Slide 26: Greenhouse gases: others
There are a number of other greenhouse gases that we till touch upon briefly. Ozone plays an important role in reducing shortwave radiation influx by absorbing primarily ultraviolet light in the upper atmosphere, using the energy to spontaneously break up and re-form (Chapman, 1930). However, in the lower atmosphere ozone is a pollutant and a greenhouse gas
The catalytic action of nitrous oxides, halocarbons and hydroxl ions (OH-) in the stratosphere catalytically destroys large quantities of ozone, thereby increasing solar radiation. As well as increasing the rate of global warming, this action has the effect of increasing the incidence of shortwave radiation-induced mutations in many forms of life.
Halocarbons (CFCs and HCFCs), apart from destroying ozone in the upper atmosphere, are very strong greenhouse gases (thousands of times stronger than CO2) (IPCC, 1990). Furthermore, they are highly stable, taking decades to centuries to break down.
These gases are entirely manufactured. They are primarily used as propellants for deodorants and other spray cans, and in refrigeration and air-conditioners. As such, their effect has only been observed in the last century, with a climatic forcing rising from nothing in 1900 to 0.202 Wm-2 in 1990.
Chapman, S., 1930. A theory of upper atmospheric ozone. Quar. J. Royal Met. Soc., 3, pp. 103.
Intergovernmental Panel on Climate Change (IPCC), 1990. Climate Change: The IPCC Scientific Assessment, Houghton, J.T., Jenkins, G.J. & Ephraums, J.J. (eds.). Cambridge University Press, Cambridge, 365pp.