Warmer future is certain, says climate change report
The report, endorsed by 195 governments and based on more than 14,000 studies, is the most comprehensive summary to date of the physical science of climate change. He will be a focal point when diplomats meet in November at a United Nations summit in Glasgow to discuss how to step up their efforts to reduce emissions.
A growing number of world leaders, including President Biden, have endorsed the goal of limiting global warming to 1.5 degrees Celsius, although the current policies of major polluting countries are still a long way from achieving that goal. The 10 biggest emitters of greenhouse gases are China, the United States, the European Union, India, Russia, Japan, Brazil, Indonesia, Iran and Canada.
The new report leaves no doubt that humans are responsible for global warming, concluding that almost all of the increase in global average temperatures since the 19th century has been caused by nations burning fossil fuels, clearing land. forests and loading the atmosphere with greenhouse gases such as carbon dioxide. and methane which traps heat.
Climate change to date has little parallel in human history, according to the report. The past decade is probably the hottest the planet has been in 125,000 years. The world’s glaciers are melting and retreating at a rate “unprecedented for at least 2,000 years”. Atmospheric levels of carbon dioxide have not been so high for at least 2 million years.
Ocean levels have risen an average of 8 inches over the past century, and the rate of increase has doubled since 2006. Heatwaves have become much hotter since 1950 and last longer in much of the world. The weather of forest fires has deteriorated in vast areas of the globe. Extreme heat gusts in the ocean – which can kill fish, seabirds and coral reefs – have doubled in frequency since the 1980s.
In recent years, scientists have also been able to establish clear links between global warming and specific extreme weather events. Many of the deadly new temperature extremes the world has seen – such as the record-breaking heat wave that swept through the Pacific Northwest in June – “would have been very unlikely to have happened without human influence on the system. climate, ”the report says. Greenhouse gas emissions significantly worsen droughts, torrential rains and floods.