Word: air
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Dates: during 2000-2009
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Some of the best evidence linking rising carbon dioxide levels to a warmer world comes from the coldest places on earth. Samples of ancient air extracted from deep inside the Antarctic and Greenland ice caps make it clear that CO2 is scarce in the atmosphere during ice ages and relatively abundant during warmer interglacial periods - like...
...relationship between CO2 and climate is clear going back about 800,000 years. Before that, however, it gets murkier. That's largely because ice and air that old haven't yet been found. So scientists rely instead on indirect measurements - and these have led to a climate mystery: some episodes of past warming, including a planetary heat wave about 15 million years ago and another about 3.5 million years ago, seem to have happened without a rise in CO2. No one quite understands why. Maybe other greenhouse gases were the cause - methane, for example. Or maybe...
...fossils are abundant in ancient ocean sediments, so they're a particularly good tracer of the past. But they used a new technique to measure CO2: looking at how much of the element boron was present in the foraminifera's shells. When there's lots of CO2 in the air, there's also more in the top layers of seawater, where the relevant species of foraminifera live. That makes the water more acidic, which in turn makes the tiny animals incorporate less boron into their shells as they grow...
Every year, recipients of the Prizes shower Miss Sweetie Poo with gifts in attempt to get more air-time. This year’s included milk, a stuffed cow, a sombrero and a bottle of tequila. "It was bad milk," Isabel observed. "I liked the sombrero, but they wouldn’t let me keep it. I don’t know what they did with the wine. They wouldn’t let me take it home for Mommy and Daddy to drink...
After 30 years in the military, Roosevelt Dickerson wasn't looking for a new career challenge. A retired Air Force chief master sergeant, he took some small-time jobs here and there for a few years - nothing too strenuous, nothing too taxing. Then he got a call from his old boss, the Defense Department, asking if he would be interested in trying one of the most strenuous, taxing jobs around: teaching. They wanted to know if he would consider joining the Troops to Teachers (TTT) program, which helps place former military personnel in U.S. classrooms. As Dickerson, 57, recalls...