Spring in the Arctic has been registered weeks earlier than a decade ago and is likely linked to climate warming, a team of researchers said.
"Despite uncertainties in the magnitude of expected global warming over the next century, one consistent feature of extant and projected changes is that Arctic environments are and will be exposed to the greatest warming," said Toke T. Hoye of the National Environmental Research Institute, University of Aarhus, Denmark in the June 19 issue of the journal Current Biology.
"Our study confirms what many people already think, that the seasons are changing and it is not just one or two warm years but a strong trend seen over a decade," Hoye added.
The researchers from Denmark and the US used phenology, "the study of the timing of familiar signs of spring seen in plants, butterflies, birds, and other species" to track warming.
At a site monitored in northern Greenland, researchers noted that flowering, emergence dates of several species and egg-laying had advanced on average by 14.5 days.
In some species the early advancement was 30 days.
In parts of Europe the early advancement during the same period was 2.5 days per decade and 5.1 days globally.
"We were particularly surprised to see that the trends were so strong when considering that the entire summer is very short in the High Arctic with just three to four months from snow melt to freeze up at our Zackenberg study site in northeast Greenland," Hoye said.
Hoye's team said that the varied response by species "could lead to particular problems by disrupting the complex web of species interactions."