A truck drives on top of a levee that protects a soybean field in New Madrid County, Mo., when the Mississippi River floods. Kristofor Husted/KBIA hide caption

itoggle caption Kristofor Husted/KBIA

Quinault Indian Nation President Fawn Sharp stands on the docks as tribal crabbers unload their catch. The tribe has vowed to fight the oil train-to-ship terminals proposed for Grays Harbor. Ashley Ahearn/KUOW hide caption

itoggle caption Ashley Ahearn/KUOW

Crew members pull an oyster dredge in Tangier Sound of the Chesapeake Bay near Deal Island, Md., in 2013. A study found that the Chesapeake Bay shellfishery is a "hot zone" for ocean acidification. Patrick Semansky/AP hide caption

itoggle caption Patrick Semansky/AP

Freight Farms are shipping containers modified to grow stacks of hydroponic plants and vegetables — anywhere, 365 days a year. Courtesy of Freight Farms hide caption

itoggle caption Courtesy of Freight Farms

"Understanding consciousness is a real key, I think, both to understanding the universe and to understanding ourselves." - David Chalmers James Duncan Davidson/TED hide caption

itoggle caption James Duncan Davidson/TED

Robert Davies (standing) and the quartet during a performance of "The Crossroads Project." Musicians include (left to right) Robert Waters, Rebecca McFaul, Anne Francis Bayless and Bradley Ottesen. Andrew McCallister /Courtesy of The Crossroads Project hide caption

itoggle caption Andrew McCallister /Courtesy of The Crossroads Project

To put their probes into the Arctic Ice, researchers hitched a ride on a South Korean icebreaker. Courtesy of Craig M. Lee/University of Washington hide caption

itoggle caption Courtesy of Craig M. Lee/University of Washington

A fisherman collects water on a beach littered with trash at an ecological reserve south of Manila in 2013. Francis R. Malasig/EPA/Landov hide caption

itoggle caption Francis R. Malasig/EPA/Landov

The eruption of Mount Pinatubo in the Philippines in 1991 spewed almost 20 million tons of sulfur dioxide into the atmosphere, causing worldwide temperatures to drop half a degree on average. Arlan Naeg/AFP/Getty Images hide caption

itoggle caption Arlan Naeg/AFP/Getty Images

In a project called "Natural Frequencies," the bells in the Campanile on the University of California, Berkeley campus were recently programmed to play a score composed in real time by the seismic shifts taking place along the Hayward fault. Eric Risberg/AP hide caption

itoggle caption Eric Risberg/AP

A Falcon 9 SpaceX rocket stands ready for a sunset launch from complex 40 at the Cape Canaveral Air Force Station in Cape Canaveral, Fla., on Sunday. It will be carrying aloft the DSCOVR satellite. John Raoux/AP hide caption

itoggle caption John Raoux/AP