Seals in Russia's Lake Baikal are one of many species likely to be affected by warming lake waters. S. Gabdurakhamanov

Many are growing hotter quicker than the oceans and atmosphere.

You hear a lot about the problems posed by warming oceans: sea-level rise, habitat disruption, globe-spanning die-offs of coral. What you hear less of is how climate change is affecting the world’s lakes, though new research suggests we should start planning for this problem yesterday.

Using satellite and ground data, researchers at NASA and elsewhere probed more than half of the planet’s bodies of fresh water (235 lakes total). What they found was alarming: Lakes are heating up an average of 0.61 degrees Fahrenheit every decade, which is faster than the warming rates of the oceans and atmosphere. At higher latitudes the warming is even more pronounced at 1.3 degrees a decade, which jibes with the fact that earth’s poles are experiencing a tremendous amount of toastiness.

Red spots mark lakes that have warmed over the past 25 years. (Illinois State University / USGS / California University of Pennsylvania)

Several things appear to be influencing the heating of the lakes, including a rise in global air temperature, less cloud cover allowing more solar radiation to reach the water, and protective ice covers disappearing earlier in the year. And while this trend might make for more-comfortable swimming holes, it’s likely to have drastic effects on the environment.

Warmer lakes will allow more methane to seep into the air—about a 4 percent increase in the next decade, according to the researchers—and methane is much more potent a greenhouse gas than CO2. And blooms of algae are expected to leap 20 percent over the next century thanks to the balmy water, with about 5 percent of them likely being toxic. If you think staying out of the water will prevent algae from causing you and your pets harm, consider fish that consume the organisms can pass on illnesses to people who eat them, including a type of poisoning that makes “cold things feel hot and hot things feel cold.” (That specific malady is expected to spread as temperatures rise, natch.)

The transformation of lakes could also have profound impacts on human economies and food networks. As one of the 60-plus scientists who took place in the research explains:

“Lakes are important because society depends on surface water for the vast majority of human uses—not just for drinking water, but manufacturing, energy production, irrigation and crops,” said paper coauthor Stephanie Hampton of Washington State University. ”Protein from freshwater fish is especially important in the developing world.”...

Warm-water lakes have experienced less dramatic temperature increases, but their waters may have already nearly reached the highest temperatures fish can tolerate, Hampton said.

That’s particularly important in the African Great Lakes, home to one quarter of the planet's freshwater supply and an important source of fish for food.

The migebuka fish in Africa’s Lake Tanganyika is another species facing possible peril in warmer waters. (Catherine O’Reilly)

About the Author

Most Popular

  1. Environment

    A 13,235-Mile Road Trip for 70-Degree Weather Every Day

    This year-long journey across the U.S. keeps you at consistent high temperatures.

  2. Design

    Paris Will Create the City's Largest Gardens Around the Eiffel Tower

    The most famous space in the city is set to get a pedestrian-friendly redesign that will create the city’s largest garden by 2024.

  3. a photo of a police line barricade in front of a sidewalk
    Transportation

    What We Fight About When We Fight About Parking

    The urban economist Donald Shoup collects reports of violence that erupts over parking spaces. To him, disputes between drivers are signs of a bigger problem.

  4. Opponents of SB 50.
    Equity

    Despite Resistance, Cities Turn to Density to Tackle Housing Inequality

    Residential “upzoning” policies being adopted from Minneapolis to Seattle were once politically out of the question. Now they’re just politically fraught.

  5. A map of the money service-class workers have left over after paying for housing
    Equity

    Blue-Collar and Service Workers Fare Better Outside Superstar Cities

    How much money do workers have after paying housing costs? For working-class and service workers in superstar cities, the affordable housing crisis hits harder.