by Eric Grimsrud

In my first Post called “1.  A Common Sense View of AGW”,  I presented a simple qualitative view of the AGW problem in order to relate the essence of what the debate is primarily about.  In this Post 6, we will move on to consider some basic quantitative aspects of AGW.  In this section, we will be searching, in particular, for good expressions for what’s called the temperature “Sensitivity” for CO2.  That number indicates the increase in average global temperature that would be caused by a doubling of its concentration.  To better appreciate the immediate importance of this number, recall this. Atmospheric CO2 was at 280 prior to the Industrial Revolution.  It is now 392 and rising at a rate of 2 ppm per year.  Therefore, a “business as usual” course will lead to a doubling CO2 within the current century (by about 2094). Continue reading →