United Nations — U.N. Secretary-General Antonio Guterres told governments to come to a September summit with concrete plans to boost climate action, as he released a flagship report on global warming by the World Meteorological Organization (WMO) on Thursday.
The destruction wrought by Cyclone Idai in southern Africa this month was a stark reminder of how climate change was hurting the planet, he said, describing how extreme weather last year disrupted a growing number of lives.
The WMO report came as Guterres drums up support for his summit to ramp up political will to tackle the climate crisis.
"I am telling leaders, 'Don't come with a speech, come with a plan'," he said to journalists.
The world's top diplomat said states should look at enhancing their national plans to reduce planet-warming emissions under the Paris Agreement to limit temperature rise.
"If not, it will be irreversible," he said.
The 2015 pact agreed by nearly 200 nations aims to keep the increase in average world temperatures to "well below" 2 degrees Celsius (3.6F) above pre-industrial times, mainly by reducing the use of polluting fossil fuels.
But the planet has already heated up by about 1C and may see temperatures warm 3-5C by the end of the century, said WMO Secretary-General Petteri Taalas.
Scientists have linked global warming to accelerating sea-level rise, shrinking sea ice, glacier retreat and extreme events like heat waves, the U.N. agency noted in its report.
A jump in the average number of people exposed to potentially lethal heat waves - some 125 million since the beginning of this century - exemplified climate change's fast-expanding cost to public health, said Guterres.
The world's warming trend is expected to continue, with the past four years the hottest on record, said the WMO report.
Several countries had already signaled they would bring more ambitious plans to the New York climate summit, said Taalas, who is among the event's organizers.
"The role of this summit is going to be that countries are allowed to speak if they promise something new," he said.
Cyclone Idai has caused massive flooding and killed more than 700 people after slamming into Mozambique and rippling through Zimbabwe and Malawi. The powerful storm bore the fingerprints of climate change, said Taalas.
The "clear link" between climate change and social instability should also alarm nations worldwide, added Guterres, who recalled historical instances of extreme weather preceding upheavals such as the French Revolution and the Arab Spring.
Across the globe, disasters affected nearly 62 million people in 2018, mostly in floods, the WMO report said.
A preliminary version of the report was released in November.
- Reporting by Sebastien Malo @sebastienmalo, Editing by Megan Rowling