A new approach within hydrometeorological technique for the estimation of average depth of probable maximum precipitation (PMP) over Nepal

摘要

In Nepal, the most floods occur during monsoon season due to heavy spell of rainfall. These heavy spells occur in association with the formation and movement of depression or cyclonic Storms, which originate in the Bay of Bengal or in the Arabian Sea. Every Year there is evidences of damages in the hydro-structure and local inhabitants due to monsoon catastrophic storm within Nepal. So, for the safety purposes, the estimation of average depth of PMP is utmost important in the country. The paper gives the new approach within the hydro-meteorological technique for the estimation of PMP of specified period within Nepal. The analysis is based on the storm data of the monsoon months. The most effective and extreme rainfall events within Nepal have been considered for the storm analysis. The digital elevation model (DEM) of Nepal, software such as geographical information system (ArcView) and XL solver have been intensively used for the extreme rainfall distribution and Depth Area Duration (DAD) analysis. Further, the moisture maximization factor (MMF) has been worked out for the Nepal. Finally, a combined set of equations has been developed for the estimation Average depth of PMP of specified period.