Cloud seeding: A technique Delhi may adopt to improve AQI
Amidst the alarming concerns regarding Delhi's rising air pollution, the Delhi government is likely to consider a proposal to practice cloud seeding to improve the city's air quality index (AQI). The decision is yet to be taken as the authorities are awaiting approvals. In the meantime, let's understand what cloud seeding is and how it can help alleviate pollution.
Cloud seeding induces artificial rain over a specific area
Cloud seeding is a weather modification technique that improves the clouds' ability to rain. It involves dispersing substances into the air that can cause the clouds over that area to rain or snow. The most common substances used are dry ice, silver iodide, and potassium iodide. Some may also use liquid propane that transforms into gas. Research shows table salt is just as good.
Other modes include electric charges and infrared laser pulses
Another 'seed' to implant rains in the clouds is to induce electric charges using drones equipped with electric-charge emission instruments and customized sensors. Infrared laser pulses, on the other hand, involve directing electromagnetic radiation into the air. It's invisible to the human eye.
How is cloud seeding done?
Cloud seeding is either done from the ground using generators or with the help of aircraft that fly at low altitudes. Typically, silver iodide is burned from ground-based generators or is released from the aircraft. Once it comes in contact with the clouds that already carry moisture, the silver iodide makes it dispense rain more effectively. The presence of moisture-filled clouds is a must.
Does cloud seeding work? Let's find out
Since 2021, the United Arab Emirates (UAE) has been practicing the electric charge method of sending drones equipped with electric-charge emission instruments into the air. Turns out, this method led to significant rainstorms in the country in July 2021. Various studies, however, reveal that cloud seeding can only produce a little rain or snow than the technique claiming to generate increased precipitation.
How can this technique help Delhi improve its AQI?
If cloud seeding is taken into consideration, it can produce some amount of rainfall that can free the atmosphere from pollutants like soot and sulfate that exist in both gaseous and particulate states. Once these pollutants are taken down by the rain onto the ground, it can improve the city's air quality and reduce the thick blanket of smog.
Let's find out the benefits of cloud seeding
One of the most important benefits of cloud seeding is that it can help mankind regulate weather conditions. Regions that are not blessed with good weather conditions and crave rain or snowfall can hugely benefit from this technique. This makes dry places more livable. Additionally, it also boosts the economy as it makes agriculture and other farming practices more favorable to take place.
It also has some downsides
Cloud seeding is an expensive process as it involves the cost of on-ground generators or aircraft that carry the substance in the air. If not managed well, it could also pose environmental problems. For instance, dry regions that aren't well-positioned to handle water can experience floods on receiving artificial rain. The technique heavily depends on atmospheric conditions and can only be practiced if favorable.
The future of cloud seeding is still debatable
Even after its efficacy in helping many regions around the world experience rain or snowfall, cloud seeding remains a subject of debate. This is because of the unknown impact of long-term exposure to this technique. Experts are yet to be sure about cloud seeding's impact on soil, plants, and animals, and the kind of health issues it can pose.
