unsaturated/saturated flow (HYDRAT2D). Analysis of historical water-table (1970-1993) and lake-level (1924-2002) records indicates that larger amplitude and longer period fluctuations occur within the upland portions of watersheds due to the response of the aquifer system to relatively short-term climatic fluctuations. Under drought conditions, lake and water-table levels fell by as much as 2-4 m in the uplands but by 1 m in the lowlands. The same pattern can be seen on millennial time scales. Analysis of Holocene lake-core records indicates that Moody Lake, located near the outlet of the Crow Wing watershed, fell by as much as 4 m between about 4400 and 7000 yr BP. During the same time, water levels in Lake Mina, located near the upland watershed divide, fell by about 15 m. Reconstructed Holocene climate as represented by HYDRAT2D gives somewhat larger drops (6 and 24 m for Moody Lake and Lake Mina, respectively). The discrepancy is probably due to the effect of three-dimensional flow. A sensitivity analysis was also carried out to study how aquifer hydraulic conductivity and land-surface topography can influence water-table fluctuations, wetlands formation, and evapotranspiration. The models were run by recycling a wet year (1985, 87 cm annual precipitation) over a 10-year period followed by 20 years of drier and warmer climate (1976, 38 cm precipitation). Model results indicated that groundwater-supported evapotranspiration accounted for as much as 12% (10 cm) of evapotranspiration. The aquifers of highest hydraulic conductivity had the least amount of groundwater-supported evapotranspiration owing to a deep water table. Recharge

  2. Establishment and performance of an experimental green roof under extreme climatic conditions.

    PubMed

    Klein, Petra M; Coffman, Reid

    2015-04-15

    Green roofs alter the surface energy balance and can help in mitigating urban heat islands. However, the cooling of green roofs due to evapotranspiration strongly depends on the climatic conditions, and vegetation type and density. In the Southern Central Plains of the United States, extreme weather events, such as high winds, heat waves and drought conditions pose challenges for successful implementation of green roofs, and likely alter their standard performance. The National Weather Center Experimental Green Roof, an interdisciplinary research site established in 2010 in Norman, OK, aimed to investigate the ecological performance and surface energy balance of green roof systems. Starting in May 2010, 26 months of vegetation studies were conducted and the radiation balance, air temperature, relative humidity, and buoyancy fluxes were monitored at two meteorological stations during April-October 2011. The establishment of a vegetative community trended towards prairie plant dominance. High mortality of succulents and low germination of grasses and herbaceous plants contributed to low vegetative coverage. In this condition succulent diversity declined. Bouteloua gracilis and Delosperma cooperi showed typological dominance in harsh climatic conditions, while Sedum species experienced high mortality. The plant community diversified through volunteers such as Euphorbia maculate and Portulaca maculate. Net radiation measured at a green-roof meteorological station was higher than at a control station over the original, light-colored roofing material. These findings indicate that the albedo of the green roof was lower than the albedo of the original roofing material. The low vegetative coverage during the heat and drought conditions in 2011, which resulted in the dark substrate used in the green roof containers being exposed, likely contributed to the low albedo values. Nevertheless, air temperatures and buoyancy fluxes were often lower over the green roof indicating

  3. Development of Streamflow Projections under Changing Climate Conditions over Colorado River Basin Headwaters

    NASA Astrophysics Data System (ADS)

    Miller, W. P.; Piechota, T. C.; Gangopadhyay, S.; Pruitt, T.

    2010-12-01

    The current drought over the Colorado River Basin has raised concerns that the U.S. Department of the Interior, Bureau of Reclamation (Reclamation) may impose water shortages over the lower portion of the basin for the first time in history. The guidelines that determine levels of shortage are impacted by forecasts developed by the Colorado Basin River Forecast Center (CBRFC). While these forecasts by the CBRFC are useful, water managers within the basin are interested in long-term projections of streamflow, particularly under changing climate conditions. Here, a bias-corrected, statistically downscaled dataset of projected climate is used to force the National Weather Service (NWS) River Forecasting System (RFS) utilized by the CBRFC to derive projections of streamflow over the Green, Gunnison, and San Juan River headwater basins located within the Colorado River Basin. The NWS RFS is modified to evaluate the impact of changing climate to evapotranspiration rates. Adjusting evapotranspiration demands over the Gunnison resulted in a 6% to 13% average decrease in runoff over the Gunnison River Basin when compared to static evapotranspiration rates. Streamflow projections derived using projections of future climate and the NWS RFS resulted in decreased runoff in 2 of the 3 basins considered. Over the Gunnison and San Juan River basins, a 10% to 15% average decrease in basin runoff is projected through the year 2099. However, over the Green River basin, a 5% to 8% increase in basin runoff is projected through 2099. Evidence of nonstationary behavior is apparent over the Gunnison and San Juan River basins.

  4. Development of streamflow projections under changing climate conditions over Colorado River Basin headwaters

    NASA Astrophysics Data System (ADS)

    Miller, W. P.; Piechota, T. C.; Gangopadhyay, S.; Pruitt, T.

    2010-08-01

    The current drought over the Colorado River Basin has raised concerns that the US Department of the Interior, Bureau of Reclamation (Reclamation) may impose water shortages over the lower portion of the basin for the first time in history. The guidelines that determine levels of shortage are affected by forecasts determined by the Colorado Basin River Forecast Center (CBRFC). While these forecasts by the CBRFC are useful, water managers within the basin are interested in long-term projections of streamflow, particularly under changing climate conditions. In this study, a bias-corrected, statistically downscaled dataset of projected climate is used to force a hydrologic model utilized by the CBRFC to derive projections of streamflow over the Green, Gunnison, and San Juan River headwater basins located within the Colorado River Basin. This study evaluates the impact of changing climate to evapotranspiration rates. The impact to evapotranspiration rates is taken into consideration and incorporated into the development of streamflow projections over Colorado River headwater basins in this study. Additionally, the CBRFC hydrologic model is modified to account for impacts to evapotranspiration due to changing temperature over the basin. Adjusting evapotranspiration demands over the Gunnison resulted in a 6% to 13% average decrease in runoff over the Gunnison River Basin when compared to static evapotranspiration rates. Streamflow projections derived using projections of future climate and the CBRFC's hydrologic model resulted in decreased runoff in 2 of the 3 basins considered. Over the Gunnison and San Juan River basins, a 10% to 15% average decrease in basin runoff is projected through the year 2099. However, over the Green River basin, a 5% to 8% increase in basin runoff is projected through 2099. Evidence of nonstationary behavior is apparent over the Gunnison and San Juan River basins.

  5. Storm surges in the Mediterranean Sea: Variability and trends under future climatic conditions

    NASA Astrophysics Data System (ADS)

    Androulidakis, Yannis S.; Kombiadou, Katerina D.; Makris, Christos V.; Baltikas, Vassilis N.; Krestenitis, Yannis N.

    2015-09-01

    The trends of storm surge extremes in the Mediterranean Sea for a period of 150 years (1951-2100) are explored, using a high-resolution storm surge model. Numerical simulations are forced by the output of regional climate simulations with RegCM3, which uses IPCC's historical data on greenhouse gasses emissions for the (past) period 1951-2000, and IPCC's A1B climate scenario for the (future) period 2001-2100. Comparisons between observations and modeling results show good agreement and confirm the ability of our model to estimate the response of the sea surface to future climatic conditions. We investigate the future trends, the variability and frequency of local extremes and the main forcing mechanisms that can induce strong surges in the Mediterranean region. Our results support that there is a general decreasing trend in storminess under the considered climate scenario, mostly related to the frequency of local peaks and the duration and spatial coverage of the storm surges. The northward shift in the location of storm tracks is a possible reason for this storminess attenuation, especially over areas where the main driving factor of extreme events is the inverted barometer effect. However, the magnitudes of sea surface elevation extremes may increase in several Mediterranean sub-regions, i.e., Southern Adriatic, Balearic and Tyrrhenian Seas, during the 21st century. There are clear distinctions in the contributions of winds and pressure fields to the sea level height for various regions of the Mediterranean Sea, as well as on the seasonal variability of extreme values; the Aegean and Adriatic Seas are characteristic examples, where high surges are predicted to be mainly induced by low pressure systems and favorable winds, respectively.

  6. Climate and Health Vulnerability to Vector-Borne Diseases: Increasing Resilience under Climate Change Conditions in Africa

    NASA Astrophysics Data System (ADS)

    Ceccato, P.

    2015-12-01

    The International Research Institute for Climate and Society (IRI), the City University of New York (CUNY) and NASA Jet Propulsion Laboratory (JPL) in collaboration with NASA SERVIR are developing tools to monitor climate variables (precipitation, temperature, vegetation, water bodies, inundation) that help projects in Africa to increase resilience to climate change for vector-borne diseases ( malaria, trypanosomiasis, leishmaniasis, and schistosomiasis). Through the development of new products to monitor precipitation, water bodies and inundation, IRI, CUNY and JPL provide tools and capacity building to research communities; ministries of health; the WMO Global Framework for Climate and Services; and World Health Organization in Africa to: 1) Develop research teams' ability to appropriately use climate data as part of their research 2) Enable research teams and ministries to integrate climate information into social and economic drivers of vulnerability and opportunities for adaptation to climate change 3) Inform better policies and programs for climate change adaptation. This oral presentation will demonstrate how IRI, CUNY, and JPL developed new products, tools and capacity building to achieve the three objectives mentioned above with examples in South Africa, Zimbabwe, Tanzania and Malawi.

  7. Effects of climate warming, North Atlantic Oscillation, and El Niño-Southern Oscillation on thermal conditions and plankton dynamics in northern hemispheric lakes.

    PubMed

    Gerten, Dieter; Adrian, Rita

    2002-03-01

    Impacts of climate warming on freshwater ecosystems have been documented recently for a variety of sites around the globe. Here we provide a review of studies that report long-term (multidecadal) effects of warming trends on thermal properties and plankton dynamics in northern hemispheric lakes. We show that higher lake temperatures, shorter periods with ice cover, and shorter stagnation periods were common trends for lakes across the hemisphere in response to the warmer conditions. Only for shallow dimictic lakes was it observed that deep-water temperatures decreased. Moreover, it became evident that phytoplankton dynamics and primary productivity altered in conjunction with changes in lake physics. Algal spring blooms developed early and were more pronounced in several European lakes after mild winters with short ice cover periods, and primary productivity increased in North American lakes. Effects of elevated temperatures on zooplankton communities were seen in an early development of various species and groups, as is documented for cladocerans, copepods, and rotifers in European lakes. Furthermore, thermophile species reached higher abundance in warmer years. Obviously, the nature of responses is species specific, and depends on the detailed seasonal patterning of warming. Complex responses such as effects propagating across trophic levels are likely, indicating that observed climate-ecosystem relationships are not generally applicable. Nonetheless, the picture emerges that climate-driven changes in freshwater ecosystems may be synchronised to a certain extent among lakes even over great distances if climatic influences are not masked by anthropogenic impacts or differences in lake morphology. Macro-scale climatic fluctuations--such as the North Atlantic Oscillation or the El Niño-Southern Oscillation--were identified as the most important candidates responsible for such coherence, with the former predominating in Europe and the latter in North America. We

  8. Future climate impact on unfavorable meteorological conditions for the dispersion of air pollution in Brussels

    NASA Astrophysics Data System (ADS)

    De Troch, Rozemien; Berckmans, Julie; Giot, Olivier; Hamdi, Rafiq; Termonia, Piet

    2015-04-01

    Belgium is one of the several countries in Europe where air quality levels of different pollutants such as ozone, NOx, and Particulate Matter (PM) still exceed the prescribed European norms multiple times a year (EEA, 2014). These pollution peaks have a great impact on health and environment, in particular in large cities and urban environments. It is well known that observed concentrations of air pollutants are strongly influenced by emissions and meteorological conditions and therefore is sensitive to climate change. As the effects of global climate change are increasingly felt in Belgium, policy makers express growing interest in quantifying its effect on air pollution and the effort required to meet the air quality targets in the next years and decennia (Lauwaet et al., 2014). In this study, two different stability indices are calculated for a 9-year period using present (1991-1999) and future (2047-2055) climate data that has been obtained from a dynamically downscaling of Global Climate Model data from the Arpège model using the ALARO model at 4 km spatial resolution. The ALARO model is described in detail in previous validation studies from De Troch et al. (2013) and Hamdi et al. (2013). The first index gives a measure of the horizontal and vertical transport of nonreactive pollutants in stable atmospheric conditions and has been proposed and tested by Termonia and Quinet (2004). It gives a characteristic length scale l which is the ratio of the mean horizontal wind speed and the Brunt-Väisälä frequency. In this way low values for l in the lower part of the boundary layer during an extended time span of 12 hours, correspond to calm situations and a stable atmosphere and thus indicate unfavorable conditions for the dispersion of air pollution. This transport index is similar to an index used in an old Pasquill-type scheme but is more convenient to use to detect the strongest pollution peaks. The well known Pasquill classes are also calculated in order to

  9. Simulation of Deep Water Renewal in Crater Lake, Oregon, USA under Current and Future Climate Conditions

    NASA Astrophysics Data System (ADS)

    Piccolroaz, S.; Wood, T. M.; Wherry, S.; Girdner, S.

    2015-12-01

    We applied a 1-dimensional lake model developed to simulate deep mixing related to thermobaric instabilities in temperate lakes to Crater Lake, a 590-m deep caldera lake in Oregon's Cascade Range known for its stunning deep blue color and extremely clear water, in order to determine the frequency of deep water renewal in future climate conditions. The lake model was calibrated with 6 years of water temperature profiles, and then simulated 10 years of validation data with an RMSE ranging from 0.81°C at 50 m depth to 0.04°C at 350-460 m depth. The simulated time series of heat content in the deep lake accurately captured extreme years characterized by weak and strong deep water renewal. The lake model uses wind speed and lake surface temperature (LST) as boundary conditions. LST projections under six climate scenarios from the CMIP5 intermodel comparison project (2 representative concentration pathways X 3 general circulation models) were evaluated with air2water, a simple lumped model that only requires daily values of downscaled air temperature. air2water was calibrated with data from 1993-2011, resulting in a RMSE between simulated and observed daily LST values of 0.68°C. All future climate scenarios project increased water temperature throughout the water column and a substantive reduction in the frequency of deepwater renewal events. The least extreme scenario (CNRM-CM5, RCP4.5) projects the frequency of deepwater renewal events to decrease from about 1 in 2 years in the present to about 1 in 3 years by 2100. The most extreme scenario (HadGEM2-ES, RCP8.5) projects the frequency of deepwater renewal events to be less than 1 in 7 years by 2100 and lake surface temperatures never cooling to less than 4°C after 2050. In all RCP4.5 simulations the temperature of the entire water column is greater than 4°C for increasing periods of time. In the RCP8.5 simulations, the temperature of the entire water column is greater than 4°C year round by the year 2060 (HadGEM2

  10. Carryover effects and climatic conditions influence the postfledging survival of greater sage-grouse

    USGS Publications Warehouse

    Blomberg, Erik J.; Sedinger, James S.; Gibson, Daniel; Coates, Peter S.; Casazza, Michael L.

    2014-01-01

    Prebreeding survival is an important life history component that affects both parental fitness and population persistence. In birds, prebreeding can be separated into pre- and postfledging periods; carryover effects from the prefledging period may influence postfledging survival. We investigated effects of body condition at fledging, and climatic variation, on postfledging survival of radio-marked greater sage-grouse (Centrocercus urophasianus) in the Great Basin Desert of the western United States. We hypothesized that body condition would influence postfledging survival as a carryover effect from the prefledging period, and we predicted that climatic variation may mediate this carryover effect or, alternatively, would act directly on survival during the postfledging period. Individual body condition had a strong positive effect on postfledging survival of juvenile females, suggesting carryover effects from the prefledging period. Females in the upper 25th percentile of body condition scores had a postfledging survival probability more than twice that (Φ = 0.51 ± 0.06 SE) of females in the bottom 25th percentile (Φ = 0.21 ± 0.05 SE). A similar effect could not be detected for males. We also found evidence for temperature and precipitation effects on monthly survival rates of both sexes. After controlling for site-level variation, postfledging survival was nearly twice as great following the coolest and wettest growing season (Φ = 0.77 ± 0.05 SE) compared with the hottest and driest growing season (Φ = 0.39 ± 0.05 SE). We found no relationships between individual body condition and temperature or precipitation, suggesting that carryover effects operated independently of background climatic variation. The temperature and precipitation effects we observed likely produced a direct effect on mortality risk during the postfledging period. Conservation actions that focus on improving prefledging habitat for sage-grouse may have indirect benefits

  11. Physiological changes in skin barrier function in relation to occlusion level, exposure time and climatic conditions.

    PubMed

    Schäfer, P; Bewick-Sonntag, C; Capri, M G; Berardesca, E

    2002-01-01

    Skin occlusion is a condition encountered with various articles as part of everyday life and resulting changes in skin barrier physiology often remain unnoticed. In the present study we aimed to understand the impact of absorbent feminine hygiene articles, one vapor-permeable and one vapor-impermeable, on skin hydration in response to exposure time and different environmental climatic conditions. Using a forearm model, volunteers were patched with moistened vapor-permeable and -impermeable articles in parallel for 1, 3, and 6 h and under different climatic conditions (i.e. 20 degrees C/30% relative humidity, 25 degrees C/50% relative humidity, 30 degrees C/ 75% relative humidity). The physiological changes in the skin barrier function were measured via skin hydration, evaporation of superficial water (skin surface water loss, SSWL) and relative humidity in the microclimate between skin and occlusive article (RH(mc)). The results show that skin hydration, SSWL, and RH(mc) under a vapor-permeable article are reduced versus the vapor-impermeable article for all exposure times at 25 degrees C and 50% relative humidity. SSWL and RH(mc) decrease from their 1-hour peak values with increasing exposure time, while skin hydration decreases only after 3 h of exposure. Lower environmental temperature (20 degrees C) and lower relative humidity (30%) have little impact on the reduction of SSWL and RH(mc,) but more so on the reduction of skin hydration. Higher temperature (30 degrees C) and higher relative humidity (75%) increase RH(mc) and skin hydration under both vapor-permeable and -impermeable articles while SSWL is reduced under the vapor-impermeable article under these conditions. In conclusion, vapor-permeability is the key factor for physiological changes in the barrier function of the skin under occlusion, exposure time and climatic conditions being modulating factors. These findings have been integrated into a model of skin hydration under occlusion in the context of

  12. Carryover effects and climatic conditions influence the postfledging survival of greater sage-grouse

    PubMed Central

    Blomberg, Erik J; Sedinger, James S; Gibson, Daniel; Coates, Peter S; Casazza, Michael L

    2014-01-01

    Prebreeding survival is an important life history component that affects both parental fitness and population persistence. In birds, prebreeding can be separated into pre- and postfledging periods; carryover effects from the prefledging period may influence postfledging survival. We investigated effects of body condition at fledging, and climatic variation, on postfledging survival of radio-marked greater sage-grouse (Centrocercus urophasianus) in the Great Basin Desert of the western United States. We hypothesized that body condition would influence postfledging survival as a carryover effect from the prefledging period, and we predicted that climatic variation may mediate this carryover effect or, alternatively, would act directly on survival during the postfledging period. Individual body condition had a strong positive effect on postfledging survival of juvenile females, suggesting carryover effects from the prefledging period. Females in the upper 25th percentile of body condition scores had a postfledging survival probability more than twice that (Φ = 0.51 ± 0.06 SE) of females in the bottom 25th percentile (Φ = 0.21 ± 0.05 SE). A similar effect could not be detected for males. We also found evidence for temperature and precipitation effects on monthly survival rates of both sexes. After controlling for site-level variation, postfledging survival was nearly twice as great following the coolest and wettest growing season (Φ = 0.77 ± 0.05 SE) compared with the hottest and driest growing season (Φ = 0.39 ± 0.05 SE). We found no relationships between individual body condition and temperature or precipitation, suggesting that carryover effects operated independently of background climatic variation. The temperature and precipitation effects we observed likely produced a direct effect on mortality risk during the postfledging period. Conservation actions that focus on improving prefledging habitat for sage-grouse may have indirect benefits

  13. Accounts from 19th-century Canadian Arctic explorers' logs reflect present climate conditions

    NASA Astrophysics Data System (ADS)

    Overland, James E.; Wood, Kevin

    The widely perceived failure of 19th-century expeditions to find and transit the Northwest Passage in the Canadian Arctic is often attributed to extraordinary cold climatic conditions associated with the “Little Ice Age” evident in proxy records. However, examination of 44 explorers' logs for the western Arctic from 1818 to 1910 reveals that climate indicators such as navigability, the distribution and thickness of annual sea ice, monthly surface air temperature, and the onset of melt and freeze were within the present range of variability.The quest for the Northwest Passage through the Canadian archipelago during the 19th century is frequently seen as a vain and tragic failure. Polar exploration during the Victorian era seems to us today to have been a costly exercise in heroic futility, which in many respects it was. This perspective has been reinforced since the 1970s, when paleoclimate reconstructions based on Arctic ice core stratigraphy appeared to confirm the existence of exceptionally cold conditions consistent with the period glaciologists had termed the “Little Ice Age” (Figure 1a), with temperatures more than one standard deviation colder relative to an early 20th-century mean [Koerner, 1977; Koerner and Fisher, 1990; Overpeck et al., 1998]. In recent years, the view of the Little Ice Age as a synchronous worldwide and prolonged cold epoch that ended with modern warming has been questioned [Bradley and Jones, 1993; Jones and Briffa, 2001 ;Ogilvie, 2001].

  14. The effect of water hyacinths for wastewater treatment under Cuban climatic conditions.

    PubMed

    Rodriguez, C; Jenssen, P D

    2005-01-01

    The purification capacity of systems using floating aquatic plants depend on the climatic conditions under which they are used. This study from Cuban conditions evaluate the effects of the organic loading rate, hydraulic loading rate and water depth on the purification capacity of water hyacinths, as well as the effect of some climatic variables on the kinetics of the treatment processes. The experimental system consisted of two consecutive tanks simulating a system of ponds in series. The water depths used were 0.5 m and 1.12 m. In the shallower system with shorter retention times and greater superficial organic loading higher removal efficiencies are obtained. With the data obtained, empirical relations were sought. From these correlations it is possible to determine the values for some parameters used in the design of aquatic treatment systems with water hyacinths. The results revealed a relationship between the purification capacity of the water hyacinth and its velocity of growth. The specific velocity of growth varied with the months of the year and was associated with the temperature and the solar radiation. A multiple correlation equation describing these relations was obtained. PMID:16114695

  15. Modeling of hydrologic conditions and solute movement in processed oil shale waste embankments under simulated climatic conditions

    SciTech Connect

    Turner, J.P.; Hasfurther, V.

    1992-05-04

    The scope of the research program and the continuation is to study interacting hydrologic, geotechnical, and chemical factors affecting the behavior and disposal of combusted processed oil shale. The research combines bench-scale testing with large scale research sufficient to describe commercial scale embankment behavior. The large scale approach was accomplished by establishing five lysimeters, each 7.3 [times] 3.0 [times] 3.0 m deep, filled with processed oil shale that has been retorted and combusted by the Lurgi-Ruhrgas (Lurgi) process. Approximately 400 tons of Lurgi processed oil shale waste was provided by Rio Blanco Oil Shale Co., Inc. (RBOSC) through a separate cooperative agreement with the University of Wyoming (UW) to carry out this study. Three of the lysimeters were established at the RBOSC Tract C-a in the Piceance Basin of Colorado. Two lysimeters were established in the Environmental Simulation Laboratory (ESL) at UW. The ESL was specifically designed and constructed so that a large range of climatic conditions could be physically applied to the processed oil shale which was filled in the lysimeter cells.

  16. Dissipation of El Niño-like climate conditions through Andean uplift

    NASA Astrophysics Data System (ADS)

    Feng, R.; Poulsen, C. J.

    2013-12-01

    Marine proxies of sea-surface temperature (SST) and thermocline depth have been used to infer an El Niño-like climate state during the Pliocene warm period (~4.5 to 3 Ma ago) consisting of a reduced tropical Pacific SST gradient and deeper thermocline depth in the eastern tropical Pacific. El Niño-like conditions dissipated around ~3 Ma, inaugurating the modern tropical climate. More recent studies extend the Pacific record of northeastern equatorial upwelling to the late Miocene (~13 Ma) and suggest long-term strengthening of the upwelling and shoaling of the thermocline since then. Shoaling is thought to have terminated the El Niño-like climate state by cooling eastern equatorial SSTs and activating the Bjerknes feedback. Late Cenozoic cooling is often proposed as the cause of thermocline shoaling. However, corroborating evidence is still needed given that CO2 levels are thought to have been fairly uniform between 12-5 Ma, and that coupled ocean-atmosphere models simulate a shallow eastern equatorial thermocline even under early Pliocene warmth. Here we propose an alternative cause for SST cooling at eastern tropical Pacific--Late Cenozoic uplift of the Andes. Although the timing and stages of the uplift of the Andes are uncertain, geological evidence suggests significant surface uplift on the order of 2 km since the late Miocene. The sensitivity of the equatorial Pacific climate to Andean uplift is explored using the NCAR Community Climate System Model (CCSM4). In our simulations, the ~2.5 km uplift of central Andes leads to reduction in eastern tropical Pacific SST by 1-2 °C and strengthening of the southeastern Pacific subtropical high and equatorial Easterlies, producing a pattern representative of a La Niña-like state. In addition, the thermocline shoals in the northeastern equatorial Pacific, in agreement with late Miocene marine records. Air-sea interactions are identified as the primary cause of this climate shift because: i) the thermocline adjusts

  17. Sensitivity of soil moisture initialization for decadal predictions under different regional climatic conditions in Europe

    NASA Astrophysics Data System (ADS)

    Khodayar, S.; Sehlinger, A.; Feldmann, H.; Kottmeier, C.

    2015-12-01

    The impact of soil initialization is investigated through perturbation simulations with the regional climate model COSMO-CLM. The focus of the investigation is to assess the sensitivity of simulated extreme periods, dry and wet, to soil moisture initialization in different climatic regions over Europe and to establish the necessary spin up time within the framework of decadal predictions for these regions. Sensitivity experiments consisted of a reference simulation from 1968 to 1999 and 5 simulations from 1972 to 1983. The Effective Drought Index (EDI) is used to select and quantify drought status in the reference run to establish the simulation time period for the sensitivity experiments. Different soil initialization procedures are investigated. The sensitivity of the decadal predictions to soil moisture initial conditions is investigated through the analysis of water cycle components' (WCC) variability. In an episodic time scale the local effects of soil moisture on the boundary-layer and the propagated effects on the large-scale dynamics are analysed. The results show: (a) COSMO-CLM reproduces the observed features of the drought index. (b) Soil moisture initialization exerts a relevant impact on WCC, e.g., precipitation distribution and intensity. (c) Regional characteristics strongly impact the response of the WCC. Precipitation and evapotranspiration deviations are larger for humid regions. (d) The initial soil conditions (wet/dry), the regional characteristics (humid/dry) and the annual period (wet/dry) play a key role in the time that soil needs to restore quasi-equilibrium and the impact on the atmospheric conditions. Humid areas, and for all regions, a humid initialization, exhibit shorter spin up times, also soil reacts more sensitive when initialised during dry periods. (e) The initial soil perturbation may markedly modify atmospheric pressure field, wind circulation systems and atmospheric water vapour distribution affecting atmospheric stability

  18. Climate and Population Health Vulnerabilities to Vector-Borne Diseases: Increasing Resilience Under Climate Change Conditions in Africa

    NASA Astrophysics Data System (ADS)

    Ceccato, P.; McDonald, K. C.; Podest, E.; De La Torre Juarez, M.; Kruczkiewicz, A.; Lessel, J.; Jensen, K.; Thomson, M. C.

    2014-12-01

    The International Research Institute for Climate and Society (IRI), the City University of New York (CUNY) and NASA Jet Propulsion Laboratory (JPL) in collaboration with NASA SERVIR are developing tools to monitor climate variables (precipitation, temperature, vegetation, water bodies, inundation) that help projects in Africa to increase resilience to climate change for vector-borne diseases (i.e. malaria, trypanosomiasis, leishmaniasis, and schistosomiasis). Through the development of new products to monitor precipitation, water bodies and inundation, IRI, CUNY and JPL provide tools and capacity building to research communities, ministries of health and World Health Organization in Africa to: 1) Develop research teams' ability to appropriately use climate data as part of their research 2) Enable research teams and ministries to integrate climate information into social and economic drivers of vulnerability and opportunities for adaptation to climate change 3) Inform better policies and programs for climate change adaptation. This oral presentation will demonstrate how IRI, CUNY, and JPL developed new products, tools and capacity building to achieve the three objectives mentioned above.

  19. The Milankovitch theory and climate sensitivity. I - Equilibrium climate model solutions for the present surface conditions. II - Interaction between the Northern Hemisphere ice sheets and the climate system

    NASA Technical Reports Server (NTRS)

    Neeman, Binyamin U.; Ohring, George; Joseph, Joachim H.

    1988-01-01

    A seasonal climate model was developed to test the climate sensitivity and, in particular, the Milankovitch (1941) theory. Four climate model versions were implemented to investigate the range of uncertainty in the parameterizations of three basic feedback mechanisms: the ice albedo-temperature, the outgoing long-wave radiation-temperature, and the eddy transport-meridional temperature gradient. It was found that the differences between the simulation of the present climate by the four versions were generally small, especially for annually averaged results. The climate model was also used to study the effect of growing/shrinking of a continental ice sheet, bedrock sinking/uplifting, and sea level changes on the climate system, taking also into account the feedback effects on the climate of the building of the ice caps.

  20. Modeling Floods under Climate Change Condition in Otava River, Czech Republic: A Time Scale Issue

    NASA Astrophysics Data System (ADS)

    Danhelka, J.; Krejci, J.; Vlasak, T.

    2009-04-01

    simulation differed by 10 to 36 % for different simulated scenarios including RC conditions. That supports the requirement of specific approach if assessing occurrence of rare events of return period longer than simulated period. REFERENCES Pretel, J. et al. (2008): Operating statement on Research Project: SP/1a6/108/07 - Precission of Current Estimates of Climate Change Impact on Water, Agriculture and Forestry and Adaptation Proposals, CHMI, Prague, Czech Republic, 2008 Semenov, M. A. (2008). Simulation of extreme weather events by a stochastic weather generator, Clim Res, 11:203-212

  1. About climate variabilitiy leading the hydric condition of the soil in the rainfed region of Argentina

    NASA Astrophysics Data System (ADS)

    Pántano, V. C.; Penalba, O. C.

    2013-05-01

    Extreme events of temperature and rainfall have a socio-economic impact in the rainfed agriculture production region in Argentina. The magnitude of the impact can be analyzed through the water balance which integrates the characteristics of the soil and climate conditions. Changes observed in climate variables during the last decades affected the components of the water balance. As a result, a displacement of the agriculture border towards the west was produced, improving the agricultural production of the region. The objective of this work is to analyze how the variability of rainfall and temperature leads the hydric condition of the soil, with special focus on extreme events. The hydric conditions of the soil (HC= Excess- Deficit) were estimated from the monthly water balance (Thornthwaite and Mather method, 1957), using monthly potential evapotranspiration (PET) and monthly accumulated rainfall (R) for 33 stations (period 1970-2006). Information of temperature and rainfall was provided by National Weather Service and the effective capacity of soil water was considered from Forte Lay and Spescha (2001). An agricultural extreme condition occurs when soil moisture and rainfall are inadequate or excessive for the development of the crops. In this study, we define an extreme event when the variable is less (greater) than its 20% and 10% (80% and 90%) percentile. In order to evaluate how sensitive is the HC to water and heat stress in the region, different conditional probabilities were evaluated. There is a weaker response of HC to extreme low PET while extreme low R leads high values of HC. However, this behavior is not always observed, especially in the western region where extreme high and low PET show a stronger influence over the HC. Finally, to analyze the temporal variability of extreme PET and R, leading hydric condition of the soil, the number of stations presenting extreme conditions was computed for each month. As an example, interesting results were

  2. Children's well-being at schools: Impact of climatic conditions and air pollution.

    PubMed

    Salthammer, Tunga; Uhde, Erik; Schripp, Tobias; Schieweck, Alexandra; Morawska, Lidia; Mazaheri, Mandana; Clifford, Sam; He, Congrong; Buonanno, Giorgio; Querol, Xavier; Viana, Mar; Kumar, Prashant

    2016-09-01

    Human civilization is currently facing two particular challenges: population growth with a strong trend towards urbanization and climate change. The latter is now no longer seriously questioned. The primary concern is to limit anthropogenic climate change and to adapt our societies to its effects. Schools are a key part of the structure of our societies. If future generations are to take control of the manifold global problems, we have to offer our children the best possible infrastructure for their education: not only in terms of the didactic concepts, but also with regard to the climatic conditions in the school environment. Between the ages of 6 and 19, children spend up to 8h a day in classrooms. The conditions are, however, often inacceptable and regardless of the geographic situation, all the current studies report similar problems: classrooms being too small for the high number of school children, poor ventilation concepts, considerable outdoor air pollution and strong sources of indoor air pollution. There have been discussions about a beneficial and healthy air quality in classrooms for many years now and in recent years extensive studies have been carried out worldwide. The problems have been clearly outlined on a scientific level and there are prudent and feasible concepts to improve the situation. The growing number of publications also highlights the importance of this subject. High carbon dioxide concentrations in classrooms, which indicate poor ventilation conditions, and the increasing particle matter in urban outdoor air have, in particular, been identified as primary causes of poor indoor air quality in schools. Despite this, the conditions in most schools continue to be in need of improvement. There are many reasons for this. In some cases, the local administrative bodies do not have the budgets required to address such concerns, in other cases regulations and laws stand in contradiction to the demands for better indoor air quality, and sometimes

  3. Global Agricultural Land Resources – A High Resolution Suitability Evaluation and Its Perspectives until 2100 under Climate Change Conditions

    PubMed Central

    Zabel, Florian; Putzenlechner, Birgitta; Mauser, Wolfram

    2014-01-01

    Changing natural conditions determine the land's suitability for agriculture. The growing demand for food, feed, fiber and bioenergy increases pressure on land and causes trade-offs between different uses of land and ecosystem services. Accordingly, an inventory is required on the changing potentially suitable areas for agriculture under changing climate conditions. We applied a fuzzy logic approach to compute global agricultural suitability to grow the 16 most important food and energy crops according to the climatic, soil and topographic conditions at a spatial resolution of 30 arc seconds. We present our results for current climate conditions (1981–2010), considering today's irrigated areas and separately investigate the suitability of densely forested as well as protected areas, in order to investigate their potentials for agriculture. The impact of climate change under SRES A1B conditions, as simulated by the global climate model ECHAM5, on agricultural suitability is shown by comparing the time-period 2071–2100 with 1981–2010. Our results show that climate change will expand suitable cropland by additionally 5.6 million km2, particularly in the Northern high latitudes (mainly in Canada, China and Russia). Most sensitive regions with decreasing suitability are found in the Global South, mainly in tropical regions, where also the suitability for multiple cropping decreases. PMID:25229634

  4. Window of Opportunity: The Climatic Conditions of the Lewis and Clark Expedition of 1804 1806.

    NASA Astrophysics Data System (ADS)

    Knapp, Paul A.

    2004-09-01

    Lewis and Clark's entry into to the American West in search of an inland Northwest Passage is considered among the greatest expeditions in American history. The Corps of Discovery were also lucky as their travels west of the 100th meridian occurred during a “window” of generally favorable climatic conditions. Use of reconstructed summer Palmer drought severity index (PDSI) values from 1700 1978 indicate that drought frequency at locations along the Lewis and Clark trail ranged from 4 to 12 yr and that the probability of encountering a drought either on the outbound or return trip approached 50% at some locations. Exact date comparisons of meteorological conditions during periods of extended encampment (i.e., 1 5 months) between 1804 06 with long-term records of nearby weather stations indicate that the Corps of Discovery avoided drought and traveled during a cooler and/or substantially wetter period than historical averages. Examination of reconstructed Southern Oscillation index (SOI) and Pacific decadal oscillation (PDO) values suggest wetter conditions prevailed in 1804 06 because of the co-occurrence of La Niña conditions during a cold PDO phase. Although the Corps of Discovery suffered hardships because of the wetter conditions, they avoided the more serious consequences of severe droughts that occurred in 1800 and 1808. Drought conditions along the semiarid and arid portions of the trail would have reduced forage yield for the game that were their principal source of food and increased their chances for starvation. Additionally, lower streamflow conditions along their principal navigation routes would have required greater effort and time to haul their supplies to the Continental Divide, perhaps delaying their expedition by a year.

