Assessing the global environmental sources driving the geobiosphere: A revised emergy baseline

The empower that is derived from solar radiation, tidal momentum and geothermal sources drives the productive processes of the geobiosphere and is responsible for developing gradients of potential energy transformed into secondary energy and tertiary sources. In this paper we establish the geobiosphere emergy baseline (GEB) based on earlier methods proposed by Odum (2000) and refinements by Brown and Ulgiati (2010). After revising the solar exergy input and our previous interpretation of the sources and magnitudes of geothermal exergy, we compute a revised solar equivalent exergy and solar equivalence ratios (SERs) of geothermal and tidal inputs to the geobiosphere dynamic. A Monte Carlo simulation that includes the revised solar exergy flow of geothermal inputs and uncertainty in the flows yields SERs of 26,300 seJ J−1 and 5500 seJ J−1 for tidal and geothermal sources respectively. The solar exergy remains 3.6 E+24 sej y−1, while the solar equivalent exergy of tidal and geothermal sources were 3.1 E+24 seJ y−1, and 5.4 E+24 seJ y−1 respectively, resulting in a GEB of 12.1 E+24 seJ y−1.