1.3 Disadvantages
Disadvantages can be summarized thusly:
(1) The use of the plastic cover removes the land from other uses for possibly hundreds of years, since it takes up to 200 hundred years for carbon dioxide emitted today to be removed from the atmosphere by natural processes (4). Premature removal of the cover will allow the same radiative forcing effects to occur almost instantaneously that would have had the cover never been applied and in proportion to the amount of forcing offset. The actual length of time that the coverage will need to be in place will be determined by advances in energy technology. Ideally, the coverage might only need remain in place through the middle of the next century, 2160.
(2) Although the initial intallation cost is low, the requirement to keep the cover in place for more than a century and replace it periodically, will include a recurring cost component that will keep adding to the overall cost until the covering is no longer needed.
(3) The cover will kill all plant and animal species in the covered areas.
(4) Some of the countries of the target areas are politically unstable or may not be agreeable to this use of their land. However, many of these countries are also impoverished and debt ridden and if debt forgiveness was substituted for payments they would receive for use of their land, many would probably agree to participate.
(5) The plastic cover will require significant maintenance to keep the surface reflective to solar radiation to maintain the high albedo. This will be especially difficult in desert regions. A 150-year maintenance period may sound unreasonable, but many buildings and other structures that are maintained are more than 150 years old and the U.S. DOE’s Yucca Mountain and Carlsbad facilities for high-level nuclear waste disposal are designed to last 10,000 years. A more relevant example is the U.S. interstate highway system, now nearly 50 years old. Also, this is not fundamentally different than guaranteeing the growth of part a forest for 75-100 years as is now being done on a small scale by certain companies intending to use the carbon stored to offset their GHG emissions or the annual planting of thousands of square miles with grains or other crops.
(6) There may be negative local, regional and global climate changes resulting from the covering, which are of an unforeseen nature or of a predictable nature. For example, areas inside the covered zone may experience much colder and drier weather, due to subsidence heating, expanding the desert andexacerbating conditions in the arid lands bordering the deserts, e.g. the Sahel region south of the Sahara. Covering large tracts of desert may also alter dust flow patterns and quantities, affecting nutrient loadings in areas thousands of miles away, since iron and phosphorus from Saharan dust storms provide much of these critical nutrients for the North Atlantic and Amazon (5). Likewise, if the atmospheric loading of certain windblown dust that reflects sunlight is reduced, this will tend to offset the effect due to increased surface albedo.
(7) Since albedo enhancement is not covered by the present Kyoto treaty, a conversion from tons of carbon removed to Wm-2reduced must be developed and the treaty modified to allow credits for albedo enhancement.
(8) The maximum potential coverage area that can be projected for this use can offset GHG forcings and warming from either the periods 1750-2010 or 2010-2070, but not both. Albedo enhancement is not a substitute for significant action on reducing emissions, rather, it is a delaying tactic to allow technological innovations for achieving emission reductions to become cost effective and widely used.
(9) Companies and governments involved in this work will require an international Price-Anderson type act indemnifying them from lawsuits resulting from this work. Based on previous attempts to modify weather, e.g., Project Storm Fury in the 1960’s and 1970’s (6-8), it can be expected that every farmer whose cow drops dead will be encouraged by enterprising attorneys to blame the GAEP and sue the organizations involved.
