The results of a study on winter orographic cloud seeding by Water Analytical Services (WAS) and Weather Modification International (WMI) offer insights into rainfall and water resource availability in the Western Cape for the upcoming winter season.
WAS, a cloud seeding specialist based in Middelburg, Mpumalanga, spent the past two months conducting a study on winter orographic cloud seeding based on requests from potential clients located in the Western Cape.
The study included a simulation which revealed that if cloud seeding was deployed at Theewaterskloof Dam in the Western Cape; precipitation would increase by potentially 40%-50% thereby bolstering the water levels at the dam and its associated reservoir.
“Although the study was initiated by client requests, it is particularly relevant because the Cape experiences winter frontal systems and is a winter rainfall area,” says Franco van der Merwe, MD of WAS.
WAS carried out the study in conjunction with US-based cloud seeding specialist Weather Modification International.
Weather Modification International conducted several simulations in 2017 which provide an indication of the amount of rain that can be precipitated in regions that would typically experience high winter rainfall.
The study was conducted within three areas that experience similar weather patterns to the Western Cape.
Results show immense potential for boosting rainfall in the Western Cape during the 2018 winter season – rainfall that is greatly needed during the current drought.
The study results showed that by deploying the modern application of cloud seeding a hydro-power company in the state of Idaho saw a 16% annual increase in precipitation and a weather modification pilot program in Wyoming saw up to a 17% increase. When examining the results gained for similar projects in the US following a contract for frontal winter orographic cloud seeding, it was determined that the client saw a cost-benefit ratio of 25:1. The achievement of results similar to these by means of cloud seeding would have a significant impact on current water levels in the Cape.
“The Western Cape relies heavily on its winter rainfall, and this year more so than ever,” van der Merwe explains. “These studies support the interest that we are seeing coming out of both the public and private sectors who are excited at the prospect of utilising cloud seeding as a way to increase winter rainfall, thereby alleviating the pressure on water supply and demand that is currently being experienced.”
Cloud seeding is the process of applying natural occurring materials such as dry ice or silver iodide to clouds that enhances the natural process in stimulating precipitation, thereby creating rainfall. Cloud seeding has numerous applications in the agriculture, events and tourism industries as well as for government as a means of securing water security in drought stricken areas.
“The process has been repeatedly proven to be 100% safe for the environment and to have no effect on water quality or the causing of excessive rainfall which some fear may result in flooding,” according to van Der Merwe.
“We have also proven that encouraging rainfall in one area will have zero effect on the natural rainfall in nearby surrounding areas. The fact that we are looking at cloud seeding on a seasonal basis is proof that it is a highly precise process and that it has progressed to the point that it is far more accurate than it was a few years ago.”