{"id":42045,"date":"2025-04-25T21:08:10","date_gmt":"2025-04-25T15:38:10","guid":{"rendered":"https:\/\/www.nextias.com\/ca\/?p=42045"},"modified":"2025-04-25T21:08:22","modified_gmt":"2025-04-25T15:38:22","slug":"fourth-global-bleaching-event","status":"publish","type":"post","link":"https:\/\/www.nextias.com\/ca\/current-affairs\/25-04-2025\/fourth-global-bleaching-event","title":{"rendered":"Fourth Global Bleaching Event"},"content":{"rendered":"\n<p><strong>Syllabus: GS3\/ Biodiversity and Conservation<\/strong><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Context<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>The US National Oceanic and Atmospheric Administration in partnership with the International Coral Reef Initiative,<\/strong> confirmed that the world is witnessing its <strong>fourth global bleaching event.<\/strong><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>About<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The <strong>bleaching-level heat stress has impacted 83.7%<\/strong> of the planet\u2019s coral reef area and mass <strong>coral bleaching <\/strong>has been recorded in at least <strong>83 countries and territories.\u00a0<\/strong>\n<ul class=\"wp-block-list\">\n<li>The ongoing global coral bleaching event is the <strong>biggest to date.\u00a0<\/strong><\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Previous Bleaching:\u00a0<\/strong>\n<ul class=\"wp-block-list\">\n<li><strong>The 1st and 2nd global coral bleaching events <\/strong>occurred in 1998 and 2010, respectively.\u00a0<\/li>\n\n\n\n<li><strong>The 3rd global coral bleaching event, <\/strong>which occurred from 2014-2017, when 68.2% of the world&#8217;s reef area experienced bleaching-level heat stress.\u00a0<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Future Projections: <\/strong>Climate models predict that by 2040-2050, nearly every coral reef worldwide will face annual bleaching events.<\/li>\n\n\n\n<li><strong>Great Barrier Reef Status: <\/strong>Currently undergoing a sixth mass bleaching event.\n<ul class=\"wp-block-list\">\n<li>Second consecutive bleaching episode after 2016-17.<\/li>\n\n\n\n<li>Caused by prolonged marine heatwaves, especially in Far Northern and Northern regions.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Bleaching History in Australia: <\/strong>Mass coral bleaching events recorded in 1998, 2002, 2016, 2017, 2020, 2022, and 2024.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>What are Corals?<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Corals are <strong>invertebrates <\/strong>that belong to a large group of animals called <strong>Cnidaria<\/strong>.\n<ul class=\"wp-block-list\">\n<li>Corals are formed by <strong>multiple small, soft organisms known as polyps.<\/strong>\u00a0<\/li>\n\n\n\n<li>They secrete a<strong> rocky chalk-like (calcium carbonate) exoskeleton<\/strong> around themselves for protection.\u00a0<\/li>\n\n\n\n<li><strong>Coral reefs<\/strong> are therefore created by <strong>millions of tiny polyps forming large carbonate structures.<\/strong><\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Appearance: <\/strong>Corals range in colour from <strong>red to purple and even blue,<\/strong> but are most commonly shades of<strong> brown and green.<\/strong>\n<ul class=\"wp-block-list\">\n<li>Coral are bright and colorful because of microscopic algae called <strong>zooxanthellae<\/strong>.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>There are three types of coral reefs \u2013<\/strong> fringing reefs, barrier reefs and atolls.\n<ul class=\"wp-block-list\">\n<li>Fringing reefs <strong>form along shorelines, barrier reefs form in open water <\/strong>and <strong>atolls are circular reefs <\/strong>that have formed around <strong>sunken volcanoes.<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Coral Bleaching<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Coral bleaching occurs when<strong> corals expel the colourful algae<\/strong> living in their tissues.\u00a0<\/li>\n\n\n\n<li>Without these helpful algae, the<strong> corals become pale<\/strong> and are vulnerable to <strong>starvation and disease.\u00a0<\/strong><\/li>\n\n\n\n<li>A bleached coral is not dead, but<strong> ocean temperatures need to cool off for any hope of recovery.<\/strong><\/li>\n\n\n\n<li>At least 1<strong>4% of the world\u2019s <\/strong>remaining corals were estimated to have died in the previous two global bleaching events.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>What triggers Coral Bleaching?<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The leading cause of coral bleaching is <strong>climate change.\u00a0<\/strong>\n<ul class=\"wp-block-list\">\n<li>A warming planet means a warming ocean, and a change in water temperature\u2014as little as <strong>2 degrees Fahrenheit<\/strong>\u2014can cause coral to drive out algae.\u00a0<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>Coral also bleaches for other reasons, like <strong>extremely low tides, pollution, or too much sunlight.<\/strong><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Concerns<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Coral bleaching matters because once these<strong> corals die, reefs rarely come back.<\/strong>\u00a0<\/li>\n\n\n\n<li>With few corals surviving, they<strong> struggle to reproduce<\/strong>, and entire reef ecosystems, on which people and wildlife depend, <strong>deteriorate<\/strong>.