HR: 08:15h
AN: GC51B-02    [Abstracts]
TI: Development of a Statistical Downscaling Model for Projecting Monthly Rainfall over East Asia from a General Circulation Model Output
AU: * Liu, C
EM: liucm@ntu.edu.tw
AF: Global Change Research Center, National Taiwan University, #1, Sec. 4, Roosevelt Rd., Taipei, 106, Taiwan
AU: Paul, S
EM: saha_na@hotmail.com
AF: Global Change Research Center, National Taiwan University, #1, Sec. 4, Roosevelt Rd., Taipei, 106, Taiwan
AU: Chen, J
EM: cjming@mail.nkmu.edu.tw
AF: Institute of Navigation Science and Technology, National Kaohsiung Marine University, No.142, Haijhuan Rd., Nanzih District, Kaohsiung, 81143, Taiwan
AU: Lin, S
EM: florielin@gmail.com
AF: Global Change Research Center, National Taiwan University, #1, Sec. 4, Roosevelt Rd., Taipei, 106, Taiwan
AB: The objective of this paper is to develop a statistical downscaling model based on established links between large scale variables from a General Circulation Model (GCM) and regional rainfall to project climate change in the 21st century over East Asia. An SVD (singular value decomposition)-based regression model is developed to downscale the GCM data. In order to establish the link between monthly regional precipitation and large scale variables (mean sea level pressure, total precipitation, 10m wind speed, 2m temperature), the IS92a scenario data of ECHAM4/OPCY3 and observation data from the Climate Research Unit from 1901-1990 are used. In the 20th century, their connections have remained unchanged over time for all seasons. The continuity of these relationships to the next century is supported by two different techniques. The first technique, a hypothesis proposed here, expects that the similarity in the main SVD modes of predictors in the model and Empirical Orthogonal Functions of predictors throughout the 20th and 21st century will make the models technically acceptable. The second method assumes that the consistency in between the climate change signals of precipitation in 2090s with respect to 1990s derived by the downscaling model and GCM increases the acceptability of future applications. The applied two techniques support the future application of established relationships in all seasons. By the end of the 21st century, annual rainfall over East Asia is projected to increase by up to 20% over northern China and the Indochina peninsula and decrease by 10% over coast of southern China.
DE: 1637 Regional climate change
DE: 1836 Hydrological cycles and budgets (1218, 1655)
DE: 1847 Modeling
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting