Dr A. D. Rao received his M. Sc. degree in Applied Mathematics from Andhra University in 1978 and Ph.D. degree from Indian Institute of Technology Delhi in 1982 for his doctoral work on Numerical Storm Surge Prediction in India. Dr Rao joined the faculty of Centre for Atmospheric Sciences at IIT Delhi in 1982. He held the position of Professor from 2002 to 2022. After serving the Institute as a regular faculty for 40 years, he has joined as an Emeritus Professor in July 2022. His research interests are in developing numerical models for ocean state prediction system along the Indian coasts. This includes storm tides and associated coastal inundation, wind waves, coastal ocean processes and internal waves. Dr Rao has made significant contribution to these fields, which is widely recognized. He has published more than 200 research papers in various national and international journals of repute. He is an elected member of the National Academy of Sciences, Allahabad. Dr Rao was visiting research fellow at the University of Reading, UK during 1983-84. He was Visiting Scientist during 1990-91 at the University of Reading, UK and Florida State University, USA during 1997-98. Dr Rao has guided 18 Ph. D. students. He is very actively involved in several consultancy and sponsored research of national importance. He is associate editor for International Journal of Ocean Climate Systems. He has been invited many times as a guest editor of Natural Hazards and Marine Geodesy to bring out special issues on the topics which are relevant to his field. He is also a member in the editorial board of Natural Hazards.

Significant contributions

The main contribution is in the field of physical oceanography in understanding the coastal ocean processes through numerical modelling and observations. These include modelling of strom tides and associated coastal inundation, estuarine circulation, coastal upwelling processes and internal waves in the Bay of Bengal.

Numerical storm surge prediction models have been developed exclusively for the Indian coastal regions associated with tropical cyclones forming in the Bay of Bengal (BoB) and the Arabian Sea (AS). The non-linear interaction of storm surges, tides and wind waves are studied using coupled hydrodynamic and wind wave models. The coastal zones are identified, where the interaction is significant and also quantified which is in turn helpful for the prediction system more accurately during the cyclone period. Another important contribution is computation of coastal inundation due to combined effect of storm surges, tides and wind waves is computed using state-of-the-art model, ADCIRC along the Indian coasts. This is very imperative for the evacuation of local inhabitants whenever a cyclone approaches towards the coast. Recently, a coupled system is developed by considering the hydrodynamic and hydraulic models to incorporate for the first time the cyclone induced precipitation along with upstream river discharge and application of LULC in the computation of coastal inundation. This would enhance accuracy in the prediction of inland inundation caused by any cyclone impinging the Indian coasts. This model is used on real-time basis for computation of total water elevations along the coast as well as coastal inundation. This information is provided on real-time basis basis to India Meteorological Department for their operational use during any cyclone period.

Generation and propagation of Internal waves (IW) along the western part of the BoB and the Andaman Sea are studied using a 3D hydrostatic / non-hydrostatic numerical models. A detailed study is made to identify the pockets of generation sites of Internal Tides (IT) and associated energetics. Recently, an integrated system is developed using MITgcm model(3D), the internal wave model based on Garrett–Munk spectra (2D) and Price–Weller–Pinkel model (1D), the diurnal variability in the vertical density structure is computed in the presence of seasonal pycnocline and sharp density gradients in the main pycnocline. These models could be further used to study the acoustic field and propagation losses temporally as well as spatially. The concept of using the integrated model for simulating the diurnal variability of the ocean environment can become really handy for Navy operations. Since taking observations of temperature and salinity in real-time could be difficult, the integrated model can be used to simulate the temporal and spatial variations with a reasonable degree of accuracy to further understand the acoustic fields The integrated model is now transferred to NPOL and NODPAC for their operational use.

In addition to the above, I worked in the areas of estuarine circulation and coastal upwelling along the Indian coasts. The extent of the landward intrusion of saline water into a river/estuary has a marked effect on the agricultural productivity of adjacent land. The distance of inland propagation may be expected to vary both seasonally and during the spring-neap tidal cycle. Because of its practical relevance, numerical models have been developed to study the circulation, mixing and salinity intrusion into an estuary. The coastal upwelling along the Indian coasts is also studied using 3D models to understand its generation mechanism by atmospheric winds as well as remote forcing.