  5. Regional Arctic sea ice variations as predictor for winter climate conditions

    NASA Astrophysics Data System (ADS)

    Koenigk, Torben; Caian, Mihaela; Nikulin, Grigory; Schimanke, Semjon

    2016-01-01

    Seasonal prediction skill of winter mid and high northern latitudes climate from sea ice variations in eight different Arctic regions is analyzed using detrended ERA-interim data and satellite sea ice data for the period 1980-2013. We find significant correlations between ice areas in both September and November and winter sea level pressure, air temperature and precipitation. The prediction skill is improved when using November sea ice conditions as predictor compared to September. This is particularly true for predicting winter NAO-like patterns and blocking situations in the Euro-Atlantic area. We find that sea ice variations in Barents Sea seem to be most important for the sign of the following winter NAO—negative after low ice—but amplitude and extension of the patterns are modulated by Greenland and Labrador Seas ice areas. November ice variability in the Greenland Sea provides the best prediction skill for central and western European temperature and ice variations in the Laptev/East Siberian Seas have the largest impact on the blocking number in the Euro-Atlantic region. Over North America, prediction skill is largest using September ice areas from the Pacific Arctic sector as predictor. Composite analyses of high and low regional autumn ice conditions reveal that the atmospheric response is not entirely linear suggesting changing predictive skill dependent on sign and amplitude of the anomaly. The results confirm the importance of realistic sea ice initial conditions for seasonal forecasts. However, correlations do seldom exceed 0.6 indicating that Arctic sea ice variations can only explain a part of winter climate variations in northern mid and high latitudes.

  6. CLIMATE CONDITIONS AFFECTING THE WITHIN-PLANT SPREAD OF BROAD MITES ON AZALEA.

    PubMed

    Mechant, E; Pauwels, E; Gobin, B

    2014-01-01

    The broad mite Polyphagotarsonemus latus (Banks) is considered a major pest in potted azalea, Flanders' flagship ornamental crop of Rhododendron simsii hybrids. In addition to severe economic damage, the broad mite is dreaded for its increasing resistance to acaricides. Due to restrictions in the use of broad spectrum acaricides, Belgian azalea growers are left with only three compounds, belonging to two mode of action groups and restricted in their number of applications, for broad mite control: abamectin, milbemectin and pyrethrin. Although P. latus can be controlled with predatory mites, the high cost of this system makes it (not yet) feasible for integration into standard azalea pest management systems. Hence, a maximum efficacy of treatments with available compounds is essential. Because abamectin, milbemectin and pyrethrin are contact acaricides with limited trans laminar flow, only broad mites located on shoot tips of azalea plants will be controlled after spraying. Consequently, the efficacy of chemical treatments is influenced by the location and spread of P. latus on the plant. Unfortunately, little is known on broad mites' within-plant spread or how it is affected by climatic conditions like temperature and relative humidity. Therefore, experiments were set up to verify whether climate conditions have an effect on the location and migration of broad mites on azalea. Broad mite infected azalea plants were placed in standard growth chambers under different temperature (T:2.5-25°C) and relative humidity (RH:55-80%) treatments. Within-plant spread was determined by counting mites on the shoot tips and inner leaves of azalea plants. Results indicate that temperature and relative humidity have no significant effect on the within-plant spread of P. latus. To formulate recommendations for optimal spray conditions to maximize the efficacy of broad mite control with acaricides, further experiments on the effect of light intensity and rain are scheduled. PMID

  7. Can phenological models predict tree phenology accurately under climate change conditions?

    NASA Astrophysics Data System (ADS)

    Chuine, Isabelle; Bonhomme, Marc; Legave, Jean Michel; García de Cortázar-Atauri, Inaki; Charrier, Guillaume; Lacointe, André; Améglio, Thierry

    2014-05-01

    The onset of the growing season of trees has been globally earlier by 2.3 days/decade during the last 50 years because of global warming and this trend is predicted to continue according to climate forecast. The effect of temperature on plant phenology is however not linear because temperature has a dual effect on bud development. On one hand, low temperatures are necessary to break bud dormancy, and on the other hand higher temperatures are necessary to promote bud cells growth afterwards. Increasing phenological changes in temperate woody species have strong impacts on forest trees distribution and productivity, as well as crops cultivation areas. Accurate predictions of trees phenology are therefore a prerequisite to understand and foresee the impacts of climate change on forests and agrosystems. Different process-based models have been developed in the last two decades to predict the date of budburst or flowering of woody species. They are two main families: (1) one-phase models which consider only the ecodormancy phase and make the assumption that endodormancy is always broken before adequate climatic conditions for cell growth occur; and (2) two-phase models which consider both the endodormancy and ecodormancy phases and predict a date of dormancy break which varies from year to year. So far, one-phase models have been able to predict accurately tree bud break and flowering under historical climate. However, because they do not consider what happens prior to ecodormancy, and especially the possible negative effect of winter temperature warming on dormancy break, it seems unlikely that they can provide accurate predictions in future climate conditions. It is indeed well known that a lack of low temperature results in abnormal pattern of bud break and development in temperate fruit trees. An accurate modelling of the dormancy break date has thus become a major issue in phenology modelling. Two-phases phenological models predict that global warming should delay

  8. Assessing the impacts of climate change in Mediterranean catchments under conditions of data scarcity

    NASA Astrophysics Data System (ADS)

    Meyer, Swen; Ludwig, Ralf

    2013-04-01

    According to current climate projections, Mediterranean countries are at high risk for an even pronounced susceptibility to changes in the hydrological budget and extremes. While there is scientific consensus that climate induced changes on the hydrology of Mediterranean regions are presently occurring and are projected to amplify in the future, very little knowledge is available about the quantification of these changes, which is hampered by a lack of suitable and cost effective hydrological monitoring and modeling systems. The European FP7-project CLIMB is aiming to analyze climate induced changes on the hydrology of the Mediterranean Basins by investigating 7 test sites located in the countries Italy, France, Turkey, Tunisia, Gaza and Egypt. CLIMB employs a combination of novel geophysical field monitoring concepts, remote sensing techniques and integrated hydrologic modeling to improve process descriptions and understanding and to quantify existing uncertainties in climate change impact analysis. The Rio Mannu Basin, located in Sardinia; Italy, is one test site of the CLIMB project. The catchment has a size of 472.5 km2, it ranges from 62 to 946 meters in elevation, at mean annual temperatures of 16°C and precipitation of about 700 mm, the annual runoff volume is about 200 mm. The physically based Water Simulation Model WaSiM Vers. 2 (Schulla & Jasper (1999)) was setup to model current and projected future hydrological conditions. The availability of measured meteorological and hydrological data is poor as common to many Mediterranean catchments. The lack of available measured input data hampers the calibration of the model setup and the validation of model outputs. State of the art remote sensing techniques and field measuring techniques were applied to improve the quality of hydrological input parameters. In a field campaign about 250 soil samples were collected and lab-analyzed. Different geostatistical regionalization methods were tested to improve the

  9. Remote sensing of interannual boreal forest NDVI in relation to climatic conditions in interior Alaska

    NASA Astrophysics Data System (ADS)

    Verbyla, David

    2015-12-01

    Climate has warmed substantially in interior Alaska and several remote sensing studies have documented a decadal-scale decline in the normalized difference vegetation index (NDVI) termed a ‘browning trend’. Reduced summer soil moisture due to changing climatic factors such as earlier springs, less snowpack, and summer drought may reduce boreal productivity and NDVI. However, the relative importance of these climatic factors is poorly understood in boreal interior Alaska. In this study, I used the remotely sensed peak summer NDVI as an index of boreal productivity at 250 m pixel size from 2000 to 2014. Maximum summer NDVI was related to last day of spring snow, early spring snow water equivalent (SWE), and a summer moisture index. There was no significant correlation between early spring SWE and peak summer NDVI. There was a significant correlation between the last day of spring snow and peak summer NDVI, but only for a few higher elevation stations. This was likely due to snowmelt occurring later at higher elevations, thus having a greater effect on summer soil moisture relative to lower elevation sites. For most of boreal interior Alaska, summer drought was likely the dominant control on peak summer NDVI and this effect may persist for several years. Peak summer NDVI declined at all 26 stations after the 2004 drought, and the decline persisted for 2 years at all stations. Due to the shallow rooting zone of most boreal plants, even cool and moist sites at lower elevations are likely vulnerable to drought. For example the peak summer NDVI response following the 2004 drought was similar for adjacent cold and warm watershed basins. Thus, if frequent and severe summer droughts continue, moisture stress effects are likely to be widespread and prolonged throughout most of interior boreal Alaska, including relatively cool, moist sites regardless of spring snowpack conditions or spring phenology.

  10. Performance Analysis of Air-to-Water Heat Pump in Latvian Climate Conditions

    NASA Astrophysics Data System (ADS)

    Kazjonovs, Janis; Sipkevics, Andrejs; Jakovics, Andris; Dancigs, Andris; Bajare, Diana; Dancigs, Leonards

    2014-12-01

    Strategy of the European Union in efficient energy usage demands to have a higher proportion of renewable energy in the energy market. Since heat pumps are considered to be one of the most efficient heating and cooling systems, they will play an important role in the energy consumption reduction in buildings aimed to meet the target of nearly zero energy buildings set out in the EU Directive 2010/31/EU. Unfortunately, the declared heat pump Coefficient of Performance (COP) corresponds to a certain outdoor temperature (+7 °C), therefore different climate conditions, building characteristics and settings result in different COP values during the year. The aim of this research is to investigate the Seasonal Performance factor (SPF) values of air-to-water heat pump which better characterize the effectiveness of heat pump in a longer selected period of time, especially during the winter season, in different types of residential buildings in Latvian climate conditions. Latvia has four pronounced seasons of near-equal length. Winter starts in mid-December and lasts until mid-March. Latvia is characterized by cold, maritime climate (duration of the average heating period being 203 days, the average outdoor air temperature during the heating period being 0.0 °C, the coldest five-day average temperature being -20.7 °C, the average annual air temperature being +6.2 °C, the daily average relative humidity being 79 %). The first part of this research consists of operational air-towater heat pump energy performance monitoring in different residential buildings during the winter season. The second part of the research takes place under natural conditions in an experimental construction stand which is located in an urban environment in Riga, Latvia. The inner area of this test stand, where air-to-water heat pump performance is analyzed, is 9 m2. The ceiling height is 3 m, all external wall constructions (U = 0.16 W/(m2K)) have ventilated facades. To calculate SPF, the

  11. Controls of soil hydraulic characteristics on modeling groundwater recharge under different climatic conditions

    NASA Astrophysics Data System (ADS)

    Wang, Tiejun; Franz, Trenton E.; Zlotnik, Vitaly A.

    2015-02-01

    To meet the challenge of estimating spatially varying groundwater recharge (GR), increasing attention has been given to the use of vadose zone models (VZMs). However, the application of this approach is usually constrained by the lack of field soil hydraulic characteristics (SHCs) required by VZMs. To tackle this issue, SHCs based on the van Genuchten or Brooks-Corey model are generally estimated by pedotransfer functions or taken from texture based class averages. With the increasing use of this method, it is important to elucidate the controls of SHCs on computing GR mostly due to the high nonlinearity of the models. In this study, it is hypothesized that the nonlinear controls of SHCs on computing GR would vary with climatic conditions. To test this hypothesis, a widely used VZM along with two SHCs datasets for sand and loamy sand is used to compute GR at four sites in the continental Unites States with a significant gradient of precipitation (P). The simulation results show that the distribution patterns of mean annual GR ratios (GR ‾ / P ‾ , where GR ‾ and P ‾ are mean annual GR and P, respectively) vary considerably across the sites, largely depending on soil texture and climatic conditions at each site. It is found that GR ‾ / P ‾ is mainly controlled by the shape factor n in the van Genuchten model and the nonlinear effect of n on GR ‾ / P ‾ varies with climatic conditions. Specifically, for both soil textures, the variability in GR ‾ / P ‾ is smallest at the Andrews Forest with the highest P ‾ (191.3 cm/year) and GR ‾ / P ‾ is least sensitive to n; whereas, the variability in GR ‾ / P ‾ at the Konza Prairie (P ‾ = 84.2 cm/year) is the largest and GR ‾ / P ‾ is most sensitive to n. With further decreasing P ‾ , the nonlinear effect of n weakens at the Barta Brothers (P ‾ = 57.3 cm/year) and Sevilleta (P ‾ = 20.3 cm/year), leading to smaller GR ‾ / P ‾ variability at those two sites than at the Konza Prairie. The

  12. Seasonal Prediction of Hydro-Climatic Extremes in the Greater Horn of Africa Under Evolving Climate Conditions to Support Adaptation Strategies

    NASA Astrophysics Data System (ADS)

    Tadesse, T.; Zaitchik, B. F.; Habib, S.; Funk, C. C.; Senay, G. B.; Dinku, T.; Policelli, F. S.; Block, P.; Baigorria, G. A.; Beyene, S.; Wardlow, B.; Hayes, M. J.

    2014-12-01

    The development of effective strategies to adapt to changes in the character of droughts and floods in Africa will rely on improved seasonal prediction systems that are robust to an evolving climate baseline and can be integrated into disaster preparedness and response. Many efforts have been made to build models to improve seasonal forecasts in the Greater Horn of Africa region (GHA) using satellite and climate data, but these efforts and models must be improved and translated into future conditions under evolving climate conditions. This has considerable social significance, but is challenged by the nature of climate predictability and the adaptability of coupled natural and human systems facing exposure to climate extremes. To address these issues, work is in progress under a project funded by NASA. The objectives of the project include: 1) Characterize and explain large-scale drivers in the ocean-atmosphere-land system associated with years of extreme flood or drought in the GHA. 2) Evaluate the performance of state-of-the-art seasonal forecast methods for prediction of decision-relevant metrics of hydrologic extremes. 3) Apply seasonal forecast systems to prediction of socially relevant impacts on crops, flood risk, and economic outcomes, and assess the value of these predictions to decision makers. 4) Evaluate the robustness of seasonal prediction systems to evolving climate conditions. The National Drought Mitigation Center (University of Nebraska-Lincoln, USA) is leading this project in collaboration with the USGS, Johns Hopkins University, University of Wisconsin-Madison, the International Research Institute for Climate and Society, NASA, and GHA local experts. The project is also designed to have active engagement of end users in various sectors, university researchers, and extension agents in GHA through workshops and/or webinars. This project is expected improve and implement new and existing climate- and remote sensing-based agricultural

  13. Paradoxical cold conditions during the medieval climate anomaly in the Western Arctic

    PubMed Central

    Jomelli, Vincent; Lane, Timothy; Favier, Vincent; Masson-Delmotte, Valerie; Swingedouw, Didier; Rinterknecht, Vincent; Schimmelpfennig, Irene; Brunstein, Daniel; Verfaillie, Deborah; Adamson, Kathryn; Leanni, Laëtitia; Mokadem, Fatima; Aumaître, Georges; Bourlès, Didier L.; Keddadouche, Karim

    2016-01-01

    In the Northern Hemisphere, most mountain glaciers experienced their largest extent in the last millennium during the Little Ice Age (1450 to 1850 CE, LIA), a period marked by colder hemispheric temperatures than the Medieval Climate Anomaly (950 to 1250 CE, MCA), a period which coincided with glacier retreat. Here, we present a new moraine chronology based on 36Cl surface exposure dating from Lyngmarksbræen glacier, West Greenland. Consistent with other glaciers in the western Arctic, Lyngmarksbræen glacier experienced several advances during the last millennium, the first one at the end of the MCA, in ~1200 CE, was of similar amplitude to two other advances during the LIA. In the absence of any significant changes in accumulation records from South Greenland ice cores, we attribute this expansion to multi-decadal summer cooling likely driven by volcanic and/or solar forcing, and associated regional sea-ice feedbacks. Such regional multi-decadal cold conditions at the end of the MCA are neither resolved in temperature reconstructions from other parts of the Northern Hemisphere, nor captured in last millennium climate simulations. PMID:27609585

  14. Adapting SOYGRO V5.42 for prediction under climate change conditions

    SciTech Connect

    Pickering, N.B.; Jones, J.W.; Boote, K.J.

    1995-12-31

    In some studies of the impacts of climate change on global crop production, crop growth models were empirically adapted to improve their response to increased CO{sub 2} concentration and air temperature. This chapter evaluates the empirical adaptations of the photosynthesis and evapotranspiration (ET) algorithms used in the soybean [Glycine max (L.) Merr.] model, SOYGRO V5.42, by comparing it with a new model that includes mechanistic approaches for these two processes. The new evapotranspiration-photosynthesis sub-model (ETPHOT) uses a hedgerow light interception algorithm, a C{sub 3}-leaf biochemical photosynthesis submodel, and predicts canopy ET and temperatures using a three-zone energy balance. ETPHOT uses daily weather data, has an internal hourly time step, and sums hourly predictions to obtain daily gross photosynthesis and ET. The empirical ET and photosynthesis curves included in SOYGRO V5.42 for climate change prediction were similar to those predicted by the ETPHOT model. Under extreme conditions that promote high leaf temperatures, like in the humid tropics. SOYGRO V5.42 overestimated daily gross photosynthesis response to CO{sub 2} compared with the ETPHOT model. SOYGRO V5.42 also slightly overestimated daily gross photosynthesis at intermediate air temperatures and ambient CO{sub 2} concentrations. 80 refs., 12 figs.

  15. Assessing the Land-Ocean Interaction under Extreme Climate Change Condition - a Modeling Approach

    NASA Astrophysics Data System (ADS)

    Yang, Z.; Wang, T.; Leung, R.; Balaguru, K.; Hibbard, K. A.

    2011-12-01

    Many modeling applications, at global and regional scales, have demonstrated that numerical models are useful tools to quantify the uncertainty and the interactions between natural physical and biogeochemical processes and human activities in coastal regions. A regional integrated assessment modeling framework to investigate the interactions of agriculture and land use, coastal ecological issues, energy supply and effects of climate changes is under development by Pacific Northwest National Laboratory (PNNL), with specific application to the Gulf of Mexico. The Gulf is vulnerable to the direct impacts of climate changes, such as sea level rise, hurricane-induced storm surge and extreme floods due to high precipitation and river run-off. This presentation will focus on the coastal modeling aspect of this integrated modeling approach. An unstructured-grid finite volume coastal ocean model, which has the capability of simulating coastal circulation, wave and storm surges, sediment transport and biogeochemical processes, is applied to simulate hurricane storm surges and extreme flood events in the coastal region of Gulf of Mexico. Specifically, storm surge along the US Southeast coasts and freshwater plume in the Mississippi Delta were simulated and compared to observations. Numerical sensitivity studies with boundary conditions and forcing indicated the urgent need of a real observation network as well as the importance of accurate model predictions at regional scales to drive the model at smaller scales. The implication of natural pressures, such as storm surge and flooding to biogeochemical processes and marine ecosystem will be discussed.

  16. Kinetically limited weathering at low denudation rates in semiarid climatic conditions

    NASA Astrophysics Data System (ADS)

    Schoonejans, Jérôme; Vanacker, Veerle; Opfergelt, Sophie; Ameijeiras-Mariño, Yolanda; Christl, Marcus

    2016-02-01

    Biogeochemical cycling within the Critical Zone depends on the interactions between minerals and fluids controlling chemical weathering and physical erosion rates. In this study, we explore the role of water availability in controlling soil chemical weathering in semiarid climatic conditions. Weathering rates and intensities were evaluated for nine soil profiles located on convex ridge crests of three mountain ranges in the Spanish Betic Cordillera. We combine a geochemical mass balance with 10Be cosmogenic nuclides to constrain chemical weathering intensities and long-term denudation rates. As such, this study presents new data on chemical weathering and 10Be-derived denudation for understudied semiarid climate systems. In the Betic Cordillera, chemical weathering intensities are relatively low (~5 to 30% of the total denudation of the soil) and negatively correlated with the magnitude of the water deficit in soils. Chemical mass losses are inversely related to denudation rates (14-109 mm/kyr) and positively to soil thickness (14-58 cm); these results are consistent with kinetic limitation of chemical weathering rates. A worldwide compilation of chemical weathering data suggests that soil water balance may regulate the coupling between chemical weathering and physical erosion by modulating soil solute fluxes. Therefore, future landscape evolution models that seek to link chemical weathering and physical erosion should include soil water flux as an essential driver of weathering.

  17. Paradoxical cold conditions during the medieval climate anomaly in the Western Arctic.

    PubMed

    Jomelli, Vincent; Lane, Timothy; Favier, Vincent; Masson-Delmotte, Valerie; Swingedouw, Didier; Rinterknecht, Vincent; Schimmelpfennig, Irene; Brunstein, Daniel; Verfaillie, Deborah; Adamson, Kathryn; Leanni, Laëtitia; Mokadem, Fatima

    2016-01-01

    In the Northern Hemisphere, most mountain glaciers experienced their largest extent in the last millennium during the Little Ice Age (1450 to 1850 CE, LIA), a period marked by colder hemispheric temperatures than the Medieval Climate Anomaly (950 to 1250 CE, MCA), a period which coincided with glacier retreat. Here, we present a new moraine chronology based on (36)Cl surface exposure dating from Lyngmarksbræen glacier, West Greenland. Consistent with other glaciers in the western Arctic, Lyngmarksbræen glacier experienced several advances during the last millennium, the first one at the end of the MCA, in ~1200 CE, was of similar amplitude to two other advances during the LIA. In the absence of any significant changes in accumulation records from South Greenland ice cores, we attribute this expansion to multi-decadal summer cooling likely driven by volcanic and/or solar forcing, and associated regional sea-ice feedbacks. Such regional multi-decadal cold conditions at the end of the MCA are neither resolved in temperature reconstructions from other parts of the Northern Hemisphere, nor captured in last millennium climate simulations. PMID:27609585

  18. Monitoring Thermal Performance of Hollow Bricks with Different Cavity Fillers in Difference Climate Conditions

    NASA Astrophysics Data System (ADS)

    Pavlík, Zbyšek; Jerman, Miloš; Fořt, Jan; Černý, Robert

    2015-03-01

    Hollow brick blocks have found widespread use in the building industry during the last decades. The increasing requirements to the thermal insulation properties of building envelopes given by the national standards in Europe led the brick producers to reduce the production of common solid bricks. Brick blocks with more or less complex systems of internal cavities replaced the traditional bricks and became dominant on the building ceramics market. However, contrary to the solid bricks where the thermal conductivity can easily be measured by standard methods, the complex geometry of hollow brick blocks makes the application of common techniques impossible. In this paper, a steady-state technique utilizing a system of two climatic chambers separated by a connecting tunnel for sample positioning is used for the determination of the thermal conductivity, thermal resistance, and thermal transmittance ( U value) of hollow bricks with the cavities filled by air, two different types of mineral wool, polystyrene balls, and foam polyurethane. The particular brick block is provided with the necessary temperature- and heat-flux sensors and thermally insulated in the tunnel. In the climatic chambers, different temperatures are set. After steady-state conditions are established in the measuring system, the effective thermal properties of the brick block are calculated using the measured data. Experimental results show that the best results are achieved with hydrophilic mineral wool as a cavity filler; the worst performance exhibits the brick block with air-filled cavities.

  19. Effects of initial conditions uncertainty on regional climate variability: An analysis using a low-resolution CESM ensemble

    NASA Astrophysics Data System (ADS)

    Sriver, Ryan L.; Forest, Chris E.; Keller, Klaus

    2015-07-01

    The uncertainties surrounding the initial conditions in Earth system models can considerably influence interpretations about climate trends and variability. Here we present results from a new climate change ensemble experiment using the Community Earth System Model (CESM) to analyze the effect of internal variability on regional climate variables that are relevant for decision making. Each simulation is initialized from a unique and dynamically consistent model state sampled from a ~10,000 year fully coupled equilibrium simulation, which captures the internal unforced variability of the coupled Earth system. We find that internal variability has a sizeable contribution to the modeled ranges of temperature and precipitation. The effects increase for more localized regions. The ensemble exhibits skill in simulating key regional climate processes relevant to decision makers, such as seasonal temperature variability and extremes. The presented ensemble framework and results can provide useful resources for uncertainty quantification, integrated assessment, and climate risk management.

  20. Simulation of in-stream water quality on global scale under changing climate and anthropogenic conditions

    NASA Astrophysics Data System (ADS)

    Voss, Anja; Bärlund, Ilona; Punzet, Manuel; Williams, Richard; Teichert, Ellen; Malve, Olli; Voß, Frank

    2010-05-01

    Although catchment scale modelling of water and solute transport and transformations is a widely used technique to study pollution pathways and effects of natural changes, policies and mitigation measures there are only a few examples of global water quality modelling. This work will provide a description of the new continental-scale model of water quality WorldQual and the analysis of model simulations under changed climate and anthropogenic conditions with respect to changes in diffuse and point loading as well as surface water quality. BOD is used as an indicator of the level of organic pollution and its oxygen-depleting potential, and for the overall health of aquatic ecosystems. The first application of this new water quality model is to river systems of Europe. The model itself is being developed as part of the EU-funded SCENES Project which has the principal goal of developing new scenarios of the future of freshwater resources in Europe. The aim of the model is to determine chemical fluxes in different pathways combining analysis of water quantity with water quality. Simple equations, consistent with the availability of data on the continental scale, are used to simulate the response of in-stream BOD concentrations to diffuse and anthropogenic point loadings as well as flow dilution. Point sources are divided into manufacturing, domestic and urban loadings, whereas diffuse loadings come from scattered settlements, agricultural input (for instance livestock farming), and also from natural background sources. The model is tested against measured longitudinal gradients and time series data at specific river locations with different loading characteristics like the Thames that is driven by domestic loading and Ebro with relative high share of diffuse loading. With scenario studies the influence of climate and anthropogenic changes on European water resources shall be investigated with the following questions: 1. What percentage of river systems will have

  1. Climatic and environmental conditions favoring the crossing of the Carpathians by early Neolithic populations

    NASA Astrophysics Data System (ADS)

    Perşoiu, Ioana; Perşoiu, Aurel

    2015-04-01

    The study of the origin and spread of Neolithic has been the subject of heated debate since the early studies of Childe (1942). To what extent the dispersal process was influenced by environmental factors is still debated, one of the issues being whether climatic conditions influencing agricultural practices, could have influenced the dispersal route, "blocking" some of the Neolithic societies in front of ecological barriers. Data from Neolithic sites in SE Europe shows that a continuous stream of people and cultures flowed through the Danube's Iron Gates towards Central Europe, while in the eastern part of Europe this process was delayed, people and cultures "moving" around the Carpathians and crossing them with a delay of ca. 1000 years. One of the possible avenues for this crossing is the floodplain of Someşu Mic River (Transylvanian depression), home to the oldest (~8500 cal. BP) Neolithic settlement in Romania. In this paper, we review the climatic and environmental changes that affected the region at the time of Neolithic dispersal. Pollen and stable isotopes in cave ice indicate an early Holocene rapid warming during summer months, peaking around 7 ka cal. BP; and a delayed warming for autumn and winter months, peaking at 5 ka cal. BP, both followed by a continuous cooling trend towards the present. Someşu Mic River developed and maintained a narrow sinuous channel during the Holocene, with local development of meanders and anabranches, in response to both climatic and geologic controlling factors. Archaeological finds in the floodplain and the lower terraces suggest that human societies in the region responded in sensitive manner to these climatic and environmental changes. During warm and dry periods, with low fluvial activity, the number of settlements increased in the floodplain's perimeter, while during the short cold and humid periods, the number of settlements rapidly increased on the lower terraces and on the valley slopes, disappearing from the

  2. Hydraulics of sub-superficial flow constructed wetlands in semi arid climate conditions.

    PubMed

    Ranieri, E

    2003-01-01

    This paper reports the evaluation of the hydraulics of two constructed wetland (cw(s)) plants located in Apulia (the South Eastern Italy region characterized by semi arid climate conditions). These fields were planted with Phragmites australis hydrophytes and are supplied with local secondary wastewater municipal treatment plant effluent. Each plant--Kickuth Root-Zone method based--covers an area of approx. 2,000 m2. The evapotranspiration phenomenon has been evaluated within perforated tubes fixed to the field bottom and very high values--up to 40 mm/d--were found. Hydraulic conductivity has been evaluated by in situ measurements at different field points. Hydraulic gradients and the piezometric curve within the field are also reported. PMID:12793661

  3. Present and future assessment of growing degree days over selected Greek areas with different climate conditions

    NASA Astrophysics Data System (ADS)

    Pattanaik, D. R.; Mohapatra, M.; Srivastava, A. K.; Kumar, Arun

    2016-06-01

    The determination of heat requirements in the first developing phases of plants has been expressed as Growing Degree Days (GDD). The current study focuses on three selected study areas in Greece that are characterised by different climatic conditions due to their location and aims to assess the future variation and spatial distribution of Growing Degree Days (GDD) and how these can affect the main cultivations in the study areas. Future temperature data were obtained and analysed by the ENSEMBLES project. The analysis was performed for the future periods 2021-2050 and 2071-2100 with the A1B and B1 scenarios. Spatial distribution was performed using a combination of dynamical and statistical downscaling technique through ArcGIS 10.2.1. The results indicated that for all the future periods and scenarios, the GDD are expected to increase. Furthermore, the increase in the Sperchios River basin will be the highest, followed by the Ardas and the Geropotamos River basins. Moreover, the cultivation period will be shifted from April-October to April-September which will have social, economical and environmental benefits. Additionally, the spatial distribution indicated that in the upcoming years the existing cultivations can find favourable conditions and can be expanded in mountainous areas as well. On the other hand, due to the rough topography that exists in the study areas, the wide expansion of the existing cultivations into higher altitudes is unaffordable. Nevertheless, new more profitable cultivations can be introduced which can find propitious conditions in terms of GDD.

  4. Bulk volumetric liquid water content in a seasonal snowpack: modeling its dynamics in different climatic conditions

    NASA Astrophysics Data System (ADS)

    Avanzi, Francesco; Yamaguchi, Satoru; Hirashima, Hiroyuki; De Michele, Carlo

    2015-12-01

    We focus on the dynamics of volumetric liquid water content in seasonal snow covers. This is a key variable describing the fate of snowpacks during the melting season. However, its measurement and/or prediction by means of models at high spatial and temporal resolutions is still difficult due to both practical and theoretical reasons. To overcome these limitations in operational applications, we test the capability of a one-dimensional model to predict the dynamics of bulk volumetric liquid water content during a snow season. Multi-year data collected in three experimental sites in Japan are used as an evaluation. These sites are subjected to different climatic conditions. The model requires the calibration of one or two parameters, according to the degree of detail used. Either a simple temperature-index or a coupled melt-freeze temperature-index approach are considered to predict melting and/or melt-freeze dynamics of liquid water. Results show that, if melt-freeze dynamics are modeled, median absolute differences between data and predictions are consistently lower than 1 vol% at the sites where data of liquid water content are available. In addition, we find also that the model predicts correctly a dry condition in 80% of the observed cases at a site where calibration data are scarce. At the same site, observed isothermal conditions of the snow cover at 0 °C correspond to predictions of bulk volumetric liquid water content that are greater than 0.

  5. Effects of flow scarcity on leaf-litter processing under oceanic climate conditions in calcareous streams.

    PubMed

    Martínez, Aingeru; Pérez, Javier; Molinero, Jon; Sagarduy, Mikel; Pozo, Jesús

    2015-01-15

    Although temporary streams represent a high proportion of the total number and length of running waters, historically the study of intermittent streams has received less attention than that of perennial ones. The goal of the present study was to assess the effects of flow cessation on litter decomposition in calcareous streams under oceanic climate conditions. For this, leaf litter of alder was incubated in four streams (S1, S2, S3 and S4) with different flow regimes (S3 and S4 with zero-flow periods) from northern Spain. To distinguish the relative importance and contribution of decomposers and detritivores, fine- and coarse-mesh litter bags were used. We determined processing rates, leaf-C, -N and -P concentrations, invertebrate colonization in coarse bags and benthic invertebrates. Decomposition rates in fine bags were similar among streams. In coarse bags, only one of the intermittent streams, S4, showed a lower rate than that in the other ones as a consequence of lower invertebrate colonization. The material incubated in fine bags presented higher leaf-N and -P concentrations than those in the coarse ones, except in S4, pointing out that the decomposition in this stream was driven mainly by microorganisms. Benthic macroinvertebrate and shredder density and biomass were lower in intermittent streams than those in perennial ones. However, the bags in S3 presented a greater amount of total macroinvertebrates and shredders comparing with the benthos. The most suitable explanation is that the fauna find a food substrate in bags less affected by calcite precipitation, which is common in the streambed at this site. Decomposition rate in coarse bags was positively related to associated shredder biomass. Thus, droughts in streams under oceanic climate conditions affect mainly the macroinvertebrate detritivore activity, although macroinvertebrates may show distinct behavior imposed by the physicochemical properties of water, mainly travertine precipitation, which can

  6. Investigation of Regional Drivers for Discharge Variability in the Blue Nile Basin under Climate Change Conditions

    NASA Astrophysics Data System (ADS)

    Tecklenburg, J.; Hattermann, F. F.; Liersch, S.

    2012-04-01

    A discharge time series is the result of complex and interacting processes. Important for the runoff variability are catchment characteristics like the basin size and shape, gradient of altitude and exposition as well as micro- and macroclimatic conditions. The discharge dynamic of the Blue Nile is predominantly controlled by the monsoon variability. Due to the steep gradients in the Ethiopian highlands, the surface flow component represents the main fraction of the total discharge. The composition of discharge and the resulting time response of river runoff is further a function of subsurface retention and surface roughness. Thus, the soil surface characteristics and thereby the land use are main factors controlling formation of local water availability in the Upper Blue Nile basin. During the last 30 years the continual transformation of forest and grassland to cropland reduced the total forest area of Ethiopia to 2.5 % with respect to the total area. Regarding the discharge formation process, land cover change supports generation of surface flow because of degradation of the surface roughness with two mainly negative effects: more surface runoff and less vegetation cover leads to erosion and degradation of soils. On the other hand, the water available for plants (soil moisture) may be reduced by a decreasing infiltration rate. Both effects have consequences for agricultural production and lead to an increasing demand for irrigation. Thus, the combination of the processes may accelerate the negative environmental response which makes the system highly vulnerable and sensitive to changes in driving forces. This study aims at analyzing the correlation of possible regional drivers with the inter-seasonal and inter-annual variability of subcatchment discharge generation. The study will be carried out applying the eco-hydrological model SWIM (Soil and Water Integrated Model) driven by observed and scenario climate data. Based on satellite image information the effect

  7. Effects of lateral boundary condition resolution and update frequency on regional climate model predictions

    NASA Astrophysics Data System (ADS)

    Pankatz, Klaus; Kerkweg, Astrid

    2015-04-01

    The work presented is part of the joint project "DecReg" ("Regional decadal predictability") which is in turn part of the project "MiKlip" ("Decadal predictions"), an effort funded by the German Federal Ministry of Education and Research to improve decadal predictions on a global and regional scale. In MiKlip, one big question is if regional climate modeling shows "added value", i.e. to evaluate, if regional climate models (RCM) produce better results than the driving models. However, the scope of this study is to look more closely at the setup specific details of regional climate modeling. As regional models only simulate a small domain, they have to inherit information about the state of the atmosphere at their lateral boundaries from external data sets. There are many unresolved questions concerning the setup of lateral boundary conditions (LBC). External data sets come from global models or from global reanalysis data-sets. A temporal resolution of six hours is common for this kind of data. This is mainly due to the fact, that storage space is a limiting factor, especially for climate simulations. However, theoretically, the coupling frequency could be as high as the time step of the driving model. Meanwhile, it is unclear if a more frequent update of the LBCs has a significant effect on the climate in the domain of the RCM. The first study examines how the RCM reacts to a higher update frequency. The study is based on a 30 year time slice experiment for three update frequencies of the LBC, namely six hours, one hour and six minutes. The evaluation of means, standard deviations and statistics of the climate in the regional domain shows only small deviations, some statistically significant though, of 2m temperature, sea level pressure and precipitation. The second part of the first study assesses parameters linked to cyclone activity, which is affected by the LBC update frequency. Differences in track density and strength are found when comparing the simulations

  8. Hydraulic Implications to Upper Basin Stream Systems From Changing Climatic Conditions in the Sierra Nevada

    NASA Astrophysics Data System (ADS)

    Cornwell, K.; Burns, R. G.

