Cornfields in Malawi, like this one, can be used to grow legumes such as pigeon peas, which replenish the soil and are more nutritious than corn. Michelly Rall/Getty Images hide caption

itoggle caption Michelly Rall/Getty Images

Mexico's President Felipe Calderon (left) starts a wind turbine that will help power the United Nations Climate Change Conference in Cancun. Officials will spend the next two weeks debating how to mobilize money to cope with climate change as temperatures climb, ice melts and seas rise. Israel Leal/AP hide caption

itoggle caption Israel Leal/AP

The deep-water-research submarine Alvin is launched from Atlantis. Scientists are studying how ecosystems in the Gulf of Mexico may have been affected by the Deepwater Horizon oil spill. Richard Harris/NPR hide caption

itoggle caption Richard Harris/NPR

A hybrid solarized gas turbine power station owned by AORA Solar, a new Israeli company pushing solar hybrid technology, sits in the southern Israeli kibbutz of Samar. David Buimovitch/AFP/Getty Images hide caption

itoggle caption David Buimovitch/AFP/Getty Images

Shopper Andrea Harrison says despite reports about lead in reusable bags, she'll keep using them as her way of keeping plastic out of waterways. Elizabeth Shogren/NPR hide caption

itoggle caption Elizabeth Shogren/NPR