Some of the findings of the report:

• Activities in the Iraq war have released at least 141 million metric tons of carbon since March 2003, equal to putting 25 million more cars on the road in the U.S. 
• Projected U.S. spending on the Iraq war would be enough for all of the GLOBAL investments required in renewable energy generation between 2008 and 2030 to stop current global warming trends.
• The $600 billion allocated by Congress for Iraq military operations could have built 9000 wind farms, enough to meet a quarter of U.S. present electricity needs.
• In 2006, The U.S. spent more on the Iraq War than the entire world spent on renewable energy investment.
• U.S. presidential candidate Barack Obama has pledged to spend “$150 billion over 10 years to advance the next generation of green energy technology and infrastructure.” The U.S. spends nearly $150 billion on the Iraq War in just 10 months.

 Where do these Iraq War emissions come from?

Fuel used in combat, oil well fires and increased gas flaring, the increase in cement consumption due to reconstruction efforts and security needs, and explosives and chemicals that contribute to global warming.

The report authors note that these emissions estimates are very conservative

Source: A Climate of War: The War in Iraq and Global Warming By Nikki Reisch and Steve Kretzmann, March 2008