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Showing posts from October, 2020

The Five FAQs - Cyclone

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What is a cyclone? A cyclone is an extreme weather phenomenon caused by disturbances around a low pressure area over water bodies. Winds spiral around the centre of this low pressure area in a snake-like coil and gather speed. These winds rotate counterclockwise in the northern hemisphere and clockwise in the southern hemisphere. What are the conditions in which a cyclone is formed? A warm sea (a temperature in excess of 26 degrees Celsius to a depth of 60 m) with abundant and turbulent transfer of water vapour to the overlying atmosphere by evaporation. Also, atmospheric instability encourages formation of massive vertical cumulus clouds due to convection with condensation of rising air above the ocean surface.   How can one prepare for a cyclone? Keeping mobile phones charged to ensure connectivity, checking verified sources of information for weather updates, keeping valuables and important documents in water-proof containers, along with preparing an emergency kit helps in preparing

Earthquake : The Trouble of Rubble

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Living in a 15 year old house, Mr. Dhawan rarely paid attention to the cracks in the ceiling and loose shelves on the walls. His neighbour told him to repair the damaged walls countless number of times, but Mr. Dhawan, who lived alone, had already adjusted to the broken-ness of his house. On the morning of 26 January 2001, when Mr. Dhawan was leaving his house in Bhuj to attend the Republic Day Celebrations in his society’s park, a massive 7.9 magnitude earthquake struck. Luckily he had reached the park, dropped down and covered his head with his hand and stayed in the open space. While he was safe along with other people, he saw his house tumble down to pieces in front of his eyes. There was nothing left, only rubble.   The sudden tremors, shaking or vibration of the earth’s surface is called an Earthquake. There are natural factors as well as some man made factors. Natural factors like disturbance in the earth’s crust (uppermost layer of the earth) or movement of earth’s plates shows

Getting A Grip On Landslides

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On their way to the Char Dham yatra to Badrinath for the first time, Mr. Verma and his family were enjoying the cloudy weather on their route. Unfortunately, it began to rain heavily when they were halfway to their destination. They continued their journey with caution, but just a few minutes later got stuck in a 2-km-long jam. They could see from their car, with the little visibility the heavy rain permitted, that a massive piece of slope had slipped down and blocked the roadway.  A landslide is an uncontrollable downhill flow of rock, earth, debris; and is caused by heavy rainfall, earthquake etc. Landslides are among the major geological hazards that affect large parts of India about 12.6% of the landmass, excluding snow-covered areas. The Himalayas, the Northeastern hill ranges, the Western Ghats, the Nilgiris, the Eastern Ghats and the Vindhyans are heavily affected by landslides of a bewildering variety and pose chronic problems for the local communities.    Technology-Driven Sol

In Conversation With Lt Gen Syed Ata Hasnain (Retd), Member, NDMA On Landslides

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Recurring landslides in India bring forth the need to tackle the issue with utmost urgency. Aapda Samvaad spoke with Lt Gen Syed Ata Hasnain (Retd), Member, NDMA on the mitigation and management of landslides in India and how the threat of landslides can be reduced with a combined eort from communities and authorities. How prone is India to landslides? India is ecologically challenged by the phenomenon of landslides. According to the Geological Survey of India (GSI), about 12.6% of our land area is prone to landslides which translates to 24 States in India. The common perception is that most of this would be concentrated in the Himalayan belt, and looking at the risk mapping of landslide prone areas, the Himalayas do emerge as the most risk prone area. But, India has a fairly large percentage of area which is prone to landslides, such as in central India, the Vindhyas; the Western Ghats & Nilgiris, the Eastern Ghats and even the Andaman and Nicobar Islands. How can we reduce the ri