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These data are netcdf files of the projected timing of the onset of thermal stress severe enough (>8 Degree Heating Weeks) to cause coral bleaching 2x per decade and 10x per decade (annual) under emissions scenarios RCP8.5 and RCP4.5. The projected timing (a year between 2006 and 2100) is the data value. Values are only shown for the ~60,000 four-km pixels where coral reefs are known to occur.
Abstract (from http://www.sciencedirect.com/science/article/pii/S1873965215000110): The goal of this study was to assess the importance of the 2007 sea ice retreat for hydrologic conditions on the Alaskan North Slope, and how this may have influenced the outbreak of tundra fires in this region. This study concentrates on two years, 2007 and 1996, with different arctic sea ice conditions and tundra fire activity. The year of 2007 is characterized by a low summer sea ice extent (second lowest) and high tundra fire activity, while 1996 had high sea ice extent, and few tundra fires. Atmospheric lateral boundary forcing from the NCEP/NCAR Reanalysis drove the Weather Research and Forecast (WRF) model, along with varying...
The Hawaiian Islands are home to a variety of native species that have been subject to numerous threats including development of habitat for human use, predation by introduced herbivores, and competition with invasive plant species. In addition to these threats global climate change is expected to increase temperature and alter patterns of precipitation in Hawaii. This project models the relative vulnerability of native plant species to the effects of climate change, in order to assist resource managers in effectively allocating limited resources to efficiently preserve and protect current and future habitat for native plants. We modeled vulnerability by creating an expert system – a network model linking biological...
Abstract (from http://www.bioone.org/doi/abs/10.2112/JCOASTRES-D-13-00202.1): Traditional long-term (decadal) and large-scale (hundreds of kilometers) shoreline change modeling techniques, known as single transect, or ST, often overfit the data because they calculate shoreline statistics at closely spaced intervals along the shore. To reduce overfitting, recent work has used spatial basis functions such as polynomials, B splines, and principal components. Here, we explore an alternative to such basis functions by using regularization to reduce the dimension of the ST model space. In our regularized-ST method, traditional ST is an end member of a continuous spectrum of models. We use an evidence information criterion...
Abstract: P-band interferometric synthetic aperture radar (InSAR) data at 5 m resolution from Kahiltna Glacier, the largest glacier in the Alaska Range, Alaska, USA, show pronounced spatial variation in penetration depth, δ P. We obtained δ P by differencing X- and P-band digital elevation models. δ P varied significantly over the glacier, but it was possible to distinguish representative zones. In the accumulation area, δ P decreased with decreasing elevation from 18±3 m in the percolation zone to 10±4 m in the wet snow zone. In the central portion of the ablation area, a location free of debris and crevasses, we identified a zone of very high δ P (34±4 m) which decreased at lower elevations (23±3 m in bare ice...
Abstract (from http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0088.1): A comprehensive understanding of the spatial, seasonal, and diurnal patterns in cloud cover frequency over the Hawaiian Islands was developed using high-resolution image data from the National Aeronautics and Space Administration’s Moderate Resolution Imaging Spectroradiometer (MODIS) sensors aboard the Terra and Aqua satellites. The Terra and Aqua MODIS cloud mask products, which provide the confidence that a given 1-km pixel is unobstructed by cloud, were obtained for the entire MODIS time series (10-plus years) over the main Hawaiian Islands. Monthly statistics were generated from the daily cloud mask data, including mean cloud cover...
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This data set describes the predicted daily climate (temperature and rainfall) for low, mid, and high-elevations on Mona Loa, Island of Hawaii from 2098-2100. Climate predictions are based on 3 alternative climate scenarios (RCP 4.5, A1B, and RCP 8.5) - see Liao et al. 2015 for more details and climate references. The predicted daily risk of susceptible Hawaiian honeycreepers are based on the daily climate data, mosquito abundance and other factors. Also see Samuel et al. 2011 The dynamics, transmission, and population impacts of avian malaria in native Hawaiian birds: a modeling approach. Ecological Applications 21:2960-2973 for description of the epidemiological model used for avian malaria risk predictions.
Abstract (from http://onlinelibrary.wiley.com/doi/10.1111/gcb.12875/abstract): Permafrost thaw can alter the soil environment through changes in soil moisture, frequently resulting in soil saturation, a shift to anaerobic decomposition, and changes in the plant community. These changes, along with thawing of previously frozen organic material, can alter the form and magnitude of greenhouse gas production from permafrost ecosystems. We synthesized existing methane (CH 4) and carbon dioxide (CO 2) production measurements from anaerobic incubations of boreal and tundra soils from the geographic permafrost region to evaluate large-scale controls of anaerobic CO 2 and CH 4 production and compare the relative importance...
Abstract (from http://onlinelibrary.wiley.com/doi/10.1002/2016EF000479/full): Glacier hypsometry provides a first-order approach for assessing a glacier's response to climate forcings. We couple the Randolph Glacier Inventory to a suite of in situ observations and climate model output to examine potential change for the ∼27,000 glaciers in Alaska and northwest Canada through the end of the 21st century. By 2100, based on Representative Concentration Pathways (RCPs) 4.5–8.5 forcings, summer temperatures are predicted to increase between +2.1 and +4.6°C, while solid precipitation (snow) is predicted to decrease by −6 to −11%, despite a +9 to +21% increase in total precipitation. Snow is predicted to undergo a pronounced...
