Fighting Global Warming: Artificial Trees and Slime-Covered Buildings

The most practical and immediate steps we can take to slow global warming may be lining roadways with towering "artificial trees" and covering buildings with algae bioreactors, argues a new report from Britain's Institution of Mechanical Engineers. The group believes that geoengineering (a broad term for climate-altering technologies) may be necessary to reduce carbon dioxide levels immediately, while governments continue to bicker about how to transition to a low-carbon future.