<\/li>\n\n\n\n<li>This would have dire implications for<strong> ocean health, subsistence fisheries and tourism.\u00a0<\/strong><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Impact of Coral Bleaching<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Wildlife:<\/strong> Thousands of marine animals depend on coral reefs for survival.\n<ul class=\"wp-block-list\">\n<li>Coral reefs <strong>provide shelter, spawning grounds, and protection<\/strong> from predators.\u00a0<\/li>\n\n\n\n<li>They also support organisms at the <strong>base of ocean food chains.\u00a0<\/strong><\/li>\n\n\n\n<li>As reef ecosystems collapse, already <strong>at-risk species may face extinction.<\/strong>\u00a0\u00a0\u00a0<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Humans: <\/strong>Coral reefs are natural barriers that absorb the force of waves and storm surges, keeping <strong>coastal communities safe.\u00a0<\/strong>\n<ul class=\"wp-block-list\">\n<li>Every year, reefs provide about $2.7 trillion in goods and services, according to a 2020 estimate by the Global Coral Reef Monitoring Network.<\/li>\n\n\n\n<li>Bleached coral also <strong>compounds the<\/strong> <strong>overfishing crisis<\/strong> by removing links in the food web and depriving some fish of a place to spawn and develop.<\/li>\n\n\n\n<li><strong>Reef tourism <\/strong>brings in billions of dollars each year and supports thousands of jobs.\u00a0<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Can corals recover from bleaching?<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Corals can recover if conditions improve, but recovery can take years or even a decade, depending on the extent of the damage.<\/li>\n\n\n\n<li>Corals can recover <strong>only if temperatures drop and conditions return to normal.\u00a0<\/strong><\/li>\n\n\n\n<li>When this happens, the <strong>algae returns<\/strong> and the corals gradually regain their health.<\/li>\n<\/ul>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full is-resized\"><img data-dominant-color=\"c8d2ca\" data-has-transparency=\"false\" loading=\"lazy\" decoding=\"async\" width=\"576\" height=\"591\" src=\"https:\/\/wp-images.nextias.com\/cdn-cgi\/image\/format=auto\/ca\/uploads\/2025\/04\/Can-corals-recover-from-bleaching.webp\" alt=\"Can corals recover from bleaching\" class=\"not-transparent wp-image-42046\" style=\"--dominant-color: #c8d2ca; width:346px;height:auto\" srcset=\"https:\/\/wp-images.nextias.com\/cdn-cgi\/image\/format=auto\/ca\/uploads\/2025\/04\/Can-corals-recover-from-bleaching.webp 576w, https:\/\/wp-images.nextias.com\/cdn-cgi\/image\/format=auto\/ca\/uploads\/2025\/04\/Can-corals-recover-from-bleaching-292x300.webp 292w\" sizes=\"auto, (max-width: 576px) 100vw, 576px\" \/><\/figure>\n<\/div>\n\n\n<h2 class=\"wp-block-heading\"><strong>Way Ahead<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Strengthening Marine Protected Areas (MPAs).<\/li>\n\n\n\n<li><strong>Implementing coral restoration techniques<\/strong>, such as coral gardening and breeding resilient coral species, to enhance recovery after bleaching events.<\/li>\n\n\n\n<li>Advocating for global<strong> efforts to reduce greenhouse gas emissions<\/strong> to limit temperature increases and ocean acidification.<\/li>\n\n\n\n<li><strong>Increasing investment in research<\/strong> to better understand coral resilience, bleaching triggers, and recovery processes, alongside developing advanced monitoring technologies.<\/li>\n<\/ul>\n\n\n\n<p><strong>Source: <\/strong><a href=\"https:\/\/www.downtoearth.org.in\/climate-change\/its-official-nearly-84-of-coral-reefs-are-affected-in-the-most-widespread-mass-global-bleaching-event\" rel=\"nofollow noopener\" target=\"_blank\"><strong>DTE<\/strong><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<h3><strong>Context<\/strong><\/h3>\n<li class=\"ms-5\">The US National Oceanic and Atmospheric Administration in partnership with the International Coral Reef Initiative, confirmed that the world is witnessing its fourth global bleaching event.<\/li>\n<p><\/p>\n<h3><strong>About<\/strong><\/h3>\n<li class=\"ms-5\">The bleaching-level heat stress has impacted 83.7% of the planet\u2019s coral reef area and mass coral bleaching has been recorded in at least 83 countries and territories.\u00a0<\/li>\n<li class=\"ms-5\">The ongoing global coral bleaching event is the biggest to date.\u00a0<\/li>\n<p><a href=\"https:\/\/www.nextias.com\/ca\/current-affairs\/25-04-2025\/fourth-global-bleaching-event\" class=\"btn btn-primary btn-sm float-end\">Read More<\/a><\/p>\n","protected":false},"author":15,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[21],"tags":[],"class_list":["post-42045","post","type-post","status-publish","format-standard","hentry","category-current-affairs"],"acf":[],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/posts\/42045","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/users\/15"}],"replies":[{"embeddable":true,"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/comments?post=42045"}],"version-history":[{"count":3,"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/posts\/42045\/revisions"}],"predecessor-version":[{"id":42060,"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/posts\/42045\/revisions\/42060"}],"wp:attachment":[{"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/media?parent=42045"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/categories?post=42045"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/tags?post=42045"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}