Exiftool is a very easy to use, complete, command-line interface to image EXIF data. It also (and especially) works with GPS data and tiff files.
For instance, to view the filename, size and latitude of an image:
exiftool -filename -imagesize -gps:GPSLatitude IMGP0737.tif
To set the new latitude of an image:
exiftool -gps:GPSLatitude="52 deg 47' 22.5894" IMGP0737.tif
I read the Exif 2.2 spec (ya know, light reading), and realized that I was formatting the GPS info tag incorrectly. Exiftool formats the correct version to look pretty (and as above). However, the official spec states that the latitude and longitude info should be dd,mm,ss or dd,mmmm and then the North/South and East/West specified in the GPSLatitudeRef and GPSLongitudeRef as N/S, or E/W. Therefore, the correct format is:
exiftool -GPSMapDatum="WGS-84" -gps:GPSLatitude="34,57,57" -gps:GPSLatitudeRef="N" -gps:GPSLongitude="83,17,59" -gps:GPSLongitudeRef="W" -gps:GPSAltitudeRef="0" -GPSAltitude=1426 -gps:GPSMeasureMode=2 -City="RabunBald" -State="North Carolina" -Country="USA" ~/Desktop/RabunBaldSummit_NC.jpg