{"id":17066,"date":"2026-08-27T04:31:33","date_gmt":"2026-08-27T04:31:33","guid":{"rendered":"https:\/\/koshalsambada.in\/?p=17066"},"modified":"2026-08-27T04:31:33","modified_gmt":"2026-08-27T04:31:33","slug":"before-and-after-satellite-images-show-how-nepals-green-mountainside-turned-into-debris-field","status":"publish","type":"post","link":"https:\/\/koshalsambada.in\/?p=17066","title":{"rendered":"Before and after: Satellite images show how Nepal\u2019s green mountainside turned into debris field"},"content":{"rendered":"<p><br \/>\n<\/p>\n<div>\n<div class=\"e9jwa\">\n<div class=\"vdo_embedd\">\n<div class=\"GfdvZ\">\n<section class=\"_bIDB  clearfix id-r-component leadmedia undefined undefined  E9tg9 \" style=\"top:0px\">\n<div class=\"_bIDB\" data-ua-type=\"1\" onclick=\"stpPgtnAndPrvntDefault(event)\">\n<div class=\"ypVvZ\">\n<div class=\"WGttI\"><img src=\"https:\/\/static.toiimg.com\/thumb\/msid-133555113,imgsize-729218,width-400,height-225,resizemode-4\/floods.jpg\" alt=\"Before and after: Satellite images show how Nepal\u2019s green mountainside turned into debris field\" title=\"A combination of satellite images shows the valleys near the Nepal-China border on August 23, 2026, before the devastating floods and on August 26, 2026, after the disaster. (Photo: Reuters)\" decoding=\"async\" fetchpriority=\"high\"\/><\/div>\n<\/div>\n<\/div>\n<div class=\"Ta7d_ img_cptn\"><span title=\"A combination of satellite images shows the valleys near the Nepal-China border on August 23, 2026, before the devastating floods and on August 26, 2026, after the disaster. (Photo: Reuters)\">A combination of satellite images shows the valleys near the Nepal-China border on August 23, 2026, before the devastating floods and on August 26, 2026, after the disaster. (Photo: Reuters)<\/span><\/div>\n<\/section>\n<\/div><\/div>\n<\/div>\n<p>Satellite images taken before and after the deadly flash flood near Nepal\u2019s border with Tibet reveal a striking change in the landscape: stretches of green mountainside visible before the disaster are now covered by a broad expanse of brown debris and sediment.<span class=\"id-r-component br\" data-pos=\"2\"\/>The Planet Labs imagery has provided early clues to how the disaster may have started. Experts examining the pictures believe that the lower section of a glacier broke away high in the mountains and plunged hundreds of metres into the valley below, likely carrying or entraining rock and sediment as it fell.<span class=\"id-r-component br\" data-pos=\"4\"\/>Early reports raised an earthquake as a possible trigger, but the US Geological Survey later said the recorded seismic activity came from the collapse itself rather than a separate earthquake, according to news agency Reuters.<span class=\"id-r-component br\" data-pos=\"8\"\/><\/p>\n<p><h3>Satellite pictures point to the starting point<\/h3>\n<\/p>\n<p><span class=\"id-r-component br\" data-pos=\"10\"\/>Sikkim University academic Vikram Gupta, an engineering geology specialist, said the satellite evidence indicated that the collapse began at the glacier\u2019s lower end.<span class=\"id-r-component br\" data-pos=\"12\"\/>&#8220;It\u2019s confirmed that a substantial portion of that glacier snout collapsed to initiate the event &#8211; probably including or entraining a fair amount of rock and sediment,&#8221; Gupta said.<span class=\"id-r-component br\" data-pos=\"14\"\/>Dan Shugar, an earth scientist and associate professor at the University of Calgary, also traced the apparent origin of the disaster to a glacier high above the valley.<span class=\"id-r-component br\" data-pos=\"17\"\/>&#8220;What I can see in this morning&#8217;s satellite imagery from Planet Labs, the lower part of a glacier broke off at about 5,200 metres and crashed onto the valley floor about 1,200 metres below,&#8221; Shugar said.<span class=\"id-r-component br\" data-pos=\"19\"\/>The resulting ice-rock avalanche sent a destructive surge downstream, eventually carrying water, sediment and boulders through the river systems below.<span class=\"id-r-component br\" data-pos=\"21\"\/>A Planet Labs pair taken a day apart captures the border valleys on August 25 and August 26, effectively bracketing the disaster. <!-- -->Other comparisons track the transformation of Manakamana and Khadga Bhanjyang between August 23 and August 26.