World's Largest Cities See Big Increase in Hot Days
Jakarta, Indonesia's loud, busy capital city, has always had a tropical climate — hot and wet. But it hasn't always been this hot, this often.
Between 1994 and 2003, there were 28 days when the temperature in the city got above 35 degrees Celsius.
But in October 2023, it was over 35 degrees for 30 days in a row. That's right — there were more hot days that month than there had been between 1994 and 2003.
Jakarta is not alone. The world's 20 largest capital cities are having more really hot days than ever before, according to the International Institute for Environment and Development (IIED).
Over the past 30 years these cities have seen a 52% increase in the number of days that the temperature has been over 35 degrees.
And life for many of the 300 million people who live in these places is getting less comfortable and less healthy.
Of the 20 largest capitals, New Delhi in India had the most hot days between 2014 and 2023, with almost 1,600 days over 35 degrees.
That's 44% of the days during that period.
"My body can't take it," a rickshaw driver in New Delhi told CNN. Not only is he finding it hard to be outside, he's also losing business as people take air-conditioned taxis instead.
Heat in cities is often worse than in greener areas because of the "heat island effect," said Tucker Landesman from the IIED.
This is when buildings, roads and concrete absorb the heat from the sun and re-emit it, making the area warmer and keeping the heat in.
It's often the poorest people in the cities who are most affected by this, said Landesman.
He added: "Climate change is not just a future threat — it's already happening and getting worse."
