Fires, floods and deadly heatwaves: warning signs of a planet on the brink

Washington: The Earth is hotter today than it has been for thousands of years, as if it were All the alarms on the planet were going off at the same time.

The warnings echoed in the waterlogged mountains of Vermont, USA, where In two days, more rain fell than in two monthsAnd in India and Japan, where the flood caused devastating floods.

It is also heard on the streets of Spain, China, in the North American states of Texas and Florida, and even in Phoenix and the entire southwest of the United States, where there is a choking sound. heat wave in the next few days.

Alerts also come from oceansAnd Where the level of temperatures is already considered “more than extreme”and from the forests of Canada, where they are still active Forest fires Of a size never seen before, it emits menacing clouds of smoke that blanket the United States.

For scientists, there is no doubt about it This cacophony of alerts is caused by climate change, and it’s only going to get louder and louder as the planet continues to warm. Research shows that greenhouse gas emissions, especially from the combustion of hydrocarbons, have risen Earth’s average temperature is about 1.2 degrees Celsius compared to pre-industrial levels. Unless humanity radically changes transportation, electricity generation, and food production, The global temperature is on track to rise by more than 3°C compared to the pre-industrial era, according to the United Nations’ Intergovernmental Panel on Climate Change. If that was the case, the current calamities would be insignificant compared to the one that would be unleashed.

The only question, scientists say, is How loud the alarm bells must be for people to finally wake up.

“This is not the new normal,” says Frederic Otto, a climatologist at Imperial College London. “We don’t know what the new normal is, which will only arrive when we stop burning fossil fuels, and we’re no closer to achieving that.”

According to Otto, the arrival of summer in the Northern Hemisphere and the return of the El Niño weather pattern, which tends to raise global temperatures, add climatic tension to this season of simultaneous extreme events. But these natural phenomena happen with Human-caused climate change as a background, deepening and exacerbating its effects as never beforeWhat could once have been a typical summer storm causes catastrophic floods today, and what could have been a scorching summer day turns into a deadly heat wave.

In fact, the Fourth of July this year was the hottest on record, and the average global temperature that day was 17°C, probably the highest recorded in the last 125,000 years of the planet’s history.

Otto is the co-director of World Weather Attribution, a global network of scientists conducting real-time analyzes to determine the effects of climate change on the occurrence of extreme weather events. Since 2015, the group has identified dozens of Heat waves, hurricanes, droughts, and floods that were more likely or more severe due to human-caused warming. In fact, many of those events, like the 2021 heat wave that killed more than 1,000 Americans in the Pacific Northwest, It would be “almost impossible” in a world free of greenhouse gas emissions.

The researchers now point out that the relationship between climate change and weather disasters is quite clear. When the global average temperature is higher, heat waves reach unprecedented levels, as have recent heat waves recorded in Asia, southern Europe and northern Africa, according to a Global Weather Referral Network survey.

When temperatures rise above 40 degrees Celsius, or when extreme humidity conditions build up, the human body has a hard time keeping cool through perspiration. The most exposed and vulnerable are children and the elderly, as well as those who work outdoors or suffer from pre-existing diseases.

These are exactly the weather conditions that more than 100 million people in the southern United States will experience this week, and climate scientists like Jennifer Francis fear rising temperatures could take a toll on human life.

“Temperatures incompatible with human life are recordedsays Francis, chief scientist at the Woodwell Climate Research Center. Certain places have become uninhabitable.

I hope people realize what’s going on. Francis continues. “Every day there’s a new temperature record somewhere in the world, and it’s all related to the fact that we’re warming the planet.”

And the higher the air temperature, the more water it can hold, and The atmosphere becomes a sponge that absorbs moisture from vegetation and soil. This exacerbates droughts and sets the stage for wildfires like the one that has ravaged Canada over the past few months. Over this weekend, temperatures in Canada’s Northwest Territories approached 38 degrees Celsius, fanning pockets of fires that were already out of control.

The flip side of this phenomenon is equally disastrous: The warmer, wetter weather also increases the amount of rain that can fall during a storm. In Vermont and New York, in just two days this week, it has rained as much as it has in two months, and in such a torrential way that it exceeds the carrying capacity of the region’s saturated and mountainous soils.

Effects of heavy rain It is even more devastating in poor countries, where people and governments have far fewer resources to deal with. Rachel Pizner Kerr, a Cornell University sociologist who works with farming communities in Malawi, lost two colleagues during flash floods that hit northern Malawi three months ago.

“It is a bitter irony of life, because it is the poor countries, who are least responsible for the problem, who suffer the most from its effects.”Kerr laments.

The severity of the harsh continental weather is only matched by the conditions in the world’s oceans, which are boiling: this spring, the global average of Ocean surface temperatures are at an all-time high and remain about 1°C above average for this part of the summer.

“In a way, the situation in the oceans is more worrying than the atmospheric temperature record, because the land and air heat up and cool easily, but the temperature changes in the water are much slower,” says Ted. Polar researcher at the University of Colorado at Boulder.

“This means that the oceans are accumulating a lot of heat,” Scampos adds. “And the longer we leave that, the longer it will take for ocean temperatures to return to normal levels.”

In the Atlantic Ocean and Gulf of Mexico, higher water temperatures are likely to turn into a more violent hurricane season with increased precipitation.

And near the South Pole, where Scampos operates, record high ocean temperatures appear to have disrupted the current of cold water that normally surrounds Antarctica. In February for the second year in a row, The area of ​​sea ice across the entire Antarctic continent has reached a record low. Today, even during the months when Antarctica is engulfed in the cold of the long polar night, the ice recovers very slowly. This is bad news for the glaciers of Antarctica, which need surface sea ice to cushion the onslaught of ocean waves.

“What’s happening with sea ice in Antarctica is unlike anything we’ve seen in the past,” Scampos says and shakes his head.

It’s the image we’ve been projecting and describing for decadessays the scientist, with a hint of discomfort. “Until we fix the problem, we’ll have this weather or worse, as long as we can bear it.”

Written by Sarah Kaplan

Translated by Jaime Arambide

Washington Post