Research from Profs. Sreenivas’ and Subramanian’s groups on the nocturnal boundary layer have helped in identifying a crucial error in the radiation codes used routinely for atmospheric calculations and, thereby, in solving a nearly ninety-year-old micrometeorological mystery – the origin of the Ramdas layer. The latter entails the formation of a lifted temperature minimum in sharp contrast to typical night-time inversion profiles. The error in existing models was identified when deriving a consistent emissivity scheme for modeling longwave radiative exchanges in the nocturnal boundary layer, which in turn pointed to the role of suspended aerosol particles in generating the elevated minimum and in determining the onset of convection (see Figure). Experiments have conclusively demonstrated the importance of aerosol-induced radiative forcing in shaping near-surface nocturnal temperature profiles. Ongoing efforts in Prof. Sreenivas’ group are attempting to develop models as well as instrumentation towards predicting radiation fog, which would be of direct relevance to airport management.
Prof. Sreenivas’ other interests include double-diffusive and mantle convection, cloud dynamics, improved designs for polyhouse and aeroponics chambers, novel design for heat exchangers, vortex dynamics, and turbulent drag reduction.
Penetrative Convection over the ground, in the stable, nocturnal atmospheric boundary layer (Color represents temperature and arrows for the velocity field vectors).
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