<span class=\"id-r-component br\" data-pos=\"25\"\/><\/p>\n<div data-pos=\"0\" class=\"id-r-component iIpbx undefined  &#10;        \">\n<div><img decoding=\"async\" alt=\"Screenshot 2026-08-27 091347\" msid=\"133555275\" imgsize=\"1397108\" resizemode=\"4\" width=\"\" title=\"A satellite image shows Manakamana before a flash flood affected the area, Nepal, August 23, 2026. (Photo: Reuters)\" placeholdersrc=\"https:\/\/static.toiimg.com\/photo\/83033472.cms\" offsetvertical=\"0\" placeholdermsid=\"47529300\" type=\"thumb\" class=\"\" src=\"https:\/\/static.toiimg.com\/photo\/imgsize-1397108,msid-133555275\/screenshot-2026-08-27-091347.jpg\" data-api-prerender=\"true\"\/><\/p>\n<p>A satellite image shows Manakamana before a flash flood affected the area, Nepal, August 23, 2026. (Photo: Reuters)<\/p>\n<\/div>\n<\/div>\n<p><span class=\"id-r-component br\" data-pos=\"27\"\/><\/p>\n<div data-pos=\"0\" class=\"id-r-component iIpbx undefined  &#10;        \">\n<div><img decoding=\"async\" alt=\"Screenshot 2026-08-27 091248\" msid=\"133555279\" imgsize=\"1388116\" resizemode=\"4\" width=\"\" title=\"A satellite image shows the valleys near the Nepal-China border on August 26, 2026, after the devastating floods. (Photo: Reuters)\" placeholdersrc=\"https:\/\/static.toiimg.com\/photo\/83033472.cms\" offsetvertical=\"0\" placeholdermsid=\"47529300\" type=\"thumb\" class=\"\" src=\"https:\/\/static.toiimg.com\/photo\/imgsize-1388116,msid-133555279\/screenshot-2026-08-27-091248.jpg\" data-api-prerender=\"true\"\/><\/p>\n<p>A satellite image shows the valleys near the Nepal-China border on August 26, 2026, after the devastating floods. (Photo: Reuters)<\/p>\n<\/div>\n<\/div>\n<p><span class=\"id-r-component br\" data-pos=\"29\"\/>Floodwaters surged through communities along the Bhote Koshi. Rasuwa and nearby districts suffered widespread damage, including to transport links, homes and power infrastructure.<span class=\"id-r-component br\" data-pos=\"31\"\/><\/p>\n<p><h3>Snow cover changed sharply before disaster<\/h3>\n<\/p>\n<p><span class=\"id-r-component br\" data-pos=\"33\"\/>The satellite imagery also showed another significant change in the mountains in the hours before the flood.<span class=\"id-r-component br\" data-pos=\"35\"\/>Comparing satellite images taken roughly a day apart, Shugar noticed a pronounced loss of snow cover.<span class=\"id-r-component br\" data-pos=\"38\"\/>&#8220;Some of the glaciers in the valley were covered in snow yesterday and today they are mostly bare ice. So in other words (and I haven&#8217;t seen any weather station data yet), it was probably warm,&#8221; he said.<span class=\"id-r-component br\" data-pos=\"40\"\/>Whether those warmer conditions contributed directly to the collapse has not yet been established.<span class=\"id-r-component br\" data-pos=\"42\"\/>Nepal\u2019s glaciers have already been undergoing significant long-term changes. A 2023 United Nations assessment found that Nepal\u2019s snow-covered mountains had lost nearly a third of their ice over a little more than three decades because of global warming.<span class=\"id-r-component br\" data-pos=\"45\"\/>It also found that Nepal&#8217;s glaciers melted 65% faster over the preceding decade than during the decade before it.<span class=\"id-r-component br\" data-pos=\"47\"\/><\/p>\n<p><h3>Seismic signal traced to the collapse<\/h3>\n<\/p>\n<p><span class=\"id-r-component br\" data-pos=\"49\"\/>An initial assessment by Nepal\u2019s National Disaster Risk Reduction and Management Authority indicated that an ice-and-rock landslide triggered the debris-laden flood in the Lhende River, around 20 kilometres northeast of the Rasuwagadhi border crossing.<span class=\"id-r-component br\" data-pos=\"51\"\/>Prakash Pokharel, a geologist with the authority who reviewed the Planet Labs images, identified the immediate event as an avalanche involving both ice and rock.<span class=\"id-r-component br\" data-pos=\"54\"\/>&#8220;The flash floods were caused by an ice-rock avalanche on the Nepali side,&#8221; Pokharel said.<span class=\"id-r-component br\" data-pos=\"56\"\/>The USGS assessment provided further clarity on the early earthquake theory. What had initially been identified as a magnitude 4.4 earthquake was subsequently determined to be seismic activity produced by the collapse of glacial rock and ice and the movement of debris, rather than a separate quake preceding the disaster.<span class=\"id-r-component br\" data-pos=\"58\"\/>Shugar said construction activity could also be a factor. On the broader question of global warming, he said &#8220;whether climate change played a role is something we will no doubt be looking into in the near future&#8221;.