State to take another shot at cloud seeding

Even as the IMD has predicted more than average rainfall this monsoon, the state government has called for Expression of Interest (EOI) for cloud seeding operations over catchment areas of reservoirs across the state.

Officials said that cloud seeding would be done in June after studying the precipitation and cloud-aerosol (small particles dispersed in air or gas) interaction. This would ensure there is ample rainfall in the catchment areas, they said.

Taking a cue from the Rs 28-crore failed weather modification exercise of 2015 which was done over relatively drier areas of Marathwada and Aurangabad, this time the officials concerned have taken advice from the Indian Institute of Tropical Meteorology (IITM) and are conducting the experiment all over the state. IITM was of the opinion that cloud seeding has low success rate in dry areas and therefore, it should be done in other regions also.

The experiment will be conducted in the second half of June based on IMD predictions of rainfall during that time and suitability of the clouds for the experiment.

Director of Relief and Rehabilitation (revenue and forest department) has called for EOI from firms that have carried out cloud seeding using rocket technology for any government or semi-government organisations between 2013-2016.

As the shortlisted organisation is supposed to carry out cloud seeding operations using rocket technology, a C-Band Doppler Weather Radar will be installed in Aurangabad to carry out the study. Officials confirmed that request for tender (RFT) documents would be provided to organisations that have been invited to submit tenders for the EOI process. “An evaluation committee comprising representatives from IMD, IITM and government of Maharashtra will evaluate the applications on the basis of capacity, capability and experience of the firms,” said a government official.

IITM scientists said they had suggested experimenting in catchment areas after studying the cloud patterns and other aspects.

Deputy director general, western region of IMD, K.S. Hosalikar said they were not part of the 2015 weather modification team but would provide any scientific and technical help to the government this year. “To review the performance, we need to have a strong set up of calibrated rain guagers across the entire region. There have been numerous limitations to the programme itself due to its dependency on Doppler imaging, depth and time of seeding, meteorological conditions of the vicinity and natural factors. IITM will play a crucial role and we will assist with technical support for the programme,” said Mr Hosalikar

Dr Thara Prabhakaran, chief project director for Cloud Aerosol Interaction and Precipitation Enhancement Experiment at IITM, said that though the IMD had predicted good rains this year, cloud seeding was being undertaken owing to regional unpredictability. “IMD forecasts for the entire nation and one cannot pinpoint the specific regions which will have steady rainfall. Currently, the IITM has undertaken research on complex process of rain formation, cloud-aerosol interaction and precipitation enhancement experiments. The areas will be decided based on research observations,” said Dr Prabhakaran.