Ice loss in the Antarctic; the truth, not "warmist" propaganda

The Register reports that:

"Scientists using a network of ground sensors emplaced in Antarctica say that NASA satellites have overestimated the amount of ice that is melting and running off into the ocean from the polar continent.

...

The WAGN boffins say they are sure that recent figures for ice loss calculated from GRACE readings have been overestimated, but they are not yet sure by how much. However, they say that there is no dispute about the fact that ice is disappearing from the antarctic sheet - this process has been underway for 20,000 years, since the thickness peaked during the last "glacial maximum".

"The published results are very important because they provide precise, ground-truth GPS observations of the actual rebound of the continent," said Vladimir Papitashvili of the Antarctic Earth Sciences Program at the National Science Foundation, which supported the research."

So ice levels are decreasing but that's compared to the 20,000 year ago "glacial maximum". I don't understand how that can be because I keep being told that man is to blamd for global warming via the pumping out of CO2 and yet the world was warming 19,850 odd years before man started producing CO2 in any major way. How can that be?