'A damning indictment': U.N. releases dire new climate change report

The latest report from the Intergovernmental Panel on Climate Change, released on Monday morning, finds that millions of people and animals have already suffered from the impacts of climate change and that the number will reach into the billions by midcentury unless the world rapidly reduces greenhouse gas emissions and keeps global temperatures from rising above 1.5 degrees Celsius over preindustrial levels.

“I have seen many scientific reports in my time, but nothing like this,” said United Nations Secretary-General, António Guterres in a statement. The IPCC is the U.N. body that assesses climate science. “Today’s IPCC report is an atlas of human suffering and a damning indictment of failed climate leadership. With fact upon fact, this report reveals how people and the planet are getting clobbered by climate change.”

“Human-induced climate change, including more frequent and intense extreme events, has caused widespread adverse impacts and related losses and damages to nature and people, beyond natural climate variability,” the “summary for policymakers” of the new 18-chapter Working Group II contribution to the Sixth Assessment Report unequivocally states.

“Widespread, pervasive impacts to ecosystems, people, settlements, and infrastructure have resulted from observed increases in the frequency and intensity of climate and weather extremes, including hot extremes on land and in the ocean, heavy precipitation events, drought and fire weather,” it adds.

The report finds that many of these effects are at the worst end of past projections. “One of the most striking conclusions in our report is that we’re seeing adverse impacts being much more widespread and being much more negative than expected in prior reports, or than expected at the current 1.09 degrees [Celsius of warming] that we have,” said Camille Parmesan, a coordinating lead author of the report and professor of geology at the University of Texas at Austin, in a Sunday press conference organized by Climate Nexus, a climate communications group. “Some of the things we’re seeing that were not expected at 1.09[°C] include diseases emerging in new areas, the first extinctions of species due to climate change, mass mortality events in trees [and] mammals.”

“There are estimates of billions of people at risk for dengue fever late in the century, as the mosquito that carries it increases” its geographical range and the length of its season, said Kristie Ebi, a co-author of the report and a professor of global health at the University of Washington. She added that if climate change continues at its current pace, there are “hundreds of millions of people at risk” of malnutrition due to reduced crop yields.

As a result, it is now a certainty that life for millions of people has been or will soon be changed dramatically. The only question is how. “The takeaway message is that we've waited too long to act,” report co-author Ed Carr, a geographer and anthropologist who teaches at Clark University in Worcester, Mass., told Yahoo News. “At this point, incremental actions aren't going to get us to a climate-resilient future. We're talking about transformational changes to the way we live. We're not talking about transforming or not transforming — the choice now is between the changes we choose and transformations that are forced upon us by a changing environment. We don't get to just say we're not going to do it. It's coming upon us one way or another.”

For example, Carr said, coastal communities are getting flooded, and they are “likely — if we don't take climate action — to be completely inundated.” In that situation, many coastal areas will become uninhabitable and force mass migration.

Alternatively, the report states, humans can reduce greenhouse gas emissions in an effort to keep sea levels from rising beyond a manageable amount. But that will require other kinds of transformational change, Carr noted, such as switching to renewable energy sources. To address the risk of malnutrition and increase the absorption of carbon dioxide, people could cut back on eating meat, he said, so that land currently used for growing animal feed can be converted to plants that more efficiently feed humans, or can be returned to a natural state.

Carr’s thoughts were echoed in a statement by President Biden’s climate envoy, John Kerry. "The question at this point is not whether we can altogether avoid the crisis — it is whether we can avoid the worst consequences,” Kerry said. “Denial and delay are not strategies, they are a recipe for disaster.”

Overarchingly, not only are the effects worse than the average of previous estimates, there are two other major developments in the IPCC’s current assessment cycle, according to the authors. One is that scientists are increasingly certain that specific extreme weather events and other devastating effects — such as mass tree deaths caused by invasive insect species — are caused by climate change and are not within the bounds of natural variability. And the other is that many of these effects are weakening the Earth’s ability to absorb greenhouse gas emissions and are therefore potentially launching “feedback loops” that will make a return to normal conditions impossible if the world overshoots its goal of limiting warming to 1.5°C.

