{"id":61387,"date":"2025-08-31T12:30:42","date_gmt":"2025-08-31T07:00:42","guid":{"rendered":"https:\/\/vajiramandravi.com\/current-affairs\/?p=61387"},"modified":"2025-09-02T13:45:22","modified_gmt":"2025-09-02T08:15:22","slug":"gangotri-glacier-study-reveals-earlier-snowmelt-trends","status":"publish","type":"post","link":"https:\/\/vajiramandravi.com\/current-affairs\/gangotri-glacier-study-reveals-earlier-snowmelt-trends\/","title":{"rendered":"Gangotri Glacier Study Reveals Earlier Snowmelt Trends"},"content":{"rendered":"<h2><b>Gangotri Glacier Snowmelt Latest News<\/b><\/h2>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">A recent study has reconstructed the long-term discharge flow of the Gangotri Glacier System (GGS), the source of the upper Ganga basin feeding the Bhagirathi River in the central Himalayas.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">With climate change driving faster glacier melt globally, glaciologists are closely examining how changes in Gangotri\u2019s discharge patterns could affect water availability, river flow, and long-term sustainability of the region\u2019s ecosystems and livelihoods.<\/span><\/li>\n<\/ul>\n<h2><b>Composition of the Gangotri Glacier System (GGS)<\/b><\/h2>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The GGS comprises four glaciers \u2014 <\/span><b>Meru<\/b><span style=\"font-weight: 400;\"> (7 km\u00b2), <\/span><b>Raktavaran<\/b><span style=\"font-weight: 400;\"> (30 km\u00b2), <\/span><b>Chaturangi<\/b><span style=\"font-weight: 400;\"> (75 km\u00b2), and the largest, <\/span><b>Gangotri <\/b><span style=\"font-weight: 400;\">(140 km\u00b2).\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Together, the system spans <\/span><b>549 km\u00b2<\/b><span style=\"font-weight: 400;\">, with about <\/span><b>48% glacierised area<\/b><span style=\"font-weight: 400;\">, across elevations from <\/span><b>3,767 m to 7,072 m<\/b><span style=\"font-weight: 400;\">.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The GGS receives precipitation from <\/span><b>western disturbances in winter (October\u2013April)<\/b><span style=\"font-weight: 400;\"> and the <\/span><b>Indian summer monsoon in summer (May\u2013September)<\/b><span style=\"font-weight: 400;\">.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Seasonal rainfall (May\u2013October) averages <\/span><b>260 mm<\/b><span style=\"font-weight: 400;\">, with a mean temperature of <\/span><b>9.4\u00b0C<\/b><span style=\"font-weight: 400;\"> recorded between 2000\u20132003.<\/span><\/li>\n<\/ul>\n<h2><b>New Study on Gangotri Glacier System (GGS)<\/b><\/h2>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The <\/span><b>Hindu Kush Himalaya (HKH)<\/b><span style=\"font-weight: 400;\"> holds vital snow and ice reserves that feed major rivers like the Indus, Ganga, and Brahmaputra, sustaining millions of lives.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">In recent decades, climatic changes have <\/span><b>altered the<\/b> <b>cryosphere and hydrological cycles<\/b><span style=\"font-weight: 400;\">, leading to faster glacial retreat and shifting seasonal discharge patterns.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">While most modelling studies focus on large river catchments, it is difficult to separate the impacts of snowmelt and precipitation there.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Smaller systems like the GGS allow for more precise assessments, making it a preferred choice for hydrologists and climate scientists.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">However, long-term discharge analysis and understanding climatic drivers have remained limited.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">To address this, a new study titled <\/span><i><span style=\"font-weight: 400;\">\u201c<\/span><\/i><b><i>Hydrological Contributions of Snow and Glacier Melt from the Gangotri Glacier System and Their Climatic Controls Since 1980<\/i><\/b><i><span style=\"font-weight: 400;\">\u201d<\/span><\/i><span style=\"font-weight: 400;\"> was conducted.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The study, published in the <\/span><i><span style=\"font-weight: 400;\">Journal of the Indian Society of Remote Sensing<\/span><\/i><span style=\"font-weight: 400;\">, provides deeper insights into GGS\u2019s meltwater contributions and climate influences.<\/span><\/li>\n<\/ul>\n<h2><b>Key Findings of the Study<\/b><\/h2>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The study combined the <\/span><b>Spatial Processes in Hydrology (SPHY) glacio-hydrological model<\/b><span style=\"font-weight: 400;\"> with the <\/span><b>Indian Monsoon Data Assimilation and Analysis (IMDAA) dataset (1980\u20132020)<\/b><span style=\"font-weight: 400;\"> to reconstruct GGS discharge trends.\u00a0<\/span>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"2\"><span style=\"font-weight: 400;\">SPHY model is\u00a0<\/span><b>a hydrological modelling tool<\/b><span style=\"font-weight: 400;\">\u00a0suitable for a wide range of water resource management applications.