New Delhi: Climate scientists have developed a new method to forecast summer monsoon rainfall which they claim is more accurate than the existing prediction model.

Scientists at the Pune-based Indian Institute of Tropical Meteorology (IITM) applied the new model using the data for the past 10 years and were able to get the monsoon figures right for nine years.

“Our model uses six parameters that include mean sea level pressure, temperature and zonal and meridional wind speed,” IITM’s A A Munot, who developed the model along with his colleague Krishna Kumar, told PTI over phone from Pune.

The duo used the data on the mean sea level pressure, temperature, zonal and meridional wind for the 1949-2005 period for their study that was published in the February issue of Journal of Earth System Science.

The model developed using the data for the last 55 years was verified independently for 1949-1960 period and the more recent 1996-2005 decade and its performance was found to improve over the years.

The Heidke score, used to measure the accuracy of the forecast, for the 1949-1960 period was 68% and improved to 90% for 1996-2005 decade, while it clocked 81% for the total period. A perfect forecast has a Heidke score of 100.

“The performance of the model is good and even better for recent years,” Munot said.

Using this prediction model, the all India summer monsoon rain forecast for 2006 was found to be 92 per cent of the normal.