{"id":39966,"date":"2024-04-22T01:31:21","date_gmt":"2024-04-21T20:01:21","guid":{"rendered":"https:\/\/vajiramandravi.com\/current-affairs\/?p=39966"},"modified":"2025-10-10T14:30:02","modified_gmt":"2025-10-10T09:00:02","slug":"fourth-mass-coral-reef-bleaching","status":"publish","type":"post","link":"https:\/\/vajiramandravi.com\/current-affairs\/fourth-mass-coral-reef-bleaching\/","title":{"rendered":"Fourth Mass Coral Reef Bleaching"},"content":{"rendered":"<h2>What\u2019s in today\u2019s article?<\/h2>\n<p>\u25cf Why in News?<\/p>\n<p>\u25cf What are Corals and coral reefs?<\/p>\n<p>\u25cf What is the significance of corals?<\/p>\n<p>\u25cf What is Coral bleaching?<\/p>\n<p>\u25cf Fourth global bleaching event<\/p>\n<h2>Why in News?<\/h2>\n<p>As per the US National Oceanic and Atmospheric Administration (NOAA), the fourth global mass coral bleaching event has been triggered by extraordinary ocean temperatures.<\/p>\n<h2>What are Corals and coral reefs?<\/h2>\n<ul>\n<li><strong>Corals<\/strong>\n<ul>\n<li>Corals are like underwater animals that stay in one place on the ocean floor. They have small tentacles to grab food from the water and bring it into their mouths.<\/li>\n<li>Each individual coral animal is known as a <strong>polyp<\/strong> and it lives in groups of hundreds to thousands of genetically identical polyps that form a colony.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Types of corals<\/strong>\n<ul>\n<li>Corals are largely classified as either hard coral or soft coral.<\/li>\n<li>Unlike soft corals, hard corals have stony skeletons made out of limestone that are produced by coral polyps.<\/li>\n<li>When polyps die, their skeletons are left behind and used as foundations for new polyps.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Coral reefs<\/strong>\n<ul>\n<li>It is the hard corals that are the architects of coral reefs \u2014 complex three-dimensional structures built up over thousands of years.<\/li>\n<li>Coral reefs, also referred to as rainforests of the sea, have existed on the Earth for nearly 450 million years.<\/li>\n<li>Australia\u2019s <a href=\"https:\/\/vajiramandravi.com\/current-affairs\/what-is-the-great-barrier-reef\/\" target=\"_blank\" rel=\"noopener noreferrer\" target=\"_blank\">Great Barrier Reef<\/a> is the largest in the world, stretching across 2,028 kilometres.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h2>What is the significance of corals?<\/h2>\n<ul>\n<li><strong>Biodiversity Hotspots<\/strong>\n<ul>\n<li>Coral reefs are like bustling cities underwater, providing homes for a huge variety of marine life. They are like apartments for fish, crabs, and other creatures.<\/li>\n<li>E.g., the Great Barrier Reef contains over 400 coral species, 1,500 fish species, 4,000 mollusc species and six of the world\u2019s seven sea turtle species.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Protection<\/strong>\n<ul>\n<li>Coral reefs can absorb up to 97% of the energy from waves, storms, and floods, which prevents loss of life, property damage, and soil erosion.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Economic Value<\/strong>\n<ul>\n<li>Coral reefs support industries like fishing and tourism, providing livelihoods for many people around the world.<\/li>\n<li>Tourists love to snorkel and dive among vibrant coral reefs.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Medicine and Science<\/strong>\n<ul>\n<li>Corals hold potential for new medicines and scientific discoveries. They have already contributed to treatments for diseases like cancer and arthritis.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Carbon Cycling<\/strong>\n<ul>\n<li>They play a role in the carbon cycle, helping to regulate the Earth&#8217;s climate by absorbing carbon dioxide from the atmosphere.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h2>What is Coral bleaching?<\/h2>\n<figure class=\"image image_resized\"><img decoding=\"async\" src=\"https:\/\/vajiram-prod.s3.ap-south-1.amazonaws.com\/Coral_Bleaching_f6b0c8c892.webp\" alt=\"Coral Bleaching\" \/><\/figure>\n<ul>\n<li><strong>Symbiotic relationship between corals and zooxanthellae<\/strong>\n<ul>\n<li>Most corals contain algae called zooxanthellae \u2014 they are plant-like organisms \u2014 in their tissues.<\/li>\n<li>Corals and zooxanthellae have a symbiotic relationship.\n<ul>\n<li>Corals provide zooxanthellae a safe place to live.