From ceginfo@u.washington.edu Mon Aug 11 10:01:36 2003 Received: from mxu1.u.washington.edu (mxu1.u.washington.edu [140.142.32.132]) by lists.u.washington.edu (8.12.9+UW03.06/8.12.9+UW03.06) with ESMTP id h7BH1a2x032572 for ; Mon, 11 Aug 2003 10:01:36 -0700 Received: from mxout5.cac.washington.edu (mxout5.cac.washington.edu [140.142.32.135]) by mxu1.u.washington.edu (8.12.9+UW03.06/8.12.9+UW03.06) with ESMTP id h7BH1WdM016760 (version=TLSv1/SSLv3 cipher=EDH-RSA-DES-CBC3-SHA bits=168 verify=NO); Mon, 11 Aug 2003 10:01:32 -0700 Received: from homer13.u.washington.edu (homer13.u.washington.edu [140.142.8.13]) by mxout5.cac.washington.edu (8.12.9+UW03.06/8.12.9+UW03.06) with ESMTP id h7BH1Rin031110; Mon, 11 Aug 2003 10:01:28 -0700 Received: from localhost (ceginfo@localhost) by homer13.u.washington.edu (8.12.9+UW03.06/8.12.9+UW03.06) with ESMTP id h7BH1Rt5019344; Mon, 11 Aug 2003 10:01:27 -0700 Date: Mon, 11 Aug 2003 10:01:27 -0700 (PDT) From: Civil and Environmental Engineering To: faculty@ce.washington.edu, , , , Subject: Final Ph.D. Exam for Andrew Wood Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Uwash-Spam: Gauge=IIIIII, Probability=6%, Report='__HAS_MSGID, __SANE_MSGID, QUOTED_EMAIL_TEXT, LINES_OF_YELLING' The final examination for the Ph.D. degree for Aandrew Wood will be held on Monday, August 18, 2003 in 264 Wilcox at 1:00. -------------------------------------------------------------------------- > USING CLIMATE MODEL ENSEMBLE FORECASTS FOR SEASONAL HYDROLOGIC PREDICTION > Andrew W. Wood > > [Professor Dennis P. Lettenmaier (Chair) > Department of Civil and Environmental Engineering] > > ABSTRACT > Seasonal hydrologic forecasting has long played an invaluable role in the > development and use of water resources. Despite notable advances in the > science and practice of climate prediction, current approaches of > hydrologists and water managers largely fail to incorporate seasonal > climate forecast information that has become operationally available > during the last decade. This study is motivated by the view that a > combination of hydrologic and climate prediction methods affords a new > opportunity to improve hydrologic forecast skill. A relatively direct > statistical approach for achieving this combination (i.e., downscaling) > was demonstrated that used ensemble climate model forecasts with a six > month lead time produced by the NCEP/CPC Global Spectral Model (GSM) as > input to the macroscale Variable Infiltration Capacity hydrologic model > to produce ensemble runoff and streamflow forecasts. The approach > involved the bias correction of climate model precipitation and > temperature fields, and spatial and temporal disaggregation from monthly > climate model scale (about 2 degrees latitude by longitude) fields to > daily hydrology model scale (1/8 degrees) inputs. A qualitative > evaluation of the approach in the eastern U.S. suggested that it was > successful in translating climate forecast signals to local hydrologic > variables and streamflow, but that the dominant influence on forecast > results tended to be persistence in initial hydrologic conditions. The > suitability of the statistical downscaling approach for supporting > hydrologic simulation was then assessed (using a continuous retrospective > 20-year climate simulation from the DOE Parallel Climate Model) relative > to dynamical downscaling via a regional, meso-scale climate model. The > statistical approach generally outperformed the dynamical approach, in > that the dynamical approach alone required additional bias-correction to > reproduce the retrospective hydrology as well as the statistical > approach. Finally, using 21 years of retrospective forecasts for the > western U.S., the skill of the GSM-based hydrologic forecasts was assessed > relative to NWS Extended Streamflow Prediction (ESP) method forecasts. > Because of unexceptional GSM climate forecasts, the GSM-based and ESP > hydrologic forecasts generally showed similar skill. During strong ENSO > anomalies, however, GSM-based forecasts yielded higher forecast skill in > the Sacramento-San Joachin and Columbia River basins, but lower skill in > the Colorado and upper Rio Grande River basins. > > <|--------------------------------------------------------------------|> > | Andrew W. Wood 206-685-1796 (w/lab) | > | University of Washington 206-910-3938 (cell) | > | Civil and Env. Engineering 503-280-8763 (home) | > | Box 352700 206-685-3836 (fax) | > | Seattle, WA 98195-2700 http://www.ce.washington.edu/~aww/ | > <|--------------------------------------------------------------------|> > > > .