The relationship between intraseasonal and interannual variability during the asian summer monsoon
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
The purpose of this paper is to investigate intraseasonal (30-70 days) and higher frequency (5-30 days) variability and its relationship to interannual variability. Various modelling studies have suggested a link between intraseasonal and interannual variability of the Asian summer monsoon. This relationship has been mainly based upon the similar spatial structures of the dominant EOF patterns of the monsoon circulation on intraseasonal and interannual time scales from simulations with simple models and atmospheric general circulation models. Here we investigate these relationships using 40 years of NCEP/NCAR Reanalysis. Motivation for this study is embodied in the suggestions of Charney and Shukla (1981) that boundary forcing (e.g., sea surface temperature) may predispose the monsoon system towards a dry or wet state, and the result of Palmer (1994), using the Lorenz (1963) model, that the probability of being in one regime of phase space or another is no longer equally probable in the presence of external forcing. To investigate the influence of the boundary forcing, the probability distribution functions (PDFs) of the principal components are given.
- Research Organization:
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Sponsoring Organization:
- USDOE Office of Defense Programs (DP)
- DOE Contract Number:
- W-7405-Eng-48
- OSTI ID:
- 8306
- Report Number(s):
- UCRL-JC-133992; KP1201010; ON: DE00008306
- Resource Relation:
- Conference: Twenty-Third Climate Diagnostics and Prediction Workshop, Miami, FL, October 26-30, 1998
- Country of Publication:
- United States
- Language:
- English
Similar Records
Regional Heat Sources and the Active and Break Phases of Boreal Summer Intraseasonal Variability
The mean evolution and variability of the Asian summer monsoon: comparison of ECMWF and NCEP/NCAR reanalyses