4.4 Implementation Approach
4.4.1 Overview
The approach to implementation of the surface coverage will involve several distinct efforts. Computer modeling will be performed to predict possible outcomes. The selection of the plastic film will require laboratory development studies. Once the film has been selected and developed, field studies will be carried out that will ultimately lead to large-scale installation of the cover that will require monitoring and maintenance. Each of these activities is described in this section.
4.4.2 Modeling
Before any field tests or certainly any full-scale land coverage are attempted, computer simulations of the proposed change in surface albedo on climate must be performed. Unfortunately, models available today require a resolution of almost 250 Km x 250 Km (24,000 square miles) in the horizontal direction (9, 17). This limits them mostly to simulations of global climate change.
Some models are capable of resolving changes on a regional, i.e., hemispheric scale, but nothing is available that can, e.g., predict future climate based on coverage of 1 square mile or even 100 square miles of albedo enhanced surface. These areas are simply too small to be resolved. Since areas on this scale would have to be investigated by actual coverage before full-scale coverage could be attempted, we will not have access to modeling data for comparison for these smaller coverage areas. Work is ongoing to reduce the size of the grid required, but improvements are largely a function of increases in computing power that mean we will have to wait for future generations of computers to be developed before grid sizes can be reduced significantly (121).
The modeling that can be performed is global climate modeling. This will predict what effects various full-scale treatments will have on future climate. For example, if the albedo of 50,000 square miles of the Sahara is increased from 0.36 to 0.8, the existing models will be able to generate future climate conditions for the entire planet based on this increase in albedo.
Adverse future climate changes such as extreme temperature drops within and outside the region of coverage may preclude the use of the coverage altogether. One would expect, e.g., that changing the surface albedo this much would result in much lower daytime and nighttime temperatures in the 50,000 miles covered as well as somewhat lower temperatures in the surrounding areas. The greater the amount of land covered, the more far reaching the impact will be on temperatures, wind flow patterns, humidity, rainfall and other climate variables. Ideally, the coverage would be spaced both in time and location so that dramatic changes to climate would not occur, while at the same time those changes expected due to global warming would be mitigated.