    2005-12-01

    Projected climate changes in the Sierra Nevada of northern California may result in more variability in winter storm patterns and an increase in the frequency and magnitude of extreme precipitation events. Changing rain and snow patterns will alter the timing and amount of runoff in the streams that drain the west slope of the Sierra Nevada and will have bearing on water resource management strategies that rely on that runoff. These runoff changes will in turn challenge existing threshold conditions for channel stability, bank erosion, and hill slope stability. Increased sediment loads will impact existing water-routing infrastructure. Hydraulic conditions from several streams that drain the west slope of the Sierra Nevada in the American River drainage basin were measured to assess threshold changes in response to variable discharges. We reconstructed flow conditions from 1997 (early 1997 storms brought widespread flooding to the central and northern Sierra Nevada and peak flows at many gage sites in the region were the largest recorded during historical time) and 2005 in these channels (representing extreme and typical flow conditions) and then looked at changes to cross-sectional areas, flow velocities, channel shear stresses and sediment sizes since 1998 (earliest available sediment data). Initial insights suggest increases to runoff/discharge will likely produce pulses of mobilized coarser materials (resulting from greater channel shear stresses) that may take several years to transport through stream systems, and channel areas that are geologically weak (unconsolidated or weathered surface materials) may be susceptible to substantial erosion. These conditions will likely impact water-routing infrastructure in the upper basins (pipelines, pumps, and turbines) that manage water flow in the Sierra Nevada for much of northern California.

  9. Temperature and dust profiles in Martian dust storm conditions retrieved from Mars Climate Sounder measurements

    NASA Astrophysics Data System (ADS)

    Kleinboehl, A.; Kass, D. M.; Schofield, J. T.; McCleese, D. J.

    2013-12-01

    Mars Climate Sounder (MCS) is a mid- and far-infrared thermal emission radiometer on board the Mars Reconnaissance Orbiter. It measures radiances in limb and nadir/on-planet geometry from which vertical profiles of atmospheric temperature, water vapor, dust and condensates can be retrieved in an altitude range from 0 to 80 km and with a vertical resolution of ~5 km. Due to the limb geometry used as the MCS primary observation mode, retrievals in conditions with high aerosol loading are challenging. We have developed several modifications to the MCS retrieval algorithm that will facilitate profile retrievals in high-dust conditions. Key modifications include a retrieval option that uses a surface pressure climatology if a pressure retrieval is not possible in high dust conditions, an extension of aerosol retrievals to higher altitudes, and a correction to the surface temperature climatology. In conditions of a global dust storm, surface temperatures tend to be lower compared to standard conditions. Taking this into account using an adaptive value based on atmospheric opacity leads to improved fits to the radiances measured by MCS and improves the retrieval success rate. We present first results of these improved retrievals during the global dust storm in 2007. Based on the limb opacities observed during the storm, retrievals are typically possible above ~30 km altitude. Temperatures around 240 K are observed in the middle atmosphere at mid- and high southern latitudes after the onset of the storm. Dust appears to be nearly homogeneously mixed at lower altitudes. Significant dust opacities are detected at least up to 70 km altitude. During much of the storm, in particular at higher altitudes, the retrieved dust profiles closely resemble a Conrath-profile.

  10. Stress and body condition are associated with climate and demography in Asian elephants

    PubMed Central

    Mumby, Hannah S.; Mar, Khyne U.; Thitaram, Chatchote; Courtiol, Alexandre; Towiboon, Patcharapa; Min-Oo, Zaw; Htut-Aung, Ye; Brown, Janine L.; Lummaa, Virpi

    2015-01-01

    Establishing links between ecological variation, physiological markers of stress and demography is crucial for understanding how and why changes in environmental conditions affect population dynamics, and may also play a key role for conservation efforts of endangered species. However, detailed longitudinal studies of long-lived species are rarely available. We test how two markers of stress and body condition vary through the year and are associated with climatic conditions and large-scale mortality and fertility variation in the world's largest semi-captive population of Asian elephants employed in the timber industry in Myanmar. Glucocorticoid metabolites (used as a proxy for stress levels in 75 elephants) and body weight (used as a proxy for condition in 116 elephants) were monitored monthly across a typical monsoon cycle and compared with birth and death patterns of the entire elephant population over half a century (n = 2350). Our results show seasonal variation in both markers of stress and condition. In addition, this variation is correlated with population-level demographic variables. Weight is inversely correlated with population mortality rates 1 month later, and glucocorticoid metabolites are negatively associated with birth rates. Weight shows a highly positive correlation with rainfall 1 month earlier. Determining the factors associated with demography may be key to species conservation by providing information about the correlates of mortality and fertility patterns. The unsustainability of the studied captive population has meant that wild elephants have been captured and tamed for work. By elucidating the correlates of demography in captive elephants, our results offer management solutions that could reduce the pressure on the wild elephant population in Myanmar. PMID:27293715

  11. Accelerated wastage of the Monte Perdido Glacier in the Spanish Pyrenees during recent stationary climatic conditions

    NASA Astrophysics Data System (ADS)

    López-Moreno, J. I.; Revuelto, J.; Rico, I.; Chueca-Cía, J.; Julián, A.; Serreta, A.; Serrano, E.; Vicente-Serrano, S. M.; Azorín-Molina, C.; Alonso-González, E.; García-Ruiz, J. M.

    2015-09-01

    This paper analyzes the evolution of the Monte Perdido Glacier, the third largest glacier of the Pyrenees, from 1981 to the present. We assessed the evolution of the glacier's surface area by use of aerial photographs from 1981, 1999, and 2006, and changes in ice volume by geodetic methods with digital elevation models (DEMs) generated from topographic maps (1981 and 1999), airborne LIDAR (2010) and terrestrial laser scanning (TLS, 2011, 2012, 2013, and 2014). We interpreted the changes in the glacier based on climate data from a nearby meteorological station. The results indicate an accelerated degradation of this glacier after 2000, with a rate of ice surface loss that was almost three-times greater from 2000 to 2006 than for earlier periods, and a doubling of the rate of ice volume loss from 1999 to 2010 (the ice depth decreased 8.98 ± 1.8 m, -0.72 ± 0.14 m w.e. yr-1) compared to 1981 to 1999 (the ice depth decreased 8.35 ± 2.12 m, -0.39 ± 0.1 m w.e. yr-1). This loss of glacial ice has continued from 2011 to 2014 (the ice depth decreased 2.1 ± 0.4 m, -0.64 ± 0.36 m w.e. yr-1). Local climatic changes during the study period cannot explain the acceleration in wastage rate of this glacier, because local precipitation and snow accumulation increased slightly, and local air temperature during the ablation period did not significantly increase. The accelerated degradation of this glacier in recent years can be explained by the lack of equilibrium between the glacier and the current climatic conditions. In particular, the average air temperature increased by at least 0.9 °C in this region since the end of the Little Ice Age (LIA) in the mid-1800s. Thus, this glacier shrinks dramatically during years with low accumulation or high air temperatures during the ablation season, but cannot recover during years with high accumulation or low air temperatures during the ablation season. The most recent TLS data support this interpretation. These data indicated that two

  12. Can environmental conditions affect smallholders' climate change perception? Evidence from an aridity gradient in the Gobi desert.

    NASA Astrophysics Data System (ADS)

    Rueff, Henri

    2016-04-01

    There is a growing interest in smallholders' climate change perception (CCP). Understanding what people perceive in relation to the climate they endure supports national climate change adaptation policy especially relevant to uncertain and resource-scarce environments. Most research so far focused on the accuracy of CCP compared to observed climatic data. However, the potential effect of factors influencing peoples' perceptions remains largely unstudied. This research tests two hypotheses in a desert environment; first, that CCP varies along an aridity gradient, and, second, that respondents are more consistent (answers less far apart) in their CCP when facing more climate shocks, which supports the first hypothesis. A semi-structured survey was conducted among nomadic (Mongolia) (n=180) and semi-nomadic (Inner Mongolia-China) (n=180) herders, to analyse perception along an aridity gradient (proxied by Normalised Difference Vegetation Index) covering an array of climate change issues in the Gobi. Results suggests that environmental conditions have a significant effect on CCP but only in terms of experienced climate shocks. The CCP for other climatic variables (rain, season length) is more diffused and can poorly be predicted by the surrounding environment smallholders live in. Institutional contrasts between China and Mongolia explain marginally differences of perception. Further research is needed to validate these results among smallholders on other environmental gradient types, for examples along altitudinal biome stratification in mountain environments.

  13. Projecting impacts of climate change on hydrological conditions and biotic responses in a chalk valley riparian wetland

    NASA Astrophysics Data System (ADS)

    House, A. R.; Thompson, J. R.; Acreman, M. C.

    2016-03-01

    Projected changes in climate are likely to substantially impact wetland hydrological conditions that will in turn have implications for wetland ecology. Assessing ecohydrological impacts of climate change requires models that can accurately simulate water levels at the fine-scale resolution to which species and communities respond. Hydrological conditions within the Lambourn Observatory at Boxford, Berkshire, UK were simulated using the physically based, distributed model MIKE SHE, calibrated to contemporary surface and groundwater levels. The site is a 10 ha lowland riparian wetland where complex geological conditions and channel management exert strong influences on the hydrological regime. Projected changes in precipitation, potential evapotranspiration, channel discharge and groundwater level were derived from the UK Climate Projections 2009 ensemble of climate models for the 2080s under different scenarios. Hydrological impacts of climate change differ through the wetland over short distances depending on the degree of groundwater/surface-water interaction. Discrete areas of groundwater upwelling are associated with an exaggerated response of water levels to climate change compared to non-upwelling areas. These are coincident with regions where a weathered chalk layer, which otherwise separates two main aquifers, is absent. Simulated water levels were linked to requirements of the MG8 plant community and Desmoulin's whorl snail (Vertigo moulinsiana) for which the site is designated. Impacts on each are shown to differ spatially and in line with hydrological impacts. Differences in water level requirements for this vegetation community and single species highlight the need for separate management strategies in distinct areas of the wetland.

  14. Relating changes of organic matter composition of two German peats to climatic conditions during peat formation

    NASA Astrophysics Data System (ADS)

    Knicker, Heike; Nikolova, Radoslava; Rumpel, Cornelia; González-Vila, Francisco, J.; Drösler, Matthias

    2010-05-01

    Peatlands have been recognized as an important factor within the global C-cycle, since they store about one-third of the global terrestrial C-pool. Furthermore, peat deposits have the potential to record detailed paleoclimatic and - vegetational changes. They are formed in peculiar paleoecosystems where the slow biodegradation of plant residues depends on a series of pedo-climatic and hydromorphic factors leading to a progressive accumulation of organic matter stabilized in different evolutionary stages. Thus, its chemical composition should be applicable as a fingerprint of former prevailing environmental conditions and vegetation configurations. The aim of the present work was to identify this fingerprint in the cores of two German fens, one derived from the Havelland close to Berlin (Großer Bolchow) and the other derived from the alpine region of Bavaria (Kendlmühlfilzen) by investigating the organic matter transformation as a function of peat depths. The C/N ratios and δ13C values revealed several distinctive trends in the two profiles related to prevailing peat forming conditions. Compared to the other layers, at depths of 14-85 cm and 132-324 cm in the Kendlmühlfilzen fen, high C/N ratios and less depleted δ13C values, indicated that the accumulation of these two layers occurred during a humid and cold period. In the case of the "Großer Bolchow", algal contributions were clearly detected using δ13C values. Solid-state 13C NMR spectroscopy demonstrated loss of celluloses and accumulation of lipids and lignin derivatives during peatification, confirming that under the mostly O2-depleted conditions in peats, decomposition was selective. The results obtained by pyrolysis-GC/MS were in good agreement with the NMR data showing that processes ascribed to gradual biotransformation of the lignin occurred in both peats. However, the "Großer Bolchow" peat revealed a more advanced decomposition stage then the "Kendlmühlfilzen" peat, which is in agreement with

  15. Analysis of climate change effects on runoff conditions of two small catchments using climate-runoff models

    NASA Astrophysics Data System (ADS)

    Csóka, Gergely; Béla Brolly, Gábor; Czimber, Kornél; Gálos, Borbála; Kalicz, Péter; Gribovszki, Zoltán

    2014-05-01

    Nowadays global climate change is one of the most discussed scientific topic. According to prognosis (both optimistic and pessimistic) Hungarian economy will have to deal with serious difficulties in consequence of air temperature and precipitation changes. Preparing for climate change inducing problems in this paper climate-runoff (Budyko type) models were employed for two small catchments (Béci- and Kürtös-creek) in South Western Hungary. There were trusty long term runoff and precipitation time series, as well as spatially-distributed precipitation and evapotranspiration maps (validated by locally measured precipitation and runoff data) available. The climate change dataset was calculated on the basis of the prognosis of twelve regional climate models. Spatially-distributed calibration parameter of Budyko-model was calculated by using temperature, precipitation and areal ET maps. The parameter map aggregates all of the factors affecting ET. This map is used for evaluating future ET and runoff in spatially-distributed mode. In spite of the fact results have some inaccuracy, in the order of magnitude they reliably show that annual runoff of analysed catchments will have strong recession (46% for Béci and 51% for Kürtös creek) to the end of the 21st century. This publication has been supported by TÁMOP-4.2.2.A-11/1/KONV-2012-0013 project. The research of Zoltán Gribovszki was supported by the European Union and the State of Hungary, co-financed by the European Social Fund in the framework of TÁMOP 4.2.4. A/2-11-1-2012-0001 'National Excellence Program'.

  16. Farmer Health and Adaptive Capacity in the Face of Climate Change and Variability. Part 1: Health as a Contributor to Adaptive Capacity and as an Outcome from Pressures Coping with Climate Related Adversities

    PubMed Central

    Berry, Helen L.; Hogan, Anthony; Ng, Suan Peng; Parkinson, Anne

    2011-01-01

    This paper examines the role farmers’ health plays as an element of adaptive capacity. The study examines which of twenty aspects of adaptation may be related to overall health outcomes, controlling for demographic and on-farm-factors in health problems. The analysis is based on 3,993 farmers’ responses to a national survey of climate risk and adaptation. Hierarchical linear regression modelling was used examine the extent to which, in a multivariate analysis, the use of adaptive practices was predictively associated with self-assessed health, taking into account the farmer’s rating of whether their health was a barrier to undertaking farm work. We present two models, one excluding pre-existing health (model 1) and one including pre-existing health (model 2). The first model accounted for 21% of the variance. In this model better health was most strongly predicted by an absence of on-farm risk, greater financial viability, greater debt pressures, younger age and a desire to continue farming. Social capital (trust and reciprocity) was moderately associated with health as was the intention to adopt more sustainable practices. The second model (including the farmers’ health as a barrier to undertaking farm work) accounted for 43% of the variance. Better health outcomes were most strongly explained, in order of magnitude, by the absence of pre-existing health problems, greater access to social support, greater financial viability, greater debt pressures, a desire to continue farming and the condition of on-farm resources. Model 2 was a more parsimonious model (only nine predictors, compared with 15 in model 1), and explained twice as much variance in health outcomes. These results suggest that (i) pre-existing health problems are a very important factor to consider when designing adaptation programs and policies and (ii) these problems may mediate or modify the relationship between adaptation and health. PMID:22073027

  17. Performance degradation of grid-tied photovoltaic modules in a hot-dry climatic condition

    NASA Astrophysics Data System (ADS)

    Suleske, Adam; Singh, Jaspreet; Kuitche, Joseph; Tamizh-Mani, Govindasamy

    2011-09-01

    The crystalline silicon photovoltaic (PV) modules under open circuit conditions typically degrade at a rate of about 0.5% per year. However, it is suspected that the modules in an array level may degrade, depending on equipment/frame grounding and array grounding, at higher rates because of higher string voltage and increased module mismatch over the years of operation in the field. This paper compares and analyzes the degradation rates of grid-tied photovoltaic modules operating over 10-17 years in a desert climatic condition of Arizona. The nameplate open-circuit voltages of the arrays ranged between 400 and 450 V. Six different types/models of crystalline silicon modules with glass/glass and glass/polymer constructions were evaluated. About 1865 modules were inspected using an extended visual inspection checklist and infrared (IR) scanning. The visual inspection checklist included encapsulant discoloration, cell/interconnect cracks, delamination and corrosion. Based on the visual inspection and IR studies, a large fraction of these modules were identified as allegedly healthy and unhealthy modules and they were electrically isolated from the system for currentvoltage (I-V) measurements of individual modules. The annual degradation rate for each module type is determined based on the I-V measurements.

  18. Effects of Climate and Sewer Condition on Virus Transport to Groundwater.

    PubMed

    Gotkowitz, Madeline B; Bradbury, Kenneth R; Borchardt, Mark A; Zhu, Jun; Spencer, Susan K

    2016-08-16

    Pathogen contamination from leaky sanitary sewers poses a threat to groundwater quality in urban areas, yet the spatial and temporal dimensions of this contamination are not well understood. In this study, 16 monitoring wells and six municipal wells were repeatedly sampled for human enteric viruses. Viruses were detected infrequently, in 17 of 455 samples, compared to previous sampling at these wells. Thirteen of the 22 wells sampled were virus-positive at least once. While the highest virus concentrations occurred in shallower wells, shallow and deep wells were virus-positive at similar rates. Virus presence in groundwater was temporally coincident, with 16 of 17 virus-positive samples collected in a six-month period. Detections were associated with precipitation and occurred infrequently during a prolonged drought. The study purposely included sites with sewers of differing age and material. The rates of virus detections in groundwater were similar at all study sites during this study. However, a relationship between sewer age and virus detections emerged when compared to data from an earlier study, conducted during high precipitation conditions. Taken together, these data indicate that sewer condition and climate affect urban groundwater contamination by human enteric viruses. PMID:27434550

  19. Accumulation of pharmaceuticals in groundwater under arid climate conditions - Results from unsaturated column experiments.

    PubMed

    Zemann, M; Majewsky, M; Wolf, L

    2016-07-01

    Intense reuse of treated wastewater in agriculture is practiced all over the world, especially in arid and water-scarce regions. In doing so, pharmaceutical residues in the water are irrigated to the soil and subsequently can percolate into the local aquifers. Since evaporation rates in these areas are typically high, persistent substances might enrich in the groundwater recharge of closed catchments like the Jordan Valley. Against this background, unsaturated column tests were conducted to investigate the potential for evaporative accumulation of the two pharmaceuticals bezafibrate and carbamazepine under simulated arid climate conditions. Parallel tests were conducted with inhibited microbiological activity where both substances showed an increase in the effluent concentrations proportional to the evaporation loss of the inflow solution. The mean accumulation factors of the pharmaceuticals correspond to the evaporated water loss. The experiments indicate the accumulation potential for pharmaceuticals with high persistence against biodegradation. For the first time, the overall potential for evaporative enrichment could be demonstrated for pharmaceuticals. Under the given experimental conditions, the two investigated pharmaceuticals did not enrich faster than chloride, which might result in soil salting prior to reaching harmful pharmaceutical concentrations in soil water. The findings are relevant to future assessments of environmental impacts of persistent trace substances, which need to take into account that concentrations in the aquatic cycle might increase further due to evaporative enrichment. PMID:27085060

  20. Impact of Climate Conditions on Occupational Health and Related Economic Losses: A New Feature of Global and Urban Health in the Context of Climate Change.

    PubMed

    Kjellstrom, Tord

    2016-03-01

    One feature of climate change is the increasing heat exposure in many workplaces where efficient cooling systems cannot be applied. Excessive heat exposure is a particular problem for working people because of the internal heat production when muscle work is carried out. The physiological basis for severe heat stroke, other clinical effects, and heat exhaustion is well known. One feature of this health effect of excessive workplace heat exposure is reduced work capacity, and new research has started to quantify this effect in the context of climate change. Current climate conditions in tropical and subtropical parts of the world are already so hot during the hot seasons that occupational health effects occur and work capacity for many working people is affected. The Hothaps-Soft database and software andClimateCHIP.orgwebsite make it possible to rapidly produce estimates of local heat conditions and trends. The results can be mapped to depict the spatial distribution of workplace heat stress. In South-East Asia as much as 15% to 20% of annual work hours may already be lost in heat-exposed jobs, and this may double by 2050 as global climate change progresses. By combining heat exposure data and estimates of the economic consequences, the vulnerability of many low- and middle-income countries is evident. The annual cost of reduced labor productivity at country level already in 2030 can be several percent of GDP, which means billions of US dollars even for medium-size countries. The results provide new arguments for effective climate change adaptation and mitigation policies and preventive actions in all countries. PMID:25626424

  1. Groundwater Management Policies for Maintaining Stream Flow Given Variable Climatic Conditions

    NASA Astrophysics Data System (ADS)

    Pohll, G.; Carroll, R. W.; Brozovic, N.

    2012-12-01

    Groundwater is an important resource to agriculture throughout the semi-arid United States, where farmers often supplement surface water diversions with groundwater pumping. Understanding the complex exchange over space and time between rivers and aquifers is important in developing management alternatives that are capable of preserving stream flow for habitat and increasing water deliveries downstream while minimizing lost crop production. Previous integrated hydrologic-economic models have generally assumed superposition of the impacts of groundwater pumping on the hydrologic system for analytical tractability. Although this assumption may be reasonable for some surface water-groundwater systems, in many systems the behavior diverges considerably from the linear assumption. We present analyses using an integrated hydrologic-economic model of surface water-groundwater interaction with nonlinear dynamics, developed for the Mason Valley area in Nevada. The study area has active water conflict between upstream and downstream water users, where groundwater pumping has an important impact on streamflow. The model replicates the movement of water throughout the coupled river and aquifer of the Walker River system and is used to analyze hypothetical tradeoffs between increasing streamflow at the basin outlet and meeting crop water demands for irrigation. The model is run from 1997 to 2006 to capture wet and dry climatic conditions, including a four year drought period in which groundwater pumping accounts for more than 50% of the irrigated water budget. Three alternate groundwater management policies are analyzed to compare economic performance (resulting from reductions in crop area due to reduced groundwater pumping) and hydrologic impact (in terms of increased stream discharge at the basin outlet). First, uniform pumping quotas are the simplest policy to implement and are modeled here as equal reductions in groundwater pumping for each stakeholder at a lumped field

  2. Modelling hydrological extremes under non-stationary conditions using climate covariates

    NASA Astrophysics Data System (ADS)

    Vasiliades, Lampros; Galiatsatou, Panagiota; Loukas, Athanasios

    2013-04-01

    Extreme value theory is a probabilistic theory that can interpret the future probabilities of occurrence of extreme events (e.g. extreme precipitation and streamflow) using past observed records. Traditionally, extreme value theory requires the assumption of temporal stationarity. This assumption implies that the historical patterns of recurrence of extreme events are static over time. However, the hydroclimatic system is nonstationary on time scales that are relevant to extreme value analysis, due to human-mediated and natural environmental change. In this study the generalized extreme value (GEV) distribution is used to assess nonstationarity in annual maximum daily rainfall and streamflow timeseries at selected meteorological and hydrometric stations in Greece and Cyprus. The GEV distribution parameters (location, scale, and shape) are specified as functions of time-varying covariates and estimated using the conditional density network (CDN) as proposed by Cannon (2010). The CDN is a probabilistic extension of the multilayer perceptron neural network. Model parameters are estimated via the generalized maximum likelihood (GML) approach using the quasi-Newton BFGS optimization algorithm, and the appropriate GEV-CDN model architecture for the selected meteorological and hydrometric stations is selected by fitting increasingly complicated models and choosing the one that minimizes the Akaike information criterion with small sample size correction. For all case studies in Greece and Cyprus different formulations are tested with combinational cases of stationary and nonstationary parameters of the GEV distribution, linear and non-linear architecture of the CDN and combinations of the input climatic covariates. Climatic indices such as the Southern Oscillation Index (SOI), which describes atmospheric circulation in the eastern tropical pacific related to El Niño Southern Oscillation (ENSO), the Pacific Decadal Oscillation (PDO) index that varies on an interdecadal

  3. Global atmospheric sulfur budget under volcanically quiescent conditions: Aerosol-chemistry-climate model predictions and validation

    NASA Astrophysics Data System (ADS)

    Sheng, Jian-Xiong; Weisenstein, Debra K.; Luo, Bei-Ping; Rozanov, Eugene; Stenke, Andrea; Anet, Julien; Bingemer, Heinz; Peter, Thomas

    2015-01-01

    The global atmospheric sulfur budget and its emission dependence have been investigated using the coupled aerosol-chemistry-climate model SOCOL-AER. The aerosol module comprises gaseous and aqueous sulfur chemistry and comprehensive microphysics. The particle distribution is resolved by 40 size bins spanning radii from 0.39 nm to 3.2 μm, including size-dependent particle composition. Aerosol radiative properties required by the climate model are calculated online from the aerosol module. The model successfully reproduces main features of stratospheric aerosols under nonvolcanic conditions, including aerosol extinctions compared to Stratospheric Aerosol and Gas Experiment II (SAGE II) and Halogen Occultation Experiment, and size distributions compared to in situ measurements. The calculated stratospheric aerosol burden is 109 Gg of sulfur, matching the SAGE II-based estimate (112 Gg). In terms of fluxes through the tropopause, the stratospheric aerosol layer is due to about 43% primary tropospheric aerosol, 28% SO2, 23% carbonyl sulfide (OCS), 4% H2S, and 2% dimethyl sulfide (DMS). Turning off emissions of the short-lived species SO2, H2S, and DMS shows that OCS alone still establishes about 56% of the original stratospheric aerosol burden. Further sensitivity simulations reveal that anticipated increases in anthropogenic SO2 emissions in China and India have a larger influence on stratospheric aerosols than the same increase in Western Europe or the U.S., due to deep convection in the western Pacific region. However, even a doubling of Chinese and Indian emissions is predicted to increase the stratospheric background aerosol burden only by 9%. In contrast, small to moderate volcanic eruptions, such as that of Nabro in 2011, may easily double the stratospheric aerosol loading.

  4. Uncertainty of the hydrological response to climate change conditions; 605 basins, 3 hydrological models, 5 climate models, 5 hydrological variables

    NASA Astrophysics Data System (ADS)

    Melsen, Lieke; Mizukami, Naoki; Newman, Andrew; Clark, Martyn; Teuling, Adriaan

    2016-04-01

    Many studies investigated the effect of a changing climate on the hydrological response of a catchment and uncertainty of the effect coming from hydrologic modelling (e.g., forcing, hydrologic model structures, and parameters). However, most past studies used only a single or a small number of catchments. To go beyond the case-study, and to assess the uncertainty involved in modelling the hydrological impact of climate change more comprehensively, we studied 605 basins over a wide range of climate regimes throughout the contiguous USA. We used three different widely-used hydrological models (VIC, HBV, SAC), which we forced with five distinct climate model outputs. The hydrological models have been run for a base period (1986-2008) for which observations were available, and for a future period (2070-2099). Instead of calibrating each hydrological model for each basin, the model has been run with a parameter sample (varying from 1600 to 1900 samples dependent on the number of free parameters in the model). Five hydrological states and fluxes were stored; discharge, evapotranspiration, soil moisture, SWE and snow melt, and 15 different metrics and signatures have been obtained for each model run. With the results, we conduct a sensitivity analysis over the change in signatures from the future period compared to the base period. In this way, we can identify the parameters that are responsible for certain projected changes, and identify the processes responsible for this change. By using three different models, in which VIC is most distinctive in including explicit vegetation parameters, we can compare different process representations and the effect on the projected hydrological change.

  5. Impact of urban WWTP and CSO fluxes on river peak flow extremes under current and future climate conditions.

    PubMed

    Keupers, Ingrid; Willems, Patrick

    2013-01-01

    The impact of urban water fluxes on the river system outflow of the Grote Nete catchment (Belgium) was studied. First the impact of the Waste Water Treatment Plant (WWTP) and the Combined Sewer Overflow (CSO) outflows on the river system for the current climatic conditions was determined by simulating the urban fluxes as point sources in a detailed, hydrodynamic river model. Comparison was made of the simulation results on peak flow extremes with and without the urban point sources. In a second step, the impact of climate change scenarios on the urban fluxes and the consequent impacts on the river flow extremes were studied. It is shown that the change in the 10-year return period hourly peak flow discharge due to climate change (-14% to +45%) was in the same order of magnitude as the change due to the urban fluxes (+5%) in current climate conditions. Different climate change scenarios do not change the impact of the urban fluxes much except for the climate scenario that involves a strong increase in rainfall extremes in summer. This scenario leads to a strong increase of the impact of the urban fluxes on the river system. PMID:23787302

  6. Response of tree growth to climatic variation and stand dynamics: Implications for modeling stand dynamics under varying climatic conditions

    SciTech Connect

    Graumlich, L.J.; Holmes, R.L. )

    1994-06-01

    We used tree-ring data to assess the relative importance of regional climate vs. stand-level processes in controlling tree growth for seven forest dominants of the mixed conifer forest of the Sierra Nevada. For each species, increment cores were collected from at least 20 canopy dominants at several sites arrayed along elevational gradients extending from lower to upper elevational limits. Species sampled include ponderosa pine (Pinus ponderosa), Jeffrey pine (P. jeffreyi), sugar pine (P. lambertina), white fir (Abies concolor), red fir (A. magnifica), incense cedar (Calocedrus decurrens), and black oak (Quercus keloggii). Stand-level processes generate low to medium frequency variation in growth that is not held in common among trees within a site or between sites. Stand-level processes are most important for white and red fir and least important for ponderosa pine. Regional climatic variation generates medium to high frequency variation that is coherent among trees of the same species (and often same genera). Results such as these have utility for parameterizing and validating stand simulation models, especially for use in climatic change scenarios.

  7. Exceptional ocean surface conditions on the SE Greenland shelf during the Medieval Climate Anomaly

    NASA Astrophysics Data System (ADS)

    Miettinen, Arto; Divine, Dmitry V.; Husum, Katrine; Koç, Nalan; Jennings, Anne

    2015-12-01

    Diatom inferred 2900 year long records of August sea surface temperature (aSST) and April sea ice concentration (aSIC) are generated from a marine sediment core from the SE Greenland shelf with a special focus on the interval ca. 870-1910 Common Era (C.E.) reconstructed in subdecadal temporal resolution. The Medieval Climate Anomaly (MCA) between 1000 and 1200 C.E. represents the warmest ocean surface conditions of the SE Greenland shelf over the late Holocene (880 B.C.E.(before the Common Era) to 1910 C.E.). It was characterized by abrupt, decadal to multidecadal changes, such as an abrupt warming of ~2.4°C in 55 years around 1000 C.E. Temperature changes of these magnitudes are rare on the North Atlantic proxy data. Compared to regional air temperature reconstructions, our results indicate a lag of about 50 years in ocean surface warming either due to increased freshwater discharge from the Greenland ice sheet or intensified sea ice export from the Arctic as a response to atmospheric warming at the beginning of the MCA. A cool phase, from 1200-1890 C.E., associated with the Little Ice Age, ends with the rapid warming of aSST and diminished aSIC in the early twentieth century. The results show that the periods of warm aSST and aSIC minima are coupled with solar minima suggesting that solar forcing possibly amplified by atmospheric forcing have been behind the variability of surface conditions on the SE Greenland over the last millennium. The results indicate that the SE Greenland shelf is a climatologically sensitive area where extremely rapid changes are possible and highlights the importance of the area under the present warming conditions.

  8. Eco-Hydro-Geomorphic Response of Semiarid Hillslopes to Changing Anthropic and Climatic Conditions

    NASA Astrophysics Data System (ADS)

    Moreno De Las Heras, M.; Saco, P. M.

    2012-12-01

    The vegetation of semiarid areas regions is frequently sparse, with mixed herbaceous and woody plant species displaying both negative (competition) and positive (facilitation) interactions. Shifts in the vegetation structure which result from climatic or anthropic effects, alter the hydrologic response of these systems and can have very diverse impacts on ecosystem functioning. For example, in the southeastern US changes from grassland to shrublands have been linked to degradation processes. However the opposite has been observed in areas of Australia and Spain, in which shrubs have been found to improve the conditions for understory grasses promoting restoration. Here we use a spatial ecogeormorphologic model that simulates the dynamics of runoff redistribution and erosion for hillslopes with patterned vegetation. The patterned vegetation module accounts for coexisting plant species and their varying effects on key hydrologic processes like infiltration and evaporation. Plants species that act as ecosystems engineers preferentially enhance infiltration rates and reduce evaporation due to shading, and therefore have a key impact on water redistribution at the hillslope scale. The development of a spatially variable infiltration field with low infiltration rates in the bare soil areas (due to surface crusting) and high infiltration rates in the vegetated areas (due to improved soil aggregation and macroporosity) is responsible for the emergence of a runoff-runon system, which determines the surface hydrologic connectivity of the landscape and sediment redistribution. We find that the introduction of different shrub species with varying degree of preferential infiltration enhancement and shading effects, can explain the contrasting observations described above. Implications for restoration efforts are illustrated using observations from agricultural sites in central Australia and reclaimed mining sites in Spain. We simulated and analysed the ecogeomorphic evolution

  9. Integrated analysis of present and future responses of precipitation over selected Greek areas with different climate conditions

    NASA Astrophysics Data System (ADS)

    Paparrizos, Spyridon; Maris, Fotios; Matzarakis, Andreas

    2016-03-01

    The assessment of future precipitation variations prevailing in an area is essential for the research regarding climate and climate change. The current paper focuses on 3 selected areas in Greece that present different climatic characteristics due to their location and aims to assess and compare the future variation of annual and seasonal precipitation. Future precipitation data from the ENSEMBLES anthropogenic climate-change (ACC) global simulations and the Climate version of the Local Model (CLM) were obtained and analyzed. The climate simulations were performed for the future periods 2021-2050 and 2071-2100 under the A1B and B1 scenarios. Mann-Kendall test was applied to investigate possible trends. Spatial distribution of precipitation was performed using a combination of dynamic and statistical downscaling techniques and Kriging method within ArcGIS 10.2.1. The results indicated that for both scenarios, reference periods and study areas, precipitation is expected to be critically decreased. Additionally, Mann-Kendall test application showed a strong downward trend for every study area. Furthermore, the decrease in precipitation for the Ardas River basin characterized by the continental climate will be tempered, while in the Sperchios River basin it will be smoother due to the influence of some minor climatic variations in the basins' springs in the highlands where milder conditions occur. Precipitation decrease in the Geropotamos River basin which is characterized by Mediterranean climate will be more vigorous. B1 scenario appeared more optimistic for the Ardas and Sperchios River basins, while in the Geropotamos River basin, both applied scenarios brought similar results, in terms of future precipitation response.

  10. Directed International Technological Change and Climate Policy: New Methods for Identifying Robust Policies Under Conditions of Deep Uncertainty

    NASA Astrophysics Data System (ADS)

    Molina-Perez, Edmundo

    : climate change, elasticity of substitution between renewable and fossil energy and three different sources of technological uncertainty (i.e. R&D returns, innovation propensity and technological transferability). The performance of eight different GCF and non-GCF based policy regimes is evaluated in light of various end-of-century climate policy targets. Then I combine traditional scenario discovery data mining methods (Bryant and Lempert, 2010) with high dimensional stacking methods (Suzuki, Stem and Manzocchi, 2015; Taylor et al., 2006; LeBlanc, Ward and Wittels, 1990) to quantitatively characterize the conditions under which it is possible to stabilize greenhouse gas emissions and keep temperature rise below 2°C before the end of the century. Finally, I describe a method by which it is possible to combine the results of scenario discovery with high-dimensional stacking to construct a dynamic architecture of low cost technological cooperation. This dynamic architecture consists of adaptive pathways (Kwakkel, Haasnoot and Walker, 2014; Haasnoot et al., 2013) which begin with carbon taxation across both regions as a critical near term action. Then in subsequent phases different forms of cooperation are triggered depending on the unfolding climate and technological conditions. I show that there is no single policy regime that dominates over the entire uncertainty space. Instead I find that it is possible to combine these different architectures into a dynamic framework for technological cooperation across regions that can be adapted to unfolding climate and technological conditions which can lead to a greater rate of success and to lower costs in meeting the end-of-century climate change objectives agreed at the 2015 Paris Conference of the Parties. Keywords: international technological change, emerging nations, climate change, technological uncertainties, Green Climate Fund.

