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<\/div>AP Photo\/Francois Mori, File\/Alamy<\/p>\n<\/div>\n<\/figcaption><\/figure>\n<\/p>\n
As the COP26<\/sub> climate negotiations were taking place in Glasgow, UK, in November 2021, a new slogan entered the lexicon: \u201ckeep 1.5\u00b0C alive\u201d. The phrase, on the lips of everyone from politicians to climate scientists, aimed to preserve the goal set six years earlier as part of the Paris Agreement at COP21<\/sub>. In hindsight, this ambition was probably already dead, destined to be deployed only as an empty slogan.<\/p>\n New Scientist<\/i> began making this argument in 2022<\/a>, when the public sentiments of experts didn\u2019t reflect their private views or the data we were seeing. Scientists felt trapped, unable to speak out because limiting warming to 1.5\u00b0C above pre-industrial levels still remained possible according to the laws of physics, while being impossible with any realistic acknowledgment of the political, social and economic upheaval required.<\/p>\n In the intervening years, there has been a growing realisation that 1.5\u00b0C is out of reach, but not a frank conversation about what that means. Now, researchers have for the first time explicitly ruled it out, saying 1.6\u00b0C is the best we can hope for<\/a>, while even higher temperatures are the more likely outcome (see \u201cBest-case scenario for climate change is now 1.6\u00b0C of warming\u201d<\/a>).<\/p>\n <\/p>\n Will this finally be enough for policy-makers to sit up and realise that platitudes and slogans aren\u2019t a sufficient form of climate action? Promises to keep any such goal \u201calive\u201d are pointless without doing the only thing that will prevent temperatures rising: reducing the amount of carbon dioxide and other planet-warming greenhouse gases entering the atmosphere to net zero.<\/p>\n Unfortunately, the phrase \u201cnet zero\u201d is losing its true meaning as a description of atmospheric physics, instead being used by many to mean \u201can environmental policy I don\u2019t like\u201d. This is dangerous, as temperature extremes have us trapped in a vicious cycle of emissions<\/a> that only a net-zero energy system can break (see \u201cOur efforts to cope with extreme temperatures are making them worse\u201d<\/a>). If we are to have any hope of limiting warming, we must learn from the mistakes of \u201ckeep 1.5\u00b0C alive\u201d and not let \u201cnet zero\u201d become meaningless.<\/p>\n Topics:<\/p>\n<\/section><\/div>\n