UN climate report shows world blindly flying in storm – POLITICO

TL; DR, global warming is bad and getting worse.

But a sprawling assessment of tens of thousands of scientific papers on the state of the planet, published Monday, revealed another troubling truth: Scientists still don’t have answers to many of the questions that will determine how far the world face the worst. of climate change.

In its latest report, the Intergovernmental Panel on Climate Change (IPCC) describes a world of long-predicted impacts now coming with shocking power. Human suffering, especially among the poor, will increase rapidly over the coming decades. The symbolic limit of 1.5 degrees Celsius will almost certainly be exceeded.

It is still possible to avoid the darkest scenarios, with the transition to clean energy happening faster than expected, the report also notes.

But in many critical areas, IPCC scientists say the world is flying blindly into the storm.

By the time they release their next report – at the end of this decade – there will be more clarity on where global temperatures will peak. Green policies will have triggered social and economic transformation, with major benefits – and major upheavals.

This means that there are still far too many unknowns to say with certainty how and when the most devastating impacts will occur.

“In general, science always lags politics,” said Piers Forster, IPCC author and director of the Priestley International Center for Climate at the University of Leeds.

“We need a living lab mentality to test ideas in an open and transparent way to really learn how to transform society. Otherwise, we will opt for technologies based on who shouts the loudest rather than the best.

How extreme will the extremes become?

Extreme weather events in recent years, including the 2022 heatwave that shattered temperature records across much of Europe, and the floods that devastated Pakistan last year – surprised some of the world’s top climate scientists with how were outside the normal range.

Experts still know relatively little about when and where these types of extreme weather events will occur. Or what happens when two events, like a drought and a heat wave, hit the same place simultaneously. That’s because scientists have tended to look at broader averages across regions, rather than the most intense extremes in specific locations.

“We did not ask the models [to] find an outrageously high temperature figure, like 50 degrees in Canada” — a milestone reached during a heat wave in 2021 — “and determine the probability or if it is possible,” said Friederike Otto, author of the IPCC report and senior lecturer at Imperial College London. “And I think that’s why these are surprises.”

Who are the vulnerable people?

As leaders seek to contain the worst impacts of global warming, knowing where to focus efforts will be critical.

The IPCC has classified between 3.3 and 3.6 billion people, nearly half of the total world population, as the most vulnerable, with people in developing countries being the hardest hit.

Even as the report was released, Mozambique, Malawi and Madagascar were locked in a record and repeated onslaught from Cyclone Freddy. The region is still recovering from Cyclones Idai and Kenneth in 2019.

But in rich countries too, the poor, the elderly, the sick, the young and the marginalized will be less equipped to face the challenges ahead.

Pinpointing precisely who is most at risk requires blending the physical sciences with social, political and economic disciplines. This discussion is still in its infancy.

When are we going to reach frightening tipping points?

The IPCC has expressed “medium confidence” that an abrupt change in Atlantic currents that could plunge Europe into an ice age will not occur before 2100.

Exciting? Maybe. But when it comes to the most dangerous and sudden potential impacts of climate change, the level of certainty among scientists is still worrying.

The field remains filled with guesswork. But in a paper last year – which was published too late to be included in the IPCC report – scientists identified 16 of these so-called tipping points, including the collapse of the main ice caps of the Earth, which would trigger massive sea level rise; and the loss of permafrost, leading to a sudden release of carbon dioxide and methane, further fueling global warming.

What is clear is that there is a direct correlation between rising temperatures and the likelihood that the changes will become increasingly irreversible. For example, according to the IPCC, with a rise in global temperatures of between 2°C and 3°C, Greenland and West Antarctica would “almost completely and irreversibly” lose their ice caps for millennia.

Should we darken the sun?

Science fiction became reality late last year when an American startup called Make Sunsets launched balloons that may have released reflective sulfur particles into the sky over Mexico.

Managing solar radiation – as it’s called – is just one of the few hacks talked about for cooling the planet. But none of them come without drawbacks. We don’t even know if they will work. And the fear is that rogue actors will take matters into their own hands.

“There is not enough science, there is no governance,” said Pascal Lamy, the former head of the World Trade Organization who chairs the Climate Overshoot Commission.

The IPCC’s conclusion that there is almost no chance of avoiding breaching the 1.5°C limit has sparked more interest in areas once avoided as defeatist or worse. The White House has called on researchers to contribute to a new “climate intervention” research plan.

It remains deeply controversial. “Science is divided on this. We have some very reputable scientists who say let’s take a serious look at it. Another small part of science says, ‘No, no! It’s Dr Strangelove and so on,'” Lami said. “But what is certain is that if we are successful in a proper governance framework, it will have to be linked to proper science.”

Is the IPCC fit for purpose?

IPCC members include many governments that are not happy to hear prescriptive views on how to structure their economies. So, as the world increasingly turns to questions of transformative change, some scientists and policymakers wonder if the institution is fit to provide the answers needed.

“The IPCC is a bit like the Catholic Church: a very conservative institution with seemingly immutable rituals, with stamina and driven by an important mission,” the German economist and chairman of the European Science Advisory Board told Die Zeit. climate change Ottmar Edenhofer. .

“What we don’t know is what kind of governance, what political instruments need to be put in place now. I doubt that the IPCC, with its intergovernmental structure, can help us here,” Edenhofer said.