stilt.observations.read_tropomi_ch4#

stilt.observations.read_tropomi_ch4(path, *, lon_range=None, lat_range=None)[source]#

Read a TROPOMI (Sentinel-5P) L2 methane file into a table of soundings.

Reads the operational S5P_*_L2__CH4___ orbit files and the TROPOMI+GOSAT blended files (S5P_BLND_L2__CH4___).

Parameters:

  • path (str | Path) – The product file.

  • lon_range (tuple[float, float] | None) – (min, max) longitude and latitude, in degrees. Only pixels inside the box are read, which saves time on a whole orbit.

  • lat_range (tuple[float, float] | None) – (min, max) longitude and latitude, in degrees. Only pixels inside the box are read, which saves time on a whole orbit.

Returns:

One row per pixel. value is the bias-corrected XCH4, or the blended XCH4 in a blended file, in ppb. good is qa_value >= 0.5, as the product recommends. The pressure grid is rebuilt from surface_pressure and pressure_interval. pressure_levels are the 13 layer boundaries from the surface up, the top one at 0 hPa, and ak_pressure the 12 layer midpoints that go with ak. altitude_levels are the product’s heights of those boundaries, to use for a slant path. apriori is the prior profile as a mole fraction per layer, in ppb. zenith and azimuth are the viewing angles toward the satellite. Blended files have no viewing angles and no altitude_levels.

Return type:

DataFrame