Friday, 13 July 2018

Landslide kills nine in Manipur, India.

Nine people, including several children, have died in a landslide in Tamenglong District in Manipur State, India, on Tuesday 10 July 2018. The incident happened following several days of heavy rain, associated with the Southwest Monsoon, that have caused a series of floods, landslides and other problems across northeast India. Landslides are 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. 

The scene of a landslide in Manipur, India, where nine people died on 10 July 2018. News 18 Assam/Twitter.

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.

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

Much of Southeast Asia has two distinct Monsoon Seasons, with a Northeast Monsoon driven by winds from  the South China Sea that lasts from November to February and a Southwest Monsoon driven by winds from the southern Indian Ocean from March to October. Such a double Monsoon Season is common close to the equator, where the Sun is highest overhead around the equinoxes and lowest on the horizons around the solstices, making the solstices the coolest part of the year and the equinoxes the hottest. However northeast India is largely protected from the Northeast Monsoon by the mountains to its north and east, though these can also add to the severity of flooding in the region, with melting snow in the Himalayas swelling the rivers that flow through these states.

 The winds that drive the Northeast and Southwest Monsoons in Southeast Asia. Mynewshub.

See also...
Follow Sciency Thoughts on Facebook.

No comments:

Post a Comment