4 ms·
The refraction doesn't matter, its the precision. Given a reading (of 02 ppm), how can you prove that it matches the reading a ground station would have made?
by falsedan 9y ago
The refraction doesn't matter, its the precision. Given a reading (of 02 ppm), how can you prove that it matches the reading a ground station would have made?
How could you filter out the noise from materials in the ~100km of atmosphere between the satellites and the targets? More pragmatically, could you explain it in a courtroom & convince the jury that it works?
I understand that you're disappointed that this extremely useful idea doesn't have a simple solution.
- m_mueller 9y agoNah, I'm not disappointed, just trying to understand the limits of current sensors. I also don't think it needs to be extremely accurate - maybe there's even proxies that could be used, like the shade of green on cloudless days for land coordinates, however this opens up a lot of abusive avenues of course. Btw. how about something like OCO-2? I couldn't find anything about its spatial resolution, but it seems to allow ground measurements of carbon sinks and sources. https://oco.jpl.nasa.gov/science/MeasurementApproach/ https://oco.jpl.nasa.gov/science/MeasurementApproach/ https://en.wikipedia.org/wiki/Orbiting_Carbon_Observatory_2 https://en.wikipedia.org/wiki/Orbiting_Carbon_Observatory_2
- falsedan 9y agoIts spacial resolution is on the linked page: > OCO-2 records how much sunlight is reflected off the CO 2 molecules in an air column. OCO-2 makes measurements in three different spectral bands over four to eight different footprints of approximately 1.29 km × 2.25 km (0.80 mi × 1.40 mi) each. It's air columns, so again you would have a hard time proving that the source of the detected pollutants came from the area & excluding the case that they drifted into the area at a higher altitude.