In July, I mentioned Project GLOBE, which was pushing for one million observations matched to satellite overflights.
Disclosure: I uploaded a dozen or so observations myself, which I assume were counted in this million.
As I discussed earlier, this program has been going for a long time now. The idea is to augment satellite and other observations with “ground truth”—observations from the ground. The most useful observations would be at the same time as the satellite is overhead, i.e., the same sky from multiple angles.
This is actually quite easy to do with a smart phone app. The app grabs your position with GPS, and then loads data for when NASA’s satellites will be overhead. When it’s time to make a report, you get a reminder, ding! You fill in some questions about what kind and how many clouds are visible. Optionally, you can take a montage of photos with your phone. And then everything is uploaded to GLOBE, where it is added to the database. It’s Science, man!
Now, I admit that I’m not necessarily a perfect observer. Honestly, I’m not very sure I can tell high level, medium, or low clouds apart. And my estimates of “percent coverage” are probably iffy. Basically, the “partly cloudy” stuff is harder. I’ll note that I did try to report observations when it is very clear or very overcast, which are easier to get right.
So—is this iffy data really going to help?
Well, Data Sensei Nate Silver is known to say that more data is better than less data. I doubt that NASA takes these observations as 100% accurate, they surely include some kind of uncertainty in any statistics or models that use them. But the thing is, a million partially correct observations is a lot of good data.
So no, this is not just a PR exercise to make me and thousands of school kids feel good. This data is actually useful.
In fact, its even more useful because the observations come from all over the planet, not just where NASA scientists live. Dozens or hundreds of data points from, say, Nigeria, are really valuable if there are relatively few “professional” observations.
So–well done all [pats own back : – ) ]!
I’ll note that Project GLOBE is also trying to collect ground truth data on trees and land cover. It’s the same app, though I haven’t tried these options. (My initial examination indicates that these observations are trickier than just looking at and photographing clouds.)
So, get the app, and try it out!
- Joe Atkinson, NASA Cloud Observation Program Nets a Million Satellite Matches, in NASA Langley – News, August 1, 2022. https://www.nasa.gov/feature/nasa-cloud-observation-program-nets-a-million-satellite-matches
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