<span class=\"id-r-component br\" data-pos=\"61\"\/><\/p>\n<p><h3>Search for hundreds still missing<\/h3>\n<\/p>\n<p><span class=\"id-r-component br\" data-pos=\"63\"\/>Search teams have struggled to reach parts of the disaster zone, where poor weather and communications failures have complicated efforts to locate survivors and assess the damage. Rescue helicopters were also unable to land in Syapru Besi and Timure as conditions and disrupted access hampered operations.<span class=\"id-r-component br\" data-pos=\"65\"\/>Rasuwa, a mountainous district of roughly 50,000 people, is also home to several hydropower projects in areas hit hardest by the disaster.<span class=\"id-r-component br\" data-pos=\"68\"\/>By late Wednesday, police in Nepal had recovered 157 bodies. More than 400 tourists were still unaccounted for in Nepal, with tourism officials saying around 340 were foreigners.<span class=\"id-r-component br\" data-pos=\"70\"\/>Many of those caught in the disaster were travelling through the region on pilgrimages to Kailash Mansarovar.<span class=\"id-r-component br\" data-pos=\"72\"\/>Across the border in Tibet, Chinese state media reported three deaths and 265 people missing in Gyirong, while cautioning that the toll was still being verified. <!-- -->The mudslide also severed road, communications and power connections in the border area.<span class=\"id-r-component br\" data-pos=\"76\"\/><\/p>\n<p><h3>Surge sent water levels soaring<\/h3>\n<\/p>\n<p><span class=\"id-r-component br\" data-pos=\"79\"\/>According to the International Centre for Integrated Mountain Development, floodwaters swept sediment and boulders into both the Bhote Koshi and Trishuli river systems as the surge travelled downstream.<span class=\"id-r-component br\" data-pos=\"81\"\/>At Galchhi, the river reportedly climbed roughly nine metres \u2014 about 30 feet \u2014 in half an hour.<span class=\"id-r-component br\" data-pos=\"83\"\/><\/p>\n<p><h3>India evacuates thousands, offers Nepal assistance<\/h3>\n<\/p>\n<p><span class=\"id-r-component br\" data-pos=\"85\"\/>Downstream concerns also reached India. Disaster-response units were put on alert in Bihar and Uttar Pradesh as officials watched for the flood surge from Nepal to enter the Gandak river system.<span class=\"id-r-component br\" data-pos=\"88\"\/>An earlier Central Water Commission advisory, issued after a sudden rise in the Trishuli at Furke Khola, about 160 kilometres from India, had raised the possibility of glacial lake outburst flood activity near the Nepal-China border.<span class=\"id-r-component br\" data-pos=\"90\"\/><\/p>\n<div data-pos=\"0\" class=\"id-r-component iIpbx undefined  &#10;        \">\n<div><img decoding=\"async\" alt=\"Screenshot 2026-08-27 091322\" msid=\"133555286\" imgsize=\"1133846\" resizemode=\"4\" width=\"\" title=\"A drove view of mud covered properties following a flash flood at Trishuli in Nuwakot district, Nepal, August 26, 2026. (Photo: Reuters)\" placeholdersrc=\"https:\/\/static.toiimg.com\/photo\/83033472.cms\" offsetvertical=\"0\" placeholdermsid=\"47529300\" type=\"thumb\" class=\"\" src=\"https:\/\/static.toiimg.com\/photo\/imgsize-1133846,msid-133555286\/screenshot-2026-08-27-091322.jpg\" data-api-prerender=\"true\"\/><\/p>\n<p>A drove view of mud covered properties following a flash flood at Trishuli in Nuwakot district, Nepal, August 26, 2026. (Photo: Reuters)<\/p>\n<\/div>\n<\/div>\n<p><span class=\"id-r-component br\" data-pos=\"92\"\/>Districts along the Gandak&#8217;s downstream course in Bihar and Uttar Pradesh were told to maintain heightened surveillance.<span class=\"id-r-component br\" data-pos=\"95\"\/>About 5,000 residents had already been moved to safety from six Bihar districts by Thursday, with preparations covering as many as 10,000 to 12,000 people if further evacuations were required.<span class=\"id-r-component br\" data-pos=\"98\"\/>Prime Minister Narendra Modi conveyed condolences to Nepal Prime Minister Balendra Shah and offered humanitarian assistance, saying Indian teams were working with Nepalese authorities on rescue and relief.<span class=\"id-r-component br\" data-pos=\"100\"\/>The disaster also comes against a backdrop of more frequent and increasingly powerful extreme events across the Hindu Kush Himalayas, including floods, landslides, avalanches and droughts.<span class=\"id-r-component br\" data-pos=\"102\"\/>For now, the satellite record is helping investigators reconstruct how the catastrophe unfolded \u2014 from the apparent collapse of ice and rock high in the mountains to the destructive torrent that swept through valleys, settlements and river systems far downstream.