Explanation:

All statements are correct.

• According to a recent report, the Hindu Kush Himalaya is experiencing significantly lower snow persistence this year, raising serious concern over water security for downstream communities.

• Snow persistence is the fraction of time snow is on the ground.

• When this snow melts, it provides water to people and ecosystems.

• In the river basins of the Hindu Kush Himalaya (HKH), snowmelt is the biggest source of water in the streams.

• Snowmelt accounts for around 23% of the total water flow of 12 major river basins originating in the HKH.

• Overall, it contributes 23% of the runoff to the region’s 12 major river basins every year.

Reasons for lower persistence in 2024

• The primary reason for the lower persistence in 2024 was weak western disturbances.

• Western disturbances are low-pressure systems that originate over the Mediterranean Sea, the Caspian, and the Black Seas and bring rain and snow to the HKH region in winter.

• Exacerbated by global warming and prolonged La Nina conditions affecting weather patterns.

Hence option 3rd is correct.