Cloud Seeding:
Countries in middle-east and north Africa are racing to develop chemicals to get rain drops out of the cloud.
- Cloud seeding is a type of weather modification that aims to change the amount or type of precipitation that falls from clouds by dispersing substances (such as silver iodide, potassium iodide and dry ice (solid carbon dioxide) and liquid propane) into the air that serve as cloud condensation or ice nuclei.
- It improves a cloud’s ability to produce rain or snow, supplements the rainwater supplyand cleans the atmosphere by introducing tiny ice nuclei into certain types of subfreezing clouds. These nuclei provide a base for snowflakes to form.
- So far, experts haven’t found any harmful effects of cloud seeding with silver iodide on the environment. But Silver iodide can be toxic to aquatic life.
- The concentration of silver in a storm from cloud seeding is far below the accepted limit of 50 micrograms per litre.
- In India, cloud seeding operations were conducted during the years 1983, 1984–87,1993-94 by Tamil Nadu Govt due to severe drought. In the years 2003 and 2004 Karnataka government initiated cloud seeding.