The geobiosphere emergy baseline: A synthesis

The concept of emergy defined as the available energy (or exergy) of one form used up directly and indirectly to produce an item or action (Odum, Environmental Accounting Emergy and Environmental Decision Making, John Wiley & Sons, Inc., 1996) requires the specification of a uniform solar equivalent exergy reference, or geobiosphere emergy baseline (GEB). Three primary exergy sources of different origins interact to drive processes within the geobiosphere. Each of these sources are expressed in solar equivalent exergy from which, all other forms of energy can be computed, so that they may be expressed as emergy in units of solar emjoules. If emergy practitioners reference their work to a single agreed-upon baseline, then all research products resulting from the application of the emergy approach will be inherently consistent and valid comparisons can then be made easily. In this paper, we synthesize information from three new calculation procedures of the emergy baseline for the geobiosphere and propose a unified solution.