  11. Agricultural machineries wheeling and soil qualities mapping in climatic changes conditions

    NASA Astrophysics Data System (ADS)

    Bergonzoli, S.; Servadio, P.

    2012-04-01

    and on control areas, a software GIS was used. Results shown the highest level of soil compaction caused by the traffic of WTN in term of CI and SS. In fact, increment ratio respect to the control measured after the tractors pass were: CI = 0.65 and 0.14 for WTN and for WTEL respectively; SS = 0.65 and 0.46 for WTN and WTEL respectively. Comparing the two different tires, significant differences were found particularly in the surface layers (0-0.20 m depth): mean values of CI and SS were higher for WTN (0.47 and 1.60 respectively) respect to WTEL. Track area covered by the two treatments respect to the whole field (16.32 ha) were: 0.025 for treatment WTN (0.27 m tires width) having an operative work width of 24 m ; 0.075 for treatment WTEL (0.85 m tires width) having an operative work width of 14 m. Results of this study highlighted that, in these field conditions (clay soil, water content over field capacity), tractor pass with very narrow tires caused a soil compaction level too high up to be impossible to traffic into the field. To operate at these soil water content conditions a tractors fitted with low aspect ratio and low inflation pressure tires is necessary. With lower soil water content, narrow tires allow carrying out fertilization into the inter-row avoiding crop trampling and compacting less percentage of field area respect to the a tractor equipped with large tires. Key words: Tractor, Soil trafficability, Soil compaction, Tires, GPS, GIS. Acknowledgements This work was carried out under the auspices of the special project "Sceneries of adaptation of the Italian agriculture to the climatic changes" (AGROSCENARI) of the Agricultural Research Council, and Italian Ministry of the Agricultural and Forestry Politics.

  12. A new coupled ice sheet-climate model: description and sensitivity to model physics under Eemian, Last Glacial Maximum, late Holocene and modern climate conditions

    NASA Astrophysics Data System (ADS)

    Fyke, J. G.; Weaver, A. J.; Pollard, D.; Eby, M.; Carter, L.; Mackintosh, A.

    2010-08-01

    The need to better understand long-term climate/ice sheet feedback loops is motivating efforts to couple ice sheet models into Earth System models which are capable of long-timescale simulations. In this paper we describe a coupled model, that consists of the University of Victoria Earth System Climate Model (UVic ESCM) and the Pennsylvania State University Ice model (PSUI). The climate model generates a surface mass balance (SMB) field via a sub-gridded surface energy/moisture balance model that resolves narrow ice sheet ablation zones. The ice model returns revised elevation, surface albedo and ice area fields, plus coastal fluxes of heat and moisture. An arbitrary number of ice sheets can be simulated, each on their own high-resolution grid and each capable of synchronous or asynchronous coupling with the overlying climate model. The model is designed to conserve global heat and moisture. In the process of improving model performance we developed a procedure to account for modelled surface air temperature (SAT) biases within the energy/moisture balance surface model and improved the UVic ESCM snow surface scheme through addition of variable albedos and refreezing over the ice sheet. A number of simulations for late Holocene, Last Glacial Maximum (LGM), and Eemian climate boundary conditions were carried out to explore the sensitivity of the coupled model and identify model configurations that best represented these climate states. The modelled SAT bias was found to play a significant role in long-term ice sheet evolution, as was the effect of refreezing meltwater and surface albedo. The bias-corrected model was able to reasonably capture important aspects of the Antarctic and Greenland ice sheets, including modern SMB and ice distribution. The simulated northern Greenland ice sheet was found to be prone to ice margin retreat at radiative forcings corresponding closely to those of the Eemian or the present-day.

  13. A new coupled ice sheet/climate model: description and sensitivity to model physics under Eemian, Last Glacial Maximum, late Holocene and modern climate conditions

    NASA Astrophysics Data System (ADS)

    Fyke, J. G.; Weaver, A. J.; Pollard, D.; Eby, M.; Carter, L.; Mackintosh, A.

    2011-03-01

    The need to better understand long-term climate/ice sheet feedback loops is motivating efforts to couple ice sheet models into Earth System models which are capable of long-timescale simulations. In this paper we describe a coupled model that consists of the University of Victoria Earth System Climate Model (UVic ESCM) and the Pennsylvania State University Ice model (PSUI). The climate model generates a surface mass balance (SMB) field via a sub-gridded surface energy/moisture balance model that resolves narrow ice sheet ablation zones. The ice model returns revised elevation, surface albedo and ice area fields, plus coastal fluxes of heat and moisture. An arbitrary number of ice sheets can be simulated, each on their own high-resolution grid and each capable of synchronous or asynchronous coupling with the overlying climate model. The model is designed to conserve global heat and moisture. In the process of improving model performance we developed a procedure to account for modelled surface air temperature (SAT) biases within the energy/moisture balance surface model and improved the UVic ESCM snow surface scheme through addition of variable albedos and refreezing over the ice sheet. A number of simulations for late Holocene, Last Glacial Maximum (LGM), and Eemian climate boundary conditions were carried out to explore the sensitivity of the coupled model and identify model configurations that best represented these climate states. The modelled SAT bias was found to play a significant role in long-term ice sheet evolution, as was the effect of refreezing meltwater and surface albedo. The bias-corrected model was able to reasonably capture important aspects of the Antarctic and Greenland ice sheets, including modern SMB and ice distribution. The simulated northern Greenland ice sheet was found to be prone to ice margin retreat at radiative forcings corresponding closely to those of the Eemian or the present-day.

  14. Wheat breadmaking properties in dependance on wheat enzymes status and climate conditions.

    PubMed

    Tomić, Jelena; Torbica, Aleksandra; Popović, Ljiljana; Hristov, Nikola; Nikolovski, Branislava

    2016-05-15

    The objective of this study was to evaluate albumins profile, proteolytic and amylolytic activity level and baking performance of wheat varieties grown in two production years with different climate conditions (2011 and 2012) in four locations. The results of ANOVA showed that variety, location, production year, and their interactions all had significant effects on all tested wheat quality parameters. The enzymatic activity and specific bread volume were mainly influenced by the variety. The samples from 2012 production year, had the lower values of albumin content, proteolytic and amylolytic activity, and bread specific volume. The correlation analysis, performed for 2011 production year, showed that albumin fraction (15-30 kDa) and proteolytic activity were negatively correlated with bread specific volume indicating the role of this fraction on lowering the crucial bread quality parameter. In 2012 production year, albumin fractions (5-15 kDa; 50-65 kDa) showed the most correlations, especially with parameters of bread quality. PMID:26776009

  15. Thermographic evaluation of climatic conditions on lambs from different genetic groups

    NASA Astrophysics Data System (ADS)

    do Prado Paim, Tiago; Borges, Bárbara Oliveira; de Mello Tavares Lima, Paulo; Gomes, Edgard Franco; Dallago, Bruno Stéfano Lima; Fadel, Rossala; de Menezes, Adriana Morato; Louvandini, Helder; Canozzi, Maria Eugênia Andrighetto; Barcellos, Júlio Otavio Jardim; McManus, Concepta

    2013-01-01

    In production systems the characterization of genetic resources in relation to their capacity to respond to environmental conditions is necessary. The objective of this study was to evaluate the use of infrared thermography for separation of animals from different genetic groups and determine which phenotypic traits are important for climatic adaptation. A total of 126 suckling lambs from four different genetic groups (Santa Inês - SI, Bergamasca - B, Bergamasca X Santa Inês - BS, and Ile de France X Santa Inês - IL) were used. The animals were divided into two groups, one housed and another in an outside paddock. Thermograph photographs were taken at four-hour intervals over three full days. Temperatures of the nose, skull, neck, fore and rear flanks and rump were measured, as well as coat depth, the density and length of hairs, reflectance and color. The daily temperature range during the experimental period was more than 20°C, with animals experiencing heat (12 h to 15 h) and cold (24 h to 4 h) stress. The three main phenotypic traits that influenced genetic group separation were hair density, height of coat, and length of hairs. Thermograph temperatures were able to detect different responses of the genetic groups to the environment. Therefore, infrared thermography is a promising technique to evaluate the response of animals to the environment and to differentiate between genetic groups.

  16. Indoor pollution by organic emissions from textile floor coverings: Climate test chamber studies under static conditions

    NASA Astrophysics Data System (ADS)

    Sollinger, S.; Levsen, K.; Wünsch, G.

    The emission of organic compounds from textile floor coverings was studied in a climate test chamber under static conditions (zero air exchange) in order to test the parameters which influence such chamber experiments, i.e. the temperature, the humidity and the adsorption on the walls. While depending on the volatility and the polarity of the compound, the equilibrium concentrations increase in part substantially with increasing temperature, the humidity has little impact on the observed concentrations. The chamber walls represent an important sink for polar and less volatile compounds, although this sink does not influence the equilibrium concentrations. Ten textile floor coverings have been tested (7 of which had a polyamide pile and a styrene-butadiene rubber backing). Ninety-nine compounds have been identified. The equilibrium concentrations of 20 compounds have been determined. These equilibrium concentrations do not depend on the sample size, the sample loading nor on wall effects, in contrast to the dynamic method, where these parameters play an important role.

  17. Energy-Efficient Supermarket Heating, Ventilation, and Air Conditioning in Humid Climates in the United States

    SciTech Connect

    Clark, J.

    2015-03-01

    Supermarkets are energy-intensive buildings that consume the greatest amount of electricity per square foot of building of any building type in the United States and represent 5% of total U.S. commercial building primary energy use (EIA 2005). Refrigeration and heating, ventilation, and air-conditioning (HVAC) systems are responsible for a large proportion of supermarkets’ total energy use. These two systems sometimes work together and sometimes compete, but the performance of one system always affects the performance of the other. To better understand these challenges and opportunities, the Commercial Buildings team at the National Renewable Energy Laboratory investigated several of the most promising strategies for providing energy-efficient HVAC for supermarkets and quantified the resulting energy use and costs using detailed simulations. This research effort was conducted on behalf of the U.S. Department of Energy (DOE) Commercial Building Partnerships (CBP) (Baechler et al. 2012; Parrish et al. 2013; Antonopoulos et al. 2014; Hirsch et al. 2014). The goal of CBP was to reduce energy use in the commercial building sector by creating, testing, and validating design concepts on the pathway to net zero energy commercial buildings. Several CBP partners owned or operated buildings containing supermarkets and were interested in optimizing the energy efficiency of supermarket HVAC systems in hot-humid climates. These partners included Walmart, Target, Whole Foods Market, SUPERVALU, and the Defense Commissary Agency.

  18. Microbial biogeography of wine grapes is conditioned by cultivar, vintage, and climate

    PubMed Central

    Bokulich, Nicholas A.; Thorngate, John H.; Richardson, Paul M.; Mills, David A.

    2014-01-01

    Wine grapes present a unique biogeography model, wherein microbial biodiversity patterns across viticultural zones not only answer questions of dispersal and community maintenance, they are also an inherent component of the quality, consumer acceptance, and economic appreciation of a culturally important food product. On their journey from the vineyard to the wine bottle, grapes are transformed to wine through microbial activity, with indisputable consequences for wine quality parameters. Wine grapes harbor a wide range of microbes originating from the surrounding environment, many of which are recognized for their role in grapevine health and wine quality. However, determinants of regional wine characteristics have not been identified, but are frequently assumed to stem from viticultural or geological factors alone. This study used a high-throughput, short-amplicon sequencing approach to demonstrate that regional, site-specific, and grape-variety factors shape the fungal and bacterial consortia inhabiting wine-grape surfaces. Furthermore, these microbial assemblages are correlated to specific climatic features, suggesting a link between vineyard environmental conditions and microbial inhabitation patterns. Taken together, these factors shape the unique microbial inputs to regional wine fermentations, posing the existence of nonrandom “microbial terroir” as a determining factor in regional variation among wine grapes. PMID:24277822

  19. Influence of climatic conditions on white tip disease (Phytophthora porri) in leek (Allium porrum).

    PubMed

    De Jonghe, K; Keirsebilck, D; Martens, K; Buysens, S; Höfte, M

    2002-01-01

    In leek, one of the major vegetable crops in Belgium, Phytophthora porri causes the so-called white tip disease. During the growing seasons of 1999, 2000 and 2001 the incidence of the white tip disease and the role of environmental conditions in the appearance were investigated on several non-treated leek fields in Flanders (Belgium). The first symptoms of white tip disease on leek where recorded in July and the disease progressed until March. Lesions appeared after an incubation period of 91 to 204 DD (degree days above -3 degrees C) (t0) and were diagnostic at 120 DD. The obtained data confirmed a disease increase corresponding with an amount of rainfall of more than 20 l/m2 in 4 days in the period t = t0-92 to t = t0-154 DD. A good correlation was found between the daily disease increase on one hand and the leaf wetness, relative humidity and temperature (negative correlation) on the other hand. Daily disease increase only weakly correlated with rainfall. Based on these results recommendations can be made (for further studies) to develop a model, combining several of the climatic factors, to predict infection periods with high risk on disease increase in the production of leek. PMID:12701432

  20. Relationship of climatic conditions to fecal corticosterone levels of captive cheetahs reared in Japan.

    PubMed

    Uetake, Katsuji; Une, Yumi; Ito, Shu; Yamabe, Marino; Toyoda, Hideto; Tanaka, Toshio

    2014-10-01

    To assess the stress level of cheetahs reared in Japan and to identify the prime components of the climatic conditions that affect their thermal stress, fecal corticosterone was monitored for 8 months from May to the following January. A total of 203 fecal samples were gathered in the morning from seven adult cheetahs that were kept at a zoological garden in Wakayama, Japan. Cheetahs were on exhibit singly or together with a harmonious conspecific during the day, but housed singly at night. Although the monthly fluctuation in corticosterone concentrations was not significant, the concentrations were relatively low during the summer season. Individual differences among cheetahs and the interaction effect between individual and month on the corticosterone concentrations were significant. Whereas the corticosterone concentrations negatively correlated with air temperature, they were positively correlated with the amount of rainfall. The highest air temperature and the amount of rainfall were extracted as the prime factors affecting corticosterone concentrations. These results suggest that cheetahs reared in Japan are somewhat subjected to thermal stress, particularly on cooler and/or rainy days. PMID:24841707

  1. Microbial biogeography of wine grapes is conditioned by cultivar, vintage, and climate.

    PubMed

    Bokulich, Nicholas A; Thorngate, John H; Richardson, Paul M; Mills, David A

    2014-01-01

    Wine grapes present a unique biogeography model, wherein microbial biodiversity patterns across viticultural zones not only answer questions of dispersal and community maintenance, they are also an inherent component of the quality, consumer acceptance, and economic appreciation of a culturally important food product. On their journey from the vineyard to the wine bottle, grapes are transformed to wine through microbial activity, with indisputable consequences for wine quality parameters. Wine grapes harbor a wide range of microbes originating from the surrounding environment, many of which are recognized for their role in grapevine health and wine quality. However, determinants of regional wine characteristics have not been identified, but are frequently assumed to stem from viticultural or geological factors alone. This study used a high-throughput, short-amplicon sequencing approach to demonstrate that regional, site-specific, and grape-variety factors shape the fungal and bacterial consortia inhabiting wine-grape surfaces. Furthermore, these microbial assemblages are correlated to specific climatic features, suggesting a link between vineyard environmental conditions and microbial inhabitation patterns. Taken together, these factors shape the unique microbial inputs to regional wine fermentations, posing the existence of nonrandom "microbial terroir" as a determining factor in regional variation among wine grapes. PMID:24277822

  2. Optimal Deployment of Thermal Energy Storage under Diverse Economic and Climate Conditions

    SciTech Connect

    DeForest, Nicolas; Mendes, Goncalo; Stadler, Michael; Feng, Wei; Lai, Judy; Marnay, Chris

    2014-04-15

    This paper presents an investigation of the economic benefit of thermal energy storage (TES) for cooling, across a range of economic and climate conditions. Chilled water TES systems are simulated for a large office building in four distinct locations, Miami in the U.S.; Lisbon, Portugal; Shanghai, China; and Mumbai, India. Optimal system size and operating schedules are determined using the optimization model DER-CAM, such that total cost, including electricity and amortized capital costs are minimized. The economic impacts of each optimized TES system is then compared to systems sized using a simple heuristic method, which bases system size as fraction (50percent and 100percent) of total on-peak summer cooling loads. Results indicate that TES systems of all sizes can be effective in reducing annual electricity costs (5percent-15percent) and peak electricity consumption (13percent-33percent). The investigation also indentifies a number of criteria which drive TES investment, including low capital costs, electricity tariffs with high power demand charges and prolonged cooling seasons. In locations where these drivers clearly exist, the heuristically sized systems capture much of the value of optimally sized systems; between 60percent and 100percent in terms of net present value. However, in instances where these drivers are less pronounced, the heuristic tends to oversize systems, and optimization becomes crucial to ensure economically beneficial deployment of TES, increasing the net present value of heuristically sized systems by as much as 10 times in some instances.

  3. Opportunities for improving leaf water use efficiency under climate change conditions.

    PubMed

    Gago, Jorge; Douthe, Cyril; Florez-Sarasa, Igor; Escalona, Jose M; Galmes, Jeroni; Fernie, Alisdair R; Flexas, Jaume; Medrano, Hipolito

    2014-09-01

    WUEi (intrinsic water use efficiency) is a complex (multi)-trait, that depends on several physiological processes, driving plant productivity and its relation with a changing environment. Climatic change predictions estimate increases in temperature and drought in the semi-arid regions, rendering improved water use efficiency is a mandatory objective to maintain the current global food supply. The aims of this review were (i) to identify through a meta-analysis the leaf traits mostly related to intrinsic water use efficiency (WUEi, the ratio between A - net photosynthesis and gs - stomatal conductance), based on a newly compiled dataset covering more than 200 species/varieties and 106 genus of C3 plants (ii) to describe the main potential targets for WUEi improvement via biotechnological manipulations and (iii) to introduce emergent and innovative technologies including UAVs (Unmanned Aerial Vehicles) to scale up levels from leaf to whole plant water status. We confirmed that increases in gm/gs and Vcmax/gs ratios are systematically related with increases in WUEi maintained across species, habitats, and environmental conditions. Other emergent opportunities to improve WUEi are described such as the relationship between photosynthesis and respiration and their link with metabolomics. Finally, we outline our hypothesis that we are observing the advent of a "smart" agriculture, wherein new technologies, such as UAVs equipped with remote sensors will rapidly facilitate an efficient water use regulating the irrigation schedule and determination, under field conditions, of cultivars with improved water use efficiency. We, therefore, conclude that the multi-disciplinary challenge toward WUE has only just begun. PMID:25113456

  4. Millennial-scale climate variability in response to changing glacial and orbital boundary conditions during the Mid-Pleistocene transition

    NASA Astrophysics Data System (ADS)

    Ferretti, Patrizia; Crowhurst, Simon; Drysdale, Russell; Bajo, Petra; Barbante, Carlo

    2016-04-01

    The Mid-Pleistocene transition represents perhaps the most important climate transition in the Quaternary period, yet it is one of the most poorly understood. Although the exact timing and mechanism of the onset of the "100 kyr" regime remain a matter of debate, it is well established that the overall periodicity of the glacial-interglacial cycles changed from a dominant 41 kyr obliquity periodicity prior to ~0.9 Ma to a dominant late Pleistocene 100 kyr variance. This change in the frequency domain was associated with an increase in the amplitude of global ice volume variations that, superimposed on a long-term climatic trend towards more glacial conditions over millions of years, produced some of the most extreme glaciations recorded. This interval of time has often been considered to be important in relation to long-term Milankovitch-scale climate variability. In contrast, here, special emphasis will be placed on assessing the presence and the characteristics of the suborbital-scale variability, and reconstructing the evolution of millennial-scale climate variability as the average climate state evolve toward generally colder conditions with larger ice sheets, and the spectral character of climate variability shifted from dominantly 41 kyr to 100 kyr. Appealing evidence suggests that millennial-scale climate variability is amplified during times of intense forcing changes, but this rapid variability has not been thoroughly explored yet at the time when the major changes in climate periodicity occurred. To address these questions, we have examined the record of climatic conditions from Marine Isotope Stages 25 to 16 (~970-650 ka) using high-resolution stable isotope records from benthic and planktonic foraminifera from a sedimentary sequence in the North Atlantic (Integrated Ocean Drilling Program Expedition 306, Site U1313) in order to assess millennial-scale changes in sea-surface and deep-water conditions, the dynamics of thermohaline deep-water circulation

  5. Variation in gene expression of Andropogon gerardii in response to altered environmental conditions associated with climate change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ecological consequences of changes in environmental conditions associated with global climate change will depend in part on how organisms respond to those shifts at the individual level. Currently our understanding of genetic responses of plants to alterations in precipitation and temperature as...

  6. DOE Final Report on Collaborative Research. Quantifying Climate Feedbacks of the Terrestrial Biosphere under Thawing Permafrost Conditions in the Arctic

    SciTech Connect

    Zhuang, Qianlai; Schlosser, C. Adam; Melillo, Jerry M.; Anthony, Katey Walter; Kicklighter, David; Gao, Xiang

    2015-11-03

    Our overall goal is to quantify the potential for threshold changes in natural emission rates of trace gases, particularly methane and carbon dioxide, from pan-arctic terrestrial systems under the spectrum of anthropogenically-forced climate warming, and the conditions under which these emissions provide a strong feedback mechanism to global climate warming. This goal is motivated under the premise that polar amplification of global climate warming will induce widespread thaw and degradation of the permafrost, and would thus cause substantial changes to the landscape of wetlands and lakes, especially thermokarst (thaw) lakes, across the Arctic. Through a suite of numerical experiments that encapsulate the fundamental processes governing methane emissions and carbon exchanges – as well as their coupling to the global climate system - we intend to test the following hypothesis in the proposed research: There exists a climate warming threshold beyond which permafrost degradation becomes widespread and stimulates large increases in methane emissions (via thermokarst lakes and poorly-drained wetland areas upon thawing permafrost along with microbial metabolic responses to higher temperatures) and increases in carbon dioxide emissions from well-drained areas. Besides changes in biogeochemistry, this threshold will also influence global energy dynamics through effects on surface albedo, evapotranspiration and water vapor. These changes would outweigh any increased uptake of carbon (e.g. from peatlands and higher plant photosynthesis) and would result in a strong, positive feedback to global climate warming.

  7. Analysis of induction and establishment of dwarf bunt of wheat under marginal climatic conditions.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dwarf bunt caused by Tilletia contraversa has limited distribution due to essential climatic requirements; primarily persistent snow cover. The pathogen is a quarantine organism in several countries outside of the USA, some of which may have marginal climate for the disease, including the People’s ...

  8. : “Developing Regional Modeling Techniques Applicable for Simulating Future Climate Conditions in the Carolinas”

    EPA Science Inventory

    Global climate models (GCMs) are currently used to obtain information about future changes in the large-scale climate. However, such simulations are typically done at coarse spatial resolutions, with model grid boxes on the order of 100 km on a horizontal side. Therefore, techniq...

  9. SIMULATING REGIONAL-SCALE AIR QUALITY WITH DYNAMIC CHANGES IN REGIONAL CLIMATE AND CHEMICAL BOUNDARY CONDITIONS

    EPA Science Inventory

    This poster compares air quality modeling simulations under current climate and a future (approximately 2050) climate scenario. Differences in predicted ozone episodes and daily average PM2.5 concentrations are presented, along with vertical ozone profiles. Modeling ...

  10. Analysis of induction and establishment of dwarf bunt of wheat under marginal climatic conditions.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dwarf bunt caused by Tilletia contraversa is a disease of winter wheat that has a limited geographic distribution due to specific winter climate requirements. The pathogen is listed as a quarantine organism by several countries that may have wheat production areas with inadequate or marginal climat...

  11. Impact of freshwater release in the North Atlantic under different climate conditions in an OAGCM

    NASA Astrophysics Data System (ADS)

    Swingedouw, Didier; Mignot, Juliette; Braconnot, Pascale; Mosquet, Eloi; Kageyama, Masa; Alkama, Ramdane

    2010-05-01

    The response of climate to freshwater input in the North Atlantic (NA) has raised a lot of concern about the issue of climate stability since the discovery of abrupt coolings during the last glacial period. Such coolings have usually been related to a weakening of the Atlantic meridional overturning circulation (AMOC), probably associated with massive iceberg surges or meltwater pulses. Additionally, the recent increase in greenhouse gases in the atmosphere has also raised the possibility of a melting of the Greenland ice sheet, which may impact the future AMOC, and thereby the climate. In this study, the extent to which the mean climate influences the freshwater release linked to ice sheet melting in the NA and the associated climatic response is explored. For this purpose the simulations of several climatic states (last interglacial, Last Glacial Maximum, mid-Holocene, preindustrial, and future (2×CO2) are considered, and the climatic response to a freshwater input computed interactively according to a surface heat flux budget over the ice sheets is analyzed. It is shown that the AMOC response is not linear with the freshwater input and depends on the mean climate state. The climatic responses to these different AMOC changes share qualitative similarities for the general picture, notably a cooling in the Northern Hemisphere and a southward shift of the intertropical convergence zone (ITCZ) in the Atlantic and across the Panama Isthmus. The cooling in the Northern Hemisphere is related to the sea ice cover response, which strongly depends on the responses of the atmospheric circulation, the local oceanic heat transport, and the density threshold of the oceanic convection sites. These feedbacks and the magnitude of temperature and precipitation changes outside the North Atlantic depend on the mean climate.

  12. Functional evaluation of the field capacity concept for water balance analysis under climatic seasonality conditions

    NASA Astrophysics Data System (ADS)

    Ceres, Francesca; Battista Chirico, Giovanni; Romano, Nunzio

    2010-05-01

    Some types of hydrologic models, such as the bucket model, rely on the concept of field water capacity, θFWC. In this study, the techniques traditionally proposed for determining this parameter have been critically analyzed in terms of their effectiveness in computing soil water budget. Two basic aspects of the problem will be presented: (i) to set up techniques for a suitable parameterization of hydrologic models, (ii) to implement simulation models that describe the various processes with different levels of complexity and compare their results. The following models are considered: the Richards equation based model and the simplified bucket-type model. Soil water content at the condition of field capacity has been determined for both uniform and layered soil profiles by using the numerical model developed by Romano et al. (1998) and verified by Brunone et al. (2003). This model solves the Richards equation with the Crank-Nicolson finite difference technique and uses a numerical algorithm specifically designed in case of layered soils for calculating the hydraulic conductivity at the layer interface. For layered soil profiles, which actually represent the rule rather than an exception, soil layer sequence and the reciprocal differences in the soil hydraulic properties (soil water retention and hydraulic conductivity functions) strongly influence the attainment of the field capacity condition. Simulations of soil water balance using the Richards-based model or the bucket-type model have been compared. It is shown that climatic seasonality typical of the Mediterranean environments exerts some influence on the dynamics of surficial water contents in soil and this influence can be kept only in part by the bucket model if not parameterized adequately. Rainfall variability during the vegetative season and that one evolving during the quiescent phase is responsible for different transpiration conditions and for evolutions of the water content in the soil characterized

  13. Forest management under changing climate conditions: Is timing a tool for Sustainable Forest Management? Relevant questions for research development

    NASA Astrophysics Data System (ADS)

    D'Aprile, Fabrizio; McShane, Paul; Tapper, Nigel

    2013-04-01

    Change of climate conditions influence energy fluxes applicable to forest ecosystems. These affect cycles of nutrients and materials, primary productivity of the ecosystem, biodiversity, ecological functionality and, consequently, carbon equilibria of the forest ecosystem. Temporal factors influence physical, biological, ecological, and climatic processes and functions. For example, seasonality, cycles, periodicity, and trends in climate variables; tree growth, forest growth, and forest metabolic activities (i.e., photosynthesis and respiration) are commonly known to be time-related. In tropical forests, the impacts of changing climate conditions may exceed temperature and/or precipitation thresholds critical to forest tree growth or health. Historically, forest management emphasises growth rates and financial returns as affected by species and site. Until recently, the influence of climate variability on growth dynamics has not been influential in forest planning and management. Under this system, especially in climatic and forest regions where most of species are stenoecious, periodical wood harvesting may occur in any phase of growth (increasing, decreasing, peak, and trough). This scenario presents four main situations: a) harvesting occurs when the rate of growth is decreasing: future productivity is damaged; the minimum biomass capital may be altered, and CO2 storage is negatively affected; b) harvesting occurs during a trough of the rate of growth: the minimum biomass capital necessary to preserve the resilience of the forest is damaged; the damage can be temporary (decades) or permanent; CO2 storage capacity is deficient - which may be read as an indirect emission of CO2 since the balance appears negative; c) harvesting occurs when the rate of growth is increasing: the planned wood mass can be used without compromising the resilience and recovery of the forest; CO2 storage remains increasing; d) harvesting occurs during a peak period of growth: the wood

  14. Human thermal comfort conditions and urban planning in hot-humid climates-The case of Cuba.

    PubMed

    Rodríguez Algeciras, José Abel; Coch, Helena; De la Paz Pérez, Guillermo; Chaos Yeras, Mabel; Matzarakis, Andreas

    2016-08-01

    Climate regional characteristics, urban environmental conditions, and outdoors thermal comfort requirements of residents are important for urban planning. Basic studies of urban microclimate can provide information and useful resources to predict and improve thermal conditions in hot-humid climatic regions. The paper analyzes the thermal bioclimate and its influence as urban design factor in Cuba, using Physiologically Equivalent Temperature (PET). Simulations of wind speed variations and shade conditions were performed to quantify changes in thermal bioclimate due to possible modifications in urban morphology. Climate data from Havana, Camagüey, and Santiago of Cuba for the period 2001 to 2012 were used to calculate PET with the RayMan model. The results show that changes in meteorological parameters influence the urban microclimate, and consequently modify the thermal conditions in outdoors spaces. Shade is the predominant strategy to improve urban microclimate with more significant benefits in terms of PET higher than 30 °C. For climatic regions such as the analyzed ones, human thermal comfort can be improved by a wind speed modification for thresholds of PET above 30 °C, and by a wind speed decreases in conditions below 26 °C. The improvement of human thermal conditions is crucial for urban sustainability. On this regards, our study is a contribution for urban designers, due to the possibility of taking advantage of results for improving microclimatic conditions based on urban forms. The results may enable urban planners to create spaces that people prefer to visit, and also are usable in the reconfiguration of cities. PMID:26628421

  15. Vaccine Adverse Events

    MedlinePlus

    ... Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Vaccines, Blood & Biologics Home Vaccines, Blood & Biologics Safety & Availability ( ... Center for Biologics Evaluation & Research Vaccine Adverse Events Vaccine Adverse Events Share Tweet Linkedin Pin it More ...

  16. Consistency of regional climate projections with the global conditions that stimulated them

    NASA Astrophysics Data System (ADS)

    Sienkiewicz, E. A.; Thompson, E.; Smith, L. A.

    2013-12-01

    Policy decisions related to climate impacts would benefit from robust regional projections if such information was reliable. Regional climate models can be used to add local detail to projections of global climate models. The regional models are usually driven by a global model in a one way fashion: no information from the regional model feeds back into the evolution of the global model which drives it. This research contrasts regional climate variables from a regional climate model with projections for the same region made by the global model driving it. Simulations from the North American Regional Climate Change Assessment Program (NARCCAP) provide a valuable test bed for this type of study. A number of global/regional model pairs are considered with the aim of testing the space and time scales on which the regional model projections remain consistent with the corresponding global model projections. A range of climate variables are considered, to determine criteria for when regional and global models deviate to such an extent that the reliability of both is in question. Differences in quantities like the net surface radiation balance can be related to the size of the climate change drivers expected to generate the signal of interest. For example, comparing the size of the anthropogenic direct radiative forcing with the size of the divergence between net surface radiation balance in the two models provides a useful estimate of the lead time at which the divergence of the two models will have likely swamped any anthropogenic signal. At a lead time of decades, annual averages of important atmospheric variables sometimes reveal a significant divergence between a given regional model and its driving global model. This implies a dynamical noise term that will cloud any physical interpretation of either model. The wider aim of this research is to assess the quality and reliability of climate simulations and the effectiveness of various downscaling methods, in order to

  17. A climate sensitivity test using a global cloud resolving model under an aqua planet condition

    NASA Astrophysics Data System (ADS)

    Miura, Hiroaki; Tomita, Hirofumi; Nasuno, Tomoe; Iga, Shin-ichi; Satoh, Masaki; Matsuno, Taroh

    2005-10-01

    A global Cloud Resolving Model (CRM) is used in a climate sensitivity test for an aqua planet in this first attempt to evaluate climate sensitivity without cumulus parameterizations. Results from a control experiment and an experiment with global sea surface temperature (SST) warmer by 2 K are examined. Notable features in the simulation with warmer SST include a wider region of active convection, a weaker Hadley circulation, mid-tropospheric moistening in the subtropics, and more clouds in the extratropics. Negative feedback from short-wave radiation reduces the climate sensitivity parameter compared to a result in a more conventional model with a cumulus parameterization.

  18. Reverse Engineering Adverse Outcome Pathways

    SciTech Connect

    Perkins, Edward; Chipman, J.K.; Edwards, Stephen; Habib, Tanwir; Falciani, Francesco; Taylor, Ronald C.; Van Aggelen, Graham; Vulpe, Chris; Antczak, Philipp; Loguinov, Alexandre

    2011-01-30

    The toxicological effects of many stressors are mediated through unknown, or poorly characterized, mechanisms of action. We describe the application of reverse engineering complex interaction networks from high dimensional omics data (gene, protein, metabolic, signaling) to characterize adverse outcome pathways (AOPs) for chemicals that disrupt the hypothalamus-pituitary-gonadal endocrine axis in fathead minnows. Gene expression changes in fathead minnow ovaries in response to 7 different chemicals, over different times, doses, and in vivo versus in vitro conditions were captured in a large data set of 868 arrays. We examined potential AOPs of the antiandrogen flutamide using two mutual information theory methods, ARACNE and CLR to infer gene regulatory networks and potential adverse outcome pathways. Representative networks from these studies were used to predict a network path from stressor to adverse outcome as a candidate AOP. The relationship of individual chemicals to an adverse outcome can be determined by following perturbations through the network in response to chemical treatment leading to the nodes associated with the adverse outcome. Identification of candidate pathways allows for formation of testable hypotheses about key biologic processes, biomarkers or alternative endpoints, which could be used to monitor an adverse outcome pathway. Finally, we identify the unique challenges facing the application of this approach in ecotoxicology, and attempt to provide a road map for the utilization of these tools. Key Words: mechanism of action, toxicology, microarray, network inference

  19. The role of vegetation for tropospheric ozone balance: possible changes under future climate conditions

    NASA Astrophysics Data System (ADS)

    Wu, Cheng; Pullinen, Iida; Andres, Stefanie; Carriero, Giulia; Fares, Silvano; Hacker, Lina; Kiendler-Scharr, Astrid; Kleist, Einhard; Paoletti, Elena; Wahner, Andreas; Wildt, Jürgen; Mentel, Thomas F.

