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I must work with a projection, in order to execute the intended geometric operations. I'm looking for a projection that could cover an area of up to 200km X 200km. I'm aware of some local projections, but I don't have an EPSG for them.

The ideal solution to me would be a UTM projection centered in my region of study, but I don't have an EPSG for it.

I'm working in Python (GDAL library). The program is intended to be used everywhere in the globe (Possibly not the polar region)

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    It depends on the GIS software (which you haven't specified) and the geographic region (which you haven't specified) and the other potential projections (which you haven't specified), but generally a custom or local projection is possible. Commented Feb 7, 2021 at 13:21
  • software: GDAL library or QGIS. Region: no specific region. Anywhere between +60to -60° latitude. Commented Feb 7, 2021 at 14:11
  • See gis.stackexchange.com/questions/360024/… for converting longitude to UTM zone to EPSG. Commented Feb 7, 2021 at 14:48
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    I had similar issues. If you need a projected coordinate system you always get problems when your're far away from your central meridian. If it's possible try to split your research area and choose an ideal coordinate system for each partial area. Commented Feb 7, 2021 at 15:34
  • It's possible to calculate a WGS 84-based UTM zone's EPSG code/well-known ID. 326 + zone number if N of equator, 327 + zone number if S of equator. I know there's a question or two here about calculating a UTM zone number based on a longitude value. Commented Feb 16, 2021 at 21:43

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You can use define your own custom Transverse Mercator Projection. Many Geospatial libraries including GDAL will take a PROJ string as well as an EPSG code to define a projection. Here is an example. I want to map an area in central Yemen along 48 degrees longitude, which is between two UTM zones. Therefore I will use this Proj string: "+proj=tmerc +lon_0=48 +x_0=500000 +k=0.9996"

I have also specified a false easting of 500,000 meters and a scale factor of .9996 similar to UTM projections.

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