An article from the journal, Science, points out that when making carbon balances for biofuel production, one must account not only the carbon that is sequestered from the growth of the biofuel crop, but also other factors that result in carbon emissions. These factors include those resulting from the conversion of food lands to biofuel crop plantations. Using a “worldwide agricultural model”, researchers assessed that U.S. corn ethanol actually increases carbon emissions. Estimates show the carbon emissions would double in 30 years and the increase would continue for about 167 years. Their study raises second thoughts about large scale land conversions for biofuels. Details of their research can be obtained from the Science journal website (URL above)..