    2015-04-01

    Ozone (O3) is a phytotoxic trace gas in the troposphere where it is photochemically produced from volatile organic compounds (VOCs) and nitrogen oxides (NOx). The dominant sink of O3 in the air over areas with dense plant cover is dry deposition on plant surfaces. However, plants can also contribute to photochemical O3 formation because they emit biogenic VOCs (BVOCs). In this study, the role of vegetation for tropospheric ozone balance was investigated by considering the following processes: O3 depletion by dry deposition on plant surfaces, O3 depletion by gas phase reactions with plant emitted BVOCs, and photochemical O3 production from these BVOCs. Furthermore, drought and heat stress were applied to the plants, and the stress-induced changes of plant performance and the subsequent changes regarding the tropospheric ozone balance were investigated. Dry deposition of O3 in unstressed plants was dominated by O3 uptake through the plants stomata with negligible losses on cuticle and stem. For strong BVOC emitters, O3 destruction by gas phase reactions with BVOCs was significant at low NOx conditions. Switching from low NOx to high NOx conditions led to O3 production. A ratio of O3 formation rates over BVOC loss rates was measured for α-pinene as single BVOC and for BVOC mixtures emitted from real plants. For O3 formation under BVOC limited conditions, this ratio was in the range of 2-3 ppb/ppb. The ratio of O3 uptake/BVOC emission reflects the capability of a plant as a potential source of O3, while NOx concentrations and the BVOC/NOx ratio determine whether the emitted BVOCs act as an additional sink or a source of O3. O3 uptake rates and BVOC emission rates are affected by environmental variables such as temperature, light intensity and stresses to plants. The impacts of these variables on the two processes are different and thus the capability of a plant to be a source of O3 is also affected. As future climate change will bring more and intense heat waves and

  20. The effect of cultivation practices on soil - atmosphere carbon cycle under arid climate conditions

    NASA Astrophysics Data System (ADS)

    Lifschitz, David; Sternberg, Marcelo; Bonfil, David; Ben-Dor, Eyal; Eshel, Gil

    2010-05-01

    The soil - atmosphere carbon cycle was studied under arid climate conditions, in relation to crop management. Management included different tillage (Conventional vs. No Tillage, CT vs. NT respectively) and fertilization (nitrogen and phosphorus application vs. unfertilized) practices, in a continuous (winter) wheat field, for two growing seasons (2007-08 and 2008-09). The NT practice was characterized by higher CO2 effluxes than the CT during the growing season. In turn, the CT practice had higher pCO2 throughout the soil profile to a depth of 2m. This could be explained partially by a physical crust formation due to raindrop impact, emerging on the bare soil, mostly in the CT practice. The crust serves as a barrier for gas exchange (soil aeration) and in addition, also reduces rainfall infiltration, and all together harms the growing potential (the NT practice yielded higher plant biomass). Fertilization application had no apparent effect on the CO2 effluxes or the pCO2, but had a significant effect on the yield of the plant biomass. The NT practice had also higher amounts of soil organic Carbon, (SOC) mainly in the surface layer, and soil inorganic Carbon (SIC) to a depth of 2m. This is attributed to straw mulch application for the former and better gas and water conductivity (that initiates carbonate dissolution - precipitation cycles) for the latter, which is a much more dominant factor in arid area soils. The stable carbon isotope analysis (δ13C) values for the total Carbon (TC), SOC and SIC results show that the NT practice generates higher amounts of pedogenic carbonates also, and in general is clearly superior over CT in almost every aspect in the soil - atmosphere C cycle.

  1. Experimental evaluation of insecticidal paints against Triatoma infestans (Hemiptera: Reduviidae), under natural climatic conditions

    PubMed Central

    Amelotti, Ivana; Catalá, Silvia S; Gorla, David E

    2009-01-01

    Background Triatoma infestans is the main vector of Chagas disease in the Gran Chaco region of South America. The traditional spraying technique used for the application of pyrethroid insecticides has shown low efficiency in the elimination of the vector species populations occupying peridomestic structures of rural houses in the endemic area of Argentina. As part of studies looking for better alternatives, we evaluated the residual effect of insecticidal paints on the mortality of fourth instar nymphs of T. infestans. Results The study was based on an experimental design that included two groups treated with an organophosphate (Inesfly 5A IGR™) and a pyrethroid (Inesfly 5A IGR NG™) formulations of the paint, that were applied on wood, cement blocks and adobe bricks under natural climatic conditions. A third group was an untreated control. Both paint formulations showed very long residual activity, producing mortality of 84% and 98% (pyrethroid and organophosphate formulations, respectively) after 12 months of the paint application. After eight months, nymphs exposed during 6 hours to the painted surfaces with the pyrethroid and organophosphate formulations showed 81.33% and 100% mortality, respectively. Conclusion The organophosphate- and pyrethroid-based insecticidal paints showed a very long residual activity on the mortality of fourth instar nymphs of T infestans, compared with the traditional spraying technique used for the application of pyrethroid insecticides in peridomestic structures of rural houses in the endemic region for Chagas disease in the Gran Chaco of Argentina. The application of the paints by trained personnel of the vector control programmes could be considered as an alternative control tool in areas where the traditional methods have failed or showed low efficacy. PMID:19586532

  2. Carbon dynamics of two adjacent temperate forests under similar climatic conditions

    NASA Astrophysics Data System (ADS)

    Malla Thakuri, B.; Kim, J.

    2012-12-01

    The proximity (< 1.5 km) of the two KoFlux towers (i.e., Gwangneung coniferous forest site, GCK and deciduous forest site, GDK) provides an excellent opportunity to study carbon dynamics of the two different plant functional types under similar climate and environmental conditions. We have analyzed the CO2 flux data measured by eddy covariance from 2007 to 2010 at GCK and GDK sites. Our objectives were (1) to compare and contrast the seasonality and inter-annual variability in net ecosystem CO2 exchange (NEE) of the two adjacent forests and (2) to interpret their carbon dynamics in the framework of resilience concept. The multi-year measurements of CO2 fluxes at both sites showed contrasting inter-annual trends. Overall, both the annual gross primary productivity (GPP) and ecosystem respiration (RE) were higher for GCK site with an average NEE of -220 (±137) g C m-2 yr-1 while that of GDK was -67 (±58) g C m-2 yr-1. The GCK showed a continuous, threefold increase in NEE with lower water use efficiency whereas the GDK fluctuated between carbon source and weak to moderate carbon sink. Each year, both sites manifested a mid-season depression in GPP (and thus NEE), which was more pronounced at GCK. On a seasonal basis, summer was the most productive for GDK while spring for GCK. The results are interpreted in terms of phenology and different stages of adaptive cycles. Acknowledgment This work was funded by the Korea Meteorological Administration Research and Development Program under Grant CATER 2012-3030.

  3. Vegetation types and climate conditions reflected by the modern phytolith assemblages in the subalpine Dalaoling Forest Reserve, central China

    NASA Astrophysics Data System (ADS)

    Traoré, Djakanibé Désiré; Gu, Yansheng; Liu, Humei; Shemsanga, Ceven; Ge, Jiwen

    2015-06-01

    This research describes modern phytolith records and distributions from subalpine surface soils in the Dalaoling Forest Reserve, and reveals its implications for local climate conditions with respect to the altitude gradient. Well-preserved phytolith morpho-types, assemblages, and climatic indices were used to study the relationship between local vegetation and climate conditions. The phytolith classification system is mainly based on the characteristics of detailed morpho-types described for anatomical terms, which are divided into seven groups: long cells, short cells, bulliform cells, hair cells, pteridophyte type, broad-leaved type, and gymnosperm type. Phytoliths originating from the Poaceae are composed of Pooideae (rondel and trapeziform), Panicoideae (bilobate, cross, and polylobate), Chloridoideae (short/square saddle), and Bambusoideae (oblong concave saddle). Based on the altitudinal distribution of the phytolith assemblages and the indices of aridity (Iph), climate (Ic), and tree cover density (D/P), five phytolith assemblage zones have revealed the five types of climatic conditions ranging from 1,169 m to 2,005 m in turn: warm-wet, warm-xeric to warm-mesic, warm-xeric to cool-mesic, cool-xeric, and cool-mesic to cool-xeric. The Bambusoideae, Panicoideae, and Chloridoideae are the dominant vegetation at the lower-middle of the mountains, while Pooideae is mainly distributed in the higher mountains. The close relationship between phytolith assembleages and changes of altitude gradient suggest that vegetation distribution patterns and plant ecology in the Dalaoling mountains are controlled by temperature and humidity conditions. Our results highlight the importance of phytolith records as reliable ecoclimatic indicators for vegetation ecology in subtropical regions.

  4. Migration, neighborhoods, and networks: approaches to understanding how urban environmental conditions affect syndemic adverse health outcomes among gay, bisexual and other men who have sex with men.

    PubMed

    Egan, James E; Frye, Victoria; Kurtz, Steven P; Latkin, Carl; Chen, Minxing; Tobin, Karin; Yang, Cui; Koblin, Beryl A

    2011-04-01

    Adopting socioecological, intersectionality, and lifecourse theoretical frameworks may enhance our understanding of the production of syndemic adverse health outcomes among gay, bisexual and other men who have sex with men (MSM). From this perspective, we present preliminary data from three related studies that suggest ways in which social contexts may influence the health of MSM. The first study, using cross-sectional data, looked at migration of MSM to the gay resort area of South Florida, and found that amount of time lived in the area was associated with risk behaviors and HIV infection. The second study, using qualitative interviews, observed complex interactions between neighborhood-level social environments and individual-level racial and sexual identity among MSM in New York City. The third study, using egocentric network analysis with a sample of African American MSM in Baltimore, found that sexual partners were more likely to be found through face-to-face means than the Internet. They also observed that those who co-resided with a sex partner had larger networks of people to depend on for social and financial support, but had the same size sexual networks as those who did not live with a partner. Overall, these findings suggest the need for further investigation into the role of macro-level social forces on the emotional, behavioral, and physical health of urban MSM. PMID:21369730

  5. Migration, Neighborhoods, and Networks: Approaches to Understanding How Urban Environmental Conditions Affect Syndemic Adverse Health Outcomes Among Gay, Bisexual and Other Men Who Have Sex with Men

    PubMed Central

    Egan, James E.; Kurtz, Steven P.; Latkin, Carl; Chen, Minxing; Tobin, Karin; Yang, Cui; Koblin, Beryl A.

    2011-01-01

    Adopting socioecological, intersectionality, and lifecourse theoretical frameworks may enhance our understanding of the production of syndemic adverse health outcomes among gay, bisexual and other men who have sex with men (MSM). From this perspective, we present preliminary data from three related studies that suggest ways in which social contexts may influence the health of MSM. The first study, using cross-sectional data, looked at migration of MSM to the gay resort area of South Florida, and found that amount of time lived in the area was associated with risk behaviors and HIV infection. The second study, using qualitative interviews, observed complex interactions between neighborhood-level social environments and individual-level racial and sexual identity among MSM in New York City. The third study, using egocentric network analysis with a sample of African American MSM in Baltimore, found that sexual partners were more likely to be found through face-to-face means than the Internet. They also observed that those who co-resided with a sex partner had larger networks of people to depend on for social and financial support, but had the same size sexual networks as those who did not live with a partner. Overall, these findings suggest the need for further investigation into the role of macro-level social forces on the emotional, behavioral, and physical health of urban MSM. PMID:21369730

  6. Interpopulational Variations in Sexual Chemical Signals of Iberian Wall Lizards May Allow Maximizing Signal Efficiency under Different Climatic Conditions

    PubMed Central

    2015-01-01

    Sexual signals used in intraspecific communication are expected to evolve to maximize efficacy under a given climatic condition. Thus, chemical secretions of lizards might evolve in the evolutionary time to ensure that signals are perfectly tuned to local humidity and temperature conditions affecting their volatility and therefore their persistence and transmission through the environment. We tested experimentally whether interpopulational altitudinal differences in chemical composition of femoral gland secretions of male Iberian wall lizards (Podarcis hispanicus) have evolved to maximize efficacy of chemical signals in different environmental conditions. Chemical analyses first showed that the characteristics of chemical signals of male lizards differed between two populations inhabiting environments with different climatic conditions in spite of the fact that these two populations are closely related genetically. We also examined experimentally whether the temporal attenuation of the chemical stimuli depended on simulated climatic conditions. Thus, we used tongue-flick essays to test whether female lizards were able to detect male scent marks maintained under different conditions of temperature and humidity by chemosensory cues alone. Chemosensory tests showed that chemical signals of males had a lower efficacy (i.e. detectability and persistence) when temperature and dryness increase, but that these effects were more detrimental for signals of the highest elevation population, which occupies naturally colder and more humid environments. We suggest that the abiotic environment may cause a selective pressure on the form and expression of sexual chemical signals. Therefore, interpopulational differences in chemical profiles of femoral secretions of male P. hispanicus lizards may reflect adaptation to maximize the efficacy of the chemical signal in different climates. PMID:26121693

  7. Rainfall Downscaling Conditional on Upper-air Atmospheric Predictors: Improved Assessment of Rainfall Statistics in a Changing Climate

    NASA Astrophysics Data System (ADS)

    Langousis, Andreas; Mamalakis, Antonis; Deidda, Roberto; Marrocu, Marino

    2015-04-01

    To improve the level skill of Global Climate Models (GCMs) and Regional Climate Models (RCMs) in reproducing the statistics of rainfall at a basin level and at hydrologically relevant temporal scales (e.g. daily), two types of statistical approaches have been suggested. One is the statistical correction of climate model rainfall outputs using historical series of precipitation. The other is the use of stochastic models of rainfall to conditionally simulate precipitation series, based on large-scale atmospheric predictors produced by climate models (e.g. geopotential height, relative vorticity, divergence, mean sea level pressure). The latter approach, usually referred to as statistical rainfall downscaling, aims at reproducing the statistical character of rainfall, while accounting for the effects of large-scale atmospheric circulation (and, therefore, climate forcing) on rainfall statistics. While promising, statistical rainfall downscaling has not attracted much attention in recent years, since the suggested approaches involved complex (i.e. subjective or computationally intense) identification procedures of the local weather, in addition to demonstrating limited success in reproducing several statistical features of rainfall, such as seasonal variations, the distributions of dry and wet spell lengths, the distribution of the mean rainfall intensity inside wet periods, and the distribution of rainfall extremes. In an effort to remedy those shortcomings, Langousis and Kaleris (2014) developed a statistical framework for simulation of daily rainfall intensities conditional on upper air variables, which accurately reproduces the statistical character of rainfall at multiple time-scales. Here, we study the relative performance of: a) quantile-quantile (Q-Q) correction of climate model rainfall products, and b) the statistical downscaling scheme of Langousis and Kaleris (2014), in reproducing the statistical structure of rainfall, as well as rainfall extremes, at a

  8. Seasonal activity patterns of Ixodes pacificus nymphs in relation to climatic conditions.

    PubMed

    Eisen, L; Eisen, R J; Lane, R S

    2002-09-01

    In western North America, the tick Ixodes pacificus Cooley & Kohls (Acari: Ixodidae) is the primary vector to humans and domestic animals of the disease agents causing Lyme disease and granulocytic ehrlichiosis. We examined the seasonal activity patterns of I. pacificus nymphs over a 4-year period, including the wet and cold El Niño winter/spring of 1998, in a dry oak/madrone woodland, and for one year in a cooler and moister redwood/tanoak woodland in Mendocino County, California. Linear regressions were used to estimate when nymphal densities first exceeded and then fell below 25, 50 and 75% of the recorded yearly peak densities. In oak/madrone woodland, nymphs typically were active by mid-March, reached 50% of their yearly peak densities in early to mid-April, peaked by early May, fell below 50% of their peak densities by early to mid-June, and were absent by late July to mid-August. The lengths of the periods with nymphal densities exceeding 50 and 75% of the recorded yearly peaks in oak/madrone woodland were associated positively with rainfall and negatively with maximum air temperatures during April-May. Moreover, nymphal numbers typically reached 50% of their peak 10-15 days later, remained at levels above 50% of the peak 1.3-1.5 times longer, and started declining 4-6 weeks later under cooler, moister climatic conditions (oak/madrone woodland in 1998 and redwood/tanoak woodland in 2000) relative to warmer, drier conditions (oak/madrone woodland in 2000-2001). In oak/madrone woodland, nymphal densities typically started to decline when mean maximum daily air temperatures exceeded 23 degrees C. Nymphal densities were higher in dry oak/madrone relative to moist redwood/tanoak woodland from mid-March to late May 2000, similar in both habitat types in early June, but higher in redwood/tanoak woodland from late June onwards. We conclude that large-scale studies of the density of I. pacificus nymphs in California need to consider spatial variation in the length

  9. Certain questions of the acclimatization of construction workers to the conditions of a subtropical climate

    NASA Technical Reports Server (NTRS)

    Babayev, A.

    1979-01-01

    The period of active acclimatization was determined for construction workers coming into a subtropical climate. Changes were observed in metabolic processes, oxygen needs, pulse rate, arterial pressure, body and skin temperature, body weight, water consumption and loss, and the comfort zone of heat sensitivity. It was concluded that acclimatization is facilitated if introduction to the hot climate occurs in the mild cool season, rather than the summer. This also prevents heat prostration and improves the development of adaptive mechanisms.

  10. Prediction of soil and ground water contamination with fungicides of different classes according to soil and climate conditions in Ukrain and other European countries.

    PubMed

    Vavrinevych, O; Antonenko, A; Omelchuk, S; Korshun, M; Bardov, V

    2015-05-01

    It was established that most of tested pesticides are moderately and low persistent in soil and climatic conditions of Ukraine, but more stable in Western and Northern Europe countries due to peculiarities of their climate type and soil characteristics. In addition, it was determined that all studied fungicides pertain to non- and low mobile compound (except moderately mobile pyrimethanil). Recommendations on application of studied fungicides in soil and climatic conditions of Ukraine and other European countries were given. PMID:26042452

  11. Catchment scale modelling of changes in pesticide leaching under present and future climate conditions. Demonstrated for two cases in Denmark

    NASA Astrophysics Data System (ADS)

    van der Keur, P.; Henriksen, H.; Sonnenborg, T.; van Roosmalen, L.; Rosenbom, A. E.; Olesen, J. E.; Kjaer, J.; Jørgensen, L. N.; Christensen, O. B.

    2011-12-01

    A catchment scale model MACRO-MIKE SHE is applied for simulating changes in pesticide concentrations to the aquatic environment. The MACRO model is used to model the effect of changes in climate and pesticide management on pesticide leaching from the unsaturated zone and simulated percolation as well as solute flow is propagated to the MIKE SHE model. The intensity based bias correction method for converting from Regional Climate Modelling data to hydrological input data is the most appropriate method as it best reflects changes in rainfall intensity, and thus also in intensity for MACRO simulated percolation and solute flow. Results show that increased percolation simulated by the MACRO model and propagated to the MIKE SHE model nearly all ends up in increased drainage to the river. Further, pesticide solute entering the saturated zone (SZ) is mainly leaving SZ via drainage (85-94%), base flow (3.8-11.3%) and overland flow (0-3.1 %). Mean concentrations in groundwater (SZ) increase by 30-99% for one type of herbicide under future climatic conditions, whereas mean concentrations decrease for two other types by app. 93 and 91 % respectively. Future climatic conditions lead to higher concentrations in surface water for the first type of herbicides, but to decreased concentrations for the another type of herbicide and insecticide. It is overall concluded that an integrated catchment scale modeling approach is essential for pesticide fate simulation taking account of all possible hydrologic pathways.

  12. Different effects of an extended photoperiod treatment on growth, gonadal function, and condition of hair coats in Thoroughbred yearlings reared under different climate conditions

    PubMed Central

    SUZUKI, Tsuyoshi; MIZUKAMI, Hirotoshi; NAMBO, Yasuo; ISHIMARU, Mutsuki; MIYATA, Kenji; AKIYAMA, Kentaro; KOROSUE, Kenji; NAITO, Hiroshi; NAGAOKA, Kentaro; WATANABE, Gen; TAYA, Kazuyoshi

    2016-01-01

    ABSTRACT One- to two-year-old Thoroughbred colts and fillies being reared in Miyazaki (warm climate) and Hidaka (cold climate), Japan, were administered extended photoperiod (EP) treatment between December 20 and the following April 10, and its effect on growth, endocrine changes, gonadal activation, and hair coat condition was investigated. In colts reared in Miyazaki, no effect of EP treatment was noted on the growth indices, including body weight (BW), height at withers (HW), girth, and cannon circumference (CC), whereas the BWs and CCs of fillies were significantly higher in the EP treatment group than the control. In Hidaka, the BWs and HWs of colts and HWs of fillies were significantly higher in the EP treatment group. Gonadal activation characterized by an increase in circulating hormone concentrations was earlier in the EP treatment group for fillies reared in Miyazaki [luteinizing hormone (LH), follicle-stimulating hormone (FSH), progesterone (P4), and estradiol-17β (E2)] and in colts (LH, testosterone, and E2) and fillies (LH, FSH, P4, and E2) reared in Hidaka. Regardless of sex and climate, prolactin was significantly higher in the EP treatment group, whereas insulin-like growth factor (IGF-I) was not. Initial ovulation occurred before April in more of the EP treatment group than the control regardless of the climate. Molting of the hair coat, examined in March, was advanced in the EP treatment group regardless of sex and climate. These results suggest that EP treatment may promote growth and gonadal activation in fillies reared in Miyazaki and in colts and fillies reared in Hidaka and that the effect may be mediated by prolactin. PMID:26858576

  13. Different effects of an extended photoperiod treatment on growth, gonadal function, and condition of hair coats in Thoroughbred yearlings reared under different climate conditions.

    PubMed

    Suzuki, Tsuyoshi; Mizukami, Hirotoshi; Nambo, Yasuo; Ishimaru, Mutsuki; Miyata, Kenji; Akiyama, Kentaro; Korosue, Kenji; Naito, Hiroshi; Nagaoka, Kentaro; Watanabe, Gen; Taya, Kazuyoshi

    2015-01-01

    One- to two-year-old Thoroughbred colts and fillies being reared in Miyazaki (warm climate) and Hidaka (cold climate), Japan, were administered extended photoperiod (EP) treatment between December 20 and the following April 10, and its effect on growth, endocrine changes, gonadal activation, and hair coat condition was investigated. In colts reared in Miyazaki, no effect of EP treatment was noted on the growth indices, including body weight (BW), height at withers (HW), girth, and cannon circumference (CC), whereas the BWs and CCs of fillies were significantly higher in the EP treatment group than the control. In Hidaka, the BWs and HWs of colts and HWs of fillies were significantly higher in the EP treatment group. Gonadal activation characterized by an increase in circulating hormone concentrations was earlier in the EP treatment group for fillies reared in Miyazaki [luteinizing hormone (LH), follicle-stimulating hormone (FSH), progesterone (P4), and estradiol-17β (E2)] and in colts (LH, testosterone, and E2) and fillies (LH, FSH, P4, and E2) reared in Hidaka. Regardless of sex and climate, prolactin was significantly higher in the EP treatment group, whereas insulin-like growth factor (IGF-I) was not. Initial ovulation occurred before April in more of the EP treatment group than the control regardless of the climate. Molting of the hair coat, examined in March, was advanced in the EP treatment group regardless of sex and climate. These results suggest that EP treatment may promote growth and gonadal activation in fillies reared in Miyazaki and in colts and fillies reared in Hidaka and that the effect may be mediated by prolactin. PMID:26858576

  14. Seasonal variability of hydro-physical conditions in Faxinal system subtropical climate in southern Brazil.

    NASA Astrophysics Data System (ADS)

    Antoneli, Valdemir; Thomaz, Edivaldo; Berdnaz, João

    2015-04-01

    , and 46.1 cm / h in Native Forest. The infiltration in the secondary forest in January was of 32.3 cm / h (29.9% higher than in August). The pasture indicated infiltration of 12.8 cm / h (32.9% lower) and 49.2 cm / h native forest (6.3% higher). Soil compaction in August was of 2.9 kgf / cm2 in the secondary forest, 3.7 kgf / cm2 in the pasture, and 1.4 kgf / cm2 in the Native Forest. In January, compression was of 2.1 in Secondary Forest (27.6% less than in August), 4.0 kgf / cm2 in the pasture (7.5% higher) and 1.3 kgf / cm2 in the native Forest (7.1% lower). These variations may be associated to the climatic conditions which cause some frost in winter promoting greater mobilization of animals looking for food in secondary forest areas due to reduced pasture. The springs from the pasture in summer enhances the time animals stay in the pasture areas. The influence of animals on hydrogeomorphic conditions in faxinal areas was evident, especially when comparing the data from the two areas with the ones indicated by the Native Forest.

  15. Severe Loss of Suitable Climatic Conditions for Marsupial Species in Brazil: Challenges and Opportunities for Conservation

    PubMed Central

    Loyola, Rafael D.; Lemes, Priscila; Faleiro, Frederico V.; Trindade-Filho, Joaquim; Machado, Ricardo B.

    2012-01-01

    A wide range of evidences indicate climate change as one the greatest threats to biodiversity in the 21st century. The impacts of these changes, which may have already resulted in several recent species extinction, are species-specific and produce shifts in species phenology, ecological interactions, and geographical distributions. Here we used cutting-edge methods of species distribution models combining thousands of model projections to generate a complete and comprehensive ensemble of forecasts that shows the likely impacts of climate change in the distribution of all 55 marsupial species that occur in Brazil. Consensus projections forecasted range shifts that culminate with high species richness in the southeast of Brazil, both for the current time and for 2050. Most species had a significant range contraction and lost climate space. Turnover rates were relatively high, but vary across the country. We also mapped sites retaining climatic suitability. They can be found in all Brazilian biomes, especially in the pampas region, in the southern part of the Brazilian Atlantic Forest, in the north of the Cerrado and Caatinga, and in the northwest of the Amazon. Our results provide a general overview on the likely effects of global climate change on the distribution of marsupials in the country as well as in the patterns of species richness and turnover found in regional marsupial assemblages. PMID:23029452

  16. Severe loss of suitable climatic conditions for marsupial species in Brazil: challenges and opportunities for conservation.

    PubMed

    Loyola, Rafael D; Lemes, Priscila; Faleiro, Frederico V; Trindade-Filho, Joaquim; Machado, Ricardo B

    2012-01-01

    A wide range of evidences indicate climate change as one the greatest threats to biodiversity in the 21st century. The impacts of these changes, which may have already resulted in several recent species extinction, are species-specific and produce shifts in species phenology, ecological interactions, and geographical distributions. Here we used cutting-edge methods of species distribution models combining thousands of model projections to generate a complete and comprehensive ensemble of forecasts that shows the likely impacts of climate change in the distribution of all 55 marsupial species that occur in Brazil. Consensus projections forecasted range shifts that culminate with high species richness in the southeast of Brazil, both for the current time and for 2050. Most species had a significant range contraction and lost climate space. Turnover rates were relatively high, but vary across the country. We also mapped sites retaining climatic suitability. They can be found in all Brazilian biomes, especially in the pampas region, in the southern part of the Brazilian Atlantic Forest, in the north of the Cerrado and Caatinga, and in the northwest of the Amazon. Our results provide a general overview on the likely effects of global climate change on the distribution of marsupials in the country as well as in the patterns of species richness and turnover found in regional marsupial assemblages. PMID:23029452

  17. Computations on frost damage to Scots pine under climatic warming in boreal conditions

    SciTech Connect

    Kellomaeki, S.; Haenninen, H.; Kolstroem, M.

    1995-02-01

    To investigate the risk of frost damage to Scots pine (Pinus sylvestris L.) in northern regions under climatic warming, a submodel for such damage to trees was included in a forest ecosystem model of the gap type. An annual growth multiplier describing the effects of frost was calculated with the help of simulated daily frost hardiness and daily minimum temperature. The annual growth multiplier was used in the main ecosystem model when simulating the development of a tree stand using a time step of one year. Simulations of the growth and development of Scots pine stands in southern Finland (61{degrees} N) under an elevating temperature indicated that climatic warming could increase the risk of frost damage due to premature onset of growth during warm spells in the late winter and early spring. Risk of frost damage implies uncertainty in yield expectations from boreal forest ecosystems in the event of climatic warming. 38 refs., 9 figs., 4 tabs.

  18. Relating variations in runoff to variations in climatic conditions and catchment properties

    NASA Astrophysics Data System (ADS)

    Farquhar, Graham; Sun, Fubao; Roderick, Michael

    2013-04-01

    We use the Budyko framework to calculate catchment-scale evapotranspiration (E)and runoff (Q) as a function of two climatic factors, precipitation (P) and evaporative demand (Eo = 0.75 times the pan evaporation rate), and a third parameter that encodes the catchment properties (n) and modifies how P is partitioned between E and Q. We use examples from the Murray-Darling Basin in Australia, and elsewhere, to examine the effects on run-off of perturbations to the underlying parameters. We include an examination of projections based on Intergovernmental Panel on Climate Change AR4 climate model output. We conclude that the modern version of the Budyko framework is a useful tool for making simple and transparent estimates of changes in water availability.

  19. Patterns of wildfires and emissions under future climate conditions across the conterminous United States

    NASA Astrophysics Data System (ADS)

    Hawbaker, T. J.; Zhu, Z.; Finney, M.; Riley, K. L.; Jolly, W. M.; Keane, R. E.; Reinhardt, E.

    2013-12-01

    Climate change is expected to result in increased wildfire occurrence and greenhouse gas emissions in the conterminous United States. To better understand potential changes and their impacts, we asked: How might such expected changes vary over space and time in the conterminous United States, and across different climate-change scenarios? We quantified baseline patterns of burned area and emissions using burn scars from 2001-2008. Then, we developed a simulation model to assess the influence of climate change on patterns of wildfire ignitions, spread, and emissions. The simulation model was calibrated using historic fire, weather, and climate data and then used to generate projections under the A1B, A2, and B1 climate-change scenarios. We defined typical fire years and extreme fire years as the 50th and 95th percentile of decadal area burned or emissions. Then, we evaluated simulated changes in burned area and emissions among the 2001-2010 and 2041-2050 decades. Across the conterminous United States, our simulations results showed that during a typical fire year, area burned increased 25-52% from 15,700 km2 and emissions increased 20-48% from a baseline level of 56.0 TgCO2-eq. Extreme fire years in the 2041-2050 decade were more extreme than in the baseline period, and area burned increased 65-85% from 31,700 km2 and emissions increased 49-142% from 92.7 TgCO2-eq. Projected changes in fire occurrence and emissions were minimal for the Great Plains, but substantial for the West and certain ecoregions in the East. These results suggest that future wildfire activities could play a larger role in terms of socioeconomic risks and the health and productivity of ecosystems, and that efforts designed to reduce greenhouse gas emissions will compete with potential carbon losses due to climate-driven increases in wildfire occurrence.

  20. Sensitivity of global river discharges under Holocene and future climate conditions

    NASA Astrophysics Data System (ADS)

    Aerts, J. C. J. H.; Renssen, H.; Ward, P. J.; de Moel, H.; Odada, E.; Bouwer, L. M.; Goosse, H.

    2006-10-01

    A comparative analysis of global river basins shows that some river discharges are more sensitive to future climate change for the coming century than to natural climate variability over the last 9000 years. In these basins (Ganges, Mekong, Volta, Congo, Amazon, Murray-Darling, Rhine, Oder, Yukon) future discharges increase by 6-61%. These changes are of similar magnitude to changes over the last 9000 years. Some rivers (Nile, Syr Darya) experienced strong reductions in discharge over the last 9000 years (17-56%), but show much smaller responses to future warming. The simulation results for the last 9000 years are validated with independent proxy data.

  1. Characteristic of blocking events over Siberia for the present and future climate conditions, and the implications for the regional climate in South China

    NASA Astrophysics Data System (ADS)

    Cheung, H.; Zhou, W.

    2010-12-01

    Blocking activity over Siberia is a crucial factor for initiating and maintaining severe cold events in East Asia, but limited studies have provided a detailed analysis on the impact of its changing characteristics on the regional climate, especially in South China. By using 60-year NCEP-NCAR Reanalysis Datasets (1950/51-2009/10), where a winter season is defined as the 151/152 day period from Nov 1 to Mar 31, distinct characteristics of the blocking events and their downstream impacts for the present climate conditions can be assessed thoroughly. It is found that the blocking events persisting east of the Ural Mountains are generally followed by a cold air outbreak sweeping across various parts in East Asia. Specifically, the intense blocking events usually have large extension and they potentially result in persistent cold weather within the region. On the other hand, the blocking events west of the Ural Mountains are found to exert an impact only if it is of long duration and high intensity. The cold air pathways may be dependent on the geographic location of the blocking anticyclone. The active blocking season over the Urals is probably associated with more intense cold events extending southward and eastward to a great extent. On the contrary, the cold events in the winters of high blocking activity east and west of the Urals are often confined to the northern region. The preferred blocking location may be related to the wavetrain signal propagating eastward from the North Atlantic Ocean. Long-term variability of blocking activities shows a remarkable decreasing and weakening trend. This is perhaps reflected by a similar trend of the cold events in East Asia. Energetic and dynamical factors that are favorable and unfavorable for a specific blocking character will be explored. The explanation is accompanied with the simulation results of future climate conditions using the IPCC AR4 model outputs. The analysis is particularly valuable for enhancing the

  2. Response and adaptation of grapevine cultivars to hydrological conditions forced by a changing climate in a complex landscape

    NASA Astrophysics Data System (ADS)

    De Lorenzi, Francesca; Bonfante, Antonello; Alfieri, Silvia Maria; Monaco, Eugenia; De Mascellis, Roberto; Manna, Piero; Menenti, Massimo

    2014-05-01

    requirements were determined. To assess cultivars adaptability, hydrological requirements were evaluated against hydrological indicators. A probabilistic assessment of adaptability was performed, and the inaccuracy of estimated hydrological requirements was accounted for by the error of estimate and its distribution. Maps of cultivars potential distribution, i.e. locations where each cultivar is expected to be compatible with climate, were derived and possible options for adaptation to climate change were defined. The 2021 - 2050 climate scenario was characterized by higher temperatures throughout the year and by a significant decrease in precipitation during spring and autumn. The results have shown the relevant variability of soils water regime and its effects on cultivars adaptability. In the future climate scenario, a hydrological indicator (i.e. relative evapotranspiration deficit - RETD), averaged over the growing season, showed an average increase of 5-8 %, and more pronounced increases occurred in the phenological phases of berry formation and ripening. At the locations where soil hydrological conditions were favourable (like the ancient terraces), hydrological indicators were quite similar in both climate scenarios and the adaptability of the cultivars was high both in the reference and future climate case. The work was carried out within the Italian national project AGROSCENARI funded by the Ministry for Agricultural, Food and Forest Policies (MIPAAF, D.M. 8608/7303/2008) Keywords: climate change, Vitis vinifera L., simulation model, yield response functions, potential cultivation area.

  3. Wear of surface-engineered metal-on-metal bearings for hip prostheses under adverse conditions with the head loading on the rim of the cup.

    PubMed

    Leslie, Ian; Williams, Sophie; Isaac, Graham; Hatto, Peter; Ingham, Eileen; Fisher, John

    2013-04-01

    Clinical studies have found high wear rates, elevated ion levels and high revision rates of large-diameter metal-on-metal surface replacement bearings in some patients, which have been associated with edge loading of the head on the rim of the cup. We have simulated increased wear and ion levels in metal-on-metal bearings in vitro by introducing variations in translational and rotational positioning of the components, which reproduces stripe wear on the femoral head, cup rim wear and clinically relevant large as well as small wear particles. There is interest in technologies such as surface engineering, which might reduce metal wear and the release of wear particles and ions. Reduced wear with surface-engineered surface replacements compared to metal-on-metal controls has been reported under standard walking conditions with correctly aligned and concentric components. In this in vitro study, the wear of chromium nitride surface-engineered metal-on-metal bearings under conditions of microseparation associated with translational and rotational malpositioning of the components was investigated and the results were compared with a previously reported study of metal-on-metal bearings under the same conditions. Simulations were conducted using our unique hip simulation microseparation methodologies, which reproduce accelerated wear in metal-on-metal bearings and have previously been clinically validated with ceramic-on-ceramic bearings. Four of the six surface-engineered bearings had evidence of head contact on the rim of the cup, which produced stripe wear on the femoral head. Four of the six surface-engineered bearings (two without stripe and two with stripe wear) had lower wear than the previously reported high wearing metal-on-metal bearings. At 2 million cycles, two of the surface-engineered bearings had substantially increased wear rates, four times higher than the high wear rates previously reported for metal-on-metal bearings under the same conditions. There was

  4. ADVERSE CUTANEOUS DRUG REACTION

    PubMed Central

    Nayak, Surajit; Acharjya, Basanti

    2008-01-01

    In everyday clinical practice, almost all physicians come across many instances of suspected adverse cutaneous drug reactions (ACDR) in different forms. Although such cutaneous reactions are common, comprehensive information regarding their incidence, severity and ultimate health effects are often not available as many cases go unreported. It is also a fact that in the present world, almost everyday a new drug enters market; therefore, a chance of a new drug reaction manifesting somewhere in some form in any corner of world is unknown or unreported. Although many a times, presentation is too trivial and benign, the early identification of the condition and identifying the culprit drug and omit it at earliest holds the keystone in management and prevention of a more severe drug rash. Therefore, not only the dermatologists, but all practicing physicians should be familiar with these conditions to diagnose them early and to be prepared to handle them adequately. However, we all know it is most challenging and practically difficult when patient is on multiple medicines because of myriad clinical symptoms, poorly understood multiple mechanisms of drug-host interaction, relative paucity of laboratory testing that is available for any definitive and confirmatory drug-specific testing. Therefore, in practice, the diagnosis of ACDR is purely based on clinical judgment. In this discussion, we will be primarily focusing on pathomechanism and approach to reach a diagnosis, which is the vital pillar to manage any case of ACDR. PMID:19967009

  5. Relating El Nino-Southern oscillation climate conditions to irrigation strategies for increased cotton yield

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The global-scale El Nino–Southern Oscillation (ENSO) of sea surface temperature that causes monsoonal rain in India also affects precipitation in North America.The ENSO phases and related rain expectations have been used to limit climate uncertainties when producing wheat for grazing and grain. Insi...

