Kill King Corn

Nature, Editorial page.  Mentions Earth Track's estimates of subsidies per mt CO2-equivalent, calculated for the IISD:

...The common complaints about biofuels — and they seem to become more common by the day — are that they are expensive and ineffective at reducing fossil-fuel consumption, that they intensify farming needlessly, that they dress up discredited farm subsidies in new green clothes, and that they push up the price of food. All these things are true to some extent of corn-based ethanol, America's biofuel of choice, and many are also true of Europe's favoured biodiesel plans.

As far as the greenhouse goes, figures from the International Institute for Sustainable Development's Global Subsidies Initiative put the cost of averting carbon dioxide emissions by using corn-based ethanol at more than $500 a tonne of carbon dioxide. [fn]See this report, specifically Table 4.5 on page 35.[/fn] What's more, the heavy use of nitrogen fertilizer in growing corn leads to significant emissions of nitrous oxide, an even more potent greenhouse gas...