CORRECTIONS MADE TO SURFACE FILES IN EARLY 2007: Corrected versions were ftp'ed to AMRC.

.SRF files from 1991-1994: QC was done by comparing .SRF files to scanned files of original observation forms. Various corrections were made, mostly filling in remarks that were missing from the .SRF files. Values that had been recorded incorrectly were corrected when it was obvious what the correct value was. 

2006 .lcd, .mgr and F-6 monthly files: Various minor corrections were made, mostly to ensure consistency between files for a given month. For instance, the February average temperature of -42.6C was correct on the F-6 but had been listed as -42.7C on the .lcd and .mgr files. 

2005 and 2006 .sfc files: The .sfc files were corrected to include surface and horizon definition remarks during the flight season. These had been missing since the database entry form was changed in late November 2005.  Also, both the .sfc and .hrl files had been limited to 3 cloud layers. The code was changed to widen the sky cover column and include 4th layers when reported. Files were re-created when necessary back through February 2005. Due to database format changes, earlier months could not be successfully re-created and so were not changed. However, the frequency of 4th cloud layers being reported is very low and the omission of such layers in earlier files will not have a significant impact on the dataset. The most consistent source for cloud cover amount is the six-hourly synoptic observations that are archived in monthly .syn files.