Cloud Feedbacks



Other MIPs



Google Calendar

Lab Calendar

Site Map


Privacy & Legal Notice

Thanks to Our Sponsors:

PCMDI > WCRP CMIP3 Model Output > Diagnostic Subprojects Printer Friendly Version
<< Back to WCRP CMIP3 Subprojects

Variation of Indian Summer Monsoon Rainfall on Quasi-Biennial Scales and Changes in Its Subseasonal Variability in AR4 scenarios

PI: Ravi S. Nanjundiah
Institution: Indian Institute of Science
Additional Investigators: J Srinivasan, Sulochana Gadgil
We propose the analyse Quasi-biennial variability of ISMR and its linkages to soil moisture and the variability in the Indian and Pacific Oceans. We propose to investigate whether there will be a change in the character of these events i.e. whether these linkages will strengthen or weaken in AR4 scenarios and the possible cause of these changes. Specifically we would like to study the impact of increasing heat content in the Pacific and Indian Oceans on the Indian Summer Monsoon and its effect on soil moisture and the consequent feedback processes. We also plan to analyse changes on the sub-seasonal scales under various scenarios. Methods of analysis such as the Continous Wavelet Techniques in Space and Time (CWT-ST) and the Intrinsic Mode Function techniques (IMF) would be used in this study. The study for Quasi-biennial variability will be done by initially studying the occurrence of these events with the control simulations, followed by studies under various scenarios upto 2200.

The data required for quasi-biennial variability study would be:
(monthly averages) precipitation, winds, specific humidity and temperature at various levels, soil moisture, fluxes at the surface and at the top of the atmosphere and SST. For studies on the subseasonal variability we would require daily averaged data. Initially (due to much larger data requirements) we will limit to studying these subseasonal scale variations to the first 10 years and the last 10 years of the simulations. The data for this would (daily averages): precipitation, soil moisture precipitable water, winds, temperature and geopotential height at 850 hPa and 200 hPa.
  • Ravi S. Nanjundiah, V. Vidyunmala, J. Srinivasan, 2005: The impact of increase in CO2 on the simulation of tropical biennial oscillations (TBO) in 12 coupled general circulation models. Atmospheric Science Lett, 6, 183-191, doi:10.1002/asl.115. Abstract. Full Article. Edit.

Add Publication

<< Back to WCRP CMIP3 Subprojects
For questions or comments regarding this website, please contact the Webmaster.
Lawrence Livermore National Laboratory  |  Physical & Life Sciences Directorate