Bay of Bengal as the Gateway to Indian Monsoon at Intraseasonal Time-scales: A Regional Coupled Model Study
Abstract
It has been widely accepted that air-sea interaction plays an important role in monsoon intraseasonal oscillation (MISO), particularly for convections propagating northward in the Bay of Bengal (BoB). In this study, we performed coupled modeling simulations of MISO with regional atmospheric and oceanic models, specifically Weather Research and Forecasting Model (WRF) and Regional Ocean Modeling System (ROMS). By enabling coupling, compared to the same WRF run with prescribed SST forcing, we found notable improvements; e.g., the precipitation signals become sharper and clearer with increased magnitude of precipitation, and observation-like temporarily southward propagating features are detected along 90 E longitude. We also tried to compare the effect of ocean resolution (0.5 x0.5 vs. 0.125 x0.125 ) on the precipitation simulation. In our results, the finer resolution of ocean model didn t result in notable differences from coarser one while it made the coupled system much more unstable.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 2013
- Accession Number
- ADA598515
Entities
People
- Raghu Murtugudde
Organizations
- University of Maryland