Satellite data shows that climate change is warming Earth's lakes
A new study has brought together morethan 25 years of satellite data, combined with ground measurements,to assess the state of Earth's lakes. The results show a troublingrise in temperature that the researchers claim could have a bigimpact on our environment.
The study made use of a combination ofsatellite temperature readings and ground-based measurements of 235lakes on six different continents. While the satellite readingsprovide a global picture of lake temperatures, they only coversurface readings, while ground-based observations detect temperaturesthroughout the water bodies.
According to the researchers, thiscombination monitoring method – alongside the geographically diversenature of the sample – provides the most complete picture of how laketemperatures are changing globally.
Specifically, the results show that theaverage temperature in the lakes has been rising by 0.61 degreesFahrenheit every 10 years. While that might not seem toosignificant, it's a higher rate of warming than witnessed in eitherthe atmosphere or the ocean, and the long-term effects could bepronounced.
The researchers predict that thecontinued increase in lake temperature will bring with it an increasein algal blooms by a much as 20 percent over the next century,lowering the water's oxygen levels while increasing toxicity for fish and animal life. Additionally, the temperature rise could cause an overall rise in methane emissions by as much asfour percent in the coming decade.
The temperature increases area little less pronounced in warm-water tropical lakes, but even thenare still significant enough to have a negative impact on the fish.This could be a particular problem in areas such as the African GreatLakes, where fish is a major source of food.
All in all, if the temperature rise isleft to continue, it could have significant negative impacts onthe environment.
"The pervasive and rapid warmingobserved here signals the urgent need to incorporate climate impactsinto vulnerability assessments and adaptation efforts for lakes,"say the researchers.
The findings of the study werepublished in the journal Geophysical Research Letters.