Greenpeace: The levels of the carbon dioxide in the atmosphere has reached 400 parts per million for the first time in human history. The last time levels were this high global average temperatures eventually reached 3 or 4C° higher than now, the polar regions were up to 10C° warmer than today the Greenland and Antarctic ice sheets were smaller and Sea level ranged between five and 40 meters (16 to 131 feet) higher than today.
There are two reasons to be seriously worried by this year's CO2 measurements...