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Yeah, I think that the cell with the closest centroid is not always the cell that contains the point of interest. Previously, in a project in which I was using TROPOMI observations, I was constructing a polygon mesh for each file and using point-in-polygon, with only minor optimizations. It was real...

That appears to read in an array well enough (which in R can be done with the `ncdf4` package), but without any geometry. I'm looking for a way to get values corresponding to points on land, such as longitude -73.953626, latitude 40.789693.

I've been looking at the recently released TEMPO_O3PROF_L2_V04 product. Given a NetCDF file (such as TEMPO_O3PROF_L2_V04_20250921T210803Z_S012G02.nc) and some points, I'd like to get the ozone values (`/product/ozone_profile`) from the bottom layer (layer 24) for the given points. Do you have any su...

The full product name is "MODIS/Aqua Vegetation Indices Monthly L3 Global 1km SIN Grid V061". Consider the search https://search.earthdata.nasa.gov/search/granules?p=C2327957988-LPCLOUD&&pg[0][qt]=2023-12-01T00%3A00%3A00.000Z%2C2024-02-01T23%3A59%3A59.999Z&pg[0][id]=*h08v04* I ...

Thank you, I think that file will do nicely. It seems to define the geometry in 3D rather than 2D, which is probably a mistake, but I don't think that will be hard to work around.

I'm not sure what you're asking. If you're asking what research project I'm involved in, I'm a biostatistician at the Icahn School of Medicine at Mount Sinai, working on a non-NASA study of matching up satellite products like MCD19A2 with independent data sources. If you're asking about MCD19A2, it'...

Say I want to figure out which tiles in the scheme used by MCD19A2 collection 6 (identified with names like "h10v04") are necessary to cover some region of interest (such as the contiguous United States). What's the recommended way to do that? An official shapefile for the tiles would be h...

With MOD11 data from OPeNDAP, and with MOD21A1D HDF files from EarthData Search, I've been able to interpret values of the `QC` variable with bitwise operations and the appropriate user guide. In these cases, `QC` is provided as integers. But in the case of MOD21A1D data from OPeNDAP, `QC` is given ...

For posterity, here was how I ended up handling this. Luke Oman of NASA/GSFC kindly pointed me to a command-line program, `ncks`, that can retrieve a netCDF file from an OPeNDAP server, even one that doesn't seem to produce netCDF otherwise, so I guess `ncks` processes the DODS internally. Instead o...

Thanks. I've dropped them a line.