This story was originally published on protector And copied here as Climate Service Desk Cooperation.

“This is clear.” These three distinctive words are the first words in the new report of the Intergovernmental Panel on Climate Change. The climate crisis is clearly caused by human activities, and it has clearly affected every corner of the earth’s land, air and sea.

This report, written by hundreds of world’s top scientists and signed by governments around the world, concludes that the situation could get worse if the slim chance of avoiding a temperature rise above 1.5 degrees Celsius (2.7 degrees Fahrenheit) is not immediately seized. .

The scientific language of the report is cold and clear, but it cannot conceal the heat and chaos that global warming is bringing to the world. We have caused 1 degree Celsius (1.8 degree Fahrenheit) heating, which is dangerously close to the 1.5 degree Celsius dangerous limit agreed in the Paris climate agreement. Since the 1980s, the downpour has been accelerating.

The accelerated melting of ice has poured trillions of tons of water into the ocean, where the oxygen content is declining- Suffocating ocean – The acidity is rising. The sea level has risen by nearly 8 inches, and now there are more irreversibly baked.

The report shows that greenhouse gases emitted by fossil fuel burning, forest destruction and other human activities are now clearly destroying the mild climate at the beginning of civilization. The carbon dioxide content in the air is now at the highest point in at least 2 million years.

When was the last time we saw heating up so fast? At least 2,000 years ago, maybe 100,000 years ago. The temperature is so high? At least 6500 years. Sea level rises so fast? At least 3000 years. The ocean is so acid? Two million years.

The report pointed out that all this has hurt people all over the world. The report stated that since the 1950s, the heat waves and torrential rains that caused flooding have become more intense and frequent, affecting more than 90% of the world. In more than 90% of areas with good data, droughts are intensifying. Since the 1970s, the probability of an increase in the number of major hurricanes and typhoons has exceeded 66%.

What about the future? Some heating is already inevitable. The IPCC found that no matter what happens to emissions, we will definitely reach 1.5 degrees Celsius in the next 20 years. The only good news is that maintaining 1.5C is not impossible.

But scientists say that this will require “immediate, rapid and large-scale reductions” of emissions, and there are no signs of this. Even if the emissions are reduced, the slower speed will result in a temperature of 2 degrees Celsius (3.6 degrees Fahrenheit), and all life on Earth will suffer more.

If emissions do not decline in the next few decades, heating at 3 degrees Celsius (5.4 degrees Fahrenheit) looks likely to be a disaster. According to the report, if they do not fall at all, then we are expected to reach 4 to 5 degrees Celsius (7.2 to 9 degrees Fahrenheit), which is the end of the world.

The report clearly pointed out that the climate crisis has no cliff edge. Every ton of carbon emitted increases the impact and risk of extreme heat, floods and droughts, so every ton of carbon is important. The report shows that it is never too late to take action. Instead, the real question is how bad will it get?

For example, extreme heat waves that are expected to occur once every 50 years without any global warming have occurred once every ten years. With the increase of 1.5C, this situation will occur approximately every 5 years; 2C, every 3.5 years; and 4C, every 15 months. More heating also means more disruption to monsoon rains on which billions of people depend.

More emissions also mean that land and oceans are weaker in absorbing carbon pollution, making heating worse. By immediately reducing emissions quickly, nature can still absorb 70% of our emissions. If there is no reduction, it drops to only 40%.

The most straightforward part of the report begins: “Many changes due to past and future greenhouse gas emissions are irreversible for centuries to thousands of years.” This especially affects the world’s oceans and ice, which absorb the world. 96% of the heat, which means that the ice will continue to melt, and the ocean will rise to many of our crowded coastal cities.

By the end of the century, the possible range was approximately between 3 and 40 inches, or as high as 3.3 feet. But the report warns that it may exceed 6.5 feet by then, or 16 feet by 2150. Extreme sea-level events, such as coastal floods, have occurred only once a century in the recent past, and are expected to occur in at least 60% of the places every year by 2100.

The author of the report, Professor Jonathan Bamber of the University of Bristol in the United Kingdom, said: “It seems that there is still a long way to go, but there are already millions of children who should live to the 22nd century.”

Many scientific advances since the IPCC’s last comprehensive report in 2013 mean better predictions for specific regions of the world. It found that no place was safe. For example, even under heating conditions of 1.5C, heavy rains and floods are expected to intensify in Europe, North America, and most parts of Africa and Asia.

Catherine Heho, Chief Scientist of The Nature Conservancy, said: “We can no longer assume that citizens of wealthier and safer countries such as Canada, Germany, Japan, and the United States will be able to survive the worst consequences of a rapidly unstable climate. “. “It is clear that we are all in the same boat-facing challenges that will affect each of us in our lifetime.”

This report is the sixth report of the IPCC, but it is the first report to thoroughly assess the risk of a tipping point.These are sudden and irreversible changes to critical earth systems that have a huge impact Getting more and more attention from scientists. This The collapse of the main Atlantic currents, Ice cap, or Amazon rainforest The report warned that “cannot be ruled out.”

Dave Reay, a professor of carbon management and education at the University of Edinburgh in Scotland, said: “As for the tipping point, it is clear that for every additional ton of carbon dioxide emitted today, we will be pushed into the minefield of feedback effects tomorrow.”

So what can be done? The last part of the IPCC report discusses how to limit future climate change. It found that since 1850, humans have emitted 2,400 billion metric tons (26.5 billion tons) of carbon dioxide, and we can only leak another 400 billion metric tons (441 billion tons) to have a 66% chance of maintaining 1.5C.

In other words, we have consumed 86% of our carbon budget, although the report says that science is very clear that if emissions are reduced, the temperature will stop rising within a year or two, and the increase in fatal extreme events will be strictly limited.

IPCC Secretary Abdalah Mokssit said: “Unless greenhouse gas emissions are reduced quickly and on a large scale immediately, limiting the temperature rise to 1.5C will be impossible.”

“But we never prescribe any policy to any country-the government makes the decision.”

Scientists speak louder and clearer now than ever before. Now is the time for politicians to take action.

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