Alarm call

It happened fast. In New York City, phones lit up warning people to get to high ground. On Wednesday night, Tropical Storm IdaWhen Hurricane Ida made landfall on August 29, it was the fifth-largest hurricane in US history. On land, it weakened and became a tropical storm. drenched the city in a record-breaking downpour. Rain flooded basement flats and gushed into the subway systemDramatic videos show flooding in New York's underground public transport network. "The subway system is not a submarine," the head official said when the network was forced to close.. At least 40 people were killed.

"The climate crisis is here," said President Biden. Bill de Blasio called it "the biggest wake-up call" for the dangers of global warming. Tornados flattened homes in neighbouring New Jersey, where standing in the ruins, Phil Murphy said: "The world is changing."

It has been a summer of extremes. In June, a heat domeHot air trapped and forced down by atmospheric pressure. Unable to rise and cool, the air gets hotter and hotter. cooked the Pacific northwest. The heatwave ignited wildfiresAn uncontrolled fire that burns in a forest, grassland, or other sparsely populated area. Wildfires are becoming more common with global warming.. They burned for weeks.

In July, a year's worth of rain fell on the Chinese city of Zhengzhou. In Belgium and Germany, streets were "engulfed" and homes "swallowed" by catastrophic floods. Fires blazed across Europe.

Scientists are usually careful not to blame local weather on climate change. So a UN reportThe scientific report by the Intergovernmental Panel on Climate Change (IPCC) warned that climate change was becoming inevitable and irreversible. made headlines when it said it is now an "established fact" that human-caused global warming has led to a surge in deadly weather events.

The 1.2C increase in global temperatures means there will be more megadroughts and wildfires. But there will also be stronger hurricanes and worse floods.

According to the World Meteorological OrganisationThe UN agency responsible for climate science. Since 1970, two million people have been killed by extreme weather events, the WMO reports. there are five times more extreme weather events than fifty years ago. The conclusion, says climatologist Michael Mann, is inescapable. "We have zero years left to avoid dangerous climate change, because it's here."

The UN has declared "code red for humanity" and is calling for "immediate, rapid and large-scale" cuts in greenhouse gases. China and the US are the world's biggest polluters. Campaigners hope this year's fires and floods will push them to act.

But talks are "deadlocked". Last week, the US accused China of moving too slowly whilst China said "the ball is in the US court". They will need to agree on a way forward before the world's leaders meet for the next major UN climate change conferenceAlso known as COP26, it will be the most significant meeting since the Paris Agreement in 2015, when world leaders agreed to reach net-zero emissions by the second half of this century..

Is this the summer we finally wake up?

No. We are sleepwalking into climate chaos. The news is terrifying, but it is not going to change people's behaviour. When confronted by a scary and difficult problem like climate change, we bury our heads and try to ignore it. We need simple and positive steps that make us feel optimistic about the future.

Yes. Climate change is impossible to ignore. For many it was a problem happening elsewhere, but this summer it came to the most powerful countries. Politicians could delay difficult decisions, but now homes and lives depend on taking action. It must become the top priority and that should be a reason to be hopeful.