Natural and anthropogenic substances and processes that alter the earth's energy budget are drivers of climate change.
Radiative forcing quantifies the change in energy fluxs caused by changes in these drivers for 2011 relative to 1750, unless otherwise indicated
Positive RF leads to surface warming. Negative RF leads to surface cooling.
RF is estimated based on in-situ and remote observations, properties of greenhouse gases and aerosols, and calculation using numerical models representing observed processes.
Some emitted compounds affect the atmospheric concentration of other substances.
The RF can be reported based on the concentration changes of each substance.
Alternatively, the emission-based RF of the compound can be reported, which provides a more direct link to human activities.
It includes contributions from all substances affected by that emission
The total anthropogenic RF of two approaches are identical when considering all drivers.
Though both approaches are used in this summary for policymakers, emission-based RFs are emphasized
Total radiation forcing is positive, and hes led to an uptake of energy by the climate system. The largest contribution to total radiation forcing is caused by the increase in the atmospheric concentration of co2