A report from the World Resources Institute (WRI) shows what would happen in cities if global warming exceeded 3 degrees
In a +3°C scenario, nearly 600 million people would be exposed to climate dangers
We are literally rushing toward a heated future, as evidenced by the fact that this summer in Italy was the third hottest since 1800—a rather unfortunate record. But what would happen to the cities of the world with a 3-degree increase in temperature?
A possible answer comes from the World Resources Institute (WRI), which has attempted to compare a future with a temperature rise of 1.5°C to one with a rise of 3°C, focusing on the realities most susceptible to this change, such as poorer countries and overcrowded metropolises.
The results reveal a world where nearly 600 million people will be exposed to flooding caused by rising sea levels, food production will be halved, and natural habitats will suffer irreparable losses.
It is no coincidence that back in 2015, a precautionary threshold of global warming was set at 1.5°C to avoid discovering the real consequences of global warming.
What would happen to cities if global temperatures rose by 3 degrees?
New data provided by WRI analyze the climate dangers of a 3-degree rise compared to the 1.5-degree scenario within the urban context of over 1,000 global cities, which currently host about 26% of the world’s population (2.1 billion people).
Most cities would face heatwaves lasting over a month, with energy demand for air conditioning skyrocketing. Infrastructure would be severely tested, leading to significant inequalities between wealthier and poorer segments of the population, as well as macroeconomic consequences on a global scale.
If we also consider that by 2050, an additional 2.5 billion people will move to cities, it means that two-thirds of humanity will have to deal with climate change.
Month-Long Heatwaves
If last August felt too hot with its 2.38 degrees above average, imagine a heatwave lasting nearly a month.
According to data from the WRI study, in a world with a 1.5°C temperature increase, heatwaves could last an average of 16.3 days, affecting about 3% of the world’s cities.
With a 3-degree rise, over 16% of the world’s largest cities would be involved (302 million people) in heatwaves lasting an average of 24.5 days.
This record could reach up to 36.3 days in geographical areas like the Middle East and North Africa.
Similarly, the frequency of heatwaves would also increase:
- In a world at +1.5°C, the average city would experience 4.9 heatwaves per year;
- While with a 3°C increase, heatwaves would rise to 6.4 per year.
Currently, only 8% of those living in the hottest and poorest areas have air conditioning
More hot days mean an increased cooling demand, but the response varies by geographical area and social class.
A temperature increase of 1.5 degrees would double the energy demand for cooling for about 8.7 million people in a handful of global cities.
A 3-degree rise would double the demand for 195 million people.
Despite the fact that air conditioning is currently less commonly used in low-income cities, demand is expected to rise in tandem with population and economic growth in these areas. This is the case in India, which, according to the WRI study, will match or even exceed Europe’s number of air conditioning units by 2050.
But without public policies or investments, the outcome will inevitably be inequality. Only about 8% of the 2.8 billion people living in the hottest and often poorest areas of the world currently have air conditioning in their homes. In India, it is estimated that over 215 million people in cities are already at risk of heat-related health problems due to a lack of cooling infrastructure.
Download the complete WRI study containing data from 14 different climate risk indicators related to temperature increases for 996 global cities under the +1.5 degree and +3 degree scenarios.
