Is climate change an 'existential threat' — or just a catastrophic one?
The following texts have been cut and pasted from the referenced source. Lets start with a brief summary about the consequences, here is an excerpt from: https://www.myclimate.org/information/faq/faq-detail/what-are-the-effects-of-climate-change/
Climate change destabilizes the Earth;s temperature equilibrium and has far-reaching effects on human beings and the environment. During the course of global warming, the energy balance and thus the temperature of the earth change, due to the increased concentration of greenhouse gases, which has a significant impact on humans and the environment.
It is not scientifically possible to assign individual weather events to the current climate change, however, it can be statistically proven that global warming will increase the probability of extreme weather events.
The direct consequences of man-made climate change include:
The indirect consequences of climate change, which directly affect us humans and our environment, include:
The need for adaptation in all areas (e.g. agriculture, forestry, energy, infrastructure, tourism, etc.)
The article continues about the concern that climate warming is self accelerating and that there will be point in time, in the near future that will mark an irreversible and accelerated global warming.
And here is an excerpt from:
NEWSDEFEND THE PLANET By Joe McCarthy and Erica Sánchez JUNE 4, 2019 ;
Climate Change Could Undermine Human Civilization by 2050, Report Argues 'Human life on earth may be on the way to extinction, in the most horrible way.' (Full article: https://www.globalcitizen.org/en/content/climate-change-human-civilization/)
Climate change could cause civilization-ending impacts by 2050, according to a;new report;from Australia-based think-tank;Breakthrough National Centre for Climate Restoration.
The report argues that the United Nations;;assessments on climate change, which call for a rapid transformation of society, do not go far enough in conveying the risk that humanity faces. By focusing on the “threat multipliers of climate change,' how it can worsen existing geopolitical conflicts and stresses, the researchers argue that it could set in motion devastating chain reactions in the near future.
By 2050, global warming could go well beyond the limit recommended by the Paris climate agreement, even reaching 3 degrees Celsius higher than pre-industrial levels because of accelerating feedback loops. A major feedback loop is happening in the Arctic. As ice melts from warmer temperatures, darker water appears, which absorbs more sunlight, causing more warming, and more ice melt. Another one is happening in the region;s permafrost, which is releasing methane as it melts. Cycles like these are dramatically accelerating human-caused climate change.
If the world warms by 3 degrees Celsius, then 55% of the global population could face lethal heat waves 20 days each year. Worsening heat waves are already devastating countries as diverse as Pakistan and Japan. Air conditioners, from refrigerators to the window boxes that cool down rooms, are the;biggest single driver of climate change.
Nearly 30% of the world;s land would become arid under these conditions, and food production in agricultural zones would plummet as precipitation patterns shift. Water availability would become scarce for 2 billion people. Extreme storms, including monsoons and hurricanes, will become more common, the report continues.
Critical global ecosystems including the Amazon rainforest, coral reefs, and the Arctic would collapse at this point, the researchers argue. Poor countries that lack the resources to cope with these changes would become 'unviable,' and global migration patterns would reach catastrophic levels.
David Doniger, the senior strategic director of the Natural Resource Defence Council;s climate and clean energy program says: 'There;s no question that the impacts from climate change will be very severe — they're;already being felt. It;s a major threat to the stability of our civilization and our way of life and our economies and the future of our children and grandchildren. We;re going to need to invest in rebuilding our forests, in technologies that suck carbon dioxide out of the air'. He added 'it doesn;t have to be the total end of human civilization, but it;s a super serious threat'.
Ruth DeFries, professor of ecology and sustainable development at Columbia University, agreed with Doniger. She says that climate change is an enormous threat with far-reaching impacts on food, water, cities, health, and nearly every aspect of life. 'But the end of human civilization is far from inevitable if leaders throughout the world address the problem with the seriousness it deserves.'
The authors of the Breakthrough National Centre for Climate Restoration report say that countries need to pursue net-zero emissions as rapidly as possible. The Paris climate agreement calls on countries to avoid warming of more than 2 degrees Celsius, which would require greenhouse gas emissions to stop accumulating in the atmosphere by 2030.
No country in the world is remotely close to achieving this target —;electricity grids and vehicles are currently dependent on fossil fuels. As a result, the researchers argue that an emergency mobilization of resources; akin to World War II' is needed to transform human society.
Another article posted at https://www.vox.com/future-perfect/2019/6/13/18660548/climate-change-human-civilization-existential-risk is also addressing our question: Is climate change an 'existential threat' — or just a catastrophic one?
The article acknowledges the seriousness and the catastrophic impact of climate change. Yet it objects to the claim that it will lead to the extinction of our species.
The Vice story (https://www.vice.com/en/article/597kpd/new-report-suggests-high-likelihood-of-human-civilization-coming-to-an-end-in-2050) summed up the report from the Breakthrough National Centre for Climate Restoration, arguing that the Intergovernmental Panel on Climate Change analysis of the impacts of climate change understates how much harm it;ll do, and that in reality we face;something much worse, with runaway feedback effects amplifying the initial warming until the Earth is 'largely uninhabitable.' It doesn;t actually argue that the world will end in 30 years,;but it suggests we;ll reach the tipping point by then.
