Obama's Climate Change Last Resort

Can the United States engineer its way out of global warming? According to President Obama's top science adviser, John Holdren, if the globe reaches certain "tipping points," such as the loss of Artic sea ice in the summer, or global temperatures rising by more than 3.6 degrees, scientists are considering "geoengineering" as a solution. This new, popular concept in the scientific community involves such measures as launching sulfur particles into the sky (much like a volcano) that would block out harmful sunlight, and creating giant, man-made trees that would vacuum carbon dioxide out of the air. Of course, scientists are uneasy about tampering in God's domain to such a degree, and caution that geoengineering should only be a weapon of last resort.