EarthArt: What are you looking at?

By Tom Yulsman | February 19, 2013 8:40 am

It may look all the world like a work of abstract expressionism. But in reality, it’s a remote sensing image, created using data from a NASA satellite.

Can you figure out what this image shows, and why it is significant? As a bonus for true remote sensing geeks (like me), can you take a guess as to which satellite and sensor it comes from?

Leave your answers in the comments section. I’ll come back by the end of the day to declare a winner, and fill in the details where necessary.

MORE ABOUT: NASA, remote sensing
  • Gius Eppe

    thermic image of earth’s wind streams?
    I’m not a “satellite geek”, but it may be from a infrared scan?

  • Dan

    I’m going to guess temperature. You can see ocean currents across the center and bottom-right portions. Also, if you think where the Sahara, Outback, and American Southwest are, you’ll notice particularly high temperatures.

  • Kimberly Smeltzer

    I’m going to guess it’s the ocean conveyor belt?

  • Ron Broberg

    First Light: Beautiful image.

  • Tom Yulsman

    Dan is on the right track! Temperatures are indeed high where the Sahara, Australian outback, and American Southwest are. Now, let’s go a little deeper. What specifically is the satellite measuring? What accounts for the cooler and warmer areas? And why is this important? (Hint: This has to do with energy flows, the atmosphere, and climate.)

  • Austin

    Is this a solar flux density map? Areas like the Sahara and the American Southwest are targets for putting down solar panels because of their high solar flux density, not necessarily their high temperatures. They appear to be more intense on this map. Also, the rainforest areas of the globe are showing less intensity, signifying that the radiation is blocked by the canopies.

  • Mark

    Austin’s answer makes a lot of sense, but I can’t help but wonder about why the blue extends to such low latitudes in the northern hemisphere. It seems like the cut point from red to blue would have to be set pretty high (i.e. very high amount of flux for value to shift from blue to red) in order to have virtually all of ‘sunny’ California in the blue.

    The fact that there are such sharp edges to so much in the image makes me think that it’s an image produced over a fairly short period of time, perhaps even just an orbit or two.

    I also notice a very long sharp line on the left of the image running through the Pacific Ocean that runs mostly north-south but curves west as it moves north. There is a similar line running through southern Africa and also the Indian Ocean. These seem too sharp and straight to be natural (they’re not tectonic plate boundaries are they?), so my guess is that they could be artifacts of image processing. Could this tell us anything about the satellite’s orbit?

    I don’t see how we could be looking at ocean currents as has been suggested given that there are many places where these ‘currents’ move from ocean to land. So, my guess is that the blue is cloud cover over a short time period. Could the reds, then, be temperature (IR)?

  • Matthew James Balint

    heat index of the earth

  • Matthew James Balint

    definitely the heat index of the earth.



ImaGeo is a visual blog focusing on the intersection of imagery, imagination and Earth. It focuses on spectacular visuals related to the science of our planet, with an emphasis (although not an exclusive one) on the unfolding Anthropocene Epoch.

About Tom Yulsman

Tom Yulsman is Director of the Center for Environmental Journalism and a Professor of Journalism at the University of Colorado, Boulder. He also continues to work as a science and environmental journalist with more than 30 years of experience producing content for major publications. His work has appeared in the New York Times, Washington Post, Audubon, Climate Central, Columbia Journalism Review, Discover, Nieman Reports, and many other publications. He has held a variety of editorial positions over the years, including a stint as editor-in-chief of Earth magazine. Yulsman has written one book: Origins: the Quest for Our Cosmic Roots, published by the Institute of Physics in 2003.


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