Journal of Paleolimnology 31: 275–293, 2004. # 2004 Kluwer Academic Publishers. Printed in the Netherlands. 275 Late Holocene lake level dynamics inferred from magnetic susceptibility and stable oxygen isotope data: Lake Elsinore, southern California (USA) Matthew E. Kirby1,*, Christopher J. Poulsen2, Steve P. Lund3, William P. Patterson4, Liam Reidy5 and Douglas E. Hammond3 1Department of Geological Sciences, California State University, Fullerton, Fullerton, CA 92834, USA; 2Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109, USA; 3Department of Earth Sciences, University of Southern California, Los Angeles, CA 90089, USA; 4Department of Geological Sciences, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E2; 5Department of Geography, University of California, Berkeley, 507 McCone Hall, Berkeley, CA 94720, USA; *Author for correspondence (e-mail:
[email protected]) Received 25 March 2003; accepted 3 July 2003 Key words: Lake Elsinore, Lake level, Isotopes, Magnetic susceptibility, Precipitation, Southern California Abstract Southern California faces an imminent freshwater shortage. To better assess the future impact of this water crisis, it is essential that we develop continental archives of past hydrological variability. Using four sediment cores from Lake Elsinore in Southern California, we reconstruct late Holocene (3800 calendar years B.P.) hydrological change using a twentieth-century calibrated, proxy methodology. We compared magnetic susceptibility from Lake Elsinore deep basin sediments, lake level from Lake Elsinore, and regional winter precipitation data over the twentieth century to calibrate the late Holocene lake sediment record. The comparison revealed a strong positive, first-order relationship between the three variables. As a working hypothesis, we suggest that periods of greater precipitation produce higher lake levels.