{"id":211647,"date":"2022-08-03T13:59:56","date_gmt":"2022-08-03T11:59:56","guid":{"rendered":"https:\/\/climatescience.press\/?p=211647"},"modified":"2022-08-03T13:59:57","modified_gmt":"2022-08-03T11:59:57","slug":"claim-climate-change-potential-to-end-humanity-is-dangerously-underexplored-say-experts","status":"publish","type":"post","link":"https:\/\/climatescience.press\/?p=211647","title":{"rendered":"Claim: Climate Change: Potential to End Humanity is \u2018Dangerously Underexplored\u2019 say Experts"},"content":{"rendered":"\n
\"\"<\/figure>\n\n\n\n

<\/p>\n\n\n\n

[\u201cExperts\u201d ~cr]<\/p>\n\n\n\n

Peer-Reviewed Publication<\/a><\/p>\n\n\n\n

UNIVERSITY OF CAMBRIDGE<\/p>\n\n\n\n

Global heating could become \u201ccatastrophic\u201d for humanity if temperature rises are worse than many predict or cause cascades of events we have yet to consider, or indeed both. The world needs to start preparing for the possibility of a \u201cclimate endgame\u201d.<\/p>\n\n\n\n

This is according to an international team of researchers led by the University of Cambridge, who propose a research agenda for facing up to bad-to-worst-case scenarios. These include outcomes ranging from a loss of 10% of the global population to eventual human extinction.<\/p>\n\n\n\n

In a paper published today in the journal Proceedings of the National Academy of Sciences<\/em>, the researchers call on the Intergovernmental Panel on Climate Change (IPCC) to dedicate a future report to catastrophic climate change to galvanise research and inform the public. <\/p>\n\n\n\n

\u201cThere are plenty of reasons to believe climate change could become catastrophic, even at modest levels of warming,\u201d said lead author Dr Luke Kemp from Cambridge\u2019s Centre for the Study of Existential Risk.<\/p>\n\n\n\n

\u201cClimate change has played a role in every mass extinction event. It has helped fell empires and shaped history. Even the modern world seems adapted to a particular climate niche,\u201d he said.<\/p>\n\n\n\n

\u201cPaths to disaster are not limited to the direct impacts of high temperatures, such as extreme weather events. Knock-on effects such as financial crises, conflict, and new disease outbreaks could trigger other calamities, and impede recovery from potential disasters such as nuclear war.\u201d<\/p>\n\n\n\n

Kemp and colleagues argue that the consequences of 3\u00b0C warming and beyond, and related extreme risks, have been under-examined.<\/p>\n\n\n\n

Modelling done by the team shows areas of extreme heat (an annual average temperature of over 29 \u00b0C), could cover two billion people by 2070. These areas not only some of the most densely populated, but also some of the most politically fragile.<\/p>\n\n\n\n

\u201cAverage annual temperatures of 29 degrees currently affect around 30 million people in the Sahara and Gulf Coast,\u201d said co-author Chi Xu of Nanjing University.<\/p>\n\n\n\n

\u201cBy 2070, these temperatures and the social and political consequences will directly affect two nuclear powers, and seven maximum containment laboratories housing the most dangerous pathogens. There is serious potential for disastrous knock-on effects,\u201d he said.<\/p>\n\n\n\n

Last year\u2019s IPCC report suggested that if atmospheric CO2<\/sub>\u00a0doubles from pre-industrial levels \u2013 something the planet is halfway towards \u2013 then there is a roughly 18% chance temperatures will rise beyond 4.5\u00b0C.<\/p>\n\n\n\n

However, Kemp co-authored a \u201ctext mining\u201d study of IPCC reports, published earlier this year<\/a>, which found that IPCC assessments have shifted away from high-end warming to increasingly focus on lower temperature rises.<\/p>\n\n\n\n

This builds on previous work<\/a> he contributed to showing that extreme temperature scenarios are \u201cunderexplored relative to their likelihood\u201d. \u201cWe know least about the scenarios that matter most,\u201d Kemp said.<\/p>\n\n\n\n

The team behind the PNAS<\/em> paper propose a research agenda that includes what they call the \u201cfour horsemen\u201d of the climate endgame: famine and malnutrition, extreme weather, conflict, and vector-borne diseases.<\/p>\n\n\n\n

Rising temperatures pose a major threat to global food supply, they say, with increasing probabilities of \u201cbreadbasket failures\u201d as the world\u2019s most agriculturally productive areas suffer collective meltdowns.<\/p>\n\n\n\n

Hotter and more extreme weather could also create conditions for new disease outbreaks as habitats for both people and wildlife shift and shrink. <\/p>\n\n\n\n

The authors caution that climate breakdown would likely exacerbate other \u201cinteracting threats\u201d: from rising inequality and misinformation to democratic breakdowns and even new forms of destructive AI weaponry.<\/p>\n\n\n\n

One possible future highlighted in the paper involves \u201cwarm wars\u201d in which technologically enhanced superpowers fight over both dwindling carbon space and giant experiments to deflect sunlight and reduce global temperatures.<\/p>\n\n\n\n

More focus should go on identifying all potential tipping points within \u201cHothouse Earth\u201d say researchers: from methane released by permafrost melts to the loss of forests that act as \u201ccarbon sinks\u201d, and even potential for vanishing cloud cover.<\/p>\n\n\n\n

\u201cThe more we learn about how our planet functions, the greater the reason for concern,\u201d said co-author Prof Johan Rockstr\u00f6m, Director of the Potsdam Institute for Climate Impact Research.<\/p>\n\n\n\n

\u201cWe increasingly understand that our planet is a more sophisticated and fragile organism. We must do the math of disaster in order to avoid it,\u201d he said.<\/p>\n\n\n\n

Co-author Prof Kristie Ebi from the University of Washington said: \u201cWe need an interdisciplinary endeavor to understand how climate change could trigger human mass morbidity and mortality.\u201d<\/p>\n\n\n\n

Added Kemp: \u201cWe know that temperature rise has a \u2018fat tail\u2019, which means a wide range of lower probability but potentially extreme outcomes. Facing a future of accelerating climate change while remaining blind to worst-case scenarios is naive risk-management at best and fatally foolish at worst.\u201d<\/p>\n\n\n\n

\n\n\n\n

JOURNAL<\/h4>\n\n\n\n

Proceedings of the National Academy of Sciences<\/p>\n\n\n\n

DOI<\/h4>\n\n\n\n

10.1073\/pnas.2108146119 <\/a><\/p>\n\n\n\n

ARTICLE TITLE<\/h4>\n\n\n\n

Climate Endgame: Exploring catastrophic climate change scenarios<\/p>\n\n\n\n

ARTICLE PUBLICATION DATE<\/h4>\n\n\n\n

1-Aug-2022<\/p>\n\n\n\n

From EurekAlert!<\/a><\/p>\n\n\n\n

<\/p>\n\n\n\n

<\/p>\n\n\n\n

via Watts Up With That?<\/mark><\/em><\/strong><\/p>\n\n\n\n

August 3, 2022<\/p>\n\n\n\n

\n
Claim: Climate Change: Potential to End Humanity is \u2018Dangerously Underexplored\u2019 say Experts<\/a><\/blockquote>