Earthdata Forum

This wind data M2TMNXFLX_v5.12.4 -- Northward surface stress the values positive is north wind or south wind? I am looking for information here https://disc.gsfc.nasa.gov/information/glossary?keywords=giovanni%20measurements&title=Giovanni%20Measurement%20Definitions:%20Wind; but I not found.

Yes. Positive is north wind.

To clarify, I meant the northward direction is positive, i.e., positive value when the wind blows from south to north.

TAUY is defined as the northward stress in the File Specification Document, So TAUY is positive northward. You can find the File Specification Document, and many other useful documents here: https://gmao.gsfc.nasa.gov/reanalysis/MERRA-2/docs/

So, it's a south wind — that means the wind is blowing from the south to the north. It's a bit confusing, since we know that wind is named after the direction it comes from, like a northerly wind. So, 'northward' means 'toward the north,' which in the case of wind would be caused by a south wind. So, positive values is south wind and negative is north wind?

This is relative to the models coordinate system and the vector components of the wind. If you compare VLML with TAUY, you will find them positively correlated. The meridional component (V wind) is positive to the north, and the TAUY is also positive for positive V near the surface. It comes down to the models vector wind sign convention. I hope that helps.