  6. Assessing Students' Learning about Fundamental Concepts of Climate Change under Two Different Conditions

    ERIC Educational Resources Information Center

    Porter, Dianna; Weaver, Andrew J.; Raptis, Helen

    2012-01-01

    Students from three different British Columbia grade six classes were followed through two weeks of instruction on climate change. Pre, post, and follow-up surveys were used to determine the differences in knowledge gained and retained by students that received direct instruction from their science teacher, and by those who received equivalent…

  7. Vegetation productivity responds to sub-annual climate conditions across semiarid biomes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the Southwestern United States (SW), the current prolonged warm drought is similar to the predicted future climate change scenarios for the region. This study aimed to determine patterns in vegetation response to the early 21st century drought across multiple biomes. We hypothesized that differen...

  8. Statistical modelling of grapevine yield in the Port Wine region under present and future climate conditions

    NASA Astrophysics Data System (ADS)

    Santos, João A.; Malheiro, Aureliano C.; Karremann, Melanie K.; Pinto, Joaquim G.

    2011-03-01

    The impact of projected climate change on wine production was analysed for the Demarcated Region of Douro, Portugal. A statistical grapevine yield model (GYM) was developed using climate parameters as predictors. Statistically significant correlations were identified between annual yield and monthly mean temperatures and monthly precipitation totals during the growing cycle. These atmospheric factors control grapevine yield in the region, with the GYM explaining 50.4% of the total variance in the yield time series in recent decades. Anomalously high March rainfall (during budburst, shoot and inflorescence development) favours yield, as well as anomalously high temperatures and low precipitation amounts in May and June (May: flowering and June: berry development). The GYM was applied to a regional climate model output, which was shown to realistically reproduce the GYM predictors. Finally, using ensemble simulations under the A1B emission scenario, projections for GYM-derived yield in the Douro Region, and for the whole of the twenty-first century, were analysed. A slight upward trend in yield is projected to occur until about 2050, followed by a steep and continuous increase until the end of the twenty-first century, when yield is projected to be about 800 kg/ha above current values. While this estimate is based on meteorological parameters alone, changes due to elevated CO2 may further enhance this effect. In spite of the associated uncertainties, it can be stated that projected climate change may significantly benefit wine yield in the Douro Valley.

  9. A simple framework for relating variations in runoff to variations in climatic conditions and catchment properties

    NASA Astrophysics Data System (ADS)

    Roderick, Michael L.; Farquhar, Graham D.

    2011-12-01

    We use the Budyko framework to calculate catchment-scale evapotranspiration (E) and runoff (Q) as a function of two climatic factors, precipitation (P) and evaporative demand (Eo = 0.75 times the pan evaporation rate), and a third parameter that encodes the catchment properties (n) and modifies how P is partitioned between E and Q. This simple theory accurately predicted the long-term evapotranspiration (E) and runoff (Q) for the Murray-Darling Basin (MDB) in southeast Australia. We extend the theory by developing a simple and novel analytical expression for the effects on E and Q of small perturbations in P, Eo, and n. The theory predicts that a 10% change in P, with all else constant, would result in a 26% change in Q in the MDB. Future climate scenarios (2070-2099) derived using Intergovernmental Panel on Climate Change AR4 climate model output highlight the diversity of projections for P (±30%) with a correspondingly large range in projections for Q (±80%) in the MDB. We conclude with a qualitative description about the impact of changes in catchment properties on water availability and focus on the interaction between vegetation change, increasing atmospheric [CO2], and fire frequency. We conclude that the modern version of the Budyko framework is a useful tool for making simple and transparent estimates of changes in water availability.

  10. Seawater intrusion risk analysis under climate change conditions for the Gaza Strip aquifer (Palestine)

    NASA Astrophysics Data System (ADS)

    Dentoni, Marta; Deidda, Roberto; Paniconi, Claudio; Marrocu, Marino; Lecca, Giuditta

    2014-05-01

    Seawater intrusion (SWI) has become a major threat to coastal freshwater resources, particularly in the Mediterranean basin, where this problem is exacerbated by the lack of appropriate groundwater resources management and with serious potential impacts from projected climate changes. A proper analysis and risk assessment that includes climate scenarios is essential for the design of water management measures to mitigate the environmental and socio-economic impacts of SWI. In this study a methodology for SWI risk analysis in coastal aquifers is developed and applied to the Gaza Strip coastal aquifer in Palestine. The method is based on the origin-pathway-target model, evaluating the final value of SWI risk by applying the overlay principle to the hazard map (representing the origin of SWI), the vulnerability map (representing the pathway of groundwater flow) and the elements map (representing the target of SWI). Results indicate the important role of groundwater simulation in SWI risk assessment and illustrate how mitigation measures can be developed according to predefined criteria to arrive at quantifiable expected benefits. Keywords: Climate change, coastal aquifer, seawater intrusion, risk analysis, simulation/optimization model. Acknowledgements. The study is partially funded by the project "Climate Induced Changes on the Hydrology of Mediterranean Basins (CLIMB)", FP7-ENV-2009-1, GA 244151.

  11. Modeling hydrological regimes of lakes under climate change conditions using heat-water balance method by Budyko

    NASA Astrophysics Data System (ADS)

    Lemeshko, Natalia; Eitzinger, Josef; Kubu, Gerhard

    2013-04-01

    Global climate change will lead to increasing air temperatures over the next decades and is expected at least to be 1-2°C above the pre-industrial values in near future. Close relationships between the physical processes in the atmosphere and the surface of the planet cause not only temperature changes, but also changes in other parameters of the climate system including hydrosphere. In this context the investigations of a possible change in moisture regime with global warming are very important for assessment of the future changes in the hydrological cycle. A steady-state hydrological model has been developed for evaluation of the changes in climate and hydrological parameters with the progress of global warming. This model is based on the heat-water balance method by M. Budyko and paleoclimatic scenarios. The Budyko's heat-water balance method is based on the combined solution of energy and water balance equations, as well as two empirical dependences: the evaporation rate on soil water content and the surface runoff on precipitation and soil moisture. This method is a universal one as it was developed using empirical data of different climates, including specific humid and arid ones. The method allows to calculate the mean monthly values of evaporation, runoff and water content of the active soil layer (1 m) using data on mean monthly values of surface air temperature, air humidity, precipitation, cloudiness, surface albedo and solar radiation, both for the actual climatic conditions, and for climatic conditions different from the present ones. Some additional assumptions have been made to adapt the method for scenarios of climate change. The paleoclimate scenarios are considered to a certain extent as analogs of future climates. The scenarios used consist of regional deviation from actual climate of annual precipitation, winter and summer air temperatures for Holocene optimum (6-5 KA B.P.) and Last Interglacial (about 125 KA B.P.), which correspond to global

  12. Basin-scale simulation of current and potential climate changed hydrologic conditions in the Lake Michigan Basin, United States

    USGS Publications Warehouse

    Christiansen, Daniel E.; Walker, John F.; Hunt, Randall J.

    2014-01-01

    The Great Lakes Restoration Initiative (GLRI) is the largest public investment in the Great Lakes in two decades. A task force of 11 Federal agencies developed an action plan to implement the initiative. The U.S. Department of the Interior was one of the 11 agencies that entered into an interagency agreement with the U.S. Environmental Protection Agency as part of the GLRI to complete scientific projects throughout the Great Lakes basin. The U.S. Geological Survey, a bureau within the Department of the Interior, is involved in the GLRI to provide scientific support to management decisions as well as measure progress of the Great Lakes basin restoration efforts. This report presents basin-scale simulated current and forecast climatic and hydrologic conditions in the Lake Michigan Basin. The forecasts were obtained by constructing and calibrating a Precipitation-Runoff Modeling System (PRMS) model of the Lake Michigan Basin; the PRMS model was calibrated using the parameter estimation and uncertainty analysis (PEST) software suite. The calibrated model was used to evaluate potential responses to climate change by using four simulated carbon emission scenarios from eight general circulation models released by the World Climate Research Programme’s Coupled Model Intercomparison Project phase 3. Statistically downscaled datasets of these scenarios were used to project hydrologic response for the Lake Michigan Basin. In general, most of the observation sites in the Lake Michigan Basin indicated slight increases in annual streamflow in response to future climate change scenarios. Monthly streamflows indicated a general shift from the current (2014) winter-storage/snowmelt-pulse system to a system with a more equally distributed hydrograph throughout the year. Simulated soil moisture within the basin illustrates that conditions within the basin are also expected to change on a monthly timescale. One effect of increasing air temperature as a result of the changing

  13. Under what conditions do climate-driven sex ratios enhance versus diminish population persistence?

    PubMed Central

    Boyle, Maria; Hone, Jim; Schwanz, Lisa E; Georges, Arthur

    2014-01-01

    For many species of reptile, crucial demographic parameters such as embryonic survival and individual sex (male or female) depend on ambient temperature during incubation. While much has been made of the role of climate on offspring sex ratios in species with temperature-dependent sex determination (TSD), the impact of variable sex ratio on populations is likely to depend on how limiting male numbers are to female fecundity in female-biased populations, and whether a climatic effect on embryonic survival overwhelms or interacts with sex ratio. To examine the sensitivity of populations to these interacting factors, we developed a generalized model to explore the effects of embryonic survival, hatchling sex ratio, and the interaction between these, on population size and persistence while varying the levels of male limitation. Populations with TSD reached a greater maximum number of females compared to populations with GSD, although this was often associated with a narrower range of persistence. When survival depended on temperature, TSD populations persisted over a greater range of temperatures than GSD populations. This benefit of TSD was greatly reduced by even modest male limitation, indicating very strong importance of this largely unmeasured biologic factor. Finally, when males were not limiting, a steep relationship between sex ratio and temperature favoured population persistence across a wider range of climates compared to the shallower relationships. The opposite was true when males were limiting – shallow relationships between sex ratio and temperature allowed greater persistence. The results highlight that, if we are to predict the response of populations with TSD to climate change, it is imperative to 1) accurately quantify the extent to which male abundance limits female fecundity, and 2) measure how sex ratios and peak survival coincide over climate. PMID:25512848

  14. Simulating the vegetation response in western Europe to abrupt climate changes under glacial background conditions

    NASA Astrophysics Data System (ADS)

    Woillez, M.-N.; Kageyama, M.; Combourieu-Nebout, N.; Krinner, G.

    2013-03-01

    The last glacial period has been punctuated by two types of abrupt climatic events, the Dansgaard-Oeschger (DO) and Heinrich (HE) events. These events, recorded in Greenland ice and in marine sediments, involved changes in the Atlantic Meridional Overturning Circulation (AMOC) and led to major changes in the terrestrial biosphere. Here we use the dynamical global vegetation model ORCHIDEE to simulate the response of vegetation to abrupt changes in the AMOC strength. We force ORCHIDEE offline with outputs from the IPSL_CM4 general circulation model, in which the AMOC is forced to change by adding freshwater fluxes in the North Atlantic. We investigate the impact of a collapse and recovery of the AMOC, at different rates, and focus on Western Europe, where many pollen records are available for comparison. The impact of an AMOC collapse on the European mean temperatures and precipitations simulated by the GCM is relatively small but sufficient to drive an important regression of forests and expansion of grasses in ORCHIDEE, in qualitative agreement with pollen data for an HE event. On the contrary, a run with a rapid shift of the AMOC to a hyperactive state of 30 Sv, mimicking the warming phase of a DO event, does not exhibit a strong impact on the European vegetation compared to the glacial control state. For our model, simulating the impact of an HE event thus appears easier than simulating the abrupt transition towards the interstadial phase of a DO. For both a collapse or a recovery of the AMOC, the vegetation starts to respond to climatic changes immediately but reaches equilibrium about 200 yr after the climate equilibrates, suggesting a possible bias in the climatic reconstructions based on pollen records, which assume equilibrium between climate and vegetation. However, our study does not take into account vegetation feedbacks on the atmosphere.

  15. Projecting supply and demand of hydrologic ecosystem services under future climate conditions

    NASA Astrophysics Data System (ADS)

    Chiang, Li-Chi; Huang, Tao; Lee, Tsung-Yu

    2014-05-01

    Ecosystems provide essential goods and services, such as food, clean water, water purification, soil conservation and cultural services for human being. In a watershed, these water-related ecosystem goods and services can directly or indirectly benefit both local people and downstream beneficiaries through a reservoir. Water quality and quantity in a reservoir are of importance for agricultural, industrial and domestic uses. Under the impacts of climate and land use changes, both ecosystem service supply and demand will be affected by changes in precipitation patterns, temperature, urbanization and agricultural activities. However, the linkage between ecosystem service provisioning (ESP) and ecosystem service beneficiary (ESB), and scales of supply and demand of ecosystem services are not clear yet. Therefore, to investigate water-related ecosystem service supply under climate and land use change, we took the Xindian river watershed (303 km2) as a case study, where the Feitsui Reservoir provides hydro-power and daily domestic water use of 3,450,000 m3 for 3.46 million people in Taipei, Taiwan. We integrated a hydrological model (Soil and Water Assessment Tool, SWAT) and a land use change model (Conversion of Land Use and its Effects, CLUE-s) with future climate change scenarios derived from General Circulation Models (GCMs), to assess the changes in ecosystem service supply and demand at different hydrologic scales. The results will provide useful information for decision-making on future land use management and climate change adaptation strategies in the watersheds. Keywords: climate change, land use change, ecosystem service, watershed, scale

  16. Working with invalid boundary conditions: lessons from the field for communicating about climate change with public audiences

    NASA Astrophysics Data System (ADS)

    Gunther, A.

    2015-12-01

    There is an ongoing need to communicate with public audiences about climate science, current and projected impacts, the importance of reducing greenhouse gas emissions, and the requirement to prepare for changes that are likely unavoidable. It is essential that scientists are engaged and active in this effort. Scientists can be more effective communicators about climate change to non-scientific audiences if we recognize that some of the normal "boundary conditions" under which we operate do not need to apply. From how we are trained to how we think about our audience, there are some specific skills and practices that allow us to be more effective communicators. The author will review concepts for making our communication more effective based upon his experience from over 60 presentations about climate change to public audiences. These include expressing how your knowledge makes you feel, anticipating (and accepting) questions unconstrained by physics, respecting beliefs and values while separating them from evidence, and using the history of climate science to provide a compelling narrative. Proper attention to presentation structure (particularly an opening statement), speaking techniques for audience engagement, and effective use of presentation software are also important.

  17. Selecting Populations for Non-Analogous Climate Conditions Using Universal Response Functions: The Case of Douglas-Fir in Central Europe.

    PubMed

    Chakraborty, Debojyoti; Wang, Tongli; Andre, Konrad; Konnert, Monika; Lexer, Manfred J; Matulla, Christoph; Schueler, Silvio

    2015-01-01

    Identifying populations within tree species potentially adapted to future climatic conditions is an important requirement for reforestation and assisted migration programmes. Such populations can be identified either by empirical response functions based on correlations of quantitative traits with climate variables or by climate envelope models that compare the climate of seed sources and potential growing areas. In the present study, we analyzed the intraspecific variation in climate growth response of Douglas-fir planted within the non-analogous climate conditions of Central and continental Europe. With data from 50 common garden trials, we developed Universal Response Functions (URF) for tree height and mean basal area and compared the growth performance of the selected best performing populations with that of populations identified through a climate envelope approach. Climate variables of the trial location were found to be stronger predictors of growth performance than climate variables of the population origin. Although the precipitation regime of the population sources varied strongly none of the precipitation related climate variables of population origin was found to be significant within the models. Overall, the URFs explained more than 88% of variation in growth performance. Populations identified by the URF models originate from western Cascades and coastal areas of Washington and Oregon and show significantly higher growth performance than populations identified by the climate envelope approach under both current and climate change scenarios. The URFs predict decreasing growth performance at low and middle elevations of the case study area, but increasing growth performance on high elevation sites. Our analysis suggests that population recommendations based on empirical approaches should be preferred and population selections by climate envelope models without considering climatic constrains of growth performance should be carefully appraised before

  18. Selecting Populations for Non-Analogous Climate Conditions Using Universal Response Functions: The Case of Douglas-Fir in Central Europe

    PubMed Central

    Chakraborty, Debojyoti; Wang, Tongli; Andre, Konrad; Konnert, Monika; Lexer, Manfred J.; Matulla, Christoph; Schueler, Silvio

    2015-01-01

    Identifying populations within tree species potentially adapted to future climatic conditions is an important requirement for reforestation and assisted migration programmes. Such populations can be identified either by empirical response functions based on correlations of quantitative traits with climate variables or by climate envelope models that compare the climate of seed sources and potential growing areas. In the present study, we analyzed the intraspecific variation in climate growth response of Douglas-fir planted within the non-analogous climate conditions of Central and continental Europe. With data from 50 common garden trials, we developed Universal Response Functions (URF) for tree height and mean basal area and compared the growth performance of the selected best performing populations with that of populations identified through a climate envelope approach. Climate variables of the trial location were found to be stronger predictors of growth performance than climate variables of the population origin. Although the precipitation regime of the population sources varied strongly none of the precipitation related climate variables of population origin was found to be significant within the models. Overall, the URFs explained more than 88% of variation in growth performance. Populations identified by the URF models originate from western Cascades and coastal areas of Washington and Oregon and show significantly higher growth performance than populations identified by the climate envelope approach under both current and climate change scenarios. The URFs predict decreasing growth performance at low and middle elevations of the case study area, but increasing growth performance on high elevation sites. Our analysis suggests that population recommendations based on empirical approaches should be preferred and population selections by climate envelope models without considering climatic constrains of growth performance should be carefully appraised before

  19. How do climate and human impact affect Sphagnum peatlands under oceanic-continental climatic conditions? 2000 years of fire and hydrological history of a bog in Northern Poland

    NASA Astrophysics Data System (ADS)

    Marcisz, Katarzyna; Tinner, Willy; Colombaroli, Daniele; Kołaczek, Piotr; Słowiński, Michał; Fiałkiewicz-Kozieł, Barbara; Lamentowicz, Mariusz

    2014-05-01

    Climate change affects many natural processes and the same applies to human impact For instance climate change and anthropogenic activities may cause increased fire activity or change peatland dynamics. Currently it is still unknown how Sphagnum peatlands in the oceanic-continental transition zone of Poland may respond to combined effects of heat waves, drought and fire. The aim of the study was to reconstruct the last 2000 years palaeohydrology and fire history at Linje bog in Northern Poland. The main task was to determine the drivers of fire episodes, particularly to identify climatic and anthropogenic forcing. A two-meter peat core was extracted and subsampled with a high resolution. Micro- and macroscopic charcoal analyses were applied to determine past fire activity and the results compared with palaeohydrological reconstructions based on testate amoeba analysis. Palynological human indicators were used to reconstruct human activity. A depth-age model including 20 14C dates was constructed to calculate peat accumulation rates and charcoal influx. We hypothesised that: 1) fire frequency in Northern Poland was determined by climatic conditions (combination of low precipitation and heat waves), as reflected in peatland water table, and that 2) past fire episodes in the last millennium were intensified by human activity. Furthermore climate may have influenced human activity over harvest success and the carrying capacity. Our study shows that fire was important for the studied ecosystem, however, its frequency has increased in the last millennium in concomitance with land use activities. Landscape humanization and vegetation opening were followed by a peatland drying during the Little Ice Age (from ca. AD 1380). Similarly to other palaeoecological studies from Poland, Linje peatland possessed an unstable hydrology during the Little Ice Age. Increased fire episodes appeared shortly before the Little Ice Age and most severe fires were present in the time when

  20. Rapid and persistent change of microbial community and gross N turnover under experimentally simulated climate change conditions in alpine grassland

    NASA Astrophysics Data System (ADS)

    Wang, Changhui; Chen, Zhe; Unteregelsbacher, Sebastian; Gschwendtner, Silvia; Schloter, Michael; Butterbach-Bahl, Klaus; Dannenmann, Michael

    2013-04-01

    Alpine grasslands of Central Europe are exposed to strong warming and to altered precipitation patterns, suggesting that ecosystem nitrogen (N) cycling may be vulnerable to future climatic conditions. In order to investigate the response of soil microbial community and N transformations to predicted climate change conditions, we conducted an ecosystem manipulation experiment following the "space for time" approach in the TERENO (Terrestrial Environmental Observatories) pre-alpine grassland observatory. For this purpose, we dislocated 200 mini-lysimeters containing intact plant-soil systems down an altitudinal gradient from 860m to 550m above sea level, with corresponding control transfers within the high altitude site. After an equilibration period of 2.5 years, a full annual cycle of gross rates of N turnover as well as microbial biomass- and -community dynamics was monitored based on 15 sampling dates in two soil layers. For the monitored year, simulation of climate change via lysimeter transfer had increased mean annual soil temperature in 5 cm depth on average by 2.4 °C, but on the other hand promoted soil frost in winter due to reduced snow cover. Soil moisture was decreased on average by 20%. Gross N turnover and the abundance of N cycle genes in soil were characterized by pronounced seasonal dynamics, with both summer and winter representing key periods for the annual sum of N turnover. The abundance of ammonia oxidizing archae (AOA) genes exceeded the abundance of ammonia oxidizing bacterial (AOB) genes by approximately three orders of magnitude. Climate change simulation strongly increased the abundance of both AOB and AOA gene copies in soil, consistent with an increase of annual gross nitrification rates by 41%. Gross N mineralization was even increased by 141% in the climate change treatment. The abundance of AOA genes in soil explained 80% of the variability of gross nitrification rates over the full annual course. These results provide strong

  1. What Climate Conditions Enhance Hillslope Erosion in Semi-Arid Regions?

    NASA Astrophysics Data System (ADS)

    Pierce, J. L.; Riley, K. E.; Kenworthy, M.; Poulos, M. J.; Weppner, K.; Nelson, N.; Svenson, L.

    2011-12-01

    Researchers have long pondered the question of how climate and climate change influence rates and processes of erosion: this question has become more relevant in the face of ongoing and future anthropogenic warming. We examine evidence of hillslope erosion and sedimentation on alluvial fans over Holocene and Quaternary timescales throughout a range of ecosystems in Idaho, USA. Records of erosion include fire-related and non-fire related deposition on alluvial fans, and landscape-scale analysis of hillslope slope angles. Over Holocene timescales, five independent records of forest-fires and fire-related erosion from sagebrush steppe, pinion-juniper, ponderosa pine, lodgepole pine and mixed conifer ecosystems indicate that sedimentation rates and processes on alluvial fans vary temporally with Holocene climate and spatially with vegetation type. Despite variations in ecosystem type and associated fire regimes, all sites show similar broad-scale temporal patterns. The mid-Holocene (~4-8 ka) is characterized by few fire-related deposits and many non-fire related sheetflooding events (vs. debris flows); this relatively fire-free interval is punctuated by fire peaks and associated sheetflooding ~7-6 ka. As regional paleoclimatic reconstructions generally indicate this time was generally warm and dry the lack of fire is somewhat counterintuitive; however, decreased fuel loads, combined with perhaps a more stable climate may reduce fire and storm intensity and frequency. Late Holocene (last ~3 ka) cooler, wetter and more variable climates (as compared to the mid-Holocene) are characterized by increased fire activity at all sites, and more large debris flows. Medieval droughts correspond with major fire and debris flow peaks ~1000-800 cal yr BP; decadal to annual droughts during the generally cooler and wetter LIA also promote fire peaks ~500-300 cal yr BP. Modern observations of hillslope erosion indicate north-facing or moister slopes are characterized by dense vegetation

  2. Pre-Emergency-Department Care-Seeking Patterns Are Associated with the Severity of Presenting Condition for Emergency Department Visit and Subsequent Adverse Events: A Timeframe Episode Analysis

    PubMed Central

    Yang, Nan-Ping; Lai, K. Robert; Huang, Hsin-Tsung

    2015-01-01

    Background Many patients treated in Emergency Department (ED) visits can be treated at primary or urgent care sectors, despite the fact that a number of ED visitors seek other forms of care prior to an ED visit. However, little is known regarding how the pre-ED activity episodes affect ED visits. Objectives We investigated whether care-seeking patterns involve the use of health care services of various types prior to ED visits and examined the associations of these patterns with the severity of the presenting condition for the ED visit (EDVS) and subsequent events. Methods This retrospective observational study used administrative data on beneficiaries of the universal health care insurance program in Taiwan. The service type, treatment capacity, and relative diagnosis were used to classify pre-ED visits into 8 care types. Frequent pattern analysis was used to identify sequential care-seeking patterns and to classify 667,183 eligible pre-ED episodes into patterns. Generalized linear models were developed using generalized estimating equations to examine the associations of these patterns with EDVS and subsequent events. Results The results revealed 17 care-seeking patterns. The EDVS and likelihood of subsequent events significantly differed among patterns. The ED severity index of patterns differ from patterns seeking directly ED care (coefficients ranged from -0.05 to 0.13), and the odds-ratios for the likelihood of subsequent ED visits and hospitalization ranged from 1.18 to 1.86 and 1.16 to 2.84, respectively. Conclusions The pre-ED care-seeking patterns differ in severity of presenting condition and subsequent events that may represent different causes of ED visit. Future health policy maker may adopt different intervention strategies for targeted population to reduce unnecessary ED visit effectively. PMID:26030278

  3. Renewable energy to develop adaptation strategies to the climate change conditions

    NASA Astrophysics Data System (ADS)

    Servadio, Pieranna; Bergonzoli, Simone

    2013-04-01

    between the corn rows. During the irrigation tests for the autoclave pressure values already mentioned, we obtained an 80 l min-1 flow rate value with a 28 m head value measured by pressure gauge upstream from the electric pump. In these conditions and on sunny days a 26 m3 water body was obtained. From the agronomic point of view, the crop developed more than usual, did not undergo parasite attack nor lodging or cutting off of the steams during the biological cycle, and the development of weeds was limited. The grain production amounted to 10.5 t ha-1, 12.4 % higher with respect to the rain-irrigated parcels. Crop yield results showed better performance of the drip irrigation plant with respect to the sprinkler system. The photovoltaic system met design expectations and showed good reliability during the years of testing. The long-term tests showed that the photovoltaic system is capable of supplying a farm. The problem linked with combustion of fossil fuel will improve this system of energy supply to agricultural farms located in areas not reached by the power network both in Europe and in the sub Saharan countries where many plans are developing in last year pursuing also the scope of a drastic reduction of GHG fluxes. Acknowledgements This work was carried out under the auspices of the special project "Sceneries of adaptation of the Italian agriculture to the climatic changes" (AGROSCENARI) of the Agricultural Research Council, and Italian Ministry of the Agricultural and Forestry Politics.

  4. Northward displacement of optimal climate conditions for ecotypes of Eriophorum vaginatum L. across a latitudinal gradient in Alaska.

    PubMed

    McGraw, James B; Turner, Jessica B; Souther, Sara; Bennington, Cynthia C; Vavrek, Milan C; Shaver, Gaius R; Fetcher, Ned

    2015-10-01

    Plants are often genetically specialized as ecotypes attuned to local environmental conditions. When conditions change, the optimal environment may be physically displaced from the local population, unless dispersal or in situ evolution keep pace, resulting in a phenomenon called adaptational lag. Using a 30-year-old reciprocal transplant study across a 475 km latitudinal gradient, we tested the adaptational lag hypothesis by measuring both short-term (tiller population growth rates) and long-term (17-year survival) fitness components of Eriophorum vaginatum ecotypes in Alaska, where climate change may have already displaced the optimum. Analyzing the transplant study as a climate transfer experiment, we showed that the climate optimum for plant performance was displaced ca. 140 km north of home sites, although plants were not generally declining in size at home sites. Adaptational lag is expected to be widespread globally for long-lived, ecotypically specialized plants, with disruptive consequences for communities and ecosystems. PMID:26033529

  5. Short-Term Relationship between Hip Fracture and Weather Conditions in Two Spanish Health Areas with Different Climates

    PubMed Central

    Tenías, José María; Estarlich, Marisa; Crespo, Eusebio; Román-Ortiz, Carmen; Arias-Arias, Angel; Ballester, Ferran

    2015-01-01

    Objective. To evaluate differences in the short-term relationship between weather conditions and the incidence of hip fracture in people aged 65 and over among two regions of Spain. Methods. Hip fracture incidence was calculated for the years 2000–2008 for residents of Health Area 14 in Valencian Community (Mediterranean climate) and the “Mancha Centro” Health Area in Castilla-La Mancha (inland climate), Spain. The relationship between hip fracture incidence and weather was analyzed with a case-crossover design and explored in subgroups defined by sex, age, and fracture type. Results. In the inland area, a positive and significant tendency for hip fracture incidence was observed (annual increase: 1.5%) whereas in the Mediterranean area a seasonal increase of 9% was noted in autumn and winter with respect to spring. Weather conditions, especially wind, were significantly associated with hip fracture incidence: days with more frequent windy periods and/or a greater wind velocity were associated with an increase in hip fracture incidence of 51% in the Mediterranean area and 44% in the inland area. Conclusions. Hip fracture incidence exhibits seasonal changes that differ between the Mediterranean and inland areas. The short-term relationship with climate, although similar in both areas, may partly explain these seasonal changes. PMID:25759722

  6. A coupled Bayesian and fault tree methodology to assess future groundwater conditions in light of climate change

    NASA Astrophysics Data System (ADS)

    Huang, J. J.; Du, M.; McBean, E. A.; Wang, H.; Wang, J.

    2014-08-01

    Maintaining acceptable groundwater levels, particularly in arid areas, while protecting ecosystems, are key measures against desertification. Due to complicated hydrological processes and their inherent uncertainties, investigations of groundwater recharge conditions are challenging, particularly in arid areas under climate changing conditions. To assist planning to protect against desertification, a fault tree methodology, in conjunction with fuzzy logic and Bayesian data mining, are applied to Minqin Oasis, a highly vulnerable regime in northern China. A set of risk factors is employed within the fault tree framework, with fuzzy logic translating qualitative risk data into probabilities. Bayesian data mining is used to quantify the contribution of each risk factor to the final aggregated risk. The implications of both historical and future climate trends are employed for temperature, precipitation and potential evapotranspiration (PET) to assess water table changes under various future scenarios. The findings indicate that water table levels will continue to drop at the rate of 0.6 m yr-1 in the future when climatic effects alone are considered, if agricultural and industrial production capacity remain at 2004 levels.

  7. Response of ice cover on shallow Arctic lakes to contemporary climate conditions: Numerical modeling and remote sensing data analysis

    NASA Astrophysics Data System (ADS)

    Duguay, C.; Surdu, C.; Brown, L.; Samuelsson, P.

    2012-04-01

    Lake ice cover has been shown to be a robust indicator of climate variability and change. Recent studies have demonstrated that break-up dates, in particular, have been occurring earlier in many parts of the Northern Hemisphere over the last 50 years in response to warmer climatic conditions in the winter and spring seasons. The impacts of trends in air temperature and winter precipitation over the last five decades and those projected by global climate models will affect the timing and duration of ice cover (and ice thickness) on Arctic lakes. This will likely, in turn, have an important feedback effect on energy, water, and biogeochemical cycling in various regions of the Arctic. In the case of shallow tundra lakes, many of which are less than 3-m deep, warmer climate conditions could result in a smaller fraction of lakes that freeze to their bed in winter since thinner ice covers are expected to develop. Shallow lakes of the coastal plain of northern Alaska, and other similar regions of the Arctic, have likely been experiencing changes in seasonal ice thickness (and phenology) over the last few decades but these have not yet been documented. This paper presents results from a numerical lake ice modeling experiment and the analysis of ERS-1/2 synthetic aperture radar (SAR) data to elucidate the response of ice cover (thickness, freezing to bed, and phenology) on shallow lakes of the North Slope of Alaska (NSA)to climate conditions over the last three decades. New downscaled data specific for the Arctic domain (at a resolution of 0.44 degrees using ERA Interim Reanalysis as boundary condition) produced by the Rossby Centre regional atmospheric model (RCA4) was used to force the Canadian Lake Ice Model (CLIMo) for the period 1979-2010. Output from CLIMo included freeze-up and break-up dates as well as ice thickness on a daily basis. ERS-1/2 data was used to map areas of shallow lakes that freeze to bed and when this happens (timing) in winter for the period 1991

  8. The Climate Effects of Deforestation the Amazon Rainforest under Global Warming Conditions

    NASA Astrophysics Data System (ADS)

    Werth, D.; Avissar, R.

    2006-12-01

    Replacement of tropical rainforests has been observed to have a strong drying effect in Amazon simulations, with effects reaching high into the atmospheric column and into the midlatitudes. The drying effects of deforestation, however, can be moderated by the effects of global warming, which should accelerate the hydrologic cycle of the Amazon. The effects of a prescribed, time-varying Amazon deforestation done in conjunction with a steady, moderate increase in CO2 concentrations are determined using a climate model. The model agrees with previous studies when each forcing is applied individually - compared to a control run, Amazon deforestation decreases the local precipitation and global warming increases it. When both are applied, however, the precipitation and other hydrologic variables decrease, but to a lesser extent than when deforestation alone was applied. In effect, the two effects act opposite to one another and bring the simulated climate closer to that of the control.

  9. A natural resource condition assessment for Sequoia and Kings Canyon National Parks: Appendix 22: climatic change

    USGS Publications Warehouse

    Das, Adrian J.; Stephenson, Nathan L.

    2013-01-01

    30-year time periods -- the Independence station, with a relatively continuous temperature record starting in 1925 -- shows a modest warming, not a cooling, between 1925-1940 and 1971-2000, further casting doubt on the Kings Canyon cooling shown in Figs. 6 and 11 of Appendix 1. If funds become available, it will be useful to more formally analyze potential PRISM biases in long-term SEKI climatic trends. Until then, the analyses of individual weather station records

  10. Influence of climatic and geographical conditions on the level of energy consumption

    NASA Astrophysics Data System (ADS)

    Klimenko, V. V.

    2012-03-01

    It is shown that the consumption of electricity in modern postindustrial society is highly dependent on fundamental climatic and geographical characteristics, i.e., the average annual air temperature and the effective territory. According to this conception, the world market will be saturated by electric energy at the level of 60 trillion of kWh not earlier than at the end of the current century, which is three times above the present level.

  11. Control of the multimillennial wildfire size in boreal North America by spring climatic conditions

    PubMed Central

    Ali, Adam A.; Blarquez, Olivier; Girardin, Martin P.; Hély, Christelle; Tinquaut, Fabien; El Guellab, Ahmed; Valsecchi, Verushka; Terrier, Aurélie; Bremond, Laurent; Genries, Aurélie; Gauthier, Sylvie; Bergeron, Yves

    2012-01-01

    Wildfire activity in North American boreal forests increased during the last decades of the 20th century, partly owing to ongoing human-caused climatic changes. How these changes affect regional fire regimes (annual area burned, seasonality, and number, size, and severity of fires) remains uncertain as data available to explore fire–climate–vegetation interactions have limited temporal depth. Here we present a Holocene reconstruction of fire regime, combining lacustrine charcoal analyses with past drought and fire-season length simulations to elucidate the mechanisms linking long-term fire regime and climatic changes. We decomposed fire regime into fire frequency (FF) and biomass burned (BB) and recombined these into a new index to assess fire size (FS) fluctuations. Results indicated that an earlier termination of the fire season, due to decreasing summer radiative insolation and increasing precipitation over the last 7.0 ky, induced a sharp decrease in FF and BB ca. 3.0 kyBP toward the present. In contrast, a progressive increase of FS was recorded, which is most likely related to a gradual increase in temperatures during the spring fire season. Continuing climatic warming could lead to a change in the fire regime toward larger spring wildfires in eastern boreal North America. PMID:23213207

  12. Dust deposition in Antarctica in glacial and interglacial climate conditions: a modelling study

    NASA Astrophysics Data System (ADS)

    Sudarchikova, N.; Mikolajewicz, U.; Timmreck, C.; O'Donnell, D.; Schurgers, G.; Sein, D.; Zhang, K.

