Climate change report: Humans are causing widespread and irreversible impacts, says IPCC

Pastoralists from the local Gabra community walk among carcasses of some of their sheep and goats on the outskirts of a small settlement called 'Kambi ya Nyoka' (snake camp) suspected to have succumbed due to sudden change in climate in Marsabit county January 29, 2022. - A devastating drought in Kenya late-last year, that appeared to give way to flash storms that yielded flooding and chilly weather conditions in early 2022, has seen pastoral communities in the east african nation's arid north lose their livestock, first to drought and then floods and cold. (Photo by Tony KARUMBA / AFP) (Photo by TONY KARUMBA/AFP via Getty Images)

Pastoralists in Kenya among the bodies of sheep and goats that died after a dramatic change from drought to cold and wet weather

TONY KARUMBA/AFP via Getty Images

Climate change is already wreaking widespread, pervasive and sometimes irreversible impacts on people and ecosystems globally, according to a landmark report warning it has become increasingly clear there are limits to how much humanity can adapt to a warming world.

The report by the Intergovernmental Panel on Climate Change (IPCC) found that up to 3.6 billion people live in areas highly vulnerable to climate change, largely from extreme heat, heavy rainfall, drought and weather setting the stage for fires. During a press conference, UN secretary general Antonio Guterres called it “an atlas of human suffering”.

Since the last assessment by the panel eight years ago, it has increasingly been possible to pin the impacts of extreme weather events on human-made climate change. A clear message from the 35-page summary for policy makers (the full report is 3675 pages) is that holding warming to the 1.5°C goal of the Paris Agreement will limit the impacts and make adaptation more feasible.

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“We have an increased understanding that there are limits to adaptation,” says Rachel Warren, a lead author on the report, based at the University of East Anglia, UK. “What has come out is a really, really strong message that at 2°C the risks are several times greater than they are at 1.5°C. Many things become much, much more difficult to manage at 2°C than 1.5°.” Guterres put it bluntly: “Delay means death.”

Despite the commitments nearly 200 countries made in the Glasgow Climate Pact at the COP26 summit last November, the world is still on track for more than 2°C of warming.

The report finds that climate change is already affecting people’s physical health and, for the first time explicitly in an IPCC report, their mental health too. Helen Adams at King’s College London, an IPCC lead author, says the main mental toll is from extreme weather impacts, such as dealing with flooded homes, but also through “eco anxiety”.

Climate change’s burdens are falling unequally on the richest and poorest, says the report. The world’s most vulnerable people are found to be in mostly low-income  nations in West, East and central Africa, South Asia and South America, as well as those living in island states and Arctic regions. Deaths from floods, droughts and storms in those regions were found to be 15 times higher than the least vulnerable areas, mostly high-income nations such as Canada and the UK, between 2010 and 2020.

During the press conference, Inger Anderson of the UN Environment Programme said the report showed impacts are here now, not just in the future: “Climate change isn’t lurking around the corner waiting to pounce, it’s already upon on us, raining down blows on billions of people.”

Overall, the economic impact of a rapidly warming world has been adverse, according to the report. But there have been economic positives regionally, including for farming, tourism and lower energy demand.

The IPCC highlights the impact on cities, now home to more than half the global population. Urban areas are increasingly being hit by heat, floods and storms affecting energy and transport and aggravating air pollution.

The 2030s and 2040s will bring an unavoidable increase in hazards for people worldwide because there is already 1.5°C of warming baked in by our past greenhouse gas emissions. By mid-century, around a billion people will be at risk of coastal impacts such as flooding, including those in small island states, some of which face an “existential threat” later this century. If the world warms by 2°C, that will endanger food security, leading to malnutrition in some regions.

It isn’t only humans bearing the brunt, but nature too: climate change is thought to be responsible for at least two species’ extinctions. If global average temperatures rise by 1.5°C, up to 14 per cent of species on land will be likely to face a very high risk of extinction in future. At 3°C, the figure is up to 29 per cent.

However, Adams cautions against being fatalistic in the face of dire projections, because they hinge on how much societies cut their emissions and how much they adapt. “Yes, things are bad. But actually, the future depends on us, not the climate,” she says. The report finds that holding warming to 1.5°C “substantially” cuts the losses and damages from climate change, but “cannot eliminate them all”.

Attempts to adapt to a warming world, such as building flood defences and planting different varieties of crops, have made progress since the last assessment in 2014. But they fall far short of what is needed, they are uneven globally and there is growing evidence that adaptation can have negative side effects, such as sea defences causing knock-on erosion along coasts. “Most observed adaptation is fragmented, small in scale, incremental”, says the report.

Published on the fifth day of the Russian invasion of Ukraine, one of the report’s authors says the war risks derailing focus and action on climate change. “If we’re going back into a world of a cold war, thinking about climate change is something which we then don’t do with the urgency with which we need,” says Daniela Schmidt at the University of Bristol, UK.

During Sunday’s final approval of the report, which is signed off line by line by governments, the head of the Russian delegation reportedly told colleagues: “this [war] is not the wish of all the Russian people and the Russian people were not asked”. The Ukrainian delegation asked colleagues to continue and expressed how upset they were the war “will detract from the importance” of the report, Climate Change 2022: Impacts, Adaptation and Vulnerability.

The assessment, part of the sixth round of reports by the IPCC since the first in 1990, closes with an urgent message: “Any further delay in concerted anticipatory global action on adaptation and mitigation will miss a brief and rapidly closing window of opportunity to secure a liveable and sustainable future for all.”

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