Maharashtra considers artificial rains to tackle deficient monsoon

Subject: Geography

Section: Physical geography

Context:

The State government is considering cloud seeding to tackle deficient rainfall in parts of Maharashtra, hoping that artificial rain could save kharif crops and also address depleted water levels in dams.
Details: The government of India had made it clear that artificial rain making techniques involving cloud seeding cannot be used for bringing rain clouds to rainfall deficit/drought areas.
These techniques can only induce potential pre-existing clouds, already passing over a given place, to produce enhanced quantum of rain.

Artificial rains or Cloud seeding:

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 into the air that serve as cloud condensation or ice nuclei, which alter the microphysical processes within the cloud.
Its effectiveness is debated; some studies have suggested that it is difficult to show clearly that cloud seeding has a very large effect.
The usual objective is to increase precipitation (rain or snow), either for its own sake or to prevent precipitation from occurring in days afterward.

Mechanism:

The most common chemicals used for cloud seeding include silver iodide, potassium iodide and dry ice (solid carbon dioxide).
Liquid propane, which expands into a gas, has also been used.
This can produce ice crystals at higher temperatures than silver iodide.
After promising research, the use of hygroscopic materials, such as table salt, is becoming more popular.
When cloud seeding, increased snowfall takes place when temperatures within the clouds are between −20 and −7 °C.
Introduction of a substance such as silver iodide, which has a crystalline structure similar to that of ice, will induce freezing nucleation.
Electric charges:
- Since 2021, the United Arab Emirates has been using a new technology: drones equipped with a payload of electric-charge emission instruments and customised sensors fly at low altitudes and deliver an electric charge to air molecules.
- This method produced a significant rainstorm in July 2021.
Infrared laser pulses:
- An electronic mechanism was tested in 2010, when infrared laser pulses were directed to the air above Berlin by researchers from the University of Geneva.
- The experimenters posited that the pulses would encourage atmospheric sulfur dioxide and nitrogen dioxide to form particles that would then act as seeds.

Applications of Cloud Seeding:

Creation of Rain: Cloud seeding is the best way to consider improving rainfall quantity in case of inadequate rainfall . Arid areas usually have conditions that may be harsh in terms of food security and a conducive environment for living.
- Cloud seeding can bring rain, which makes the natural environment flourish and becomes more habitable.
Boosting of the Economy: Agricultural production is important to the local economies of many regions around the world. Rain is important in achieving a proper harvest.
Weather Regulation: Cloud seeding provides an avenue for controlling prevailing weather conditions in different areas.
Geographically oriented: Cloud seeding is primarily done to create certain conditions in specific areas, also termed as microclimates. Places like airports, for instance, often use cloud seeding to create a stable condition for their runway. This is to ensure that planes are not restricted from taking off or landing.

Concerns:

Some chemicals are potentially harmful to the natural environment and the plants which depend on the contaminated rain to produce food.
Cloud seeding is a very expensive process.
Cloud seeding could have many dire consequences to the environment if not well regulated.
- Dry areas are not usually well-positioned to handle certain weather conditions, and thus, may become easily flooded and cause more harm to the already struggling environment.
For cloud seeding to be successful, certain uncontrollable conditions have to be met. for example:
- Clouds have to be present, not just any cloud but clouds capable of producing rain.
- The atmospheric conditions must also suit the process as certain conditions could lead to an unwarranted result like the rain falling in a different location or not falling at all.