    2014-09-01

    The mineral dust cycle responds to climate variations and plays an important role in the climate system by affecting the radiative balance of the atmosphere and modifying biogeochemistry. Polar ice cores provide a unique information about deposition of aeolian dust particles transported over long distance. These cores are a paleoclimate proxy archive of climate variability thousands of years ago. The current study is a first attempt to simulate past interglacial dust cycles with a global aerosol-climate model ECHAM5-HAM. The results are used to explain the dust deposition changes in Antarctica in terms of quantitative contribution of different processes, such as emission, atmospheric transport and precipitation, which will help to interpret paleodata from Antarctic ice cores. The investigated periods include four interglacial time-slices such as the pre-industrial control (CTRL), mid-Holocene (6000 yr BP), last glacial inception (115 000 yr BP) and Eemian (126 000 yr BP). One glacial time interval, which is Last Glacial Maximum (LGM) (21 000 yr BP) was simulated as well as to be a reference test for the model. Results suggest an increase of mineral dust deposition globally, and in Antarctica, in the past interglacial periods relative to the pre-industrial CTRL simulation. Approximately two thirds of the increase in the mid-Holocene and Eemian is attributed to enhanced Southern Hemisphere dust emissions. Slightly strengthened transport efficiency causes the remaining one third of the increase in dust deposition. The moderate change of dust deposition in Antarctica in the last glacial inception period is caused by the slightly stronger poleward atmospheric transport efficiency compared to the pre-industrial. Maximum dust deposition in Antarctica was simulated for the glacial period. LGM dust deposition in Antarctica is substantially increased due to 2.6 times higher Southern Hemisphere dust emissions, two times stronger atmospheric transport towards Antarctica, and

  13. Assessing risks from drought and heat stress in productive grasslands under present and future climatic conditions

    NASA Astrophysics Data System (ADS)

    Calanca, Pierluigi; Mosimann, Eric; Meisser, Marco; Deléglise, Claire

    2014-05-01

    Grasslands cover the majority of the world's agricultural area, provide the feedstock for animal production, contribute to the economy of farms, and deliver a variety of ecological and societal services. Assessing responses of grassland ecosystems to climate change, in particular climate-related risks, is therefore an important step toward identifying adaptation options necessary to secure grassland functioning and productivity. Of particular concern are risks in relation to drought and extreme temperatures, on the one hand because grasslands are very sensitive to water stress, on the other hand also because global warming is expected to increase the occurrence and intensity of these events in many agricultural areas of the world. In this contribution we review findings of ongoing experimental and modelling activities that aim at examining the implications of climate extremes and climate change for grassland vegetation dynamics and herbage productivity. Data collected at the Jura foot in western Switzerland indicate that water scarcity and associated anomalous temperatures slowed plant development in relation to both the summer drought of 2003 as well as the spring drought of 2011, with decline in annual yields of up to 40%. Further effects of drought found from the analysis of recent field trials explicitly designed to study the effects of different water management regimes are changes in the functional composition and nutritive value of grasslands. Similar responses are disclosed by simulations with a process based grassland ecosystem model that was originally developed for the simulation of mixed grass/clover swards. Simulations driven with historical weather records from the Swiss Plateau suggest that drought and extreme temperature could represent one of the main reasons for the observed yield variability in productive systems. Simulations with climate change scenarios further reveal important changes in ecosystem dynamics for the current century. The results

  14. Modelling of mineral dust for interglacial and glacial climate conditions with a focus on Antarctica

    DOE PAGESBeta

    Sudarchikova, Natalia; Mikolajewicz, Uwe; Timmreck, C.; O'Donnell, D.; Schurgers, G.; Sein, Dmitry; Zhang, Kai

    2015-05-19

    The mineral dust cycle responds to climate variations and plays an important role in the climate system by affecting the radiative balance of the atmosphere and modifying biogeochemistry. Polar ice cores provide unique information about deposition of aeolian dust particles transported over long distances. These cores are a palaeoclimate proxy archive of climate variability thousands of years ago. The current study is a first attempt to simulate past interglacial dust cycles with a global aerosol–climate model ECHAM5-HAM. The results are used to explain the dust deposition changes in Antarctica in terms of quantitative contribution of different processes, such as emission,more » atmospheric transport and precipitation, which will help to interpret palaeodata from Antarctic ice cores. The investigated periods include four interglacial time slices: the pre-industrial control (CTRL), mid-Holocene (6000 yr BP; hereafter referred to as \\"6 kyr\\"), last glacial inception (115 000 yr BP; hereafter \\"115 kyr\\") and Eemian (126 000 yr BP; hereafter \\"126 kyr\\"). One glacial time interval, the Last Glacial Maximum (LGM) (21 000 yr BP; hereafter \\"21 kyr\\"), was simulated as well to be a reference test for the model. Results suggest an increase in mineral dust deposition globally, and in Antarctica, in the past interglacial periods relative to the pre-industrial CTRL simulation. Approximately two-thirds of the increase in the mid-Holocene and Eemian is attributed to enhanced Southern Hemisphere dust emissions. Slightly strengthened transport efficiency causes the remaining one-third of the increase in dust deposition. The moderate change in dust deposition in Antarctica in the last glacial inception period is caused by the slightly stronger poleward atmospheric transport efficiency compared to the pre-industrial. Maximum dust deposition in Antarctica was simulated for the glacial period. LGM dust deposition in Antarctica is substantially increased due to 2.6 times

  15. Modelling of mineral dust for interglacial and glacial climate conditions with a focus on Antarctica

    SciTech Connect

    Sudarchikova, Natalia; Mikolajewicz, Uwe; Timmreck, C.; O'Donnell, D.; Schurgers, G.; Sein, Dmitry; Zhang, Kai

    2015-05-19

    The mineral dust cycle responds to climate variations and plays an important role in the climate system by affecting the radiative balance of the atmosphere and modifying biogeochemistry. Polar ice cores provide unique information about deposition of aeolian dust particles transported over long distances. These cores are a palaeoclimate proxy archive of climate variability thousands of years ago. The current study is a first attempt to simulate past interglacial dust cycles with a global aerosol–climate model ECHAM5-HAM. The results are used to explain the dust deposition changes in Antarctica in terms of quantitative contribution of different processes, such as emission, atmospheric transport and precipitation, which will help to interpret palaeodata from Antarctic ice cores. The investigated periods include four interglacial time slices: the pre-industrial control (CTRL), mid-Holocene (6000 yr BP; hereafter referred to as \\"6 kyr\\"), last glacial inception (115 000 yr BP; hereafter \\"115 kyr\\") and Eemian (126 000 yr BP; hereafter \\"126 kyr\\"). One glacial time interval, the Last Glacial Maximum (LGM) (21 000 yr BP; hereafter \\"21 kyr\\"), was simulated as well to be a reference test for the model. Results suggest an increase in mineral dust deposition globally, and in Antarctica, in the past interglacial periods relative to the pre-industrial CTRL simulation. Approximately two-thirds of the increase in the mid-Holocene and Eemian is attributed to enhanced Southern Hemisphere dust emissions. Slightly strengthened transport efficiency causes the remaining one-third of the increase in dust deposition. The moderate change in dust deposition in Antarctica in the last glacial inception period is caused by the slightly stronger poleward atmospheric transport efficiency compared to the pre-industrial. Maximum dust deposition in Antarctica was simulated for the glacial period. LGM dust deposition in Antarctica is substantially increased due to 2.6 times higher

  16. Adverse Socioeconomic Conditions and Oocyst-Related Factors Are Associated with Congenital Toxoplasmosis in a Population-Based Study in Minas Gerais, Brazil

    PubMed Central

    Carellos, Ericka Viana Machado; de Andrade, Gláucia Manzan Queiroz; Vasconcelos-Santos, Daniel Vitor; Januário, José Nélio; Romanelli, Roberta Maia Castro; Abreu, Mery Natali Silva; da Silva, Fabiana Maria; Loures, Ivy Rosa Coelho; de Andrade, Juliana Queiroz; Caiaffa, Waleska Teixeira

    2014-01-01

    Objective Congenital toxoplasmosis is a public health problem in Brazil. This study aimed to determine risk factors associated with congenital toxoplasmosis in Minas Gerais which is the second largest Brazilian State based on number of inhabitants, and its territorial extension is larger than that of France. Methods: Population-based case-control study to assess the association between congenital toxoplasmosis and maternal exposure to infection risk factors. The study included mothers/children participating in the Minas Gerais Newborn Screening Program. The cases consisted of 175 mothers of infected children, and the controls consisted of 278 mothers of children without suspected infection. The associations were assessed through binomial logistic regression with p≤0.05. Results The variables associated with lower probability of toxoplasmosis were: older mother age (OR = 0.89; CI95% = 0.85–0.93), higher level of education (OR = 0.85; CI95% = 0.78–0.92), access to potable water (OR = 0.21; CI95% = 0.08–0.51), and home with flush toilet (OR = 0.18; CI95% = 0.04–078). The variables associated with higher probability of infection were: cats in the neighborhood (OR = 2.27; CI95% = 1.27–4.06), owning or visiting homes with domestic cats (OR = 1.90; CI95% = 1.09–3.31), handling the soil (OR = 2.29; CI95% = 1.32–3.96), and eating fresh meat not previously frozen (OR = 3.97; CI95% = 2.17–7.25). After stratification according region of residence (rural or urban/peri-urban), home with flush toilet and consumption of treated water were protective against the disease only in the rural stratum. Conclusions In Minas Gerais, congenital toxoplasmosis has been associated with poor socioeconomic conditions. Considering maternal exposure to sources of Toxoplasma gondii, the predominating risk factors were those related to the ingestion of oocysts. It is expected that these results will contribute to

  17. Modelling the Impact of Human Actors on Groundwater Resources under Conditions of Climate Change

    NASA Astrophysics Data System (ADS)

    Barthel, R.; Reichenau, T. G.; Krimly, T.; Dabbert, S.; Schneider, K.; Mauser, W.; Hennicker, R.

    2012-12-01

    Water resources, activities of human actors and climate change are related in many different and complex ways because of the existence of and strong interactions between various influencing factors, including those that are natural-environmental and socio-economic. The GLOWA-Danube research cooperation has developed the integrated simulation system DANUBIA to simulate water-related influences of global change in different spatial and temporal contexts. DANUBIA is a modular system comprised of 17 dynamically-coupled, process-based model components and a framework which controls the interaction of these components with respect to space and time. This contribution describes approaches and capabilities of DANUBIA with regard to the simulation of global change effects on human decisions in water related fields with a focus on agriculture and groundwater. In agriculture, market prices and legislation can be equally or even more important than water availability in determining farmers' behavior and thus in determining the agricultural impact on water resources quantity and quality. The DANUBIA simulation framework and the associated DeepActor-framework for simulation of decision-making by human actors are presented together with the model components which are most relevant to the interactions between agriculture and groundwater. The approach for developing combination climate and socio-economic scenarios is explained. Exemplary scenario results are shown for the Upper Danube Catchment in Southern Germany. References Barthel, R., Janisch, S., N. Schwarz, A. Trifkovic, D. Nickel, C. Schulz, W. Mauser (2008): An integrated modelling framework for simulating regional-scale actor responses to global change in the water domain. Environmental Modelling and Software, 23, 1095-1121 (doi:10.1016/j.envsoft.2008.02.004) Barthel, R., Reichenau T., Krimly, T., Dabbert, S., Schneider, K., Mauser, W. (2012) Integrated modeling of climate change impacts on agriculture and groundwater

  18. Sources of skill in near-term climate prediction: generating initial conditions

    NASA Astrophysics Data System (ADS)

    Carrassi, A.; Guemas, V.; Doblas-Reyes, F. J.; Volpi, D.; Asif, M.

    2016-03-01

    This study investigates the role of different areas of the ocean in driving the climate variability. The impact of both global and regional ocean nudging on the climate reconstruction obtained with the climate model EC-Earth v2.3 is studied over the period 1960-2012. Ocean temperature and salinity below the mixed layer are relaxed toward the monthly averages from the ORAS4 ocean reanalysis. Three coupled ocean-atmosphere simulations are considered: (1) global ocean nudging, (2) nudging in the global upper ocean (above 2000 m) and (3) nudging in the mid-latitude ocean and at full ocean depth. The experimental setup allows for identifying local and remote effects of nudging on different geographical areas. The validation is based on the correlation coefficients and the root mean square error skill score and concerns the following variables: ocean heat content, ocean barotropic streamfunction, intensity of the ocean gyres and indexes of convection, sea ice extension, near-surface air and sea surface temperature, and El Niño-Southern Oscillation 3.4 index. The results can be summarized as follows: (1) the positive impact on the reconstruction of the ocean state is found almost everywhere and for most of the analyzed variables, including unconstrained variables and/or regions, (2) deep-ocean nudging shows low impact on sea-surface temperature but a significant impact on the ocean circulation, (3) mid-latitude ocean nudging shows systematically the worst performance pointing at the importance of the poles and tropics in reconstructing the global ocean.

  19. Changes on the coastline of buenaventura bay (colombian pacific) and its relationship with the climatic conditions

    NASA Astrophysics Data System (ADS)

    Coca-Domínguez, Oswaldo; Ricaurte-Villota, Constanza; Andres Ordoñez, Silvio

    2016-04-01

    Some authors point out that the variability of a coastal system is the response of physical factors (climate, waves, currents, wind, etc.) or combination of some of them, for example long-term variations in the relationship between climate and supply of sedimentary material. For Colombian Pacific coast it has been said that the regimen of meso-tidal is one of the agents that contribute to changes in the morphology of the littoral zone. Between 2012-2015 was conducted a research in the mouth of Buenaventura Bay (Colombia Pacific coast), using two stations: Soldado point (southern point of the bay) and Bazan point (the northern point of the bay), for those stations the digital elevation model (DEM) was performed using a DGPS with technology GNSS the recent evolution of the coastline and changes in volume of sand from beaches for two scalar approaches were determined: annual and intra-annual. The use of ArcGIS 3D Analyst in the DEMs allowed to calculate the cubic area between the raised surfaces each month. Changes in the coastline were made using Digital Shoreline Analysis System (DSAS) an ARCGIS extension. We used zonal and meridional components of the wind data near the coast from WindSat, rainfall and sea level anomaly data from the database AVISO (Archiving, Validation and Interpretation of Satellite Oceanographic), and sea level pressure (SLP) from NCEP/NCAR (National Center for Environmental Prediction/ National Center for Atmospheric Research), in collaboration with the National Oceanic and Atmospheric Administration (NOAA). Finally, climatic variables were correlated with the rates of coastal erosion and changes in sand volume of the beaches, because wind and precipitation are some of the factors in sediment transport. The study showed erosion rates with negative values in 2014 and 2015 that represent loss of land, the intra-annual variability in September and October were the highest loss of land, this coincides with the values of the highest tides of the

  20. Problems of snowmelt runoff modelling for a variety of physiographic and climatic conditions

    USGS Publications Warehouse

    Leavesley, G.H.

    1989-01-01

    Problems include: a) definition of the spatial and temporal distribution of model input; b) measurement or estimation of snow accumulation, snowmelt, and runoff process parameters for a range of applications and scales; and c) development of accurate short term and long term snowmelt runoff forecasts. Procedures being investigated to solve these problems include: a) integrating conventional and remote-sensing data to improve estimates of input data; b) developing snowmelt process algorithms which have parameters that are closely related to measurable basin and climatic characteristics; and c) updating model paramters and components using measured data or knowledge of past uncertainty. -from Author

  1. A two-year field measurement of methane and nitrous oxide fluxes from rice paddies under contrasting climate conditions

    NASA Astrophysics Data System (ADS)

    Sun, Huifeng; Zhou, Sheng; Fu, Zishi; Chen, Guifa; Zou, Guoyan; Song, Xiangfu

    2016-06-01

    The effects of three irrigation levels (traditional normal amount of irrigation [NA100%], 70%, and 30% of the normal amount [NA70% and NA30%]) and two rice varieties (Oryza sativa L. Huayou14 and Hanyou8) on CH4 and N2O emissions were investigated over two years under contrasting climate conditions (a ‘warm and dry’ season in 2013 and a normal season in 2014). Hanyou8 was developed as a drought-resistant variety. The mean seasonal air temperature in 2013 was 2.3 °C higher than in 2014, while the amount of precipitation from transplanting to the grain-filling stage in 2013 was only 36% of that in 2014. CH4 emission rose by 93–161%, but rice grain yield fell by 7–13% in 2013, compared to 2014 under the NA100% conditions. Surface standing water depths (SSWD) were higher in Hanyou8 than in Huayou14 due to the lower water demand by Hanyou8. A reduction in the amount of irrigation water applied can effectively reduce the CH4 emissions regardless of the rice variety and climate condition. However, less irrigation during the ‘warm and dry’ season greatly decreased Huayou14 grain yield, but had little impact on Hanyou8. In contrast, N2O emission depended more on fertilization and SSWD than on rice variety.

  2. Satellite-based characterization of climatic conditions before large-scale general flowering events in Peninsular Malaysia.

    PubMed

    Azmy, Muna Maryam; Hashim, Mazlan; Numata, Shinya; Hosaka, Tetsuro; Noor, Nur Supardi Md; Fletcher, Christine

    2016-01-01

    General flowering (GF) is a unique phenomenon wherein, at irregular intervals, taxonomically diverse trees in Southeast Asian dipterocarp forests synchronize their reproduction at the community level. Triggers of GF, including drought and low minimum temperatures a few months previously has been limitedly observed across large regional scales due to lack of meteorological stations. Here, we aim to identify the climatic conditions that trigger large-scale GF in Peninsular Malaysia using satellite sensors, Tropical Rainfall Measuring Mission (TRMM) and Moderate Resolution Imaging Spectroradiometer (MODIS), to evaluate the climatic conditions of focal forests. We observed antecedent drought, low temperature and high photosynthetic radiation conditions before large-scale GF events, suggesting that large-scale GF events could be triggered by these factors. In contrast, we found higher-magnitude GF in forests where lower precipitation preceded large-scale GF events. GF magnitude was also negatively influenced by land surface temperature (LST) for a large-scale GF event. Therefore, we suggest that spatial extent of drought may be related to that of GF forests, and that the spatial pattern of LST may be related to that of GF occurrence. With significant new findings and other results that were consistent with previous research we clarified complicated environmental correlates with the GF phenomenon. PMID:27561887

  3. A two-year field measurement of methane and nitrous oxide fluxes from rice paddies under contrasting climate conditions.

    PubMed

    Sun, Huifeng; Zhou, Sheng; Fu, Zishi; Chen, Guifa; Zou, Guoyan; Song, Xiangfu

    2016-01-01

    The effects of three irrigation levels (traditional normal amount of irrigation [NA100%], 70%, and 30% of the normal amount [NA70% and NA30%]) and two rice varieties (Oryza sativa L. Huayou14 and Hanyou8) on CH4 and N2O emissions were investigated over two years under contrasting climate conditions (a 'warm and dry' season in 2013 and a normal season in 2014). Hanyou8 was developed as a drought-resistant variety. The mean seasonal air temperature in 2013 was 2.3 °C higher than in 2014, while the amount of precipitation from transplanting to the grain-filling stage in 2013 was only 36% of that in 2014. CH4 emission rose by 93-161%, but rice grain yield fell by 7-13% in 2013, compared to 2014 under the NA100% conditions. Surface standing water depths (SSWD) were higher in Hanyou8 than in Huayou14 due to the lower water demand by Hanyou8. A reduction in the amount of irrigation water applied can effectively reduce the CH4 emissions regardless of the rice variety and climate condition. However, less irrigation during the 'warm and dry' season greatly decreased Huayou14 grain yield, but had little impact on Hanyou8. In contrast, N2O emission depended more on fertilization and SSWD than on rice variety. PMID:27321231

  4. A two-year field measurement of methane and nitrous oxide fluxes from rice paddies under contrasting climate conditions

    PubMed Central

    Sun, Huifeng; Zhou, Sheng; Fu, Zishi; Chen, Guifa; Zou, Guoyan; Song, Xiangfu

    2016-01-01

    The effects of three irrigation levels (traditional normal amount of irrigation [NA100%], 70%, and 30% of the normal amount [NA70% and NA30%]) and two rice varieties (Oryza sativa L. Huayou14 and Hanyou8) on CH4 and N2O emissions were investigated over two years under contrasting climate conditions (a ‘warm and dry’ season in 2013 and a normal season in 2014). Hanyou8 was developed as a drought-resistant variety. The mean seasonal air temperature in 2013 was 2.3 °C higher than in 2014, while the amount of precipitation from transplanting to the grain-filling stage in 2013 was only 36% of that in 2014. CH4 emission rose by 93–161%, but rice grain yield fell by 7–13% in 2013, compared to 2014 under the NA100% conditions. Surface standing water depths (SSWD) were higher in Hanyou8 than in Huayou14 due to the lower water demand by Hanyou8. A reduction in the amount of irrigation water applied can effectively reduce the CH4 emissions regardless of the rice variety and climate condition. However, less irrigation during the ‘warm and dry’ season greatly decreased Huayou14 grain yield, but had little impact on Hanyou8. In contrast, N2O emission depended more on fertilization and SSWD than on rice variety. PMID:27321231

  5. Satellite-based characterization of climatic conditions before large-scale general flowering events in Peninsular Malaysia

    PubMed Central

    Azmy, Muna Maryam; Hashim, Mazlan; Numata, Shinya; Hosaka, Tetsuro; Noor, Nur Supardi Md.; Fletcher, Christine

    2016-01-01

    General flowering (GF) is a unique phenomenon wherein, at irregular intervals, taxonomically diverse trees in Southeast Asian dipterocarp forests synchronize their reproduction at the community level. Triggers of GF, including drought and low minimum temperatures a few months previously has been limitedly observed across large regional scales due to lack of meteorological stations. Here, we aim to identify the climatic conditions that trigger large-scale GF in Peninsular Malaysia using satellite sensors, Tropical Rainfall Measuring Mission (TRMM) and Moderate Resolution Imaging Spectroradiometer (MODIS), to evaluate the climatic conditions of focal forests. We observed antecedent drought, low temperature and high photosynthetic radiation conditions before large-scale GF events, suggesting that large-scale GF events could be triggered by these factors. In contrast, we found higher-magnitude GF in forests where lower precipitation preceded large-scale GF events. GF magnitude was also negatively influenced by land surface temperature (LST) for a large-scale GF event. Therefore, we suggest that spatial extent of drought may be related to that of GF forests, and that the spatial pattern of LST may be related to that of GF occurrence. With significant new findings and other results that were consistent with previous research we clarified complicated environmental correlates with the GF phenomenon. PMID:27561887

  6. Reduction of uncertainty for estimating runoff with the NRCS CN model by the adaptation to local climatic conditions

    NASA Astrophysics Data System (ADS)

    Durán-Barroso, Pablo; González, Javier; Valdés, Juan B.

    2016-04-01

    Rainfall-runoff quantification is one of the most important tasks in both engineering and watershed management as it allows to identify, forecast and explain watershed response. For that purpose, the Natural Resources Conservation Service Curve Number method (NRCS CN) is the conceptual lumped model more recognized in the field of rainfall-runoff estimation. Furthermore, there is still an ongoing discussion about the procedure to determine the portion of rainfall retained in the watershed before runoff is generated, called as initial abstractions. This concept is computed as a ratio (λ) of the soil potential maximum retention S of the watershed. Initially, this ratio was assumed to be 0.2, but later it has been proposed to be modified to 0.05. However, the actual procedures to convert NRCS CN model parameters obtained under a different hypothesis about λ do not incorporate any adaptation of climatic conditions of each watershed. By this reason, we propose a new simple method for computing model parameters which is adapted to local conditions taking into account regional patterns of climate conditions. After checking the goodness of this procedure against the actual ones in 34 different watersheds located in Ohio and Texas (United States), we concluded that this novel methodology represents the most accurate and efficient alternative to refit the initial abstraction ratio.

  7. Projected wave conditions in the Eastern North Pacific under the influence of two CMIP5 climate scenarios

    USGS Publications Warehouse

    Erikson, Li H.; Hegermiller, Christie; Barnard, Patrick; Ruggiero, Peter; van Ormondt, Martin

    2015-01-01

    Hindcast and 21st century winds, simulated by General Circulation Models (GCMs), were used to drive global- and regional-scale spectral wind-wave generation models in the Pacific Ocean Basin to assess future wave conditions along the margins of the North American west coast and Hawaiian Islands. Three-hourly winds simulated by four separate GCMs were used to generate an ensemble of wave conditions for a recent historical time-period (1976–2005) and projections for the mid and latter parts of the 21st century under two radiative forcing scenarios (RCP 4.5 and RCP 8.5), as defined by the fifth phase of the Coupled Model Inter-comparison Project (CMIP5) experiments. Comparisons of results from historical simulations with wave buoy and ERA-Interim wave reanalysis data indicate acceptable model performance of wave heights, periods, and directions, giving credence to generating projections. Mean and extreme wave heights are projected to decrease along much of the North American west coast. Extreme wave heights are projected to decrease south of ∼50°N and increase to the north, whereas extreme wave periods are projected to mostly increase. Incident wave directions associated with extreme wave heights are projected to rotate clockwise at the eastern end of the Aleutian Islands and counterclockwise offshore of Southern California. Local spatial patterns of the changing wave climate are similar under the RCP 4.5 and RCP 8.5 scenarios, but stronger magnitudes of change are projected under RCP 8.5. Findings of this study are similar to previous work using CMIP3 GCMs that indicates decreasing mean and extreme wave conditions in the Eastern North Pacific, but differ from other studies with respect to magnitude and local patterns of change. This study contributes toward a larger ensemble of global and regional climate projections needed to better assess uncertainty of potential future wave climate change, and provides model boundary conditions for assessing the impacts of

  8. Projected wave conditions in the Eastern North Pacific under the influence of two CMIP5 climate scenarios

    NASA Astrophysics Data System (ADS)

    Erikson, L. H.; Hegermiller, C. A.; Barnard, P. L.; Ruggiero, P.; van Ormondt, M.

    2015-12-01

    Hindcast and 21st century winds, simulated by General Circulation Models (GCMs), were used to drive global- and regional-scale spectral wind-wave generation models in the Pacific Ocean Basin to assess future wave conditions along the margins of the North American west coast and Hawaiian Islands. Three-hourly winds simulated by four separate GCMs were used to generate an ensemble of wave conditions for a recent historical time-period (1976-2005) and projections for the mid and latter parts of the 21st century under two radiative forcing scenarios (RCP 4.5 and RCP 8.5), as defined by the fifth phase of the Coupled Model Inter-comparison Project (CMIP5) experiments. Comparisons of results from historical simulations with wave buoy and ERA-Interim wave reanalysis data indicate acceptable model performance of wave heights, periods, and directions, giving credence to generating projections. Mean and extreme wave heights are projected to decrease along much of the North American west coast. Extreme wave heights are projected to decrease south of ∼50°N and increase to the north, whereas extreme wave periods are projected to mostly increase. Incident wave directions associated with extreme wave heights are projected to rotate clockwise at the eastern end of the Aleutian Islands and counterclockwise offshore of Southern California. Local spatial patterns of the changing wave climate are similar under the RCP 4.5 and RCP 8.5 scenarios, but stronger magnitudes of change are projected under RCP 8.5. Findings of this study are similar to previous work using CMIP3 GCMs that indicates decreasing mean and extreme wave conditions in the Eastern North Pacific, but differ from other studies with respect to magnitude and local patterns of change. This study contributes toward a larger ensemble of global and regional climate projections needed to better assess uncertainty of potential future wave climate change, and provides model boundary conditions for assessing the impacts of

  9. A Preliminary Evaluation of Season-ahead Flood Prediction Conditioned on Large-scale Climate Drivers

    NASA Astrophysics Data System (ADS)

    Lee, Donghoon; Ward, Philip; Block, Paul

    2016-04-01

    Globally, flood disasters lead all natural hazards in terms of impacts on society, causing billions of dollars of damages each year. Typically, short-term forecasts emphasize immediate emergency actions, longer-range forecasts, on the order of months to seasons, however, can compliment short-term forecasts by focusing on disaster preparedness. In this study, the inter-annual variability of large-scale climate drivers (e.g. ENSO) is investigated to understand the prospects for skillful season-ahead flood prediction globally using PCR-GLOBWB modeled simulations. For example, global gridded correlations between discharge and Nino 3.4 are calculated, with notably strong correlations in the northwestern (-0.4~-0.6) and the southeastern (0.4~0.6) United States, and the Amazon river basin (-0.6~-0.8). Coupled interactions from multiple, simultaneous climate drivers are also evaluated. Skillful prediction has the potential to estimate season-ahead flood probabilities, flood extent, damages, and eventually integrate into early warning systems. This global approach is especially attractive for areas with limited observations and/or little capacity to develop early warning flood systems.

  10. Wildfire Impacts Upon US Air Quality for Current and Future Climate Conditions

    NASA Astrophysics Data System (ADS)

    Gonzalez Abraham, R.; Chung, S. H.; Lamb, B. K.; Tao, I.; Avise, J. C.; Stavros, E. N.; Strand, T. T.; McKenzie, D.; Guenther, A. B.; Wiedinmyer, C.; Duhl, T.; Salathe, E. P.; Zhang, Y.

    2011-12-01

    Wildfires can have an important impact on regional air quality as they are large and intermittent sources of primary particulates, secondary aerosols, and ozone precursors. As part of an ongoing analysis on the effects of global change upon US air quality, we report results for current and future decade simulations of the inter-relationship among climate change, wildfires and air quality. The results are reported for the Northwest, Southwest, and Central Rockies regions of the US. Meteorological fields from the ECHAM5 global climate model for the IPCC A1B scenario were downscaled using the Weather Research Forecast (WRF) model to drive the MEGAN biogenic emissions model, a stochastic fire occurrence model, Fire Simulation Builder (FSB), and the CMAQ chemical transport model to predict ozone and aerosol concentrations. Simulations were completed for two nested domains covering most of the northern hemisphere from eastern Asia to North America at 220 km horizontal resolution (hemispheric domain) and covering the continental US at 36 km resolution (CONUS). Sensitivity studies were conducted for representative summer periods with fire occurrence generated from FSB within the current (1995-2004) and future decade (2045-2054) and using current decade historical fire data obtained from the Bureau of Land Management Database. Results are reported in terms of the effects of global change upon fire occurrence, fire plume transport and PM and ozone pollutant levels.

  11. Estimating permafrost distribution in the maritime Southern Alps, New Zealand, based on climatic conditions at rock glacier sites

    NASA Astrophysics Data System (ADS)

    Sattler, Katrin; Anderson, Brian; Mackintosh, Andrew; Norton, Kevin; de Róiste, Mairéad

    2016-02-01

    Alpine permafrost occurrence in maritime climates has received little attention, despite suggestions that permafrost may occur at lower elevations than in continental climates. To assess the spatial and altitudinal limits of permafrost in the maritime Southern Alps, we developed and tested a catchment-scale distributed permafrost estimate. We used logistic regression to identify the relationship between permafrost presence at 280 active and relict rock glacier sites and the independent variables a) mean annual air temperature and b) potential incoming solar radiation in snow free months. The statistical relationships were subsequently employed to calculate the spatially-distributed probability of permafrost occurrence, using a probability of ≥ 0.6 to delineate the potential permafrost extent. Our results suggest that topoclimatic conditions are favorable for permafrost occurrence in debris-mantled slopes above ~ 2000 m in the central Southern Alps and above ~ 2150 m in the more northern Kaikoura ranges. Considering the well-recognized latitudinal influence on global permafrost occurrences, these altitudinal limits are lower than the limits observed in other mountain regions. We argue that the Southern Alps' lower distribution limits may exemplify an oceanic influence on global permafrost distribution. Reduced ice-loss due to moderate maritime summer temperature extremes may facilitate the existence of permafrost at lower altitudes than in continental regions at similar latitude. Empirical permafrost distribution models derived in continental climates may consequently be of limited applicability in maritime settings.

  12. H. pylori CagL-Y58/E59 Prime Higher Integrin α5β1 in Adverse pH Condition to Enhance Hypochlorhydria Vicious Cycle for Gastric Carcinogenesis

    PubMed Central

    Yang, Hsiao-Bai; Chang, Wei-Lun; Sheu, Bor-Shyang

    2013-01-01

    Background/Aims H. pylori CagL amino acid polymorphisms such as Y58/E59 can increase integrin α5β1 expression and gastric cancer risk. Hypochlorhydria during chronic H. pylori infection promotes gastric carcinogenesis. The study test whether CagL-Y58/E59 isolates may regulate integrin α5β1 to translocate CagA via the type IV secretory system even under adverse pH conditions, and whether the integrin α5β1 expression primed by H. pylori is a pH-dependent process involving hypochlorhydria in a vicious cycle to promote gastric carcinogenesis. Methods The expressions of integrin α5 and β1, CagA phosphorylation, IL-8, FAK, EGFR, and AKT activation of AGS cells exposed to CagL-Y58/E59 H. pylori, isogenic mutants, and different H. pylori CagL amino acid replacement mutants under different pH values were determined. Differences in the pepsinogen I/II ratio (indirectly indicating gastric acidity) and gastric integrin α5β1 expression were compared among the 172 H. pylori-infected patients with different cancer risks. Results Even under adversely low pH condition, H. pylori CagL-Y58/E59 still keep active integrin β1 with stronger binding affinity, CagA translocation, IL-8, FAK, EGFR, and AKT activation than the other mutants (p<0.05). The in vitro assay revealed higher priming of integrin α5β1 by H. pylori under elevated pH as hypochlorhydria (p<0.05). In the H. pylori-infected patients, the gastric integrin α5β1 expressions were higher in those with pepsinogen I/II ratio <6 than in those without (p<0.05). Conclusions H. pylori CagL-Y58/E59 prime higher integrin under adverse pH and may involve to enhance hypochlorhydria vicious cycle for gastric carcinogenesis, and thus require an early eradication. PMID:24009701

  13. Modeling Nitrogen Losses in Conventional and Advanced Soil-Based Onsite Wastewater Treatment Systems under Current and Changing Climate Conditions

    PubMed Central

    Cooper, Jennifer

    2016-01-01

    Most of the non-point source nitrogen (N) load in rural areas is attributed to onsite wastewater treatment systems (OWTS). Nitrogen compounds cause eutrophication, depleting the oxygen in marine ecosystems. OWTS rely on physical, chemical and biological soil processes to treat wastewater and these processes may be affected by climate change. We simulated the fate and transport of N in different types of OWTS drainfields, or soil treatment areas (STA) under current and changing climate scenarios, using 2D/3D HYDRUS software. Experimental data from a mesocosm-scale study, including soil moisture content, and total N, ammonium (NH4+) and nitrate (NO3-) concentrations, were used to calibrate the model. A water content-dependent function was used to compute the nitrification and denitrification rates. Three types of drainfields were simulated: (1) a pipe-and-stone (P&S), (2) advanced soil drainfields, pressurized shallow narrow drainfield (PSND) and (3) Geomat (GEO), a variation of SND. The model was calibrated with acceptable goodness-of-fit between the observed and measured values. Average root mean square error (RSME) ranged from 0.18 and 2.88 mg L-1 for NH4+ and 4.45 mg L-1 to 9.65 mg L-1 for NO3- in all drainfield types. The calibrated model was used to estimate N fluxes for both conventional and advanced STAs under current and changing climate conditions, i.e. increased soil temperature and higher water table. The model computed N losses from nitrification and denitrification differed little from measured losses in all STAs. The modeled N losses occurred mostly as NO3- in water outputs, accounting for more than 82% of N inputs in all drainfields. Losses as N2 were estimated to be 10.4% and 9.7% of total N input concentration for SND and Geo, respectively. The highest N2 losses, 17.6%, were estimated for P&S. Losses as N2 increased to 22%, 37% and 21% under changing climate conditions for Geo, PSND and P&S, respectively. These findings can provide practitioners

  14. A Simulation/Optimization approach to manage groundwater resources in the Gaza aquifer (Palestinian Territories) under climate change conditions

    NASA Astrophysics Data System (ADS)

    Dentoni, Marta; Qahman, Khalid; Deidda, Roberto; Paniconi, Claudio; Lecca, Giuditta

    2013-04-01

    The Gaza aquifer is the main source of water for agricultural, domestic, and industrial uses in the Gaza Strip. The rapid increase on water demand due to continuous population growth has led to water scarcity and contamination by seawater intrusion (SWI). Furthermore, current projections of future climatic conditions (IPCC, 2007) point to potential decreases in available water, both inflows and outflows. A numerical assessment of SWI in the Gaza coastal aquifer under climate induced changes has been carried out by means of the CODESA-3D model of density-dependent variably saturated flow and salt transport in groundwaters. After integrating available data on climatology, geology, geomorphology, hydrology, hydrogeology, soil use, and groundwater exploitation relative to the period 1935-2010, the calibrated and validated model was used to simulate the response of the hydrological basin to actual and future scenarios of climate change obtained from different regional circulation models. The results clearly show that, if current pumping rates are maintained, seawater intrusion will worsen. To manage sustainable aquifer development under effective recharge operations and water quality constraints, a decision support system based on a simulation/optimization (S/O) approach was applied to the Gaza study site. The S/O approach is based on coupling the CODESA-3D model with the Carroll's Genetic Algorithm Driver. The optimization model incorporates two conflicting objectives using a penalty method: maximizing pumping rates from the aquifer wells while limiting the salinity of the water withdrawn. The resulting coastal aquifer management model was applied over a 30-year time period to identify the optimum spatial distribution of pumping rates at the control wells. The optimized solution provides for a general increase in water table levels and a decrease in the total extracted salt mass while keeping total abstraction rates relatively constant, with reference to non

  15. Modeling Nitrogen Losses in Conventional and Advanced Soil-Based Onsite Wastewater Treatment Systems under Current and Changing Climate Conditions.

