Fluorocarbon refrigerants impact the environment in two main ways: ozone layer depletion and global warming.
Destruction of the ozone layer allows more harmful ultraviolet rays to reach the Earth's surface, resulting in the increase of skin cancer and other problems.
The ozone depletion potential (ODP) is the ratio of the potential impact on ozone of a chemical compared to the impact of the same mass of CFC-12, with the latter having an impact of 1.
|CFCs||Since CFCs contain no hydrogen in molecules, they are stable in the atmosphere. This means they cannot be easily broken down until they reach the stratosphere and thus have a high ODP.|
|HCFCs||Since they contain hydrogen in molecules, HCFCs can be broken down relatively easily in the atmosphere and thus have a low ODP.|
|HFCs||Since they contain no chlorine or bromine, HFCs have an ODP of zero.|
Global warming refers to a phenomenon in which infrared rays are absorbed by molecules in CO2 and methane, as well as air conditioner refrigerants like CFCs, HCFCs, and HFCs. This prevents heat from escaping the Earth's surface.
The Earth radiates infrared rays from being warmed by the sun's rays in the daytime.
These infrared rays should be absorbed in outer space, but before they get there they are instead absorbed within the Earth's atmosphere.
The Earth's surface gets warmer.
|:Substances covered by the Kyoto Protocol|
|Global warming substances||Atmospheric life||GWP (global warming potential)
* From IPCC Fourth Assessment Report.
The Kyoto Protocol uses GWP from the Second Assessment Report of the IPCC.