Hyderabad, Oct 16 (UNI) Taking a cue from Australia and South Africa, scientists in Andhra Pradesh have successfully switched over to 'warm cloud seeding' from 'cold cloud seeding' technique, which is better suited for a tropical country like India to augument rain in the rain-shadow regions of the state.
Talking to newspersons here today, 'Indira Megamadhanamu' Project Director and Coordinator I V Muralikrishna said 'warm cloud seeding' operations involved predominantly ''hygroscopic seeding with two C band radars located at Hyderabad and Anantapur and two aircraft.'' ''Initially, we had problems in inducing rains from warm clouds.
Now we have gained the experience to handle warm clouds,'' former Indian Air Force Pilot S K Dutt said.
Radar Coordinator Wing Commandar G S R Sharma said the cloud seeding carried out for 90 days from July 15 yielded an average rainfall of about 20 mm in more than 530 mandals in the drought-prone districts of Anantapur, Chitoor, Guntur, Kadapa, Karimnagar, Kurnool, Mahboobnagar, Medak, Nalgonda, Nellore, Prakasam and Rangareddy.
Earlier, the state had gone for 'cold cloud seeding' as in the US and used ejectables suited for ''top seeding.'' Similarly, 'S band radar', which was unsuitable for cloud tracking was used and as a result the cloud seed operation did not produce significant results, Prof Muralikrishna said.
Narrating their experiences, Y Ram Reddy and V Narayan Reddy, two farmers from Nalgonda district, said, ''cloud seeding has helped us get rains for more number of days and save our crops cultivated under rain-fed conditions.'' Explaining the operations, for which the state government had allocated Rs 22 crore this year, Prof Muralikrishna said the daily activities included continous observation of clouds suitable for seeding on the radar screen and informing the pilot and district officials about the areas of cloud seeding. Cloud characteristics were monitored throughout the life of the cloud.
There were an average of 21 rainy days in each district during the period of the operation. A record number of 980 rainwater samples in 538 mandals had already been analysed to delineate areas subjected to any pollution, Prof Muralikrishna said.