<\/div>\n<p><br \/>\n<br \/><a href=\"https:\/\/timesofindia.indiatimes.com\/world\/south-asia\/before-and-after-satellite-images-show-how-nepals-green-mountainside-turned-into-debris-field\/articleshow\/133553888.cms\" target=\"_blank\" rel=\"noopener\">Source link <\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>A combination of satellite images shows the valleys near the Nepal-China border on August 23, 2026, before the devastating floods and on August 26, 2026, after the disaster. (Photo: Reuters) Satellite images taken before and after the deadly flash flood near Nepal\u2019s border with Tibet reveal a striking change in the landscape: stretches of green [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":17067,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[31],"tags":[],"class_list":["post-17066","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-31"],"magazineBlocksPostFeaturedMedia":{"thumbnail":"https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg","medium":"https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg","medium_large":"https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg","large":"https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg","1536x1536":"https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg","2048x2048":"https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg","blogsy-small":"https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg","blogsy-small-tall":"https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg","blogsy-small-square":"https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg","blogsy-small-masonry":"https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg","blogsy-medium":"https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg","blogsy-medium-masonry":"https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg","blogsy-large":"https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg","blogsy-wide":"https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg"},"magazineBlocksPostAuthor":{"name":"admin","avatar":"https:\/\/secure.gravatar.com\/avatar\/8709732a479614e7a8aa24d3eb1b239f30dc6d90c61464ed495001e7a469d856?s=96&d=mm&r=g"},"magazineBlocksPostCommentsNumber":"0","magazineBlocksPostExcerpt":"A combination of satellite images shows the valleys near the Nepal-China border on August 23, 2026, before the devastating floods and on August 26, 2026, after the disaster. (Photo: Reuters) Satellite images taken before and after the deadly flash flood near Nepal\u2019s border with Tibet reveal a striking change in the landscape: stretches of green [&hellip;]","magazineBlocksPostCategories":["\u0b26\u0b47\u0b36 \u0b2c\u0b3f\u0b26\u0b47\u0b36"],"magazineBlocksPostViewCount":1,"magazineBlocksPostReadTime":6,"magazine_blocks_featured_image_url":{"full":["https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg",400,225,false],"medium":["https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg",300,169,false],"thumbnail":["https:\/\/koshalsambada.in\/wp-content\/uploads\/2026\/08\/floods.jpg",150,84,false]},"magazine_blocks_author":{"display_name":"admin","author_link":"https:\/\/koshalsambada.in\/author\/admin"},"magazine_blocks_comment":0,"magazine_blocks_author_image":"https:\/\/secure.gravatar.com\/avatar\/8709732a479614e7a8aa24d3eb1b239f30dc6d90c61464ed495001e7a469d856?s=96&d=mm&r=g","magazine_blocks_category":"<a href=\"#\" class=\"category-link category-link-31\">\u0b26\u0b47\u0b36 \u0b2c\u0b3f\u0b26\u0b47\u0b36<\/a>","_links":{"self":[{"href":"https:\/\/koshalsambada.in\/index.php?rest_route=\/wp\/v2\/posts\/17066","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/koshalsambada.in\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/koshalsambada.in\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/koshalsambada.in\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/koshalsambada.in\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=17066"}],"version-history":[{"count":0,"href":"https:\/\/koshalsambada.in\/index.php?rest_route=\/wp\/v2\/posts\/17066\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/koshalsambada.in\/index.php?rest_route=\/wp\/v2\/media\/17067"}],"wp:attachment":[{"href":"https:\/\/koshalsambada.in\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=17066"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/koshalsambada.in\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=17066"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/koshalsambada.in\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=17066"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}