Abstract (from http://climatechangeresponses.biomedcentral.com/articles/10.1186/s40665-016-0015-2): Background Detailed assessments of species responses to climate change are uncommon, owing to the limited nature of most ecological and local climate data sets. Exceptions, such as the case of the Haleakalā silversword, can provide important insights into the complexity of biological responses to changing climate conditions. We present a time series of decadal population censuses, combined with a pair of early population projections, which together span the past 80 years of demographic history for this alpine plant. Results The time series suggests a strong population recovery from the 1930s through the 1980s, likely...
A cocktail of land-based sources of pollution threatens coral reef ecosystems, and addressing these has become a key management and policy challenge in the State of Hawaii, other US territories, and globally. In West Maui, Hawai'i, nearly one quarter of all living corals were lost between 1995 and 2008. Onsite disposal systems (OSDS) for sewage leak contaminants into drinking water sources and nearshore waters. In recognition of this risk, the Hawaii State Department of Health (DOH) is prioritizing areas for cesspool upgrades. Independently, we applied a decision analysis process to identify priority areas to address sewage pollution from OSDS in West Maui, with the objective of reducing nearshore coral reef exposure...
There is growing evidence that the rate of warming is amplified with elevation, such that high-mountain environments experience more rapid changes in temperature than environments at lower elevations. Elevation-dependent warming (EDW) can accelerate the rate of change in mountain ecosystems, cryospheric systems, hydrological regimes and biodiversity. Here we review important mechanisms that contribute towards EDW: snow albedo and surface-based feedbacks; water vapour changes and latent heat release; surface water vapour and radiative flux changes; surface heat loss and temperature change; and aerosols. All lead to enhanced warming with elevation (or at a critical elevation), and it is believed that combinations...
Climate policy developers and natural resource managers frequently desire high-resolution climate data to prepare for future effects of climate change. But they face a long-standing problem: the vast majority of climate models have been run at coarse resolutions—from hundreds of kilometers in global climate models (GCMs) down to 25–50 kilometers in regional climate models (RCMs).
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This landcover raster was generated through a Random Forest predictive model developed in R using a combination of image-derived and ancillary variables, and field-derived training points grouped into 18 classes. Overall accuracy, generated internally through bootstrapping, was 75.5%. A series of post-modeling steps brought the final number of land cover classes to 28.
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Training points collected in the field between 2012 and 2013 were grouped into 18 classes: Forested Burn (66), Foothill Woodland Steppe Transition (73), Greasewood Flat (73), Greasewood Steppe (239), Greasewood Sage Steppe (277), Great Plains Badlands (166), Great Plains Riparian (255), Low Density Sage Steppe (776), Medium Density Sage Steppe (783), Mixed Grass Prairie (555), Mixed Grass Prairie Burned (278), Ponderosa Pine Woodland and Shrubland (512), Riparian Floodplain (223), Semi-Desert Grassland (103), Sparsely Vegetated Mixed Shrub (252), Silver Sage Flat (70) , Silver Sage Steppe (64), and Water (246). When insufficient field data were available for a class, we augmented it through photointerpretation of...
Abstract (from http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0174045): Several studies have projected increases in drought severity, extent and duration in many parts of the world under climate change. We examine sources of uncertainty arising from the methodological choices for the assessment of future drought risk in the continental US (CONUS). One such uncertainty is in the climate models’ expression of evaporative demand (E0), which is not a direct climate model output but has been traditionally estimated using several different formulations. Here we analyze daily output from two CMIP5 GCMs to evaluate how differences in E0 formulation, treatment of meteorological driving data, choice of GCM,...
The National Climate Assessment summarizes the impacts of climate change on the United States, now and in the future. A team of more than 300 experts guided by a 60-member Federal Advisory Committee produced the report, which was extensively reviewed by the public and experts, including federal agencies and a panel of the National Academy of Sciences. The report can be explored interactively at http://nca2014.globalchange.gov.
Abstract (from ScienceDirect): Paleohydrologic records can provide unique, long-term perspectives on streamflow variability and hydroclimate for use in water resource planning. Such long-term records can also play a key role in placing both present day events and projected future conditions into a broader context than that offered by instrumental observations. However, relative to other major river basins across the western United States, a paucity of streamflow reconstructions has to date prevented the full application of such paleohydrologic information in the Upper Missouri River Basin. Here we utilize a set of naturalized streamflow records for the Upper Missouri and an expanded network of tree-ring records...


map background search result map search result map Charles M. Russell National Wildlife Refuge Spot Landcover Classification in Relation to Greater Sage Grouse Training Points Predicted climate and avian malaria risk to Hawaiian honeycreepers on the Island of Hawaii from 2098-2100 Predicted climate and avian malaria risk to Hawaiian honeycreepers on the Island of Hawaii from 2098-2100 Training Points Charles M. Russell National Wildlife Refuge Spot Landcover Classification in Relation to Greater Sage Grouse