Not only the CO2 is responsible for global warming, as there is not only one source of pollution affecting our planet. By studying the impact of a global scale biofuel program, a report led by Jerry Melillo from the Marine Biological Laboratory (MBL) predicts that the carbon loss resulting from the displacement of food crops and pastures for biofuel crops may be twice the CO2 the lands dedicated to biofuels would emit.
Melillo and his colleagues studied the effects of direct an indirect land use on greenhouse gas emissions (not only CO2), correlated with the increase of biofuel production over this century. Direct land-use emissions are produced from a land dedicated entirely to biofuel production, while indirect land-use emissions refer to the situation when the biofuel production is in the detriment of agricultural croplands, moving them to another location, causing additional land-use changes and an increase in CO2 emission.
Currently, no major states include CO2 emissions from biofuel-related land-use changes in their carbon loss accounting and there is concern about the practicality of including such losses in a system designed to reduce fossil-fuel emissions.
“Our analysis, which we think is the most comprehensive to date, shows that direct and indirect land-use changes associated with an aggressive global biofuels program have the potential to release large quantities of greenhouse gases to the atmosphere,” says Melillo.
Melillo simulated two global land-use scenarios in the study:
In Case 1, the natural areas are converted to produce biofuel crops
In Case 2, the land was not converted, existing managed land was used to grow the biofuel crops.
Both cases are keeping into account the 550ppm CO2 concentration threshold, a target often talked about in climate policy discussions. Under such a climate policy, fossil fuel use would become more expensive and the introduction of biofuels would accelerate, ultimately increasing the size of the biofuels industry and causing additional effects on land use, land prices, and food and forestry production and prices.
The problem is biofuels need fertilizers to grow properly, as demanded by the fuels market, and Melillo’s simulations revealed that over the century, N2O emissions from those fertilizers will surpass CO2 in terms of warming potential. They say that by 2100 biofuel production will be responsible for more than half of the total N2O emissions from fertilizers.
So, one way or the other, my opinion is that if we’ll continue to harvest crops for our cars and industries, we’ll get to the same point – harmful gases will anyway be released into the atmosphere, worsening the global warming. The only viable, long-term solution is to find any other source of energy than burning things or starving other people because we want to fill our tanks. We might even end up cutting forests to use the land for producing biofuel.