Wrong hemisphere in geotiffs EPSG code for HLS data

[amigdala999]

Hi,
I wonder if it's a bug.
I'm downloading a tile 50HLG which according to MGRS is in south hemisphere. It's in Australia or near it.

wget -v https://data.lpdaac.earthdatacloud.nasa.gov/lp-prod-protected/HLSS30.020/HLS.S30.T50HLG.2025080T021209.v2.0/HLS.S30.T50HLG.2025080T021209.v2.0.B08.tif

The I'm looking in its SRS data with:

gdalsrsinfo HLS.S30.T50HLG.2025080T021209.v2.0.B08.tif

and it outputs:

PROJ.4 : +proj=utm +zone=50 +datum=WGS84 +units=m +no_defs

OGC WKT2:2019 :
PROJCRS["WGS 84 / UTM zone 50N",
<.......>
AREA["Between 114°E and 120°E, northern hemisphere between equator and 84°N, onshore and offshore. Brunei. China. Hong Kong. Indonesia. Malaysia - East Malaysia - Sarawak. Mongolia. Philippines. Russian Federation. Taiwan."],
BBOX[0,114,84,120]],
ID["EPSG",32650]]


It has EPSG 32650 while I would expect 32750 and 50S in this file.
This affects all (at least S30) data in southern hemisphere.

Is this a bug or by design?

[amigdala999]

Additionally tiffinfo prints mismatching details:

$ tiffinfo HLS.S30.T50HLG.2025080T021209.v2.0.B08.tif
....
Tag 34737: UTM Zone 50, Northern Hemisphere|WGS 84|
GDAL Metadata: <GDALMetadata>
...
<Item name="HORIZONTAL_CS_CODE">EPSG:32750</Item>
<Item name="HORIZONTAL_CS_NAME">WGS84 / UTM zone 50S</Item>
....

[LP DAAC - lien]

Hello,
Thanks for bringing this to our attention. We are looking into this, and as soon as I have more information, I will let you know.
Brett

[amigdala999]

Hi, any news regarding this?
It seems this could cause 'ERROR: transform: Point outside of projection domain (2050) ' errors when processing such GeoTiffs with latest PostGIS. Im considering to reprojecting all files to SRID 4326

[LP DAAC - dgolon]

Hello @amigdala999 Please see this response from the HLS Science Team:

HLS uses the convention of keeping the UTM Y coordinate in the Southern Hemisphere negative, i.e., with a false northing value 0, without adding 107 to make the coordinate positive. This way, the Y coordinate alone indicates the associated hemisphere, with no need for an explicit specification. A location is unambiguously determined with the UTM Zone and X,Y coordinate information. However, the software API used to set the HLS map projection metadata requires an explicit hemisphere specification for the Southern Hemisphere, but the HLS code fails to supply; as a result, all tiles are labeled as in the Northern Hemisphere by default. Most of the GIS and image processing packages can use the available information without error, although the metadata query shows the wrong EPSG code for a UTM zone for the Southern Hemisphere.