Does sea level pressure modulate the dynamic and thermodynamic forcing in the tropical Indian Ocean?
View/ Open
Date
2012Author
Nisha, P.G.
Muraleedharan, P.M.
Keerthi, M.G.
Sathe, P.V.
Ravichandran, M.
Metadata
Show full item recordAbstract
Three areas, the north Indian Ocean (NIO), the equatorial Indian Ocean (EIO) and the south Indian Ocean (SIO), were chosen over the tropical Indian Ocean to investigate the dependency of sea surface temperature (SST), wind speed (WS) and sea level pressure (SLP) on latent heat flux (LHF). The dynamic and thermodynamic behaviour of the tropical Indian Ocean was studied from the trends of the scatter represented by the mean and standard deviation of LHF, WS and humidity gradient, q sub(s) − q sub(a), D sub(q), binned in 1 degree C SST interval plotted against SST. The direct linear relationship of LHF with SST reverses at some point to display an inverse relationship when the atmosphere is coupled with the ocean. The point at which the reversal takes place marks the threshold SST which appears to have an inherent relationship with the SLP, especially when the ocean–atmosphere system is coupled. North of 5 degrees S, the LHF peaks at the threshold SST of 27.5 degrees C and decreases gradually on either side. The resemblance of the SST–LHF curve of SIO and EIO to that of the equatorial Pacific Ocean can be attributed to the fact that both regimes fell under the same pressure band that covers the equatorial Pacific. Shifting of LHF maxima to a lower SST regime as SLP increases is noticed at southern and northern latitudes, while such a regime shift is not noticed at the equator. This phenomenon can be attributed to relatively weaker air–sea coupling and subsequent lower LHF production at the EIO.
Collections
- Scholarly literature [8865]