Year: 2014

Chicken Little was wrong! A new study confirms that increased atmospheric carbon dioxide lengthens the plant growing season.

Previous studies have documented a lengthening of the growing season in many parts of the world. In the United States, the time between the last spring frost and the first autumn freeze has gone up by nearly two weeks since 19002; in Europe, a study of more than 540 plant species found that, on average, spring events such as flowering had shifted about a week earlier from 1971 to 2000, and the onset of autumn had been pushed back by about four days3.

Such shifts have long been attributed to warming temperatures. But CO2 also plays a part, says study co-author Heidi Steltzer, an ecosystem ecologist at Fort Lewis College in Durango, Colorado.

Putting aside the uncertainty about whether carbon dioxide can even cause global warming, the assumption that global warming itself will be a bad thing has never been demonstrated clearly, while there is evidence that it might actually be beneficial.