Evolution and Progression Characteristics of Indian Summer Monsoon
V.S. Prasad (1), Taiichi Hayashi (2)
(1) on leave from National Center for Medium Range Weather Forecasting, Mausam Bhavan, Lodhi Road, New Delhi, India
(2) Disaster Preventive Research Institute, Kyoto University, Gokasho, Uji, Kyoto,Japan
Indian summer monsoon is the principal rainy season for India and thus the commencement and the cessation of this season bears a great significance. The initiation of the cross equatorial flow off the Somalia coast of Africa during May in response to the heating over the South Asian continent marks the beginning of the summer monsoon evolution process over the Arabian sea. The onset of monsoon over the South Kerala coast is manifested as a consequence of significant changes of atmospheric circulation, cloudiness etc and evolves gradually over the Arabian Sea. Long term records of onset over Kerala suggest that the event is more or less regular and its normal onset date of arrival over kerla is 31st May with standard deviation of about eight days. The recent studies with the large scale analyses of the summer monsoon over the Indian region ( Ramesh et al. 1996, Swati et al. 1999, Fatsullo and Webster 2003, Prasad and Hayashi 2004) suggest that it is possible to determine the onset of monsoon objectively by using potential indicators. In this study the onset, progression and withdrawal of the Indian summer monsoon was retrospectively studied using ERA-40 data for the period 1958-2001. In addition , the temporal evolution of OLR fields from NOAA long term OLR data sets to determine the association of cloud cover with the onset of monsoon.
Submittal Information
Name :
Date :
V.S. prasad
27-Jul-04-12:14:02
Organization :
Theme :
DPRI, Kyoto University
Theme 3
Address :
Presentation :
Research Center for Disaster Enivironment, DPRI, Kyoto University, Gokasho, Uji, Kyoto,Japan