November 23rd, 2010
11:08 PM ET

NASA study finds Earth's lakes are warming

Satellite data largely agreed with temperature trends taken from buoys in the Great Lakes, NASA says.

The temperatures of Earth's largest lakes have risen in the past 25 years as a result of climate change, according to a new NASA study.

NASA used satellite data to measure the surface temperatures of 167 lakes worldwide and found an average warming rate of .81 degrees Fahrenheit per decade and in some lakes, as much as 1.8 degrees Fahrenheit per decade, NASA said Tuesday.

The greatest increases were in the mid- to high- latitudes of the Northern Hemisphere, in a pattern consistent with changes associated with global warming, said Simon Hook, a scientist with NASA's Jet Propulsion Laboratory in California.

"The key thing is it’s an independent study that provides a new of piece evidence that warming's taking place; and it's made possible through a comprehensive view that the satellite data provides, by allowing us to look over the entire world, as opposed to a particular region," he said.

"From a scientific point of view, small differences in lake temperatures can have big change in a lake's ecosystem - a new fish species that people don't want, new plants; so from our point of view, what we want to do next is understand what the impact of these changes is going to be on the lake's ecosystem."

The study's results incorporated other techniques to verify the satellite data, such as direct measurements of water temperature, wherever possible, Hook said.

The lakes were chosen for inclusion in the study based on their size - typically at least 193 square miles or larger, so conditions on land would not influence the results. The study used nighttime data from summer months over the past 25 years to avoid interference from cloud cover or ice.

Of the 167 lakes surveyed, researchers were able to use data from 104, with 41 producing results that were "statistically significant," he said. Four lakes showed signs of cooling, but the differences were small enough to render them neutral, Hook said.

The satellite temperature trends largely agreed with trends measured by buoys in the Great Lakes, Earth's largest group of freshwater lakes in terms of total surface area and volume.

"There are ways to verify data independently of the satellite data, and we used those to confirm our findings," he said. "From this particular data set, we can say in the last 25 years, looking at these lakes, there seems to be a significant warming trend."

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Filed under: Climate change • Science • Space • Weather
soundoff (115 Responses)
  1. Veritas

    What a revelation hmmmmm!

    November 24, 2010 at 9:25 am | Report abuse |
  2. DandyStyker

    Just another bit of science for religious fanatics (i.e., the Republican leadership) to ignore. Along with evolution (biology), geophysics, and cosmology.

    November 24, 2010 at 10:20 am | Report abuse |
    • TampaMike

      Awww! Cmon Dandy! Did you have to use the "R" word? I was actually enjoying the comments for a change...

      November 24, 2010 at 10:39 am | Report abuse |
  3. Chuckled

    u people crack me up. Didn't you read the story, it's that giant magnet over in swiss land that has cause the temp to rise in "The Great Ponds". They built the magnet to block off the Death Star thats coming in 2012.

    November 24, 2010 at 10:20 am | Report abuse |
    • Mmmm

      U people? I believe in magnetized heating...don't they call it a microwave oven...ready to eat seafood without BP additives! Yum-yum!

      November 24, 2010 at 12:08 pm | Report abuse |
  4. Where

    So we can pinpoint lakes from space and tell the exact degree they are all the time but Osama still eludes us?

    November 24, 2010 at 10:22 am | Report abuse |
    • andragogy

      Luckily for us lakes are much larger in volume, can have buoys with temperature guages float in them, and usually they aren't trying to elude the US government. Even I can take and keep track of a lakes temperature over the course of many decade. Maybe if we can get close to Osama we can stick a thermometer in him to.

      November 24, 2010 at 10:46 am | Report abuse |
  5. klem

    Yea yea.. we're all going to die..blah blah snore.. I think we've heard this one last year didn't we? Or perhaps the year before, I mean they all sound the same after awhile. The world's going to end, prepare to meet thy maker!

    I'll be watching the game. Just leave me a message if the world has ended, ok?

