Moored observations of the surface meteorology and air-sea fluxes in the Northern Bay of Bengal in 2015

Thumbnail Image
Weller, Robert A.
Farrar, J. Thomas
Seo, Hyodae
Prend, Channing
Sengupta, Debasis
Lekha, J. Sree
Ravichandran, M.
Venkatesan, Ramasamy
Linked Authors
Alternative Title
Date Created
Related Materials
Replaced By
Atmosphere-ocean interaction
Air-sea interaction
Surface fluxes
Time series of surface meteorology and air–sea fluxes from the northern Bay of Bengal are analyzed, quantifying annual and seasonal means, variability, and the potential for surface fluxes to contribute significantly to variability in surface temperature and salinity. Strong signals were associated with solar insolation and its modulation by cloud cover, and, in the 5- to 50-day range, with intraseasonal oscillations (ISOs). The northeast (NE) monsoon (DJF) was typically cloud free, with strong latent heat loss and several moderate wind events, and had the only seasonal mean ocean heat loss. The spring intermonsoon (MAM) was cloud free and had light winds and the strongest ocean heating. Strong ISOs and Tropical Cyclone Komen were seen in the southwest (SW) monsoon (JJA), when 65% of the 2.2-m total rain fell, and oceanic mean heating was small. The fall intermonsoon (SON) initially had moderate convective systems and mean ocean heating, with a transition to drier winds and mean ocean heat loss in the last month. Observed surface freshwater flux applied to a layer of the observed thickness produced drops in salinity with timing and magnitude similar to the initial drops in salinity in the summer monsoon, but did not reproduce the salinity variability of the fall intermonsoon. Observed surface heat flux has the potential to cause the temperature trends of the different seasons, but uncertainty in how shortwave radiation is absorbed in the upper ocean limits quantifying the role of surface forcing in the evolution of mixed layer temperature.
Author Posting. © American Meteorological Society, 2019. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Climate 32(2), (2019): 549-573. doi: 10.1175/JCLI-D-18-0413.1.
Embargo Date
Weller, R. A., Farrar, J. T., Seo, H., Prend, C., Sengupta, D., Lekha, J. S., Ravichandran, M., & Venkatesen, R. (2019). Moored observations of the surface meteorology and air-sea fluxes in the Northern Bay of Bengal in 2015. Journal of Climate, 32(2), 549-573.
Cruise ID
Cruise DOI
Vessel Name