Remote Sensing C

[AstroClarinet]

View the image at this link: https://eoimages.gsfc.nasa.gov/images/imagerecords/40000/40234/choiwan_cld_2009258.jpg

The image depicts Super Typhoon Choi-Wan. The top image was taken by MODIS on Aqua while the lower image shows data taken by a different A-train satellite.

1. Name the satellite and instrument which took the lower image. (Hint: it's one of the satellites with a focus on cloud profiling)
2. It is apparent from the lower image that whatever satellite took the image was able to collect data fairly deep into the clouds. If the other satellite with a focus on cloud profiling took the lower image, would it also be able to collect data from within the clouds, or would it only detect the very highest portions of the clouds? Why or why not?
3. Explain the effects of clouds on radiation coming from above (solar radiation) and radiation coming from below (infrared emitted from the ground) and the implications for Earth's overall energy balance.

[Zazou0621]

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You said "THREE. The A-Train    They are in a sun-synchronous orbit, an orbit where satellites exactly match the rotation of the earth and will always be in the light (or dark, if they are on the other side). A big advantage of this orbit is for optical passive sensors, that measure reflected sunlight, so that they can collect data at all times." 

This is blatantly wrong, sun-sync orbits operate so that the satellite crosses a point at the same time, solar time, every day. This is an important distinction as it is advantageous for satellites to cross the same point daily to get max illuminated images, or to fulfill other criteria, mostly having to do with light. Furthermore, if a sat was always in the dark it would need some alternative form of power, not solar panels, such as a nuclear plant, which doesn't exactly matter in the context of this competition but illustrates the characteristics of this orbit. You may have confused sun-sync with geostationary/geosynchronous, which match the rotation of the earth, essentially being able to hover or move very little over a point, but even those don't remain in light (sidebar, good album by the Talking Heads), nor do they remain in the darkness, they just match the point that they are over; a good example of geostationary is the GOES sats and a lot of communication/broadcast sats. I mean no ill intent towards you, just want to ensure the information is correct.

[RiverWalker88]

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You said "THREE. The A-Train    They are in a sun-synchronous orbit, an orbit where satellites exactly match the rotation of the earth and will always be in the light (or dark, if they are on the other side). A big advantage of this orbit is for optical passive sensors, that measure reflected sunlight, so that they can collect data at all times." 

This is blatantly wrong, sun-sync orbits operate so that the satellite crosses a point at the same time, solar time, every day. This is an important distinction as it is advantageous for satellites to cross the same point daily to get max illuminated images, or to fulfill other criteria, mostly having to do with light. Furthermore, if a sat was always in the dark it would need some alternative form of power, not solar panels, such as a nuclear plant, which doesn't exactly matter in the context of this competition but illustrates the characteristics of this orbit. You may have confused sun-sync with geostationary/geosynchronous, which match the rotation of the earth, essentially being able to hover or move very little over a point, but even those don't remain in light (sidebar, good album by the Talking Heads), nor do they remain in the darkness, they just match the point that they are over; a good example of geostationary is the GOES sats and a lot of communication/broadcast sats. I mean no ill intent towards you, just want to ensure the information is correct.

Thanks for catching that--I'll link your correction in my reply. It's always good to make sure the information on the site is correct! It took me quite a while to start understanding orbits this year.