For years, the fight against climate change has been symbolized by one number: 1.5. <\/p>\n
Ever since countries agreed in 2015 to an ambition of restricting global warming to 1.5 degrees Celsius above pre-industrial levels, the number has become synonymous with staving off catastrophic climate change. <\/p>\n
But what if the battle to keep global warming from overshooting this limit has already been lost? <\/p>\n
Some prominent scientists argue it has and it\u2019s irresponsible not to sugarcoat the truth. For others, that view is not only wrong, but even \u201cdangerous.\u201d <\/p>\n
It was the renowned climate scientist James Hansen whose comments fueled the debate. In November, he declared the 1.5 degree-limit \u201cdeader than a doornail,\u201d saying it was a shortcoming of the scientific community \u201cto not make clear to the political leaders what the situation is.\u201d <\/p>\n
The rate of global warming is accelerating, he said at a news conference in November, and the world is certain to blow past 1.5 degrees of warming. \u201cAnybody who understands the physics knows that.\u201d <\/p>\n
Hansen\u2019s words have heft \u2014 he is widely credited as the first scientist <\/strong>to publicly sound the alarm on climate change in the 1980s. But other scientists have pushed back hard. <\/p>\n The response from Friederike Otto, a climate scientist <\/strong>at Imperial College London\u2019s Grantham Institute, was <\/strong>even blunter. \u201cI think that\u2019s a very stupid thing to say,\u201d she told reporters in November. \u201cAt the moment, (1.5 degrees) is within reach and to pretend it\u2019s not will just lead to doing nothing even longer.\u201d <\/p>\n Disagreements over climate science are not uncommon \u2014 our planet is a highly complex system, and the nature of reaching consensus typically starts with scientists who disagree. <\/strong> <\/p>\n But as global warming fuels extreme weather \u2014 like heat waves, cyclones and even fierce winter storms, such as those that have torn through parts of the United States \u2014\u00a0the debate over the future of 1.5 is getting unusually heated. <\/p>\n As many parts of the US and Europe deal with <\/strong>an Arctic blast of brutally cold air, it can be hard to recall just how hot 2023 was. <\/strong>Last year saw unprecedented global temperatures, with heat records around the world tumbling. <\/p>\n El Ni\u00f1o \u2014 a natural climate phenomenon that tends to boost the planet\u2019s average temperature \u2014 collided with the long-term trend of global warming, making 2023 the hottest year on record. The year came <\/strong>within a whisker of breaching 1.5 degrees, according to data from the Copernicus Climate Change Service. <\/p>\n While scientists are most concerned about long-term warming over many years, not just one, 2023\u2019s record heat was a stark warning sign. If the world breaches 1.5 degrees over the long term, scientists say the impacts of climate change will start to exceed the ability of humans and ecosystems to adapt. <\/p>\n But every fraction of a degree matters, and climate chaos is already emerging. <\/p>\n Over just a few years, the world has warmed from 1 degree Celsius above pre-industrial levels to around <\/strong>1.2 degrees today \u2014 fractions of a degree that have translated to record breaking extreme weather. <\/p>\n He predicts that by May, the planet will have experienced a 12-month period with an average temperature 1.6 to 1.7 degrees higher than pre-industrial levels. <\/p>\n \u201cFor all practical purposes we are only going to be looking at 1.5 degrees in the rearview mirror,\u201d he said. <\/p>\n At the center of Hansen\u2019s argument is his much-debated assertion that the planet is warming much faster than predicted. <\/p>\n He points to the imbalance between the energy coming in from the sun and what leaves through heat radiating into space. This imbalance has <\/strong>doubled, meaning global warming is escalating, he argued in a November paper he co-authored with more than a dozen other scientists. <\/strong> <\/p>\n The paper\u2019s scientists attribute this mainly to successful global efforts to tackle shipping pollution. <\/p>\n Ships burn fossil fuels that produce carbon emissions, which have a significant impact on global warming. But ships\u2019 exhaust fumes also contain sulfur dioxide. In what may seem a strange twist, the pollutant \u2013 which is highly hazardous for human health \u2013 has a global cooling impact, as the particles reflect sunlight away from the Earth. <\/p>\n Hansen\u2019s research predicts the world will breach the long-term <\/strong>1.5-degree benchmark this decade, and 2 degrees before 2050. That would mean the world has failed to deliver on the central goal in the Paris Agreement on climate change, under which countries pledged to limit warming to well below 2 degrees. <\/p>\n Bill McGuire, emeritus professor of Earth sciences at University College London, shares Hansen\u2019s concerns about the pace of change. <\/strong> <\/p>\n But for many other scientists, there simply isn\u2019t the evidence to say global warming <\/strong>is speeding up. At least not yet. <\/p>\n Last year\u2019s unprecedented heat was boosted by El Ni\u00f1o, Mann said, and \u201cdoes not constitute a change in the trend line.