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. jay

    We need to go back to coal for heating homes. Back in the early 70s everyone was yelling about the coming ice age because of the coal usage so we stopped and started the cycle of warming... so, we go coal for another 40 years, cool things down, then go back to oil, then coal, then...

    November 24, 2010 at 1:20 pm | Report abuse | Reply
  2. CaptainObvious

    Yeah cuz were not thinking about terraforming Mars by pumping CO2 into it's atmosphere. CO2 has no effect on global temps. You're right skeptics.

    November 24, 2010 at 1:40 pm | Report abuse | Reply
  3. CaptainObvious

    It's really easy to fix man's impact on the atmosphere. For every business or home that takes the place of a forest or grassy plain there needs to be the exact sq footage of foliage planted somewhere else to compensate for that loss. Every lumber mill should be required to replace trees they cut down (many do already). Every factory that expends C02 as a waste product needs to offset that somehow by trapping it ( costly and inefficient ) or plant more vegitation somewhere that will compensate (much easier and cheaper. As more land is developed the earth loses it's ability to filter the CO2 that already exists from animals, fires and volcanic activity. It's a scientific fact that CO2 traps heat. Methane also has some effect on the atmosphere. We either start listening to scientists or we start listening to corporations that care more about profit margins than they do our earth. The earth getting too warm may sound like california for people in Minnesota, but much of the planet will probably start seeing drought and dust bowls pop up.

    November 24, 2010 at 5:32 pm | Report abuse | Reply
  4. Condor

    If lakes warm and the algae grows rampant it can kill the lake and collapse the food chain

    That's serious the effects will be far reaching. Then when all the animals die including humans. There will be no more pollution and the earth will recover.

    Then the next time man appears on earth they will find the ruins and ask themselves; "what happened to this civilization?"

    Wow that's heavy stuff....don't want to think about it. Just keep pumping oil so I can drive my Hummer. HeHe

    November 24, 2010 at 10:16 pm | Report abuse | Reply
  5. Charlie

    No kidding!!! The entire planet has been warming for 15,000 years. And pretty soon we will see another Glacial period and all the lakes will be frozen again. DOPES!!

    November 25, 2010 at 1:04 am | Report abuse | Reply
  6. mememine69

    Taking into account the Bush family and their criminal wars, is it so unreasonable (considering voter support gone now), to suggest that the likes of Al Gore, the criminal lab coat consultants, pandering politicians, lazy teachers, criminal PR firms and most of all, the irresponsible NEWS EDITORS, all be round up and arrested and charged with treason for leading us to a false war of climate change? They condemned billions of people to death by CO2 for 24 years and we are supposed to just let them walk away now? Twenty-five years wasted on climate control instead of population control. Email your authorities in your particular part of the world and maybe, just maybe, history will not mock us all for this modern day witch burning of climate change. Meanwhile, the UN had allowed carbon trading to trump 3rd world fresh water relief, starvation rescue and 3rd world education. NOW tell us climate change wasn’t a crime!

    November 25, 2010 at 6:34 pm | Report abuse | Reply
  7. Irwandi

    So how many variables had been rptipsed out of the prediction model? Was the Sun's erratic behaviors not factored in the prediction? Was Geothermal and Geological activity assumed to be static? Was the fact the Solar System is about to enter into a section of the Milky Way that's rich in various cosmic radiation types ranging from Gamma rays to X-ray storms not factored in? Is Asteroid 2004 MN4 s gravity effects on the Earth geology as it passes by in 2029 ignored in this model? Is full out nuclear war between some form of Nation between another or a nuclear terror attack dismissed as a possiblity in their test group?Reply

    March 12, 2012 at 2:23 pm | Report abuse | Reply
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