According to a press release, the oldest DNA ever recovered indicates that a boreal forest once covered Greenland during the last Ice Age:
The DNA samples suggest the temperature of the southern Greenland boreal forests 450,000 to 900,000 years-ago was probably between 10C in summer and -17C in winter. Also, the reduced glacier cover in that region means the global ocean was probably between one and two metres higher during that time compared to current levels.
Now, how many politicians who deny or obfuscate on global warming do you think also deny evolution? (Let's see, Tanceredo comes to mind... anyone else got examples with citations?). They go together like, um, Adam and Eve? Tobacco and oil? Anyway, a politician who denies evolution is bound to be a young Earth creationist, and no doubt they'll be itching to use this data to say that if Greenland was warmer than we once thought, then we can't be sure of the causes of recent global warming.
But then they have to deny the big part of this evidence. Note the dates of the DNA -- 450,000 to 900,000 years ago! Why, that was before the Earth was even created!
Of course, denying obvious facts, cherry-picking what they want, and the use of the biggest creationist tactic -- fingers in the ears, "la la la I can't hear you" -- are pretty standard fare.