[CF-metadata] New standard name: angle between solar and sensor azimuth

From: Andreas Hilboll <lists>
Date: Mon, 17 Aug 2015 16:11:27 +0200

Hi all,

a common quantity in satellite remote sensing of atmospheric composition
is the so-called 'relative azimuth angle', which in that community
refers to the difference of solar azimuth and sensor azimuth. However,
relevant for the radiative transfer simulations is not the actual
difference solar_azim - sensor_azim, but rather

   raa = abs(solar_azim - sensor_azim) [where abs(solar_azim -
sensor_azim) < 180]
         360 - abs(solar_azim - sensor_azim) [otherwise]

I would like to propose this quantity to be included in the CF standard
names, but am unsure how to a) name it [*] and b) describe it [**].

Any ideas?

Cheers,
  Andreas.


[*] the 'relative_...' commonly used in satellite remote sensing of
trace gases seems to be un-fit for CF, because there

   relative_sensor_azimuth_angle is the difference between the viewing
   geometries from two different sensors over the same observation
   target. It is the difference between the values of two quantities
   with standard name sensor_azimuth_angle.

[**] I haven't yet seen formulas in the CF standard name definitions ...
Received on Mon Aug 17 2015 - 08:11:27 BST