The Breakthrough;report — and the media coverage of it — frustrated many climate scientists. In a;detailed response, six researchers argued that the report overstates the risks from climate change, and that subsequent reporting overstated it even further. The fact is that even the most pessimistic reports, evaluated responsibly, don't suggest climate change will end human civilization, much less within our lifetimes.
However the Vice story resonated with people in part because most mainstream research into climate change has focused — prompted by the IPCC — on scenarios with around 2 degrees of warming, less often on (fairly likely) scenarios with 3 or 4 degrees of warming, and infrequently on worst-case scenarios of climate disaster, leaving a lot of questions about those worst-case;scenarios unanswered. How likely are they? How catastrophic would they be? Scientists don;t all agree, and that uncertainty creates room for the most shocking stories to go viral.
The expected effects of climate change, according to organizations like the; IPCC;and the;World Bank, are fairly terrifying. They suggest the planet;s climate will change fast enough to cause widespread droughts and famines, the;spread of insect-borne diseases, the displacement of populations, and a worsening of severe poverty. But here;s one thing they don;t predict: mass civilizational collapse.
Most models warn that as a result of climate change, the incredibly rapid progress;humanity has been making in life expectancies and in ending extreme poverty will stall; we could even lose decades of the progress we;ve made. If extreme poverty gets as bad as it was in 1980 due to climate change, that will be an immeasurable humanitarian failure, and hundreds of millions of people will die.
Lots of climate policy analysts agree that the;IPCC is too optimistic. In particular, the IPCC has kept insisting that it;s still possible to keep warming under 2 degrees Celsius when at this point, that;s really unrealistic. As David Roberts;put it:
Models have often included unrealistically low estimates of current and future emissions growth, unrealistically early peaks in global emissions, and unequitable estimates of emission curves in developing countries (implicitly assuming stunted development). ... Models routinely show 4 or even 6 percent annual reductions, a rate of emissions decline that has never been achieved by anyone, anywhere, ever, much less consistently over 50 years.
Six climate scientists;reviewed the accuracy of the report and Vice;s write-up;at Climate Feedback, a nonprofit that works to improve climate reporting by getting comments from scientists on striking claims in the press. This is a classic case of a media article over-stating the conclusions and significance of a non-peer reviewed report that itself had already overstated (and indeed misrepresented) peer-reviewed science,' wrote Richard Betts, who chairs the department for climate impact research at the University of Exeter and leads the European Union project that studies the impacts of extreme global warming. And some of its most outrageous claims are just wrong (for example the threat of deadly heat waves, temperatures of 30C were included in definition of deadly heat wave occurrence).
The core claim of the Breakthrough report— that 3 or 4 degrees of warming could destroy civilization — was also deeply unlikely. “While there is plenty of scientific evidence that climate change will pose increasingly existential threats to the most vulnerable individuals in society and to key global ecosystems,' wrote UCLA researcher Daniel Swain, “even these dire outcomes aren;t equivalent to the 'annihilation of intelligent life' as is claimed in the report.'
John Halstead, who studies climate change mitigation at the philanthropic advising group Founders Pledge points out that in many papers the large chance of extreme degrees of warming, is the result of the simplistic form of statistical modelling.
The paper concludes: ;It;s worthwhile to look into the worst-case scenarios, and even to highlight and emphasize them. But it;s important to accurately represent current climate consensus along the way. It is hard to see how we solve a problem we have widespread misapprehensions about in either direction, and when a warning is overstated or inaccurate, it may sow more confusion than inspiration.
Climate change wonn't kill us all. That matters. Yet it s one of the biggest challenges ahead of us, and the results of our failure to act will be devastating. That message — the most accurate message we have got — will have to stand on its own.
Climate change: main points
Under the worst-case scenario ( which is a low probability scenario): Climate Change could undermine Human civilization by 2050. If the world warms by 3 degrees Celsius, then 55% of the global population could face dangerous heat waves each year. Nearly 30% of the world's land would become arid under these conditions, and food production in agricultural zones would plummet as precipitation patterns shift. Water availability would become scarce for 2 billion people. Extreme storms, including monsoons and hurricanes, will become more common.
Even under a less severe scenario, Humanity will experience an increase in hunger and water crises, especially in developing countries. Also increased health risks due to rising temperatures and heatwaves, increased spread of pests and pathogens, loss of biodiversity and ocean acidification.
Critical global ecosystems including the Amazon rainforest, coral reefs, and the Arctic would collapse at this point. Poor countries that lack the resources to cope with these changes would become 'unviable,' and global migration patterns would reach catastrophic levels.
Climate change will not cause the extinction of the human race, but it will cause enormous human and economic, damage to our civilization. It's one of the biggest challenges ahead of us, and the results of our failure to act will be devastating.