HR: 11:35h
AN: PP22A-06    [Abstracts]
TI: Late Holocene Temperature and Aridity Changes From Lake Qinghai, China
AU: * Huang, Y
EM: Yongsong_Huang@brown.edu
AF: Brown University, Department of Geological Sciences, 324 Brook St., Providence, RI 02912
AU: Liu, Z
EM: zhonghui_liu@brown.edu
AF: Brown University, Department of Geological Sciences, 324 Brook St., Providence, RI 02912
AU: Henderson, A
EM: ahenders@life.uiuc.edu
AF: University of Illinois, Department of Plant Biology, 505 South Goodwin Avenue, Urbana, IL 61801
AB: The presence of abundant alkenones in saline waters of Qinghai Lake, China, provides a proxy for quantitative reconstruction of lake water temperature history. We have generated a high-resolution alkenone-temperature record for the last 4,000 years. These estimates recorded about 1°C change in mean annual temperature or 2 °C change in summer month temperature in the late Holocene. Though small, these changes greatly exceeded the analytical error (0.15°C), and they consistently show warm and cold intervals which could possibly relate to Little Ice Age, Medieval Warm Period, Dark Ages Cold Period, and Roman Warm Period. Alkenone C37:4 production was more important than their counterparts (C37:3 and C37:2) during warm periods, probably indicating that this area was also wet during warm periods. Carbonate oxygen isotopes and fatty acid hydrogen isotopes will be also generated to verify the aridity changes inferred from alkenone records, and more importantly, to separate temperature and effective moisture (P/E) effects in carbonate oxygen isotopes.
DE: 0473 Paleoclimatology and paleoceanography (3344, 4900)
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
SC: Paleoceanography and Paleoclimatology [PP]
MN: Fall Meeting 2005