From UPSC perspective, the following things are important :
Prelims level : Hailstorms
Mains level : NA
To help out horticulturists who face crop damage due to hailstorms, the Himachal Pradesh government will be testing the use of indigenously developed ‘anti-hail guns’.
What are anti-hail guns?
- An anti-hail gun is a machine that generates shock waves to disrupt the growth of hailstones in clouds, according to its makers.
- It comprises a tall, fixed structure somewhat resembling an inverted tower, several metres high, with a long and narrow cone opening towards the sky.
- The gun is “fired” by feeding an explosive mixture of acetylene gas and air into its lower chamber, which releases a shock wave (waves that travel faster than the speed of sound, such as those produced by supersonic aircraft).
- These shock waves supposedly stop water droplets in clouds from turning into hailstones, so that they fall simply as raindrops.
Answer this PYQ in the comment box:
Q.During a thunderstorm, the thunder in the skies is produced by the
- meeting of cumulonimbus clouds in the sky
- lightning that separates the nimbus clouds
- violent upward movement of air and water particles
Select the correct option using the codes given below:
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) None of the above
How do they ‘prevent’ a hailstorm?
- It is this hail formation process that the shock waves from anti-hail guns try to disrupt in a radius of 500 meters, so that the water droplets fall down before they can be lifted by the updrafts.
- The machine is repeatedly fired every few seconds during an approaching thunderstorm.
- However, the effectiveness of anti-hail guns has remained a contentious issue.
How do Hailstorms occur?
- Hail is produced by cumulonimbus clouds, which are generally large and dark and may cause thunder and lightning.
- In such clouds, winds can blow up the water droplets to heights where they freeze into ice.
- The frozen droplets begin to fall but are soon pushed back up by the winds and more droplets freeze onto them, resulting in multiple layers of ice on the hailstones.
- This fall and rise is repeated several times, till the hailstones become too heavy and fall down.