Joint Meteorology & IPRC Seminar

"Tibetan Plateau Warming Trend and Precipitation Changes in East Asia"

By: Dr. Bin Wang
Professor
Department of Meteorology & IPRC
University of Hawaii

ABSTRACT:
Using 90 weather station records, we show that the surface air temperatures averaged on the Tibetan Plateau (TP) have increased by about 1.8oC over the past 50 years. This estimate is significantly larger than the trend reported in IPCC AR4 assessment. The precipitation pattern that is projected as a result of this warming resembles the leading pattern of precipitation variations in East Asia (EA) for the same period. Numerical experiments with atmospheric general circulation models show that atmospheric heating induced by the rising TP temperatures can enhance East Asian subtropical frontal rainfall. The mechanism of the linkage is found to be through two distinct Rossby wave trains and the isentropic uplift to the east of the TP, which together deform the western Pacific Subtropical High and enhance moisture convergence toward the EA subtropical front. The model calculations suggest that the past changes in TP temperatures and EA summer rainfall may be linked, and that projected future increases in TP temperatures may lead to further enhanced summer frontal rainfall in EA region.

Event Sponsor
SOEST - Meteorology, Manoa Campus

More Information
Cherlyn Young, 956-8775, metdept@hawaii.edu, http://www.soest.hawaii.edu/MET/