After a year of deficient rainfall in 2012,India is predicted to have normal rainfall for the current year. According to S Pai,senior scientist of Indian Meteorological Department (IMD),the country barring some parts is set to experience 98 per cent of the long period average (LPA) rainfall between June to September this year. LPA as defined by the IMD is 890 mm of rainfall,which is the cumulative average of rainfall from 1951-2000.
Rainfall,according to IMD is defined as percentage of the LPA and the terms normal,below normal,above normal and excess are expressed as different percentage of the same. While below normal rainfall is 90-96% of LPA,normal rainfall is 96-104% of LPA,above normal rainfall is 104-110% of LPA.
The long range forecast (LRF) and the consensus statement issued by the South Asia Climate Outlook Forum (SASCOF) in April for South India predicts below normal rainfall in major parts. States of Kerala,Tamil Nadu,parts of Andhra Pradesh and Karnataka have been marked with having below normal rains. These parts of the country had received below normal rainfall also during the monsoon of 2012. Infact some parts of Karnataka,Andhra Pradesh were droughth it due to scanty rainfall.
For Maharashtra,Chhattisgarh Madhya Pradesh and other parts of central India,the 2012 monsoon was below normal,which resulted in drought in parts of Maharashtra. Normal rainfall has been predicted for these parts,for the current monsoon.
Western parts of the states of Gujarat,Rajasthan Harayana,and Jammu Kashmir have been predicted to have below normal rainfall. However,the southern portions of the above states along with the national capital of New Delhi are expected to have normal rainfall.
The prediction for the eastern India is of normal rainfall,with north eastern parts of Assam and Arunachal Pradesh is expected to have above normal rainfall. However,above normal rainfall is expected in northern parts of Bihar,Uttar Pradesh,Uttarakhand also. These states in 2012 has received above normal rains,which had resulted in flash floods killing many.
Pai stated that the model error for the above prediction is around five per cent either ways. Other than local systems a variety of other atmospheric phenomenons have been taken in consideration while preparing the forecasts.
Taking in account the errors induced due to spring time errors,this prediction is with in the scientific parameters . We are keeping a close watch on the oceanic currents,which play a significant part in the monsoon. As of April end,both the positive and negative currents are neutral,which would have no effect on the monsoon, he said. The probable date of arrival of monsoon at the Kerala coast would be predicted later in May.