<\/span><\/li>\n<\/ul>\n<\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">It found that maximum discharge occurs in <\/span><b>summer<\/b><span style=\"font-weight: 400;\">, peaking in <\/span><b>July (129 m\u00b3\/s)<\/b><span style=\"font-weight: 400;\">.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The <\/span><b>mean annual discharge<\/b><span style=\"font-weight: 400;\"> was estimated at <\/span><b>28\u00b11.9 m\u00b3\/s<\/b><span style=\"font-weight: 400;\">, primarily from <\/span><b>snow melt (64%)<\/b><span style=\"font-weight: 400;\">, followed by <\/span><b>glacier melt (21%)<\/b><span style=\"font-weight: 400;\">, <\/span><b>rainfall-runoff (11%)<\/b><span style=\"font-weight: 400;\">, and <\/span><b>base flow (4%)<\/b><span style=\"font-weight: 400;\">.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">A decadal analysis revealed a <\/span><b>shift in discharge peaks from August to July after 1990<\/b><span style=\"font-weight: 400;\">, linked to <\/span><b>reduced winter precipitation<\/b><span style=\"font-weight: 400;\"> and <\/span><b>enhanced early summer melting<\/b><span style=\"font-weight: 400;\">.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The highest volumetric increase (7.8%) occurred between <\/span><b>1991\u20132000 and 2001\u20132010<\/b><span style=\"font-weight: 400;\">.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">While mean annual temperatures rose, there was <\/span><b>no significant trend in precipitation or glacier melt<\/b><span style=\"font-weight: 400;\">.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Snow melt declined due to shrinking snow cover, whereas <\/span><b>rainfall-runoff and base flow increased<\/b><span style=\"font-weight: 400;\">.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The analysis highlighted that <\/span><b>summer precipitation<\/b><span style=\"font-weight: 400;\"> was the main driver of annual discharge, followed by <\/span><b>winter temperature<\/b><span style=\"font-weight: 400;\">.<\/span><\/li>\n<\/ul>\n<h2><b>Implications of the Study on GGS<\/b><\/h2>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The findings highlight <\/span><b>warming-induced hydrological changes<\/b><span style=\"font-weight: 400;\"> in the Gangotri Glacier System (GGS), with increasing rainfall run-off and base flow.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">This aligns with the <\/span><b>25% excess rainfall<\/b><span style=\"font-weight: 400;\"> observed in North India\u2019s summer monsoon (June\u2013August), which has caused frequent floods in Uttarakhand, Jammu, and Himachal Pradesh.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">While such events are often hastily termed \u201ccloudbursts\u201d without scientific evidence, climate change does raise the risk of extreme rainfall.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The study stresses the <\/span><b>need for sustained field monitoring and advanced modelling<\/b><span style=\"font-weight: 400;\"> to improve <\/span><b>water resource management<\/b><span style=\"font-weight: 400;\"> in glacier-fed river basins, ensuring resilience against future hydrological and climatic shifts.<\/span><\/li>\n<\/ul>\n<p><b>Source:<\/b> <a href=\"https:\/\/www.thehindu.com\/sci-tech\/science\/is-the-gangotri-glacier-losing-snow-earlier-than-usual\/article69994253.ece#:~:text=Despite%20the%20warming%2C%20snow%20melt,precipitation%2C%20followed%20by%20winter%20temperature.\" target=\"_blank\" rel=\"nofollow noopener\"><span style=\"font-weight: 400;\">TH<\/span><\/a><span style=\"font-weight: 400;\"> | <\/span><a href=\"https:\/\/www.downtoearth.org.in\/climate-change\/gangotri-glacier-has-lost-10-per-cent-snow-melt-flow-in-four-decades\" target=\"_blank\" rel=\"nofollow noopener\"><span style=\"font-weight: 400;\">DTE<\/span><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>New study on Gangotri Glacier reveals earlier snowmelt and altered discharge patterns, highlighting climate change threats to Himalayan rivers.<\/p>\n","protected":false},"author":18,"featured_media":61578,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[18],"tags":[2418,60,22,59],"class_list":{"0":"post-61387","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-upsc-mains-current-affairs","8":"tag-gangotri-glacier-snowmelt","9":"tag-mains-articles","10":"tag-upsc-current-affairs","11":"tag-upsc-mains-current-affairs","12":"no-featured-image-padding"},"acf":[],"_links":{"self":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts\/61387","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/users\/18"}],"replies":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/comments?post=61387"}],"version-history":[{"count":0,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts\/61387\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/media\/61578"}],"wp:attachment":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/media?parent=61387"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/categories?post=61387"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/tags?post=61387"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}