Cloud reflectivity modification
Cloud Reflectivity Modification is also known as cloud whitening, cloud reflectivity modification is an excellent example of a geo-engineering approach to curb and slow down the effects of global warming. The reflectivity of clouds is either increased or decreased to alter their climatic effect. Two forms of cloud whitening have been proposed; marine cloud brightening and cirrus stripping.
Cirrus stripping is the thinning or total removal of cirrus clouds from the earth’s atmosphere. Cirrus clouds reflect a high amount of infra-red from the earth’s surface and simultaneously allow a high percentage of sun rays to reach earth. All this heat raises the earth’s temperature. If cirrus clouds were to be thinned or removed, a lot less infra-red would be reflected and this would effectively cool the earth.
Marine cloud brightening on the other hand involves the seeding of low stratocumulus clouds with high amounts of water particles preferably from the sea in order to increase the water particle concentration in the low clouds. This will make the clouds more reflective to the sun rays that reach the earth’s surface hence decreasing its temperature.
Effective cloud reflectivity modification will alter the earth’s albedo. The resulting effects of this project are expected to fully reverse the effects of global warming. It is an added advantage that the cloud condensation nuclei naturally precipitate.
The benefits of cloud reflectivity modification are that it can be carried out at a particular location where it is most required. This also prevents ecological problems. It also utilizes natural resources which can be reused such as the wind and sea water. Use of these natural resources and utilization of pre-existing technology makes cloud reflectivity modification cheaper than other geo-engineering approaches to climate change.
The problems that this global scale project encounters include the unpredictable wind patterns which this idea fully depends on. The effects of greenhouse emissions on marine cloud brightening have also not been fully researched. The use of airplanes and turbo-powered ships to disperse water particles is cumbersome and time consuming and their continued use results in large emissions of carbon particles. Cloud reflectivity modification also does not address the problem of ocean acidification.
Cloud reflectivity modification is an excellent geo-engineering approach to climate change which if well utilized will produce excellent results which will go a long way in prolonging the life span of earth and its subject.
Reference
Twomey, S.(1997), “The influence of Pollution on the Shortwave of Abeldo of Clouds.
S. E. Schwartz, A. Slingo In: P. Crutzen,(1996) Editor, Clouds, Chemistry and Climate: Proceeding of NATO advanced Research Workshop.
Latham, & Salter (2005). Preventing Global Warming by Preventing Cloud.
