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arXiv · 2010.06501

Weather Radar in Nepal: Opportunities and Challenges in Mountainous Region

Rocky Talchabhadel·Ganesh R. Ghimire·Sanjib Sharma·Piyush Dahal·Jeeban Panthi·Rupesh Baniya·Jayaram Pudashine·Bhesh Raj Thapa·Shakti PC·Binod Parajuli
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Abstract

Extreme rainfall is one of the major causes of natural hazards (for example flood, landslide, and debris flow) in the central Himalayan region, Nepal. The performance of strategies to manage these risks relies on the accuracy of quantitative rainfall estimates. Rain gauges have traditionally been used to measure the amount of rainfall at a given location. The point measurement often misrepresents the basin estimates, because of limited density and high spatial variability of rainfall fields across the Himalayas. The Department of Hydrology and Meteorology (DHM), Nepal has planned to install a network of three weather radars that cover the entire country. So far, the first weather radar has been installed in 2019 in the western region of the country. Two more radars will be added for the planned radar network in the near future covering the central and eastern regions of the country. Here we introduce the first installed weather radar in Nepal. We highlight both the opportunities and challenges with the radar observation in the mountainous regions. Radar rainfall estimates across the Himalayas are critical to issue severe weather warnings; forecast floods and landslides; and inform decision making in a broad range of sectors, including water and energy, construction, transportation, and agriculture.

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Rocky Talchabhadel, Ganesh R. Ghimire, Sanjib Sharma, Piyush Dahal, Jeeban Panthi, Rupesh Baniya, Jayaram Pudashine, Bhesh Raj Thapa, Shakti PC, Binod Parajuli. 2020-10-11. Weather Radar in Nepal: Opportunities and Challenges in Mountainous Region. https://doi.org/10.1002/wea.3994

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