Variability of the Earth’s climate - Ice Ages and Interglacials: Measurements, Interpretation, and Models - page 32

Figure 2.4. Range of CO 2 concentration (280-560 ppm) for 21st century climate change (gray
slice).
Figure 2.5. Variation of T G with CO 2 concentration.
industrial climate (T G 14.3 C and CO 2 280 ppm) and allow the CO 2 concen-
tration to increase with no other changes to the Earth, we can calculate the
additional absorption of upward IR radiation emitted by the Earth due to
increased CO 2 concentration, and thereby estimate from the laws of radiant heat
transfer, how much the Earth needs to warm in order to establish a new equilib-
rium whereby incident heat input from the Sun is counterbalanced by heat
radiated by the Earth to space. This calculation has been carried out, and it is
widely accepted that if feedbacks are neglected an increase in CO 2 concentration