Type 1 - The Dynamic Watershed and Coastal Ocean: Predicting Their Biogeochemical Linkages and Variability over Decadal Time Scales

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

This pilot project aims to couple regional-scale, earth system models for watersheds, the coastal ocean and atmosphere, and embed them in a global climate model. This approach can used to ask the following questions: Can the regional model results capture watershed-forced, decadal-scale variation in the coastal ocean? Can the coupled models provide useful information for community managers with responsibility for watershed and coastal locales? This project focuses on the Eel River watershed in Northern California, which discharges into the North Pacific near Cape Mendocino. Its annual discharge is small, but its sediment yield is the highest for its drainage area in the entire continental U.S. Scientists have studied the Eel River intensively over the last three decades, so important information on the watershed, river, and the coastal ocean is available. Nevertheless, these individual studies have commonly extended for only limited periods, or over restricted regions, so a comprehensive, interdisciplinary, data-based picture is incomplete. Decadal variability and irregular regional Fluctuations are the main foci of the project. Over decadal scales, differences between high flood periods and intervals of intense drought will be examined. In particular, by producing hindcasts for these extreme situations, the investigators will test whether the coupled models adequately predicted both circumstances (and the differences between them). Over regional spatial domains in coastal Northern California, the proposed models will be examined to determine if it can distinguish properties of watershed systems separated in space, but subjected to similar modes of weather. Intellectual Merit: This project is the first comprehensive attempt to couple and to unify models from the watershed to the ocean, and then embed these linked models within a global climate model. The high resolution of the watershed models will allow the investigators to determine the extent to which watershed environmental and ecological data enhances the predictive capability of the connected models. The watershed models will be scrutinized for their ability to simulate transport of nutrients to the coastal ocean. This will clarify the role terrestrial processes play in controlling coastal ocean productivity when oceanic features (like coastal upwelling) are not prominent. Broader Impacts: Planning and management efforts in the communities within watersheds and coastal locales must incorporate the potential for climate change. Our modeling endeavors can provide information to political, business, and cultural leaders that addresses possible changes that their groups and localities may face. Accordingly, the collaborators with such leaders will be pursued. Moreover, the modeling results will be designed to be user-friendly and will be made available to the adjacent Northern California communities. Finally, the Angelo Reserve, a member of the University of California Natural Reserve System, and the base for much of the aquatic ecology investigations in the Eel River watershed, is used by many UC Berkeley classes from a variety of disciplines. The modeling results from this project will open another window for further out-of-classroom experience.