California Paleo-Streamflow Records from the Last Interglacial

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

ABSTRACT California Paleo-streamflow records from the Last Interglacial B. Lynn Ingram, University of California, Berkeley The goal of this research project is to assess annual average and seasonal salinity and river inflow to San Francisco Bay during the Last Interglacial (ca 130 to 115 ka). The Bay, located at the mouth of the San Joaquin-Sacramento river system, receives river discharge from a drainage basin that integrates precipitation and runoff over a watershed covering 40% of California. Previous work shows that the Last Interglacial was warmer, with a higher sea level, than the present interglacial. This study will examine how these previous changes have impacted a major, now highly urbanized, estuary. This will be accomplished by isotopic analyses of mollusk shells and foraminifers, as well as stratigraphic and paleontological analysis, of estuarine sediments cored in the northern reach of San Francisco Bay (near the delta). In this study we hope to provide data on the natural variability of average intra-annual inflow during the Last Interglacial. We also wish to assess the amplitude and seasonal distribution of inflow during this warmer period, in order to predict what affect future global warming may have on San Francisco Bay estuarine system.