    November 24, 2010 at 10:22 am | Report abuse |
  6. Ivan

    The comments are better than the article

    November 24, 2010 at 10:22 am | Report abuse |
  7. Mike

    Earth's lakes are getting warmer – well, actually we can't use the data from 38% of our examples, so 62% of the Earth's lakes are getting warmer, except we need to discount 61% of them as statistically insignificant because otherwise we'd have to say 4% of them are actually getting cooler.
    I applaud CNN for at least reporting that detail, but shouldn't the headline have read "NASA study finds that 25% of Earth lake's are getting warmer"

    November 24, 2010 at 10:23 am | Report abuse |
    • M

      Well put.

      November 24, 2010 at 10:30 am | Report abuse |
    • David Hillman

      You don't seriously expect climate scientists to admit when their data doesn't support their theory, do you? Haven't we learned that lesson by now? They have their religion, and will cherry-pick or modify data to prove it as necessary.

      That's not to say that the planet is, or is not, getting warmer... just that there is no credibility left in the climate science field.

      November 24, 2010 at 11:22 am | Report abuse |
    • Peter E

      I love how American voters and politicians will discount science if there are some numbers of data that cannot be used. And yet they have no questions about believing that tax cuts create jobs, even though there is practically zero statistical correlation between tax rates and unemployment. Yes, you can check the graphs for the past half century on that! They also have no trouble touting political poll numbers based on survey of only about 1000 voters as a representation of all America... when it suits them. When it doesn't, THAT's when they point out it's only 1000 people who have been surveyed.

      November 24, 2010 at 12:00 pm | Report abuse |
    • Limbaugh is a liberal

      OMG, it's ten degrees warmer now than it was 2 hours ago! And it's November! Temperatures are supposed to be dropping! The theory of seasons is a lie!!! We can't prove there will be a winter in December!

      November 24, 2010 at 12:13 pm | Report abuse |
  8. jimiatlas

    Well, at least swimming will be more comfortable. What's bad about that?

    November 24, 2010 at 10:23 am | Report abuse |
  9. hatethecold

    Good I hate taking a cold swim.

    November 24, 2010 at 10:25 am | Report abuse |
    • teepee

      good one man

      November 24, 2010 at 10:50 am | Report abuse |
  10. S. Falls

    Where is George W Bush to rewrite this NASA report?!?

    November 24, 2010 at 10:28 am | Report abuse |
  11. n

    In the case of the great lakes, there was a drought which reduced water levels as well. That drought is a cyclical thing, rather then a climate change thing. I'd say this "independent study" needs a closer examination of its assumptions. I wish you guys would actually investigate reports, rather then just copying them off the same RSS feed i get.

    November 24, 2010 at 10:29 am | Report abuse |
  12. Chuckled

    (looking in the utility closet for the "2012 survival kit")

    Found it! The ol' trusty MacGyver knife! Bad boy turns into a helicopter when thrown correctly.

    November 24, 2010 at 10:31 am | Report abuse |
  13. phil

    Let's eat, drink, and be merry for TOMORROW we are to die. Same old blah blah blah you hear each year as things worsen.

    November 24, 2010 at 10:31 am | Report abuse |
  14. cavemanstyle

    If anybody really cared about global warming, we'd have a faster transition from CO2 emitting cars to Solar charged electric vehicles. The actual usage of new technology as opposed to what's actually available would astound you.. we're living in the stone age compared to what we have available to use and develop on a large scale. Put me in charge.. I'll make it happen.

    November 24, 2010 at 10:36 am | Report abuse |
  15. phil

    There is no rush to reduce carbon levels. Why? Because reducing atmospheric pollution levels will make the earth warm even faster. Pollution provides shade. Simply removing this shade only makes it hotter. It's a real catch-22 situation. darned if you do and darned if you don't.

    November 24, 2010 at 10:44 am | Report abuse |
    • DavetheG

      umm, carbon dioxide actually traps heat and keeps the earth warm. so the less there is the more heat escapes and causes cooling.. idiot

      November 24, 2010 at 11:11 am | Report abuse |
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