Landfall of the Amphan (very severe cyclonic storm) occurred at 1730 hrs Indian Standard Time (IST) on May 20, 2020, near the West Bengal (W.B.) coast of India. High wind speed, storm surge, and torrential rainfall-induced flooding caused devastation in W.B. The present study aims to analyse the impacts of Amphan cyclone on land use/land cover (LULC) such as built-up area, cropland, brick-kiln industries and vegetation cover of nine districts of W.B. namely, Barddhaman, Nadia, North 24 Parganas, South 24 Parganas, Purba Medinipur, Paschim Medinipur, Haora, and Kolkata. Flood extent has been mapped using Sentinel-1A and B interferometric wide swath (IW) ground range detected (GRD) VV polarisation images dated May 22, 2020. The total actual flooded area covers 488 km² of the study area. For the pre-cyclone period, LULC classification and normalised difference vegetation index (NDVI) have been done using Sentinel-2B multispectral instrument (MSI) images dated May 14, 2020. Post-cyclone NDVI has been computed using Sentinel-2B MSI images dated June 3, 2020. Flood-affected cropland covers a large chunk (88.2%) of the total actual flooded area. Mean NDVI values of non-flooded and flooded cropland and vegetation cover have been reduced between May 14, 2020, and June 3, 2020. District, block and pixel-wise changes in pre- and post-cyclone NDVI values have also been analysed. This study helps planners and policy makers to understand the district-wise flooding behavior, severity of damage to cropland and vegetation cover and to plan restriction on high-value land use in flooded low-lying areas.

2020年5月20日，印度标准时间（IST）1730时，在印度西孟加拉邦（WB）海岸附近发生了Amphan（非常严重的气旋风暴）登陆。高风速，风暴潮和洪灾造成的洪灾造成了WB的破坏。本研究旨在分析Amphan旋风对建成区，农田，砖窑等土地利用/土地覆被（LULC）的影响世界银行的9个区的植被覆盖度分别为：巴尔达曼，纳迪亚，北24帕加纳斯，南24帕加纳斯，普尔巴·梅迪尼普尔，帕斯基姆·梅迪尼普尔，豪拉和加尔各答。已使用2020年5月22日的Sentinel-1A和B干涉测距地带（IW）地面探测到的（GRD）VV极化图像绘制了洪水范围。实际总洪水区域覆盖488 km ²研究区域。对于气旋前期，已使用2020年5月14日的Sentinel-2B多光谱仪（MSI）图像完成了LULC分类和归一化植被指数（NDVI）。使用日期为Sentinel-2B的MSI图像计算了旋风后NDVI。 2020年6月3日。受洪水影响的农田占实际洪灾总面积的很大一部分（88.2％）。在2020年5月14日至2020年6月3日之间，未淹没和淹没的农田和植被的平均NDVI值已降低。还分析了旋风前后NDVI值的区域，区块和逐像素变化。这项研究可帮助规划人员和决策者了解区域性洪水行为，对耕地和植被覆盖的破坏严重程度，并规划对低洼地区高价值土地使用的限制。