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Abstract (from http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0199.1): Future snowfall and snowpack changes over the mountains of Southern California are projected using a new hybrid dynamical–statistical framework. Output from all general circulation models (GCMs) in phase 5 of the Coupled Model Intercomparison Project archive is downscaled to 2-km resolution over the region. Variables pertaining to snow are analyzed for the middle (2041–60) and end (2081–2100) of the twenty-first century under two representative concentration pathway (RCP) scenarios: RCP8.5 (business as usual) and RCP2.6 (mitigation). These four sets of projections are compared with a baseline reconstruction of climate from 1981 to 2000....
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To understand potential climate change impacts on ecosystems, water resources, and numerous other natural and managed resources, climate change data and projections must be downscaled from coarse global climate models to much finer resolutions and more applicable formats. This project conducted comparative analyses to better understand the accuracy and properties of these downscaled climate simulations and climate-change projections. Interpretation, guidance and evaluation, including measures of uncertainties, strengths and weaknesses of the different methodologies for each simulation, can enable potential users with the necessary information to select and apply the models.
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The goal of this project was to: (a) archive the relevant AR5 model output data for the southwest region; (b) downscale daily temperature and precipitation to 12 X 12 km cell spatial resolution over the Southwest; (c) assess the precision (degree of agreement) of the simulated models; (d) assess the direction and magnitude of change in projections between AR4 and AR5, as well as assess projections of key extreme climatic events (i.e., extreme drought, extreme seasonal precipitation, extreme high and low temperature events); and (e) assess critical ecosystem impacts (i.e., climate water deficit and fire; hydrological condition of major river systems; impacts on highly valued species).
Abstract (from http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-14-00196.1): In this study (Part I), the mid-twenty-first-century surface air temperature increase in the entire CMIP5 ensemble is downscaled to very high resolution (2 km) over the Los Angeles region, using a new hybrid dynamical–statistical technique. This technique combines the ability of dynamical downscaling to capture finescale dynamics with the computational savings of a statistical model to downscale multiple GCMs. First, dynamical downscaling is applied to five GCMs. Guided by an understanding of the underlying local dynamics, a simple statistical model is built relating the GCM input and the dynamically downscaled output. This statistical...
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The goal of this project was to examine how temperature and precipitation could change by the mid 21st century over the greater Los Angeles region. Major findings for temperature are: (1) large variability in the magnitude exists among downscaled global climate model projections over LA, but all predict warming; (2) warming is smaller over the ocean and coastal zone, but larger in the mountain areas and inland; (3) ensemble mean warming in all parts of the domain is significantly outside the range of historical variability, meaning the change will be detectable. Major findings for precipitation are: (1) large variability in both sign and magnitude exists among downscaled global climate model precipitation projections...
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In California, the near-shore area where the ocean meets the land is a highly productive yet sensitive region that supports a wealth of wildlife, including several native bird species. These saltmarshes, mudflats, and shallow bays are not only critical for wildlife, but they also provide economic and recreational benefits to local communities. Today, sea-level rise, more frequent and stronger storms, saltwater intrusion, and warming water temperatures are among the threats that are altering these important habitats. To support future planning and conservation of California’s near-shore habitats, researchers examined current weather patterns, elevations, tides, and sediments at these sites to see how they affect...
Categories: Project; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: 2012, Bolinas Lagoon, CA, CASC, California, All tags...
Abstract (from http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-14-00197.1): Using the hybrid downscaling technique developed in part I of this study, temperature changes relative to a baseline period (1981–2000) in the greater Los Angeles region are downscaled for two future time slices: midcentury (2041–60) and end of century (2081–2100). Two representative concentration pathways (RCPs) are considered, corresponding to greenhouse gas emission reductions over coming decades (RCP2.6) and to continued twenty-first-century emissions increases (RCP8.5). All available global climate models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) are downscaled to provide likelihood and uncertainty estimates....
Southern California is a biodiversity hotspot and home to over 23 million people. Over recent decades the annual wildfire area in the coastal southern California region has not significantly changed. Yet how fire regime will respond to future anthropogenic climate change remains an important question. Here, we estimate wildfire probability in southern California at station scale and daily resolution using random forest algorithms and downscaled earth system model simulations. We project that large fire days will increase from 36 days/year during 1970–1999 to 58 days/year under moderate greenhouse gas emission scenario (RCP4.5) and 71 days/year by 2070–2099 under a high emission scenario (RCP8.5). The large fire...
Categories: Publication; Types: Citation


    map background search result map search result map Analysis of Downscaled Climate Simulations and Projections and Their Use in Decision Making for the Southwest Assessment of Available Climate Models and Projections for the Southwest Region Effects of Sea-Level Rise and Extreme Storms on California Coastal Habitats: Part 1 Climate Change in the Los Angeles Region: Temperature and Precipitation Climate Change in the Los Angeles Region: Temperature and Precipitation Effects of Sea-Level Rise and Extreme Storms on California Coastal Habitats: Part 1 Analysis of Downscaled Climate Simulations and Projections and Their Use in Decision Making for the Southwest Assessment of Available Climate Models and Projections for the Southwest Region