Changing seasons |
The timing of spring in the Arctic has become more and more erratic in the past 25 years, leading to growing discrepancies between the behaviour of animals and plants and the conditions they depend on. Since 1996, Niels Schmidt at Aarhus University in Denmark and his colleagues have been monitoring the ecosystem at Zackenberg, a mountain in north-east Greenland. When they analysed the first 10 years of data, they found that spring was arriving around two weeks earlier in 2005 compared with 1996. But now that trend has been replaced by extreme variability from year to year, with animals and flowers emerging at different times. |