Since the 1930s, Louisiana has lost roughly as much land as makes up the state of Delaware.
"If you put the state of Delaware between New Orleans and the ocean, we wouldn't need any levees at all," says John Barry, vice president of the Southeast Louisiana Flood Protection Authority-East. "There is this large buffer of land that has disappeared, and that buffer makes New Orleans much more vulnerable to hurricanes."
The continental U.S. experiences small earthquakes every day. But over the past few years, their numbers have been increasing. Geoscientists say the new epidemic of quakes is related to industrial wastewater being pumped into underground storage wells.
Now there's new research that reveals two trigger mechanisms that may be setting off these wastewater quakes — other, larger earthquakes (some as far away as Indonesia), and the activity at geothermal power plants.
America's hugely productive food system is one of its success stories. The nation will export a projected $139.5 billion in agricultural products this fiscal year alone. It's an industry that supports "more than 1 million jobs," according to Agriculture Secretary Tom Vilsack.
But all that productivity has taken a toll on the environment, especially rivers and lakes: Agriculture is the nation's leading cause of impaired water quality, according to the U.S. Environmental Protection Agency.
Populations of frogs, salamanders and other amphibians are declining at an average rate of 3.7 percent each year, according to a U.S. Geological Survey study released this week. Researchers say the study is the first to calculate how quickly amphibians are disappearing in the United States.
"If the rate observed is representative and remains unchanged, these species would disappear from half of the habitats they currently occupy in about 20 years," according to the USGS.