I have put this link in the sidebar link list, but its worth showing you what it does.
The chart gives a monthly update of the CO2 levels at Mauna Loa - probably the most iconic (and certainly the longest running) CO2 monitoring site.
Chart: CO2 level at Mauna Loa. Data up to February 2010.
As you see there are seasonal variations (due mainly to plant growth during the northern hemisphere summer absorbing more CO2), so the 'middle' line in the chart is the level with the seasonal variation removed.
Make a note in your calendar to check this each month.
I've been watching this for a while, and in spite of all the cries of denial and hope we haven't made the overall trend line turn downwards yet.
Until we do; (you know what I'm going to say don't you) the ice is going to continue to melt and the seas will continue to rise until all the ice is gone.