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P. R. Tiwari, S. C. Kar, U. C. Mohanty, S. Kumari, P. sinha, A. Nair, and S. Dey, 'Skill of precipitation prediction with GCMs over north India during winter season', International Journal of Climatology, Vol. 34 (12): 3440-3455, October 2014, doi: 10.1002/joc.3921. ?? 2017 Royal Meteorological Society, published by Wiley Online Library.This study aims to analyse the skill of state-of-the-art of five general circulation models (GCMs) in predicting winter precipitation over northern India. The precipitation in winter season (December, January and February) is very important for Rabi crops in north India, particularly for wheat, as it supplements moisture and maintains low temperature for the development of the crops. The GCM outputs (seasonal mean forecasts issued in November) from various organizations are compared with the observed high-resolution gridded rainfall data obtained from India Meteorological Department (IMD). Prediction skill of such GCMs is examined for the period 1982???2009. The climatology, interannual standard deviation (ISD) and correlation coefficients have been computed for the five GCMs and compared with observation. It is found that the models are able to reproduce the climatology and ISD to varying degrees; however, skill of predictions is too low. Multi-model ensemble (MME) approaches have been employed. It is found that the weighted MME using multiple linear regression technique improves the prediction skill of winter precipitation over northern India. The teleconnection between the sea surface temperature (SST) and winter precipitation revealed that the SST over the Pacific Ocean affects the precipitation over north India in winter season. While this observed feature is represented well by some models with high fidelity, most models are unable to respond to SST variations in the Pacific Ocean in a realistic manner. Lagged correlations between the north India rainfall and SST over the Nino-3.4 region reveal ?? that only two of the five GCMs get the observed simultaneous teleconnection correctly. Furthermore, only one of these two models has the observed phase lag with the strongest correlation as observed

Numerical models are described for the evaluation of the interaction between tide and surge in the Bay of Bengal. The models are used to simulate the combined tidal and surge response on 3 June 1982 along the Orissa coast of India when the landfall of a tropical cyclone led to severe inland flooding. This is one of the few events for which a reliable tide-gauge reading is available and this enables a direct comparison to be made between the model predictions and the observationally determined sea-surface elevation anomaly. The comparison, although only utilizing limited observational data, appears sufficiently good for us to assert that the principal features of the surge response are correctly reproduced. A model simulation is also made of the surge that occurred along the Andhra coast of India during the period 18—20 November 1977 when there was heavy coastal inundation. Although tide-gauge readings are not available for this event, the predicted surge response agrees well with indirect estimates of the maximum sea-surface level and eyewitness accounts of inland flooding. The principal requirement for the operational use of these models is the availability of accurate data on the surface wind field together with a reliable forecast of the track to be followed by the tropical cyclone.