{"id":51175,"date":"2020-02-15T08:54:28","date_gmt":"2020-02-15T13:54:28","guid":{"rendered":"https:\/\/olduvai.ca\/?p=51175"},"modified":"2020-02-15T08:54:30","modified_gmt":"2020-02-15T13:54:30","slug":"guest-post-the-irreversible-emissions-of-a-permafrost-tipping-point","status":"publish","type":"post","link":"https:\/\/olduvai.ca\/?p=51175","title":{"rendered":"Guest post: The irreversible emissions of a permafrost \u2018tipping point\u2019"},"content":{"rendered":"\n<h3 class=\"wp-block-heading\"><a href=\"https:\/\/www.carbonbrief.org\/guest-post-the-irreversible-emissions-of-a-permafrost-tipping-point\">Guest post: The irreversible emissions of a permafrost \u2018tipping point\u2019<\/a><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Across vast swaths of the northern hemisphere\u2019s higher reaches, frozen ground holds billions of tonnes of carbon.&nbsp;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">As global temperatures rise, this \u201cpermafrost\u201d land is at increasing risk of thawing out, potentially releasing its long-held carbon into the atmosphere.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Abrupt permafrost thaw is one of the most frequently discussed \u201ctipping points\u201d that could be crossed in a warming world. However,&nbsp;<a href=\"https:\/\/www.pnas.org\/content\/115\/15\/3882\">research<\/a>&nbsp;suggests that, while this thawing is already underway, it can be slowed with climate change mitigation.Tipping pointsThis article is part of a week-long special series on \u201ctipping points\u201d, where a changing climate could push parts of the Earth system into abrupt or irreversible change<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Yet, what is irreversible is the escape of the carbon that has been \u2013 and is being \u2013 emitted. The carbon released from permafrost goes into the atmosphere and stays there, exacerbating global warming.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In short, what happens in the Arctic does not stay in the Arctic.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Permafrost and the global climate<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Permafrost is ground that has been frozen for at least two consecutive years. Its thickness ranges from less than one metre to more than a kilometre. Typically, it sits beneath an \u201cactive layer\u201d that thaws and refreezes every year.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A warming climate puts this perennially frozen ground at risk. When temperatures rise, permafrost thaws \u2013 it does not melt.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">There is a simple analogy: compare what happens to an ice cube and a frozen chicken when they are taken out of the freezer. At room temperature, the former will have melted, leaving a small pool of water, but the chicken will have thawed, leaving a raw chicken. Eventually, that chicken will start to decompose.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This is exactly what happens to permafrost when temperatures increase. One quarter of the landmass of the northern hemisphere is underlain by permafrost, which acts like Earth\u2019s gigantic freezer and keeps enormous amounts of organic matter frozen.<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/www.carbonbrief.org\/wp-content\/uploads\/2020\/02\/Permafrost_map_all-1024x536.jpg\" alt=\"\" class=\"wp-image-33028\"\/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u2026click on the above link to read the rest of the article\u2026<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Guest post: The irreversible emissions of a permafrost \u2018tipping point\u2019 Across vast swaths of the northern hemisphere\u2019s higher reaches, frozen ground holds billions of tonnes of carbon.&nbsp; As global temperatures rise, this \u201cpermafrost\u201d land is at increasing risk of thawing out, potentially releasing its long-held carbon into the atmosphere. Abrupt permafrost thaw is one of [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[4],"tags":[10797,113,141,29022,23837,5010],"class_list":["post-51175","post","type-post","status-publish","format-standard","hentry","category-environment","tag-carbon-brief","tag-carbon-emissions","tag-climate-change","tag-dr-christina-schadel","tag-permafrost","tag-tipping-point"],"_links":{"self":[{"href":"https:\/\/olduvai.ca\/index.php?rest_route=\/wp\/v2\/posts\/51175","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/olduvai.ca\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/olduvai.ca\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/olduvai.ca\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/olduvai.ca\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=51175"}],"version-history":[{"count":1,"href":"https:\/\/olduvai.ca\/index.php?rest_route=\/wp\/v2\/posts\/51175\/revisions"}],"predecessor-version":[{"id":51176,"href":"https:\/\/olduvai.ca\/index.php?rest_route=\/wp\/v2\/posts\/51175\/revisions\/51176"}],"wp:attachment":[{"href":"https:\/\/olduvai.ca\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=51175"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/olduvai.ca\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=51175"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/olduvai.ca\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=51175"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}