    PubMed

    Morales, Ivan; Cooper, Jennifer; Amador, José A; Boving, Thomas B

    2016-01-01

    Most of the non-point source nitrogen (N) load in rural areas is attributed to onsite wastewater treatment systems (OWTS). Nitrogen compounds cause eutrophication, depleting the oxygen in marine ecosystems. OWTS rely on physical, chemical and biological soil processes to treat wastewater and these processes may be affected by climate change. We simulated the fate and transport of N in different types of OWTS drainfields, or soil treatment areas (STA) under current and changing climate scenarios, using 2D/3D HYDRUS software. Experimental data from a mesocosm-scale study, including soil moisture content, and total N, ammonium (NH4+) and nitrate (NO3-) concentrations, were used to calibrate the model. A water content-dependent function was used to compute the nitrification and denitrification rates. Three types of drainfields were simulated: (1) a pipe-and-stone (P&S), (2) advanced soil drainfields, pressurized shallow narrow drainfield (PSND) and (3) Geomat (GEO), a variation of SND. The model was calibrated with acceptable goodness-of-fit between the observed and measured values. Average root mean square error (RSME) ranged from 0.18 and 2.88 mg L-1 for NH4+ and 4.45 mg L-1 to 9.65 mg L-1 for NO3- in all drainfield types. The calibrated model was used to estimate N fluxes for both conventional and advanced STAs under current and changing climate conditions, i.e. increased soil temperature and higher water table. The model computed N losses from nitrification and denitrification differed little from measured losses in all STAs. The modeled N losses occurred mostly as NO3- in water outputs, accounting for more than 82% of N inputs in all drainfields. Losses as N2 were estimated to be 10.4% and 9.7% of total N input concentration for SND and Geo, respectively. The highest N2 losses, 17.6%, were estimated for P&S. Losses as N2 increased to 22%, 37% and 21% under changing climate conditions for Geo, PSND and P&S, respectively. These findings can provide practitioners

  16. Water Management Decisions using Multiple Hydrologic Models Within the San Juan River Basin Under Changing Climate Conditions

    NASA Astrophysics Data System (ADS)

    Piechota, T. C.; Miller, W. P.; Butler, R. A.; Prairie, J. R.; Derosa, G. M.

    2011-12-01

    A modified version of the Bureau of Reclamation (Reclamation) long-term planning model, Colorado River Simulation System (CRSS), is used to evaluate whether hydrologic model choice has an impact on critical decision variables within the San Juan River Basin when evaluating potential impacts of climate change through 2099. The distributed Variable Infiltration Capacity (VIC) model and the lumped National Weather Service (NWS) River Forecast System (RFS) were each used to project future streamflow; these projections of streamflow were then used to force Reclamation's CRSS model over the San Juan River Basin. Both hydrologic models were compared to evaluate whether or not uncertainty in climatic input generated from General Circulation Models outweighed differences between the hydrologic models. Differences in methodologies employed by each hydrologic model had a significant impact on projected streamflow within the basin. Both models project decreased water availability under changing climate conditions within the San Juan River Basin, but disagree on the magnitude of the decrease. On average, total naturalized inflow within the San Juan River Basin into the Navajo Reservoir is approximately 15% higher using inflows derived using the VIC model than those inflows developed using the RFS model; average projected tributary inflow from the San Juan River Basin to the Colorado River is approximately 25% higher using inflows derived using the VIC model than those inflows developed using the RFS. Overall, there is a higher risk and magnitude of shortage within the San Juan River Basin using streamflow developed using the RFS model as compared to inflow scenarios developed using the VIC model. Model choice was found to have a significant impact on the evaluation of climate change impacts over the San Juan River Basin.

  17. Comparison of 3 coupled models in the North Sea region under todays and future climate conditions

    NASA Astrophysics Data System (ADS)

    Klein, Birgit; Bülow, Katharina; Dieterich, Christian; Heinrich, Hartmut; Hüttl-Kabus, Sabine; Mayer, Bernhard; Meier, Markus; Mikolajewicz, Uwe; Narayan, Nikesh; Pohlmann, Thomas; Rosenhagen, Gudrun; Sein, Dmitry; Su, Jian

    2014-05-01

    Most of the common global climate models (coupled ocean/atmosphere ocean models) have too large spatial scales to be suitable in the North Sea area. Therefore either high-resolution global models have to be run or dynamical downscaling of the model-output has to be employed using regional models. Regionalized climate change simulations for the North and Baltic Sea are carried out with coupled ocean atmosphere models in the framework of the research program KLIWAS. The numerical simulations are performed by the Max-Planck Institute for Meteorology (MPI), the Swedish Meteorological and Hydrological Institute (SMHI) and the Institute of Oceanography (IfM Hamburg). Output from the models is analyzed jointly with the Federal Maritime service (BSH) and the German weather service (DWD/SWA). Temperature and sea level evolution in all three models is much more similar than the predicted salinity changes. The spatial patterns of the salinity fields in the North Sea are the result of a complex balance of fresh water input from the rivers, discharge of low salinity waters from the Baltic, inflow of high salinity waters from the Atlantic and input from the atmosphere. The hindcast simulations for this parameter are similar at the basin scale in all three models but are showing different patterns at smaller scales. All models are predicting a salinity decrease towards the end of the 21 century (2070-2099) to (1970-1999), independent of these differences, but it is much more pronounced in the runs of MPIOM/REMO and NEMO/RCA compared to HAMSOM/REMO. All models agree on the fact of a major freshening of the Baltic Outflow, while the magnitude of the freshening and the affected area in the North Sea are represented differently. The models are showing a temperature increase in the order of 2 °C at the end of the 21 century. The areas affected by Atlantic inflow are showing smaller temperature increases due to the lesser warming in the Atlantic. The annual cycle is slightly perturbed

  18. Evaluating climate field reconstruction techniques using improved emulations of real-world conditions

    NASA Astrophysics Data System (ADS)

    Wang, J.; Emile-Geay, J.; Guillot, D.; Smerdon, J. E.; Rajaratnam, B.

    2013-06-01

    Pseudoproxy experiments (PPEs) have become an essential framework for evaluating paleoclimate reconstruction methods. Most existing PPE studies assume constant proxy availability through time and uniform proxy quality across the pseudoproxy network. Real multi-proxy networks are, however, marked by pronounced disparities in proxy quality, and a steep decline in proxy availability back in time, either of which may have large effects on reconstruction skill. Additionally, an investigation of a real-world global multi-proxy network suggests that proxies are not exclusively indicators of local climate; rather, many are indicative of large-scale teleconnections. A suite of PPEs constructed from a millennium-length general circulation model simulation is thus designed to mimic these various real-world characteristics. The new pseudoproxy network is used to evaluate four climate field reconstruction (CFR) techniques: truncated total least square embedded within the regularized EM algorithm (RegEM-TTLS), the Mann et al. (2009) implementation of RegEM-TTLS (M09), canonical correlation analysis (CCA), and Gaussian graphical models embedded within RegEM (GraphEM). Each method's risk properties are also assessed via a 100-member noise ensemble. Contrary to expectation, it is found that reconstruction skill does not vary monotonically with proxy availability, but rather is a function of the type of climate variability (forced events vs. internal variability). The use of realistic spatiotemporal pseudoproxy characteristics also exposes large inter-method differences. Despite the comparable fidelity in reconstructing the global mean temperature, spatial skill varies considerably between CFR techniques. Both GraphEM and CCA efficiently exploit teleconnections, and produce consistent reconstructions across the ensemble. RegEM-TTLS and M09 appear advantageous for reconstructions on highly noisy data, but are subject to larger stochastic variations across different realizations of

  19. Validation of a regional climate model over Dome C, Antarctica, for summer conditions

    NASA Astrophysics Data System (ADS)

    Gallée, Hubert; Vignon, Étienne; Genthon, Christophe; Argentini, Stefania

    2016-04-01

    Regional climate model MAR (Modèle Atmosphérique Régional) was run for the region of Dome C located on the East Antarctic plateau, during summer. A very high vertical resolution is set up in the lower troposphere. Model output is compared with temperatures and winds observed near the surface and from a 45 m high tower as well as sodar and radiation data. MAR is generally in very good agreement with the observations during clear sky days, but sometimes underestimates cloud formation, leading to an underestimation of the simulated downward long-wave radiation. Absorbed short-wave radiation may also be slightly overestimated due to an underestimation of the snow albedo, and this influences the surface energy budget and atmospheric turbulence.

  20. Creep in Wood Under Variable Climate Conditions: Numerical Modeling and Experimental Validation

    NASA Astrophysics Data System (ADS)

    Dubois, F.; Randriambololona, H.; Petit, C.

    2005-09-01

    This paper deals with the modeling of linear viscoelastic behavior and strain accumulation (accelerated creep) during moisture content changes in timber. A generalized Kelvin-Voigt model is used and associated in series with a shrinkage-swelling element depending on the mechanical and moisture content states of materials. The hygrothermal aging due to climatic variations implies an evolution of rheological parameters depending upon moisture content and temperature. Two distinct viscoelastic laws, one for drying and the other for moistening, are coupled according to the thermodynamic principles when wood is subjected to nonmonotonous moisture variations. An incremental formulation of behavior is established in the finite element program CAST3M (Software developed by C.E.A. (Commissariat á l'Energi Atomique) and an experimental validation from tension creep-recovery tests is presented.

  1. The occurrence of melioidosis is related to different climatic conditions in distinct topographical areas of Taiwan.

    PubMed

    Mu, J-J; Cheng, P-Y; Chen, Y-S; Chen, P-S; Chen, Y-L

    2014-02-01

    This study assessed the correlations between the incidence of melioidosis and rainfall, wind strength and wind direction in both the flat and hilly regions of Taiwan. Data from the melioidosis and climate databases from 2005 to 2011 were combined and analysed. With the inclusion of a lag time accounting for a possible incubation period for melioidosis, the daily rainfall and wind-speed data were correlated with the number of confirmed melioidosis cases. The incidence of melioidosis in the flat region was related to the wind speed (>19 m/s) and the specific angle (150°, 220°, 280°) of the wind direction. Rainfall is a common environmental factor that contributes to an increase in the incidence of melioidosis in both areas; however, the contribution of wind strength or wind direction to the spread of melioidosis was restricted to areas with specific topographical characteristics, such as hills. PMID:23714119

  2. Evaluating climate field reconstruction techniques using improved emulations of real-world conditions

    NASA Astrophysics Data System (ADS)

    Wang, J.; Emile-Geay, J.; Guillot, D.; Smerdon, J. E.; Rajaratnam, B.

    2014-01-01

    Pseudoproxy experiments (PPEs) have become an important framework for evaluating paleoclimate reconstruction methods. Most existing PPE studies assume constant proxy availability through time and uniform proxy quality across the pseudoproxy network. Real multiproxy networks are, however, marked by pronounced disparities in proxy quality, and a steep decline in proxy availability back in time, either of which may have large effects on reconstruction skill. A suite of PPEs constructed from a millennium-length general circulation model (GCM) simulation is thus designed to mimic these various real-world characteristics. The new pseudoproxy network is used to evaluate four climate field reconstruction (CFR) techniques: truncated total least squares embedded within the regularized EM (expectation-maximization) algorithm (RegEM-TTLS), the Mann et al. (2009) implementation of RegEM-TTLS (M09), canonical correlation analysis (CCA), and Gaussian graphical models embedded within RegEM (GraphEM). Each method's risk properties are also assessed via a 100-member noise ensemble. Contrary to expectation, it is found that reconstruction skill does not vary monotonically with proxy availability, but also is a function of the type and amplitude of climate variability (forced events vs. internal variability). The use of realistic spatiotemporal pseudoproxy characteristics also exposes large inter-method differences. Despite the comparable fidelity in reconstructing the global mean temperature, spatial skill varies considerably between CFR techniques. Both GraphEM and CCA efficiently exploit teleconnections, and produce consistent reconstructions across the ensemble. RegEM-TTLS and M09 appear advantageous for reconstructions on highly noisy data, but are subject to larger stochastic variations across different realizations of pseudoproxy noise. Results collectively highlight the importance of designing realistic pseudoproxy networks and implementing multiple noise realizations of PPEs

  3. Hindcasting Historical Breeding Conditions for an Endangered Salamander in Ephemeral Wetlands of the Southeastern USA: Implications of Climate Change.

    PubMed

    Chandler, Houston C; Rypel, Andrew L; Jiao, Yan; Haas, Carola A; Gorman, Thomas A

    2016-01-01

    The hydroperiod of ephemeral wetlands is often the most important characteristic determining amphibian breeding success, especially for species with long development times. In mesic and wet pine flatwoods of the southeastern United States, ephemeral wetlands were a common landscape feature. Reticulated flatwoods salamanders (Ambystoma bishopi), a federally endangered species, depend exclusively on ephemeral wetlands and require at least 11 weeks to successfully metamorphose into terrestrial adults. We empirically modeled hydroperiod of 17 A. bishopi breeding wetlands by combining downscaled historical climate-model data with a recent 9-year record (2006-2014) of observed water levels. Empirical models were subsequently used to reconstruct wetland hydrologic conditions from 1896-2014 using the downscaled historical climate datasets. Reconstructed hydroperiods for the 17 wetlands were highly variable through time but were frequently unfavorable for A. bishopi reproduction (e.g., only 61% of years, using a conservative estimate of development time [12 weeks], were conducive to larval development and metamorphosis). Using change-point analysis, we identified significant shifts in average hydroperiod over the last century in all 17 wetlands. Mean hydroperiods were shorter in recent years than at any other point since 1896, and thus less suitable for A. bishopi reproduction. We suggest that climate change will continue to impact the reproductive success of flatwoods salamanders and other ephemeral wetland breeders by reducing the number of years these wetlands have suitable hydroperiods. Consequently, we emphasize the importance of conservation and management for mitigating other forms of habitat degradation, especially maintenance of high quality breeding sites where reproduction can occur during appropriate environmental conditions. PMID:26910245

  4. Hindcasting Historical Breeding Conditions for an Endangered Salamander in Ephemeral Wetlands of the Southeastern USA: Implications of Climate Change

    PubMed Central

    Chandler, Houston C.; Rypel, Andrew L.; Jiao, Yan; Haas, Carola A.; Gorman, Thomas A.

    2016-01-01

    The hydroperiod of ephemeral wetlands is often the most important characteristic determining amphibian breeding success, especially for species with long development times. In mesic and wet pine flatwoods of the southeastern United States, ephemeral wetlands were a common landscape feature. Reticulated flatwoods salamanders (Ambystoma bishopi), a federally endangered species, depend exclusively on ephemeral wetlands and require at least 11 weeks to successfully metamorphose into terrestrial adults. We empirically modeled hydroperiod of 17 A. bishopi breeding wetlands by combining downscaled historical climate-model data with a recent 9-year record (2006–2014) of observed water levels. Empirical models were subsequently used to reconstruct wetland hydrologic conditions from 1896–2014 using the downscaled historical climate datasets. Reconstructed hydroperiods for the 17 wetlands were highly variable through time but were frequently unfavorable for A. bishopi reproduction (e.g., only 61% of years, using a conservative estimate of development time [12 weeks], were conducive to larval development and metamorphosis). Using change-point analysis, we identified significant shifts in average hydroperiod over the last century in all 17 wetlands. Mean hydroperiods were shorter in recent years than at any other point since 1896, and thus less suitable for A. bishopi reproduction. We suggest that climate change will continue to impact the reproductive success of flatwoods salamanders and other ephemeral wetland breeders by reducing the number of years these wetlands have suitable hydroperiods. Consequently, we emphasize the importance of conservation and management for mitigating other forms of habitat degradation, especially maintenance of high quality breeding sites where reproduction can occur during appropriate environmental conditions. PMID:26910245

  5. Influence of climatic variables, forest type, and condition on activity patterns of Geoffroyi's spider monkeys throughout Mesoamerica.

    PubMed

    González-Zamora, Arturo; Arroyo-Rodríguez, Víctor; Chaves, Oscar M; Sánchez-López, Sónia; Aureli, Filippo; Stoner, Kathryn E

    2011-12-01

    Understanding how species cope with variations in climatic conditions, forest types and habitat amount is a fundamental challenge for ecologists and conservation biologists. We used data from 18 communities of Mesoamerican spider monkeys (Ateles geoffroyi) throughout their range to determine whether their activity patterns are affected by climatic variables (temperature and rainfall), forest types (seasonal and nonseasonal forests), and forest condition (continuous and fragmented). Data were derived from 15 published and unpublished studies carried out in four countries (Mexico, El Salvador, Costa Rica, and Panama), cumulatively representing more than 18 years (221 months, >3,645 hr) of behavioral observations. Overall, A. geoffroyi spent most of their time feeding (38.4 ± 14.0%, mean ± SD) and resting (36.6 ± 12.8%) and less time traveling (19.8 ± 11.3%). Resting and feeding were mainly affected by rainfall: resting time increased with decreasing rainfall, whereas feeding time increased with rainfall. Traveling time was negatively related to both rainfall and maximum temperature. In addition, both resting and traveling time were higher in seasonal forests (tropical dry forest and tropical moist forest) than in nonseasonal forests (tropical wet forest), but feeding time followed the opposite pattern. Furthermore, spider monkeys spent more time feeding and less time resting (i.e., higher feeding effort) in forest fragments than in continuous forest. These findings suggest that global climate changes and habitat deforestation and fragmentation in Mesoamerica will threaten the survival of spider monkeys and reduce the distributional range of the species in the coming decades. PMID:21898512

  6. Thermal comfort in air-conditioned buildings in hot and humid climates--why are we not getting it right?

    PubMed

    Sekhar, S C

    2016-02-01

    While there are plenty of anecdotal experiences of overcooled buildings in summer, evidence from field studies suggests that there is indeed an issue of overcooling in tropical buildings. The findings suggest that overcooled buildings are not a consequence of occupant preference but more like an outcome of the HVAC system design and operation. Occupants' adaptation in overcooled indoor environments through additional clothing cannot be regarded as an effective mitigating strategy for cold thermal discomfort. In the last two decades or so, several field studies and field environmental chamber studies in the tropics provided evidence for occupants' preference for a warmer temperature with adaptation methods such as elevated air speeds. It is important to bear in mind that indoor humidity levels are not compromised as they could have an impact on the inhaled air condition that could eventually affect perceived air quality. This review article has attempted to track significant developments in our understanding of the thermal comfort issues in air-conditioned office and educational buildings in hot and humid climates in the last 25 years, primarily on occupant preference for thermal comfort in such climates. The issue of overcooled buildings, by design intent or otherwise, is discussed in some detail. Finally, the article has explored some viable adaptive thermal comfort options that show considerable promise for not only improving thermal comfort in tropical buildings but are also energy efficient and could be seen as sustainable solutions. PMID:25626476

  7. Bacteria Transport in a Soil-Based Wastewater Treatment System under Simulated Operational and Climate Change Conditions.

    PubMed

    Morales, Ivan; Amador, José A; Boving, Thomas

    2015-09-01

    Bacteria removal efficiencies in a conventional soil-based wastewater treatment system (OWTS) have been modeled to elucidate the fate and transport of bacteria under environmental and operational conditions that might be expected under changing climatic conditions. The HYDRUS 2D/3D software was used to model the impact of changing precipitation patterns, bacteria concentrations, hydraulic loading rates (HLRs), and higher subsurface temperatures at different depths and soil textures. Modeled effects of bacteria concentration shows that greater depth of treatment was required in coarser soils than in fine-textured ones to remove . The initial removal percentage was higher when HLR was lower, but it was greater when HLR was higher. When a biomat layer was included in the transport model, the performance of the system improved by up to 12.0%. Lower bacteria removal (<5%) was observed at all depths under the influence of precipitation rates ranging from 5 to 35 cm, and 35-cm rainfall combined with a 70% increase in HLR. Increased subsurface temperature (23°C) increased bacteria removal relative to a lower temperature range (5-20°C). Our results show that the model is able to effectively simulate bacteria removal and the effect of precipitation and temperature in different soil textures. It appears that the performance of OWTS may be impacted by changing climate. PMID:26436263

  8. Climate change, phenology, and habitat degradation: drivers of gosling body condition and juvenile survival in lesser snow geese.

    PubMed

    Aubry, Lise M; Rockwell, Robert F; Cooch, Evan G; Brook, Rodney W; Mulder, Christa P H; Koons, David N

    2013-01-01

    Nesting migratory geese are among the dominant herbivores in (sub) arctic environments, which have undergone unprecedented increases in temperatures and plant growing days over the last three decades. Within these regions, the Hudson Bay Lowlands are home to an overabundant breeding population of lesser snow geese that has dramatically damaged the ecosystem, with cascading effects at multiple trophic levels. In some areas the overabundance of geese has led to a drastic reduction in available forage. In addition, warming of this region has widened the gap between goose migration timing and plant green-up, and this 'mismatch' between goose and plant phenologies could in turn affect gosling development. The dual effects of climate change and habitat quality on gosling body condition and juvenile survival are not known, but are critical for predicting population growth and related degradation of (sub) arctic ecosystems. To address these issues, we used information on female goslings marked and measured between 1978 and 2005 (4125 individuals). Goslings that developed within and near the traditional center of the breeding colony experienced the effects of long-term habitat degradation: body condition and juvenile survival declined over time. In newly colonized areas, however, we observed the opposite pattern (increase in body condition and juvenile survival). In addition, warmer than average winters and summers resulted in lower gosling body condition and first-year survival. Too few plant 'growing days' in the spring relative to hatch led to similar results. Our assessment indicates that geese are recovering from habitat degradation by moving to newly colonized locales. However, a warmer climate could negatively affect snow goose populations in the long-run, but it will depend on which seasons warm the fastest. These antagonistic mechanisms will require further study to help predict snow goose population dynamics and manage the trophic cascade they induce. PMID

  9. Environmental Change: Precipitation and N, P, K, mg Fertilization Influences on Crop Yield Under Temperate Climate Conditions

    NASA Astrophysics Data System (ADS)

    László Phd, Dd. M.

    2009-04-01

    Summary: Agroecological quality has a well estabished dependence on climate-rainfall changes because the water problems are pressing. Therefore, there is, growing concern about the potentially wide ranging risks that climate change would have on these key industries as the nature and extent of anticipated changes have become more evident. It also includes changes in land use and in plant production and their management. These changes are unprecedented in terms of both their rate and their spatial extent. Changes in land use (agrotechnics, soil, cultivation, fertility, quality, protection etc.) and in plant production (plant, nutrition, rotation, protection etc.) are currently the main manifestations. As an interdisciplinary problem it is necessary to study such a complex matter in terms of agricultural production. Generally, among natural catastrophes, droughts and floods cause the greatest problems in field crop production. The droughts and the floods that were experienced in Hungary in the early 1980s have drawn renewed attention to the analyses of these problems. New research on climate change-soil-plant systems are focused on yield and yield quality. This paper reports of the climate changes (rainfall); soil (acidic sandy brown forest) properties, mineral N, P, K, Mg fertilisation level and plant interactions on rye (Secale cereale L.), on potato (Solanum tuberosum L.) and on winter wheat (Triticum aestivum L.) yields in a long term field experiment set up at Nyírlugos in north-eastern Hungary under temperate climate conditions in 1962. Results are summarised from 1962 to 1990. Main conclusions were as follows: 1. Rye: a, Experimental years were characterised by frequent extremes of precipitation variabilities and changes. b, By an average year, at a satisfactory fertilisation level (N: 90 kg ha-1 and NP, NK, NPK, NPKMg combinations) the maximum yield reached 3.8 t ha-1. But yield was decreased by 17% and by 52% due to drought and excess rainfall, respectively

  10. Holocene paleoclimate records from a large California estuarine system and its watershed region: linking watershed climate and bay conditions

    NASA Astrophysics Data System (ADS)

    Malamud-Roam, Frances P.; Lynn Ingram, B.; Hughes, Malcolm; Florsheim, Joan L.

    2006-07-01

    The San Francisco Bay-Delta system includes a watershed that covers a large area of California and provides water to two-thirds of the State's population. Climate over the estuary and its watershed in the dry summer months is controlled by the subtropical high which dominates and deflects storms from California. The subtropical high weakens and migrates south as the Aleutian Low strengthens, bringing wet winter storms to the region. Paleoclimatic records from the Bay and its greater watershed, spanning the Holocene, are reviewed here in order to better understand natural variations of precipitation and runoff and the linkages between those variations and the salinity and ecosystems of the estuary. To better understand regional-scale climate patterns, paleoclimate records from coastal California and the Great Basin are also considered. Large fluctuations in climate have occurred during the period of interest, and there is generally good agreement between the paleoclimate records from different regions. Early Holocene climate throughout California was marked by rising temperatures and reduced moisture as seen in fire records from the watershed. This warmth and aridity peaked about 5000-7000 years ago and was followed by a cooling trend, with variable moisture conditions. The Estuary formed relatively rapidly in response to a high rate of sea level rise that dominated the Holocene until about 6000 years ago, and the subsequent reduced rate of inundation allowed vast tidal marshes to form along the edges of the estuary, which have since been recording changes in environmental conditions. The impacts of changing regional climate patterns are experienced in the San Francisco Bay-Delta system, as altered fresh water flows result in altered estuary salinity. For example, approximately 3800 cal yr B.P., records from throughout the state indicate a cool, moist period, and Bay salinity was reduced; this period was followed by a general drying trend throughout California over

  11. Modeling the water-energy nexus under changing energy market and climate conditions: a case study in the Italian Alps

    NASA Astrophysics Data System (ADS)

    Denaro, Simona; Anghileri, Daniela; Castelletti, Andrea; Fumagalli, Elena; Giuliani, Matteo

    2015-04-01

    Climate change and growing population are expected to severely affect freshwater availability by the end of 21th century. Many river basins, especially in the Mediterranean region, are likely to become more prone to periods of reduced water supply, risking considerable impacts on the society, the environment, and the economy, thus emphasizing the need to rethink the way water resources are distributed, managed, and used at the regional and river basin scale. This paradigm shift will be essential to cope with the undergoing global change, characterized by growing water demands and by increasingly uncertain hydrologic regimes. Most of the literature traditionally focused on predicting the impacts of climate change on water resources, while our understanding of the human footprint on the hydrological cycle is limited. For example, changes in the operation of the Alpine hydropower reservoirs induced by socio-economic drivers (e.g., development of renewable energy) have been already observed over the last few years and have produced relevant impacts on multiple water uses due to the altered distribution of water volumes in time and space. Modeling human decisions as well as the links between society and environmental systems becomes key to develop reliable projections on the co-evolution of the coupled human-water systems and deliver robust adaptation strategies. This work contributes a preliminary model-based analysis of the behaviour of hydropower operators under changing energy market and climate conditions. The proposed approach is developed for the San Giacomo-Cancano reservoir system located in the Lake Como catchment. The identification of the current operating policy is supported by input variable selection methods to select the most relevant hydrological and market based drivers to explain the observed release time series. The identified model is then simulated under a set of future scenarios, accounting for both climate and socio-economic change (e

  12. Air conditioning in a tropical climate: Impacts upon European residents in Darwin, Australia

    NASA Astrophysics Data System (ADS)

    Auliciems, A.; Dedear, R.

    1986-09-01

    The efficacy of current practices in air conditioning is investigated in the two monsoonal seasons in Darwin. Assessment is made of atmospheric parameters, clothing, metabolic rate. Some 1000 questionnaires are applied dealing with adaptations, health perceptions and preferences as related to air cooling and ventilation. The findings are discussed with reference to energy balance calculations and current models of psychological control in thermoregulation. The results indicate that Darwin's population is considerably overcooled, and contrary to assumptions and practice, air conditioning is not desired in office buildings during the “Dry”. In the home, air conditioning is not regarded as essential. The indications are that a rationalization of air cooling to comply with natural variability in warmth would lead to a significant reduction in energy consumption, and an overall enhancement to the health and comfort of the population through the greater ventilation rates that would be economically feasible were design temperatures lifted.

  13. The sensitivity of numerically simulated climates to land-surface boundary conditions

    NASA Technical Reports Server (NTRS)

    Mintz, Y.

    1982-01-01

    Eleven sensitivity experiments that were made with general circulation models to see how land-surface boundary conditions can influence the rainfall, temperature, and motion fields of the atmosphere are discussed. In one group of experiments, different soil moistures or albedos are prescribed as time-invariant boundary conditions. In a second group, different soil moistures or different albedos are initially prescribed, and the soil moisture (but not the albedo) is allowed to change with time according to the governing equations for soil moisture. In a third group, the results of constant versus time-dependent soil moistures are compared.

  14. The sensitivity of numerically simulated climates to land-surface boundary conditions

    NASA Technical Reports Server (NTRS)

    Mintz, Y.

    1984-01-01

    Eleven sensitivity experiments that were made with general circulation models to see how land-surface boundary conditions can influence the rainfall, temperature, and motion fields of the atmosphere are discussed. In one group of experiments, different soil moistures or albedos are prescribed as time-invariant boundary conditions. In a second group, different soil moistures or different albedos are initially prescribed, and the soil moisture (but not the albedo) is allowed to change with time according to the governing equations for soil moisture. In a third group, the results of constant versus time-dependent soil moistures are compared. Previously announced in STAR as N83-27536

  15. Evidence of Dry and Cold Climatic Conditions at Glacial Times in Tropical Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Behling, Hermann; Lichte, Martin

    1997-11-01

    Last-glacial paleoenvironments have been reconstructed from a pollen and charcoal record analyzed in organic sediments and dated between ca. 18,000 and >48,000 14C yr B.P. The site is located near the village Catas Altas in the lower highland region of southeastern Brazil. The last-glacial landscape was covered by extensive areas of subtropical grasslands and small areas of gallery forests along the rivers, where tropical semideciduous forests and cerrado ecosystems exist today. The subtropical gallery forests were composed of Araucariaforest trees such as Araucaria angustifolia, Podocarpus, Drimys, Ilex,and Symplocos.Paleofires were frequent. The record indicates that subtropical grassland vegetation, which today is found in patches on the highlands in southern Brazil (especially in the state of Santa Catarina), expanded from southern Brazil to southeastern Brazil, over a distance of more than 750 km, from latitudes of about 28° S to at least 20° S. The completely different last-glacial environment, in comparison to the present-day environment, reflects a dry and cold climate with strong frosts during the winter months. Temperatures of 5°-7°C below those of the present are inferred for the last glaciation.

  16. Complementarity effects on tree growth are contingent on tree size and climatic conditions across Europe

    PubMed Central

    Madrigal-González, Jaime; Ruiz-Benito, Paloma; Ratcliffe, Sophia; Calatayud, Joaquín; Kändler, Gerald; Lehtonen, Aleksi; Dahlgren, Jonas; Wirth, Christian; Zavala, Miguel A.

    2016-01-01

    Neglecting tree size and stand structure dynamics might bias the interpretation of the diversity-productivity relationship in forests. Here we show evidence that complementarity is contingent on tree size across large-scale climatic gradients in Europe. We compiled growth data of the 14 most dominant tree species in 32,628 permanent plots covering boreal, temperate and Mediterranean forest biomes. Niche complementarity is expected to result in significant growth increments of trees surrounded by a larger proportion of functionally dissimilar neighbours. Functional dissimilarity at the tree level was assessed using four functional types: i.e. broad-leaved deciduous, broad-leaved evergreen, needle-leaved deciduous and needle-leaved evergreen. Using Linear Mixed Models we show that, complementarity effects depend on tree size along an energy availability gradient across Europe. Specifically: (i) complementarity effects at low and intermediate positions of the gradient (coldest-temperate areas) were stronger for small than for large trees; (ii) in contrast, at the upper end of the gradient (warmer regions), complementarity is more widespread in larger than smaller trees, which in turn showed negative growth responses to increased functional dissimilarity. Our findings suggest that the outcome of species mixing on stand productivity might critically depend on individual size distribution structure along gradients of environmental variation. PMID:27571971

  17. Measuring environmental impact by real time laser differential displacement technique in simulated climate conditions

    NASA Astrophysics Data System (ADS)

    Tornari, Vivi; Bernikola, Eirini; Tsigarida, Nota; Hatzigiannakis, Kostas; Andrianakis, Michalis; Leissner, Johanna

    2015-06-01

    Environmental impact on artworks has always been a big issues for preservation of Cultural Heritage. Nowadays with the climate change it is experienced a slow but steady process of temperature increase affecting relative humidity which fluctuates while materials attempt to keep moisture balance. During repetitive equilibrium courses fatigue accumulates endangering the structural integrity prior to fracture. Assessing the risk imposed by the fluctuation allow preventive actions to take place and avoid interventive restoration action after fracture. A methodology is presented employing full-field interferometry by surface probing illumination based on direct realtime recording of surface images from delicate hygroscopic surfaces as they deform to dimensionally respond to relative humidity (RH) changes. The developed methodology aims to develop an early stage risk indicator tool to allow preventive measures directly through surface readings. The presented study1 aiming to experimentally highlight acclimatisation structural phenomena and to verify assumed standards in RH safety range based on the newly introduced concept of deformation threshold value is described and demonstrated with indicative results.

  18. Influence of climatic conditions on production of Stipa-Bouteloua prairie over a 50-year period

    SciTech Connect

    Smoliak, S.

    1986-03-01

    Range forage yields obtained over a 50-year period at the Research Substation near Manyberries in southeastern Alberta were analyzed in relation to several climatic factors. The basic variables were precipitation, pan evaporation, temperature, hours of sunlight, and wind velocity. The precipitation from April through July was highly correlated with range forage production and this relationship could be utilized to predict the annual forage production by 1 August each year. A slightly better correlation was obtained when range forage production was related to the total of the previous September plus the current April through July precipitation. Pan evaporation totals, mean temperature, and hours of sunlight were negatively correlated with forage production, while wind velocity during the growing season showed a low relationship to forage production. Stepwise regression analysis showed that the inclusion of May and June mean temperatures with June and July precipitation accounted for 63% of the variation in range forage production. The predicted forage yield would be useful in making management decisions or adjustments, especially during drought periods, while the long-term forage yield data can be utilized in range forage models or in validating their effectiveness.

  19. Phosphorus Concentrations in Above Ground Plant Biomass under Changing Climate Conditions

    NASA Astrophysics Data System (ADS)

    Selvin, C.; Paytan, A.; Roberts, K.

    2013-12-01

    The Jasper Ridge Global Change Experiment explores the effects of climate change on annual grasslands with different combinations of elevated or ambient levels of carbon dioxide, heat, precipitation, and nitrate deposition. The nested split-plot design allows for analysis of each variable, combinations of variables, and secondary effects. In this study, plant nutrient levels in homogenized above ground biomass are analyzed to assess the utility of this parameter as a tool to describe the response of an ecosystem to environmental changes. Total phosphorus concentrations showed considerable variability within treatment (n=8) and therefore no significant differences between treatments (n=16) is found. Carbon and nitrogen concentrations in bulk above ground biomass are being analyzed to determine nitrogen and carbon ratios and further elucidate the environmental response of phosphorus levels in plants to the modified parameters. P concentrations and elemental ratios will also be related to other parameters such as soil humidity, microbial biomass, enzyme activity, and plant diversity to determine the parameters influencing P content in the biomass.

  20. [Chinese pine tree ring width chronology and its relations to climatic conditions