Can a reprojection/change of CRS operation be done lazily using rioXarray?

I think they can be unified. From what I can tell by reading these threads and the github, GeoZarr is not set in stone but I think we can figure it out. This is a good thread on some of the challenges

Showing some prototype implementations that can be iterated on and discussed seems like the current next step.

  1. lazily reading in many raster images into the same Xarray object without materializing coordinates. The feature in Xarray to enable this has been drafted here: Flexible coordinate transform by benbovy · Pull Request #9543 · pydata/xarray · GitHub

  2. roundtripping the CRS data after writing the GeoZarr and reading back to the original Xarray object seems like the next step. This round tripping demonstration has been discussed in a few places or even implemented but not in a generic way within xarray or it’s extensions.

This approach for ironing out the spec has been brought up in a couple threads and I think it’s a good one. It seems like what’s a limiting factor is people power to provide implementations that can be discussed and iterated on.

I saw that November 6th there is a meeting to discuss the GeoZarr spec: GeoZarr Spec Steering Working Group - HackMD. I’ll attend, hope to see many others! I’d like to contribute to protoyping GeoZarr. As a first step I am working with a very sparse 2Gb dataset of Sentinel-2 raster chips across Europe, Eurosat, and trying to make a prototype that addresses points 1. and 2. above.

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