Delhi air air pollution: With report air pollution ranges choking the capital, the Delhi authorities on Tuesday pushed for “cloud-seeding” or “synthetic rainfall” as an emergency measure to fight air pollution. Delhi surroundings minister Gopal Rai known as on the Centre to carry an pressing assembly to deal with the scenario and approve the plan to induce synthetic rain over the town.
An analogous proposal was made final November, however it was deserted as a result of unfavourable climate circumstances.
The Delhi authorities had beforehand mentioned that it might cowl your complete value of the experiment. The plan, divided into two phases, was estimated to value ₹1 crore per 100 sq. kilometres. The primary section was anticipated to cowl 300 sq. kilometres at the price of ₹3 crores, with the second section probably masking 1,000 sq. kilometres at the price of ₹10 crores, relying on the success of the preliminary section.
What’s cloud seeding?
Cloud-seeding is a method used to switch climate by releasing silver iodide (AgI) into the ambiance to facilitate the formation of ice crystals, enhancing the cloud’s skill to generate rain. Silver iodide aids within the creation of ice nuclei in clouds, that are crucial for synthetic rain to happen.
Within the strategy of cloud-seeding, chemical compounds like silver iodide, potassium iodide, and dry ice are dispersed into the sky through airplanes and helicopters. These chemical compounds entice water vapour, serving to type rain clouds. Usually, it takes round half-hour for this methodology to supply rainfall.
In response to ScienceDirect, cloud-seeding will be categorised into two varieties:
- Hygroscopic Cloud Seeding: This methodology accelerates the merging of droplets in liquid clouds, creating bigger droplets that finally result in precipitation. Salt particles are typically launched on the cloud’s base.
- Glaciogenic Cloud Seeding: This method induces ice formation in supercooled clouds by dispersing environment friendly ice nuclei like silver iodide or dry ice, which triggers ice nucleation and subsequent precipitation.
The place was it used beforehand?
Cloud-seeding has not but been applied in India as a technique to enhance air high quality. Whereas IIT Kanpur had deliberate to conduct an experiment final 12 months, it has been conducting check runs alongside the Western Ghats since 2018, although the influence on air high quality has not been evaluated.
In December 2023, cloud-seeding was carried out in Lahore, Pakistan, which led to an enchancment within the Air High quality Index (AQI) from 300 (“poor”) to 189 (“reasonable”). Nonetheless, the AQI worsened once more inside two days.
Not a sensible resolution?
Scientists and specialists have labelled the synthetic rain proposal as “impractical,” saying that its effectiveness just isn’t assured.
They mentioned that synthetic rain just isn’t a viable resolution to Delhi’s winter air pollution difficulty and extra analysis is required. “Till we’ve sufficient knowledge or analysis to show its effectiveness, this may very well be a waste of funds. Moreover, the environmental influence of silver iodide must be studied earlier than contemplating its use,” mentioned Mukesh Khare, an air air pollution knowledgeable from IIT Delhi.
Sachin Ghude, a scientist on the Indian Institute of Tropical Meteorology in Pune, which carried out cloud seeding experiments within the Western Ghats from 2015 to 2018, defined that not all clouds are appropriate for seeding. “We want ample clouds, significantly convective clouds. Over the previous week, clouds have been scarce. Our assessments additionally confirmed that even when clouds are current, not all of them will result in rainfall,” he mentioned.
