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An assessment of net energy and supply potentials was performed to evaluate cassava utilization for fuel ethanol in Thailand. Just recently, the Thai government approved the construction of 12 cassava ethanol plants with the total output of 3.4 million liters per day by the next 2 years (2007 and 2008). The cassava fuel ethanol (CFE) system involves three main segments: cassava cultivation including processing, ethanol conversion, and transportation. All materials, fuels, and human labor inputs to each segment were traced back to the primary energy expense level. Positive Net Energy Value and Net Renewable Energy Value, 8.80 MJ/L and 9.15 MJ/L, respectively, found for the CFE system in Thailand proved that it is energy efficient. Without coproduct energy credits, CFE in Thailand is even more efficient than CFE in China and corn ethanol in the United States. Regarding supply potentials, about 35% of the national cassava production would be used to feed approved CFE factories. A shift of cassava to ethanol fuel rather than its current use for chip/pellet products could be a probable solution.

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Past studies suggest that forest fires contribute significantly to the formation of ozone in the troposphere. However, the emissions of ozone precursors from wildfires, and the mechanisms involved in ozone production from boreal fires, are very complicated. Moreover, an evaluation of the role of forest fires is prevented by the lack of direct observations of the ozone precursor, nitrogen oxides (NOx), and large uncertainties exist in the emissions inventories currently used for modelling. A comprehensive understanding of the important processes and factors involving wildfires has thus been unobtainable. We made 16 year consistent analyses of NOx emissions from boreal wildfires by using satellite observations of tropospheric nitrogen dioxides (NO 2 ) from 1996 to 2011. We report substantial interannual variability of tropospheric NO 2 originating from large boreal fires 2009. Monthly comparisons of NO 2 enhancements with fire radiative power (FRP) show reasonably strong correlation, suggesting that FRP is a better proxy than burned area for boreal fire NOx emissions. We provide space-based constraints on NOx emission factors (EFs) for Siberian and Alaskan fires. Although the associated uncertainty is relatively large, the derived EFs fall into a in reasonably agreeable range with those previously determined by in situ ground-based and airborne observations over these regions.

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