Earthdata Forum

Hello!

For the satellite products of water vapour and aerosol optical thickness at 550 nm (AOT_550) data, is there any way to convert them to the data at the airborne altitude which is about 2 km?

Thank you in advance.
Kind regards,
Mengmeng.

Mengmeng,

For aerosol optical depth, because it is a cumulative measure of light absorption / scattering in the atmosphere, there is not a value at a specific altitude. For water vapor, the Atmospheric Infrared Sounder (AIRS) provides data at specific pressure levels (hPA); these pressure levels can be used as approximate altitude in the atmosphere. MERRA-2 does not have a water vapor data variable, but does have relative and specific humidity data at different pressure levels. If you use the Giovanni search link below, and then examine the righthand column, titled "Vert. Slice" ("Vert." for "Vertical") any variables with a dropdown menu box for pressure level selection provide data at different pressure levels.

https://giovanni.gsfc.nasa.gov/giovanni ... 20Model%3B

You do not need to use Giovanni to get these data; this will just indicate what variables have data at different pressure levels. Please reply for further clarification.

Hi jimacker,

Thank you very much for your reply. I got it.

Kind regards,
Mengmeng.