An email to a friend / skeptic:

Oh boy. I can’t tell if this is a joke, but let’s just assume (gulp) that you actually do believe CO2 dissipates into outer space.

The latest data, as of March 2006, shows CO2 levels now stand at 381 parts per million (ppm) -- 100ppm above the pre-industrial average.

Look at this chart:



Do you see that line heading down at all? Over the last 40+ years, it’s been a steady upward climb, up almost 20%. But I thought CO2 was supposed to disappear into outer space? Looks like it’s instead just staying here and building up -– go figure!

Oh, and the right likes to say volcanic activity is responsible for all of this –- hogwash! Volcanic releases amount to just 1% of that which is released by human activities.

Since the start of the Industrial Revolution, the atmospheric CO2 concentration has increased by approximately 110 µL/L or about 40%, most of it released since 1945.

Finally, given the last 400,000 years (which includes the Ice Age), the denial folks like to say this current upswing is just part of a natural cycle as the past shows fluctuations in CO2 concentrations. HOWEVER, over those 400K years, CO2 has fluctuated between 200 and 300 parts per million --- never getting above 300. We’re now at 380 (again, see above chart). This time it is different!!