Why do Landsat scenes in the Southern Hemisphere display negative UTM values?

Traditional Universal Transverse Mercator (UTM) convention distinguishes between the Northern and Southern Hemispheres. In the Northern Hemisphere, the UTM zone is a positive value or identified as UTM North. In the Southern Hemisphere, the UTM zone is a negative value or identified as UTM South. UTM North scenes in this convention have a false northing value of 0, while UTM South scenes have a false northing of 10,000,000. This false northing value effectively shifts the negative projection Y coordinates to a positive value.

Landsat Level-1 data products are processed to a northern (positive) Universal Transverse Mercator (UTM) projection zone, regardless of whether the scene is in the Northern or Southern Hemisphere. Because of this, any scene in the Southern Hemisphere will have a negative projection Y coordinate.  Processing all Landsat scenes to the northern zone helps correct a discontinuity when scenes are being mosaicked. 

The scenes will display correctly in most (if not all) popular imaging software packages; however, simply negating the UTM zone or reassigning the UTM North to UTM South will cause the projection coordinates to be inaccurate. If the UTM zone is switched to a southern zone for a Southern Hemisphere scene, then the projection Y values must also be adjusted by a value of 10,000,000. This will ensure any coordinate transformations are handled correctly.