1.2 Advantages
Advantages of reducing global warming by covering large tracts of desert with white plastic can be summarized as follows:
(1) The cover can be dispersed to take advantage of terrain. It need not be continuous or all in the same general area, since the total surface area covered defines the impact on re-radiated infrared radiation.
(2) The cost is relatively low ($15/metric ton carbon equivalent) compared to presently proposed countermeasures such as implementing fuel cell technology or capture and sequestration of carbon emissions from power plants.
(3) The technology to produce the plastic cover already exists.
(4) The plastic cover’s effectiveness can be easily monitored by surface instrumentation, aircraft over flights and satellites. The technology for each of these is well developed and readily available.
(5) Wind field capacity may be generated or enhanced in the low temperature zone created by the covered areas, thereby creating a wind generated energy source that could be used locally to provide power for the GAEP. Wind turbine projects are already underway in the Mojave desert that seek to take advantage of existing wind fields (1).
(6) An added benefit of reducing mean global atmospheric temperatures is to reduce the demand for electricity for air conditioning, thereby reducing GHG emissions from power plants. In cities that may be close to the coverage, e.g., Las Vegas or Phoenix, the effects may be more noticeable and the decrease in demand much greater.
(7) Cooling the southwestern Sahara may reduce the number of tropical waves that enter the Atlantic and thus, the number of Atlantic hurricanes. This would be a result of slower evaporation rates for precipitation falling in the covered areas of the Sahara. There is limited evidence that future warming in this region will increase water vapor levels and lead to anincreased number of these waves (2). It is these easterly waves that account for 85% of the most intense Atlantic hurricanes (3), some of which have made landfall and caused extensive damage and loss of life.
(8) Even if large-scale surface albedo enhancement is determined to be undesirable due to effects on regional or global climate, smaller-scale enhancement could still be done to offset emissions from individual industries or countries. As an example, every square mile covered offsets the equivalent in radiative forcing of the carbon dioxide emissions from 7000 SUVs taken over a 15-year life cycle. Likewise, the equivalent in forcing from one 350 MW power plant with a lifetime of 35 years can be offset for every 12 square miles covered (Appendix A).
(9) How land use changes contribute to regional and global climate change can be studied.(10) Knowledge can be gained about terraforming that may be applicable later in interplanetary space exploration.
(11) Knowledge can also be gained that may aid in learning how to mitigate dust storms on earth.
