In Arctic areas, climate change is progressing faster than in any other location on Earth. Researchers at the University of Helsinki have participated in two new studies indicating that the changes are astonishingly fast. Many original species of Arctic areas are in jeopardy, as global warming causes species from southern areas to migrate north, where they occupy the living space of the original species.
The renowned Science magazine will publish a joint article by 25 researchers specialising in Arctic ecology. Olivier Gilg, researcher at the Faculty of Biosciences at the University of Helsinki, is one of the article's contributing authors. The article was written under the supervision of Eric Post, professor at Penn State University.
The study results presented in the article indicate that the Arctic eco-system has experienced immense changes in the last twenty years. At many levels, the changes impact the eco-system services that the environment provides for people: the effects extend to the adequacy of natural resources, food production, climate temperature, and result in changes to the landscape. The changes in the northern nature can be interpreted as an advance warning of what is to be expected on all latitudes.
Arctic foxes and northern birch areas are in trouble
The results show that spring begins considerably sooner than before. The blossoming and pollination period of plants starts as much as twenty days sooner in comparison to the situation ten years ago. Predators are in dire straits because nutrition is now available too soon in relation to the otherwise favourable nesting period. The distribution of many insects has moved even more north. European winter moths, for example, have destroyed extensive birch areas in Lapland after moving north. Species invading new areas might supersede the original species in the area this is already happening to Arctic foxes, which are currently being overrun by red foxes.
Ivory gulls, ringed seals, polar bears and narwhals are examples of species with a small distribution and specialised habitats, and such species will be the first ones to suffer from the changes. They need the ice in seas to procreate and to find shelter from predators.
A publication concerning the indirect impact of climate change
Climate change also has indirect effects that appear in the interaction between different species. Olivier Gilg and academy professor Ilkka Hanski from the University of Helsinki have teamed up with Benot Sittler, a researcher from the University of Freiburg, and studied the waning of the previously cyclical population dynamics of the collared lemming in Greenland. The results will be published in the journal Global Change Biology at the end of the year.
With mathematical models, the researchers showed that the drastic change in the population dynamics of collared lemmings is explained by the fact that snow melts sooner than before: the lemmings do not procreate as long as before below the snow, and are also easier for predators to hunt. In addition, frost-melt events in winter form ice layers in the snow layer or at the tundra's surface, which is why the lemmings are unable to find food like they used to.
|Contact: Ilkka Hanski|
University of Helsinki