{"id":16304,"date":"2021-05-05T08:27:59","date_gmt":"2021-05-04T20:27:59","guid":{"rendered":"https:\/\/www.greenpeace.org\/aotearoa\/?p=16304"},"modified":"2024-07-12T08:28:39","modified_gmt":"2024-07-11T20:28:39","slug":"1-5-degree-global-warming-limit-is-not-impossible-but-without-political-action-it-soon-will-be","status":"publish","type":"post","link":"https:\/\/www.greenpeace.org\/aotearoa\/story\/1-5-degree-global-warming-limit-is-not-impossible-but-without-political-action-it-soon-will-be\/","title":{"rendered":"The 1.5\u2103 global warming limit is not impossible \u2013 but without political action it soon will be"},"content":{"rendered":"\n

Limiting global warming to 1.5\u2103 this century is a central goal of the Paris Agreement. In recent months, climate experts and others<\/a>, including in Australia, have suggested<\/a> the target is now impossible.<\/p>\n\n

Whether Earth can stay within 1.5\u2103 warming involves two distinct questions. First, is it physically, technically and economically feasible, considering the physics of the Earth system and possible rates of societal change? Science indicates the answer is \u201cyes\u201d \u2013 although it will be very difficult and the best opportunities for success lie in the past.<\/p>\n\n

The second question is whether governments will take sufficient action to reduce greenhouse gas emissions. This answer depends on the ambition of governments, and the effectiveness of campaigning by non-government organisations and others.<\/p>\n\n

So scientifically speaking, humanity can still limit global warming to 1.5\u00b0C this century. But political action will determine whether it actually<\/em> does. Conflating the two questions amounts to misplaced punditry, and is dangerous.<\/p>\n\n

1.5\u2103 wasn\u2019t plucked from thin air<\/h2>\n\n

The Paris Agreement<\/a> was adopted by 195 countries in 2015. The inclusion of the 1.5\u2103 warming limit came after a long push by vulnerable, small-island and least developed countries for whom reaching that goal is their best chance for survival<\/a>. The were backed by other climate-vulnerable<\/a> nations and a coalition<\/a> of high-ambition countries.<\/p>\n\n

The 1.5\u2103 limit wasn\u2019t plucked from thin air \u2013 it was informed by the best available science. Between 2013 and 2015, an extensive United Nations review process<\/a> determined that limiting warming to 2\u2103 this century cannot avoid<\/a> dangerous climate change.<\/p>\n\n

Since Paris, the science on 1.5\u2103 has expanded rapidly. An Intergovernmental Panel on Climate Change (IPCC) report<\/a> in 2018 synthesised hundreds of studies and found rapidly escalating risks in global warming between 1.5\u2103 and 2\u2103.<\/p>\n\n

The landmark report also changed the climate risk narrative away from a somewhat unimaginable hothouse world in 2100, to a very real threat within most of our lifetimes \u2013 one which climate action now could help avoid<\/a>.<\/p>\n\n

The message was not lost on a world experiencing ever more climate impacts firsthand<\/a>. It galvanised an unprecedented global youth and activist movement<\/a> demanding action compatible with the 1.5\u2103 limit.<\/p>\n\n

The near-term benefits of stringent emissions reduction are becoming ever clearer. It can significantly reduce near-term warming rates<\/a> and increase the prospects for climate resilient development<\/a>.<\/p>\n\n

A matter of probabilities<\/h2>\n\n

The IPCC looked extensively at emission reductions required to pursue the 1.5\u2103 limit. It found getting on a 1.5\u2103 track is feasible but would require halving global emissions by 2030 compared to 2010 and reaching net-zero emissions by mid-century.<\/p>\n\n

It found no published emission reduction pathways giving the world a likely (more than 66%) chance of limiting peak warming this century to 1.5\u2103. But it identified a range of pathways with about a one-in-two chance of achieving this, with no or limited overshoot.<\/p>\n\n

Having about a one-in-two chance of limiting warming to 1.5\u2103 is not ideal. But these pathways typically have a greater than 90% chance of limiting warming to well below 2\u2103, and so are fully compatible<\/a> with the overall Paris goal.<\/p>\n\n

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Read more: Spot the difference: as world leaders rose to the occasion at the Biden climate summit, Morrison faltered<\/a><\/strong><\/em><\/p>\n\n

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Don\u2019t rely on carbon budgets<\/h2>\n\n

Carbon budgets show the amount of carbon dioxide that can be emitted for a given level of global warming. Some point to carbon budgets to argue the 1.5\u2103 goal is now impossible.<\/p>\n\n

But carbon budget estimates are nuanced, and not a suitable way to conclude a temperature level is no longer possible.<\/p>\n\n

The carbon budget for 1.5\u2103 depends on several factors, including:<\/p>\n\n