Open Access Digital Repository of Ministry of Earth Sciences, Government of India

Simulation of Indian summer monsoon intraseasonal oscillations in a superparameterized coupled climate model: Need to improve the embedded cloud resolving model

Goswami, BB and Mukhopadhyay, P and Khairoutdinov, M and Goswami, BN (2013) Simulation of Indian summer monsoon intraseasonal oscillations in a superparameterized coupled climate model: Need to improve the embedded cloud resolving model. Climate Dynamics, 41 (5-6). pp. 1497-1507.

Full text not available from this repository. (Request a copy)

Abstract

The characteristic features of Indian summer monsoon (ISM) and monsoon intraseasonal oscillations (MISO) are analyzed in the 25 year simulation by the superparameterized Community Climate System Model (SP-CCSM). The observations indicate the low frequency oscillation with a period of 30-60 day to have the highest power with a dominant northward propagation, while the faster mode of MISO with a period of 10-20 day shows a stationary pattern with no northward propagation. SP-CCSM simulates two dominant quasi-periodic oscillations with periods 15-30 day and 40-70 day indicating a systematic low frequency bias in simulating the observed modes. Further, contrary to the observation, the SP-CCSM 15-30 day mode has a significant northward propagation; while the 40-70 day mode does not show prominent northward propagation. The inability of the SP-CCSM to reproduce the observed modes correctly is shown to be linked with inability of the cloud resolving model (CRM) to reproduce the characteristic heating associated with the barotropic and baroclinic vertical structures of the high-frequency and the low-frequency modes. It appears that the superparameterization in the General Circulation Model (GCM) certainly improves seasonal mean model bias significantly. There is a need to improve the CRM through which the barotropic and baroclinic modes are simulated with proper space and time distribution.

Item Type: Article
Additional Information: Copyrights of this article belongs to Springer.
Uncontrolled Keywords: baroclinic motion; barotropic motion; climate modeling; climate oscillation; computer simulation; convective system; general circulation model; monsoon; parameterization; seasonal variation; summer
Subjects: Meteorology and Climatology
Depositing User: IITM Library
Date Deposited: 18 Jun 2014 11:43
Last Modified: 18 Jun 2014 11:43
URI: http://moeseprints.incois.gov.in/id/eprint/296

Actions (login required)

View Item View Item