Seven people have died in two landslides in Nepal this week. Six members of the same family died when their house was swept away when a road collapsed onto it in the village of Cherlabang in Rolpa District on Thursday 12 September 2019. They have been identified as Jaya Budha, 38, his wife Muljyoti Budha, 36, and their two daughters, Bewasti, 9, and Karishma, 2, as well as Shiva Kumari Budha, 28, and her son Asal, 4. Shiva Kumari Budha's husband is understood to be working overseas. The incident was caused by the collapse of a section of the Ghartigaun-Thawang Highway above the village. Residents of the village had been raising concerns about the construction of this highway for some time, claiming that contractors had carried out shoddy work in the absence of proper governmental supervision, and it is understood that Shiva Kumari Budha and her son had moved in with Muljyoti Budha's family out of concern that her own home might be vulnerable to such an event.
The approximate location of the 12 September 2019 Cherlasbang landslide. Google Maps.
On Friday 13 September a rockfall on the Siddhartha Highway at Siddhababa in Palpa District, hit two vehicles, killing the driver of one, who has been identified as Kamal Pariyar of Gulmi District. Two people in the other vehicle escaped unhurt.
The scene of a landslide in Palpa District, Nepal, that killed the driver of a car on Friday 13 September 2019. Mukti Neupane/MyRepublica.
The incidents have been blamed on torrential rainfall that has fallen across the area in the last few days. Landslides are common during the monsoon season in Nepal, which lasts from May to September, with the highest rainfall occurring in July. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall.
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.
Follow Sciency Thoughts on Facebook.