Skip to main content

Person

Dennis P Lettenmaier

This recorded presentation is from the April 17, 2014 workshop for the "Integrated Scenarios of the Future Northwest Environment" project. The recording is available on YouTube. The Integrated Scenarios project is an effort to understand and predict the effects of climate change on the Northwest's climate, hydrology, and vegetation. The project was funded by the Northwest Climate Science Center and the Climate Impacts Research Consortium.
Abstract (from http://onlinelibrary.wiley.com/doi/10.1002/hyp.10964/abstract): While the effects of land use change in urban areas have been widely examined, the combined effects of climate and land use change on the quality of urban and urbanizing streams have received much less attention. We describe a modelling framework that is applicable to the evaluation of potential changes in urban water quality and associated hydrologic changes in response to ongoing climate and landscape alteration. The grid-based spatially distributed model, Distributed Hydrology Soil Vegetation Model-Water Quality (DHSVM-WQ), is an outgrowth of DHSVM that incorporates modules for assessing hydrology and water quality in urbanized watersheds...
Data Sources, inputs, parameters, and code for the MACA-VIC project final report. Consists of 3 tasks: 1. Consists of comparing results of the indexing method MTCLIM to estimate incoming short and long wave radiation, to observations, to BSRN station data, and to three Ameriflux towers in the Pacific Northwest. 2. Reports on forcing VIC with downscaled GCM forcings, with variations in two forcing variables: downward shortwave radiation (rad) and specific humidity (qair). For this task we consider the MACA downscaling method. Three cases are reported: a) both variables are downscaled; b) rad is indexed and qair is downscaled; c) rad is downscaled and qair is indexed. 3. Reports on forcing VIC with downscaled...
We assessed the performance of the MTCLIM scheme for estimating downward shortwave (SWdown) radiation and surface humidity from daily temperature range (DTR), as well as several schemes for estimating downward longwave radiation (LWdown), at 50 Baseline Solar Radiation Network stations globally. All of the algorithms performed reasonably well under most climate conditions, with biases and mean absolute errors generally less than 3% and 20%, respectively, over more than 70% of the global land surface. However, estimated SWdown had a bias of −26% at coastal sites, due to the ocean's moderating influence on DTR, and in continental interiors, SWdown had an average bias of −15% in the presence of snow, which was reduced...
thumbnail
Projecting Future Climate, Vegetation, and Hydrology in the Pacific Northwest
In the Pacific Northwest, temperatures are projected to increase 2-15°F by 2100. Winters are expected to become wetter and summers could become drier. Snowpack will likely decrease substantially, and snowmelt runoff may occur earlier in the year. Wildfires are projected to become more frequent and severe, and forest types are expected to change from maritime evergreen to subtropical mixed-woodlands. Because the impacts of climate change vary from place to place, regionally-specific climate projections are critical to help farmers, foresters, city planners, public utility providers, and fish and wildlife managers plan for how to best manage resources. However, the models that are used to project changes in climate...
ScienceBase brings together the best information it can find about USGS researchers and offices to show connections to publications, projects, and data. We are still working to improve this process and information is by no means complete. If you don't see everything you know is associated with you, a colleague, or your office, please be patient while we work to connect the dots. Feel free to contact sciencebase@usgs.gov.