MagazineEarth Day 2020

See which cities will feel the brunt of climate change

The whole planet will feel climate change's impacts over coming decades. But some cities will see more dramatic changes in temperature or precipitation than others.

By Kennedy Elliott and Alejandra Borunda

PUBLISHED

Cities where...

the coldest temperatures are increasing the fastest between now and 2070

the warmest temperatures are increasing the fastest

precipitation is changing the most

it will be hot and dry

it will be extremely wet

Cities where the coldest temperatures are increasing the fastest between now and 2070

... and where the warmest temperatures are increasing the fastest

... and where it will be hot and dry

... and where precipitation is changing the most

... and where it will be extremely wet

Cities where the coldest temperatures are increasing the fastest between now and 2070

... and where the warmest temperatures are increasing the fastest

... and where it will be hot and dry

... and where it will be extremely wet

... and where precipitation is changing the most

Cities where the coldest temperatures are increasing the fastest between now and 2070

... and where the warmest temperatures are increasing the fastest

... and where it will be hot and dry

... and where precipitation is changing the most

... and where it will be extremely wet

Cities where the coldest temperatures are increasing the fastest between now and 2070

... and where the warmest temperatures are increasing the fastest

... and where it will be hot and dry

... and where it will be extremely wet

... and where precipitation is changing the most

This story is part of the pessimistic argument for the future of the planet in our special issue on Earth Day. Read the optimistic argument and the rest of our stories here.

More and more of us live in urban areas. Today, some 55 percent of the world lives in cities, and a quarter of all humans live in the 2,500 most populous cities. That percentage is expected to increase dramatically in the coming decades. By 2050, as the global population swells and urbanizes, about 70 percent of people will live in metropolises.

Earth’s climate, meantime, will continue to change in response to ever-rising greenhouse gas concentrations in the atmosphere. Further warming will induce dramatic changes in nearly every corner of the planet. Some of those effects are already playing out.

Many of the impacts of future warming will be felt by the growing population of city dwellers. Cities concentrate people, infrastructure, activity, and many other resources into tight spaces, which means they’re particularly vulnerable to the effects of climate change. Hotter temperatures put extra stress on human bodies, asphalt-covered roads, and more; more intense droughts can tax water systems; more intense rainfall can flood cities’ drains.

National Geographic partnered with Matt Fitzpatrick, an ecologist at the University of Maryland Center for Environmental Science, to look at how temperature and precipitation patterns in many of the major urban areas of the world could change by 2070 if significant efforts to curb greenhouse gas emissions are not made quickly—the “RCP 8.5” scenario.

The conclusions are clear: Just about everywhere in the world will experience shifts in seasons, hotter highs, and more extreme wet and dry periods. Some urban areas will feel more intense changes than others. But the alarming predictions are not set in stone. Today’s decisions can still influence tomorrow’s experience.

In

maximum temperatures will degree during summer months, from degrees in 2020 to degrees in 2070.

Summer maximum temperature, degrees Fahrenheit

2020

2070

Warmer warms

Cities are affected more than rural areas by increasing air temperatures because they’re already hotter. Concrete, steel, wood, and other infrastructure materials trap more heat than a natural landscape does: the so-called urban heat island effect.

Unchecked climate change will drive temperatures up dramatically in every one of the 2,500 locations studied. During summer, the highest high temperatures are projected to increase by an average of 8 degrees Fahrenheit by 2070. In some places, the heat will be even more extreme. Summer temperatures in Urmia, Iran, for instance, will experience a 15-degree uptick, with average hot temperatures hovering at 98 degrees Fahrenheit.

Currently, only 9 percent of the cities studied have summer maximum temperatures that exceed 100 degrees Fahrenheit, but that number will more than double by 2070. Among those future cities experiencing intense heat will be Grand Junction, Colorado, where today’s summer maximum temperatures of 90 degrees are projected to hit 100 degrees in 2070.

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