The Atmosphere and Climate Modeling - Introduction to Carbon Capture and Sequestration - page 58

Figure 2.3.4 Radiative forcing
Summary of the principal components of the radiative forcing of climate change. All
these radiative forcings are associated with human activities or natural processes. The
values represent the forcings in 2005 relative to the start of the industrial era (about
1750). Human activities cause signifi cant changes in long-lived gasses, ozone, water
vapor, surface albedo, aerosols, and contrails. The only increase in natural forcing of any
signifi cance between 1750 and 2005 occurred in solar irradiance. Positive forcings lead
to warming of the climate and negative forcings lead to a cooling. The thin black line
attached to each colored bar represents the range of uncertainty for the respective
value. Figure from IPCC, reproduced with permission [2.2].
as the measured rate of energy change per unit area (in W/m 2 ) of the globe.
A positive value increases the temperature of the earth. Figure 2.3.4 com-
pares the radiative forcings of various human activities [2.2]. As we can
see, not all human activities increase global temperature. For example,