HR: 0800h
AN: C51A-1016    [Abstracts]
TI: Evidence From Tibetan Ice Core Records Concerning Climatic Influences on the Asian Monsoon During the 19th Century
AU: * Davis, M E
EM: davis.3@osu.edu
AF: Byrd Polar Research Center, The Ohio State University, Scott Hall 1090 Carmack Rd., Columbus, OH 43210 United States
AU: Thompson, L G
EM: thompson.3@osu.edu
AF: Byrd Polar Research Center, The Ohio State University, Scott Hall 1090 Carmack Rd., Columbus, OH 43210 United States
AU: Yao, T
EM: tdyao@itpcas.ac.cn
AF: The Institute of Tibetan Plateau Research, 260 Donggang West Rd., Lanzhou, 730000 China
AU: Wang, N
EM: nlwang@ns.lzb.ac.cn
AF: Key Laboratory of Ice Core and Cold Regions Environment, 260 Donggang West Rd., Lanzhou, 730000 China
AB: Teleconnections between the North Atlantic and Asian monsoon regions on orbital and suborbital time scales have been documented in many proxy climate records. Here, the influence of this linkage on snow accumulation across the Tibetan Plateau during the latter part of the Little Ice Age (LIA) is examined using high-resolution ice core records from four sites. Since the end of the LIA ($\sim$1880), the net accumulation (A$_{n}$) time series from the Dasuopu ice cap ($28\deg$N, $85\deg$E) in the Himalayas has resembled the north central India summer monsoon rainfall (NCISMR) record. However, from $\sim$1810 to $\sim$1880 the ice core A$_{n}$ values were 50% higher than those of the NCISMR. This increase during the 19th century, which was contemporaneous with lower temperatures in the North Atlantic and a persistently negative early winter North Atlantic Oscillation (NAO) index, is argued to be the result of increased winter snowfall in the central Himalayas. In contrast to Dasuopu, the A$_{n}$ records from three sites to the north (Dunde at $38\deg$N, $96\deg$E, Puruogangri at $34\deg$N, $90\deg$E and Guliya at $35\deg$N, $81\deg$E) show lower rates during most of the 19th century. Although these glaciers receive a significant portion of their precipitation during the summer from a variety of competing weather systems besides the monsoon, such as mid-latitude westerlies and local thermally-induced storms, their accumulation records show similarities to the reconstructed all-India summer monsoon rainfall (AISMR) record over the last two centuries. The lower accumulation rates during the 19th century in these three ice core profiles and in the AISMR are possibly linked to the Dasuopu A$_{n}$ record (which in turn is linked to climate changes in the North Atlantic) by the inverse relationship between the Himalayan winter snow amounts and the subsequent summer monsoon intensity.
DE: 3344 Paleoclimatology
DE: 3354 Precipitation (1854)
DE: 1863 Snow and ice (1827)
DE: 1620 Climate dynamics (3309)
SC: Cryosphere [C]
MN: 2004 AGU Fall Meeting