Apollo 17 Astronaut Harrison "Jack" Schmitt addresses a plenary session at ICCC4 in Chicago in 2010.
The Heartland Institute's Fourth International Conference on Climate Change (ICCC-4) took place in May 2010 in Chicago, Illinois, addressing the theme “Reconsidering the Science and Economics.”

The speakers and audience considered how new scientific discoveries have cast doubt on how much of the warming of the twentieth century was natural and how much was man-made, and governments around the world are beginning to confront the astronomical cost of reducing emissions.

Geologist, astronaut, and former U.S. Senator Harrison Schmitt kicked off the event with an opening keynote presentation on constitutional law as it relates to climate change issues. Climate Audit author Steve McIntrye followed with a chronology of "hide the decline" and other Climategate-related issues.

Economists, meanwhile, spoke about the cost of slowing or stopping global warming exceeds the social benefits.

Download the program here.