“Increasingly since [the Fifth Assessment Report], these observed impacts have been attributed to human-induced climate change particularly through increased frequency and severity of extreme events,” states the new report. “These include increased heat related human mortality, warm-water coral bleaching and mortality, and increased drought related tree mortality.”

One example cited by the authors is the Pacific heat dome, which subjected the Northwestern United States and British Columbia, Canada, to a week of temperatures over 100 degrees Fahrenheit last June, causing hundreds of deaths. “That was virtually impossible without climate change,” Ebi noted.

Much of the report focuses on how the world has adapted, or failed to adapt, to rising temperatures thus far. For instance, natural features that absorb carbon and heavy rains, such as wetlands and tropical forests, need to be replenished, yet they are still being destroyed. “We're not taking steps that are going to make the world more sustainable over time — they're going to make us more vulnerable,” said Carr. “We continue to promote agriculture at the cost of forests, especially tropical forests. If we're going to farm in place of forests, you're going to exacerbate climate challenges.”

So far, global average temperatures have risen 1.09°C, and according to the IPCC report from last year, there is a great likelihood that the world will warm more than 1.5°C if aggressive action to cut emissions isn’t taken immediately. The hope then would be that the world would decrease emissions and increase measures to remove carbon dioxide from the atmosphere, such as reforestation and actually sucking carbon from the air and storing it underground, to return to below 1.5°C of warming.

However, if forests are devastated by pests such as the pine bark beetle, which are moving up from warmer climates and lower latitudes, that will interfere with carbon sequestration because dead trees emit carbon dioxide instead of absorbing it. The same is true for many other growing effects of climate change such as more widespread wildfires.

“We’re starting to see processes moving into place with this 1.09[°C] — such as increased forest insect pest outbreaks, tree deaths due to drought, increased wildfires, thawing of permafrost and drying of peatlands — that are actually starting to weaken the ability of the biosphere to act as a sink for greenhouse gases that humans are emitting,” said Parmesan.

The report noted that tree mortality has increased by 20 percent because of climate change in tropical, temperate and boreal ecosystems, and the “biome shifts” have made it so that the microclimate on a mountain is now equivalent to what it used to be 300 meters (984 feet) downslope.

This kind of shift, the report emphasizes, has major economic consequences. “Take the ski industry in the Northeastern United States,” Carr said. “If we stay on the trajectory we're currently on, the ski season will be at least 15 percent shorter. I grew up in southern New Hampshire. There's a big chunk of New Hampshire's economy that is based on winter tourism.”

Relative to previous IPCC reports, this one puts a greater emphasis on the disproportionate impact of climate change felt by disadvantaged groups, such as lower-income people, communities of color and Indigenous communities. “This is the first time in the report that every single chapter covers Indigenous context, and in most if not all chapters, these sections were written by Indigenous people themselves,” Sherilee Harper, a co-author who teaches public health at the University of Alberta in Canada, said at the press conference.

“Exceeding 1.5[°C] means we will experience severe levels of loss and damage, some of which will be irreversible,” said Adelle Thomas, a co-author who serves as a researcher at Climate Analytics, a Berlin-based think tank, at the press conference. “That's particularly relevant for low-income, Indigenous and marginalized communities around the world, including my home country of the Bahamas. Coastal and low-lying areas are at risk of becoming uninhabitable, but how many depends a lot on how much warming occurs.”

Therefore, Thomas concluded, “we need to simultaneously reduce greenhouse gas emissions, adapt to the risks of climate change and also address losses and damages already being experienced. And we have a very limited amount of time left to do this.”

The latest report focuses on climate change impacts, risks and adaptation for people and other living things. The first working group report, released last year, focused on the physical science of climate change. The third and final working group report, which will be released in early April, will look at how mankind can mitigate climate change.