Tall grasses in the San Joaquin valley in California suck carbon dioxide out of the air and store it in the soil. It's one option that environmentalists are pursuing for greenhouse gas "offsets" that can be bought and sold in the state.
Can 'Carbon Ranching' Offset Emissions In Calif.?
()Climate experts are thinking about growing dense fields of weeds to help soak up carbon dioxide from the atmosphere. This would require flooding dense, carbon-rich wetland soils of the San Joaquin Valley, and farmers hope money they make from capturing greenhouse gases would make up for the lost acreage.
Politics
How Payroll Tax Cut Affects Social Security's Future()
President Obama says that unless a temporary payroll tax cut is extended this month, 160 million Americans would see their taxes increase. But there's concern on both sides of the political aisle that the payroll tax holiday might be undermining the solvency of Social Security.
Technology
How Twitter's Trending Algorithm Picks Its Topics()
Sometimes a topic that seems hot, like Occupy Wall Street, doesn't appear on trending lists, leading some activists to accuse Twitter of censorship. But the secret algorithmic formula prefers stories of the moment to enduring hashtags, so it ignores topics that are popular over a long period of time.
Asia
Clean Air A 'Luxury' In Beijing's Pollution Zone()
For more than half of the past 60 days, the air pollution in the Chinese capital has hit levels hazardous to human health. Experts estimate long-term exposure to such pollution could reduce life expectancy by as much as five years. NPR's Louisa Lim describes what it's like living in the city.