19 Mar 2014:
CO2 Levels Have Crossed
400 ppm Threshold Far Earlier This Year
Concentrations of carbon dioxide in the atmosphere have reached the 400 parts per million threshold two months earlier this year than last, an indication that the planet will soon experience the 400 ppm level year-round, according to
scientists from the Scripps Institute of Oceanography. Last year was the first time in hundreds of thousands of years that the 400 ppm threshold was crossed. Scripps scientists expect
CO2 levels to hover around 400 ppm for the next two months, when the Northern Hemisphere spring will go into full bloom and plants will suck CO2 from the atmosphere until going dormant in the fall. "It’s just a matter of time before it stays over 400 forever," said Ralph Keeling, who took over the CO2 monitoring program from his father, Charles David Keeling, who started it in 1958. Since then, atmospheric CO2 levels have risen steadily from 313 ppm as the world continues to burn fossil fuels. Scientists estimate it's been 800,000 to 15 million years since the planet has seen concentrations this high.
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A look at how acidifying oceans could threaten the Dungeness crab, one of the most valuable fisheries on the U.S. West Coast. Watch the video.
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An aerial view of why Europe’s per capita carbon emissions are less than 50 percent of those in the U.S. View the photos.
An indigenous tribe’s deadly fight to save its ancestral land in the Amazon rainforest from logging. Learn more.
video series looks at the staggering amount of food wasted in the U.S. – a problem with major human and environmental costs. Watch the video.
Residents of the Chocó Rainforest in Ecuador are choosing to plant cacao over logging in an effort to slow deforestation.
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Tribal people and ranchers join together to stop a project that would haul coal across their Montana land. Watch the video.