---

Global net primary productivity in terms of energy units

Value	0.21 W/m^2
Organism	Biosphere
Reference	Jorg Overmann and Ferran Garcia-Pichel, The Phototrophic Way of Life, Prokaryotes (2006) 2:32–85 chapter 1.3, edited by Stanley Falkow, Eugene Rosenberg, Karl-Heinz Schleifer, Erko Stackebrandt DOI: 10.1007/0-387-30742-7_3 p.32 left column 2nd paragraph
Comments	P.32 left column 2nd paragraph: "At present the flux of electromagnetic energy supports a total primary production of 172.5×10^9 tons dry weight/year (168 g C/m^2/year, Whittaker and Likens, 1975 BNID 100602). If this global primary production is converted to energy units (39.9 kJ/gC, assuming that all photosynthetic products are carbohydrate), 0.21 W/m^2 and thus 0.13% of the available solar energy flux [given 160 W/m^2 of solar radiation reaching the earth from the sun on the average] are converted into chemical energy. Even at this low efficiency, the chemical energy stored in organic carbon still exceeds geothermal energy by at least one order of magnitude."
Entered by	Ron Milo - Admin
ID	100605