It was noticed that the meso-scale convective circulation of monsoon depression was better represented in the improved analysis.
13 Air-Sea Interface Flux Transfer Processes in the Bay of Bengal 7°N, 10°N and 13°N along 87°E during BOBMEX-Pilot-98
P. Seetaramayya, S. G. Nagar, S.P. Ghanekar and T. Venugopal, Institute of Tropical Meteorology, Pune
Three hourly surface synoptic weather data collected onboard ORV Sagar Kanya (Cruise SK138-C) during BOBMEX Pilot-98, (viz. Sea Surface Temperature (SST), dry bulb and wet-bulb temperatures, wind field, mean sea level pressure (MSLP), total cloud cover and present weather (WW)) for the period 30 October to 5 November, 1998, over the field site at 7° to 13°N along 87°E in the Bay of Bengal were analysed.
The analysis showed that the SST variation from 28.9°C to 29.5°C in general, with an abnormally high value of SST (30.4°C), which was observed at 10°N, 87°E at 1330 IST (08 UTC) on 3 November when the equatorial trough was laid over the station. This high value of SST coincided with a maximum global solar radiation (1064 W m-2) at the same time on that day.
The observed MSLP, wind field, cloud cover and WW showed a semi permanent low pressure trough line lying east-west in direction along 10°N with a maximum cloud zone with rainfall to its south.
The computation of Z/L and Bowen’s ratio showed near- neutral condition on either side of the trough line and unstable conditions in the trough line. The Bowen’s ratio varied from 0.10 to 0.20 in the area of study.
14 A study on the air-sea exchange processes and conserved analysis over the Bay of Bengal during BOBMEX-99
N.V. Sam, U..C. Mohanty, P.V.S. Raju and A.N.V. Satyanarayana, Indian Institute of Technology, New Delhi
The air-sea exchange processes and thermal structure of the marine boundary layer under different convective regimes noticed during BOBMEX-99 were studied. A net oceanic heat loss was found during the active convection period. From the conserved variable analysis, double mixing line structure was noticed confirming the convective activity. Higher values of marine boundary layer height were noticed in the active period and lower values during suppressed convection.
15 Surface heat budget and upper ocean thermal characteristics observed during BOBMEX-99
S.P. Ghanekar, V.S.N. Murty, P. Seetaramayya, V. Ramesh Babu and L.V.G. Rao, Indian Institute of Tropical Meteorology, Pune