Sunday, 9 July 2023

Flooding and landslides kill at least twenty two people in northern India.

At least twenty two people have lost their lives in a series of flooding and landslide events across northern India, where this year's monsoon has brought 59% more rainfall so far this year than would be expected at by this date on an average year.

Six people have died in four separate incidents in Himachal Pradesh; three members of the same family died in when their house collapsed after being hit by a landslide. Two other people died in landslides in Kullu and Chamba districts. Also in Shimla, a young girl is reported to have died when a raft of debris caried by floodwaters struck her home; an elderly lady is reportedly still trapped beneath the debris of the building, with rescuers attempting to reach her. The state recorded 14 major landslides and 13 flash floods on Friday 7 and Saturday 8 July 2023. There are also reports of shops being swept away in the resort town of Manali, and of cars being washed away in several districts. Over 700 roads in Himachal Pradesh are currently closed, with flooding and landslips sweeping away many roads connecting remote communities to the outside world, and all schools and colleges will be closed on Monday and Tuesday as a precaution. The city of Solan recorded 135 mm of rain on Sunday 9 July, the highest ever rainfall recorded, breaking a previous record of 105 mm set in 1971. 

The Beas River in Kullu District, Himachal Pradesh, on Sunday 9 July 2023. Press Trust of India.

In Uttarakhand three people are known to have died and three are still missing after a landslide swept their jeep into the swollen Ganga River, while they were undertaking a pilgrimage. Five other people who were in the vehicle have been rescued. In another incident in the same state, a house collapse in Kashipur is reported to have killed two people and injured their granddaughter.

In Jammu and Kashmir two people are reported to have died when a landslide hit the bus they were travelling in in Doda District. Elsewhere in the state, a man was killed when his car was struck by a falling boulder in Ladakh, and two soldiers are reported to have drowned while attempting to cross a river in Poonch District.

Part of the Jammu-Srinagar National Highway in Jammu and Kashmir swept away by a landslide. Press Trust of India.

In Haryana State a man is reported to have drowned in Gurugram District, while another man, reportedly his cousin, is still missing. 

In Uttar Pradesh, a 10-year-old girl is reported to have died when a tree fell onto the shack she was living in in Kaushambi District, while in Muzaffarnagar District a woman and her six-year-old daughter died when the roof of their home collapsed under the weight of water that had pooled there. In the city of Ballia two people died and three more were injured after being struck by lightning in separate incidents. 

Monsoons are tropical sea breezes triggered by heating of the land during the warmer part of the year (summer). Both the land and sea are warmed by the Sun, but the land has a lower ability to absorb heat, radiating it back so that the air above landmasses becomes significantly warmer than that over the sea, causing the air above the land to rise and drawing in water from over the sea; since this has also been warmed it carries a high evaporated water content, and brings with it heavy rainfall. In the tropical dry season, the situation is reversed, as the air over the land cools more rapidly with the seasons, leading to warmer air over the sea, and thus breezes moving from the shore to the sea (where air is rising more rapidly) and a drying of the climate. This situation is particularly intense in South Asia, due to the presence of the Himalayas. High mountain ranges tend to force winds hitting them upwards, which amplifies the South Asian Summer Monsoon, with higher winds leading to more upward air movement, thus drawing in further air from the sea.

Diagrammatic representation of wind and rainfall patterns in a tropical monsoon climate. Geosciences/University of Arizona.

While the monsoon always brings problems to India, this year's monsoon has produced an uneven distribution of rain, with the north of the country receiving 59% more rain than would usually be expected, while in the south, between 23% and 45% less rain than usual has fallen. This year an El NiƱo weather system has been developing over the South Pacific, something which usually tends to supress the Indian monsoon, something which may be happening in the south of the country, but northern India, Pakistan, and Nepal have all been suffering deadly floods, something which may be related to the rising global atmospheric temperatures.

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