In 2006, NASA knew that Antarctic temperatures had “decreased significantly” in recent decades.

Antarctic Temperature Trend 1982-2004 : Image of the Day
Shindell, D.T., and G.A. Schmidt 2004. Southern Hemisphere climate response to ozone changes and greenhouse gas increases. Geophys. Res. Lett. 31, L18209, doi:10.1029/2004GL020724.
While most of the Earth warmed rapidly during recent decades,surface temperatures decreased significantly over most of Antarctica.
Pubs.GISS: Abstract of Shindell and Schmidt 2004
This cooling trend was confirmed by a steady increase in sea ice surrounding the continent.

iphone.anomaly.antarctic.png (512×412)
Satellites also show a cooling trend over the oceans surrounding Antarctica.

RSS / MSU Data Images / Monthly
But this cooling didn’t suit the global warming agenda, so in 2007 NASA simply made the cooling disappear.
Disintegration: Antarctic Warming Claims Another Ice Shelf : Feature Articles
They used this completely implausible excuse for their data tampering
This image was first published on April 27, 2006, and it was based on data from 1981-2004. A more recent version was published on November 21, 2007. The new version extended the data range through 2007, and was based on a revised analysis that included better inter-calibration among all the satellite records that are part of the time series.
In other words, they are criminals committing fraud for political and funding purposes.