\u201d <\/p>\n The rate of global warming did accelerate after the 1970s as clean air laws reduced air pollution, but since then, \u201cthe planet has warmed at a roughly constant rate,\u201d he said. The reality is bad enough, he added. \ufeff\u201cThere is no need to exaggerate.\u201d <\/p>\n Samantha Burgess, deputy director of Copernicus, said there have been recent climate events that scientists are struggling to understand, including 2023\u2019s record-shattering ocean temperatures. <\/p>\n But in terms of Hansen\u2019s warning about the significant impacts on global warming of cleaning up shipping pollution, \u201cwe don\u2019t see the signal,\u201d she said. <\/p>\n Few scientists will dispute that the world faces a daunting path to limit warming to 1.5 degrees. Even with current climate policies, the planet is on course for nearly 3 degrees of warming. <\/p>\n In some ways, the split between them is, at its heart, a debate about the value of having the 1.5 degree limit in the first place. <\/p>\n If we say 1.5 degrees is dead, Otto said, \u201cthat means, for a lot of people, probably the conclusion is, \u2018OK, then it\u2019s not even worth trying.\u2019\u201d <\/p>\n Smith said it risks playing into a \u201cfatalistic narrative that is actually quite dangerous,\u201d potentially persuading leaders to think \u201cwe\u2019ve failed, anything goes now.\u201d <\/p>\n Mann said it was \u201cirresponsible\u201d to claim 1.5 degrees is dead when the world can avoid crossing the threshold by making substantial and immediate reductions in carbon pollution. <\/p>\n McGuire takes the opposite view. There is no feasible way the world can meet this limit which would require nearly halving emissions by 2030, he said. \u201cTo suggest otherwise is duplicitous and presents a false picture of where we are.\u201d\u200b Framing 1.5 as a \u201ctarget\u201d to be reached, rather than a limit to stay under, has given the illusion we have more <\/strong>time than we do to tackle the crisis, he said, and has allowed countries and companies keep burning fossil fuels. <\/p>\n But one major concern <\/strong>is that if politicians abandon 1.5 degrees, they won\u2019t strive to restrict global warming to 1.6 or 1.7 degrees, but will instead focus on 2 degrees \u2014 the upper <\/strong>limit countries committed to in the 2015 Paris Agreement. <\/p>\n \u201cThat is a huge danger, and that would really be catastrophic,\u201d said Otto. <\/p>\n Between 1.5 and 2 degrees lies disaster: The risk of triggering a slew of climate tipping points, including ice sheet melting and mass coral reef death, and the lives and livelihoods of millions of people. <\/p>\n We will reach 1.5 degrees as a global average temperature, probably next year, Otto said. \u201cWhether we stay there, or how much we go above that, really is still a political question and it is in our gift <\/strong>to change that.\u201d <\/p>\n\n For years, the fight against climate change has been symbolized by one number: 1.5. Ever since countries agreed in 2015 to an ambition of restricting global warming to 1.5 degrees Celsius above pre-industrial levels, the number has become synonymous with staving off catastrophic climate change. But what if the battle to keep global warming from <\/p>\n","protected":false},"author":0,"featured_media":14231,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[],"class_list":{"0":"post-14230","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-world"},"_links":{"self":[{"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/posts\/14230","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/comments?post=14230"}],"version-history":[{"count":0,"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/posts\/14230\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/media\/14231"}],"wp:attachment":[{"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/media?parent=14230"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/categories?post=14230"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/tags?post=14230"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}} Extraordinary heat<\/h2>\n
Is climate change accelerating?<\/h2>\n
Why 1.5 matters<\/h2>\n