<\/li>\n<li>On the other hand, zooxanthellae provide oxygen and organic products of <a href=\"https:\/\/vajiramandravi.com\/upsc-exam\/photosynthesis\/\" target=\"_blank\" rel=\"noopener noreferrer\" target=\"_blank\">photosynthesis<\/a> that help corals to grow and thrive.<\/li>\n<li>Zooxanthellae also give bright and unique colours to corals.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<li><strong>Coral bleaching<\/strong>\n<ul>\n<li>Corals are very sensitive to light and temperature and even a small change in their living conditions can stress them.<\/li>\n<li>When stressed, they expel zooxanthellae and turn entirely white. This is called coral bleaching.<\/li>\n<li>Coral bleaching doesn\u2019t immediately lead to the death of corals. They rather go under more stress and are subject to mortality.<\/li>\n<li>Coral bleaching reduces the reproductivity of corals and makes them more vulnerable to fatal diseases.<\/li>\n<li>If the bleaching is not too severe, corals have been known to recover.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Global mass bleaching of coral reefs<\/strong>\n<ul>\n<li>Global mass bleaching of coral reefs is when significant coral bleaching is confirmed in the Atlantic, Indian and Pacific oceans.<\/li>\n<li>Such events are a relatively new phenomenon.<\/li>\n<\/ul>\n<\/li>\n<li>The first one took place in 1998 in which 20% of the world\u2019s reef areas suffered bleaching-level heat stress.<\/li>\n<li>The next two global bleaching events occurred in 2010 (35% of reefs affected) and between 2014 and 2017 (56% of reefs affected).<\/li>\n<\/ul>\n<h2>Fourth global bleaching event<\/h2>\n<ul>\n<li><strong>About<\/strong>\n<ul>\n<li>NOAA has confirmed that the fourth global bleaching event is currently underway.<\/li>\n<li>Nearly 54 countries, territories and local economies \u2014 from Florida, the US, Saudi Arabia to Fiji \u2014 have confirmed bleaching.<\/li>\n<li>The Great Barrier Reef is witnessing its most severe bleaching event.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Key driver<\/strong>\n<ul>\n<li>The key driver behind the current event is higher ocean temperatures.<\/li>\n<li>However, the situation has been exacerbated by El Ni\u00f1o, a weather pattern which is associated with warmer oceans.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Impact of the event<\/strong>\n<ul>\n<li>As per the IPCC, the world may lose the vast majority of its coral reefs at 1.5 degree Celsius of warming, and virtually all at 2 degree.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<hr \/>\n<h3>Q.1. What are Global mass bleaching events?<\/h3>\n<p>Global mass bleaching events are \u201ccalled\u201d when significant coral bleaching is confirmed in the Atlantic, Indian and Pacific oceans.<\/p>\n<h3>Q.2. What is Zooxanthellae?<\/h3>\n<p>Zooxanthellae are microscopic, golden-brown, unicellular algae that live in the tissues of most reef-building corals and other marine invertebrates, such as jellyfish, nudibranchs, and demosponges.<\/p>\n<p><strong>Source:<\/strong> <a href=\"https:\/\/indianexpress.com\/article\/explained\/explained-climate\/global-mass-coral-bleaching-triggered-9279731\/\" target=\"_blank\" rel=\"nofollow noopener\"><u>Fourth global mass coral bleaching triggered: What are corals and why are they important?<\/u><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Corals are like underwater animals that stay in one place on the ocean floor.<\/p>\n","protected":false},"author":5,"featured_media":39967,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[18],"tags":[],"class_list":{"0":"post-39966","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-upsc-mains-current-affairs","8":"no-featured-image-padding"},"acf":[],"_links":{"self":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts\/39966","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\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/comments?post=39966"}],"version-history":[{"count":0,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts\/39966\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/media\/39967"}],"wp:attachment":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/media?parent=39966"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/categories?post=39966"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/tags?post=39966"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}