http://notes.helsinki.fi/halvi/tiedotus/pressrelease.nsf/e1e392ad852e72f5c225680000404fa8/78a4c6ca61b92751c225762e002fcf6f?OpenDocument Author: Kirsikka.Mattila 11.09.2009 11:42
University of Helsinki
Communications / Viikki Science Campus
11 September 2009
The change in Arctic nature foreshadows the global environment of the future
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.
…http://www.iab.uaf.edu/news/index.php?newsrel=77 IAB News Releases
UA scientists seek new emphases in Arctic climate change research
FOR IMMEDIATE RELEASE
10 September 2009
FAIRBANKS, Alaska -- Much of circumpolar Arctic research focuses on the physical, direct changes resulting from climate warming such as sea ice retreat and temperature increases. “What’s understudied is the living component of the Arctic and that includes humans,” said Syndonia “Donie” Bret-Harte, associate professor of biology at the University of Alaska Fairbanks and co-author of a paper to be published September 11, 2009 in the journal Science.
The paper reviews current knowledge on the ecological consequences of climate change on the circumpolar Arctic and issues a call for action in several areas of global climate change research.
“Humans live in the Arctic with plants and animals and we care about the ecosystem services such as filtering water, fiber and food production and cultural values that the Arctic provides” said Bret-Harte, who specializes in Arctic plant ecology in Alaska.
The global average surface temperature has increased by 0.72 F (0.4 C) over the past 150 years and the average Arctic temperature is expected to increase by 6 C. “That’s a mind bogglingly large change to contemplate and keep in mind that no one lives at the average temperature,” Bret-Harte said.
The international team of scientists who collaborated on this paper reviewed dozens of research documents on the effects of circumpolar Arctic warming. They note that numerous direct effects including lengthening of growing season following a rapid spring melt, earlier plant flowering and appearance of insects following a warmer spring, deaths of newborn seal pups following melting of their under-snow birthing chambers have other, often more subtle, indirect effects on plants, animals and humans that warrants increased attention.
Understanding how changes in plant and animal populations affect each other and how they affect the physical or nonliving components of the Arctic is critical to understanding how climate warming will change the Arctic.
One effect studied intensively at the UAF Institute of Arctic Biology Toolik Field Station on Alaska’s North Slope is shrub expansion on the tundra.
“Shrubs are increasing on the tundra as the climate warms and more shrubs will lead to more warming in the spring,” said Bret-Harte. Snow reflects most incoming radiation, which is simply light that can transfer heat. Shrubs that stick out of the snow in spring absorb radiation and give off heat. In this positive feedback cycle, the heating of the air immediately above the snow warms the snow, causing it to melt sooner. Warmer soils lead to increased nutrient availability, which contributes to greater shrub growth, which then contributes to still more warming.
Another effect studied intensively in Alaska occurs under the snow.
“We need to better understand how winter comes and goes and how that drives shifts in plant-animal interactions,” said Jeff Welker, professor of biology at the University of Alaska Anchorage. When it didn’t snow at Toolik Field Station until Thanksgiving a few years ago the soil got cold and stayed cold. So cold that microbes in the soil were barely active. The spring green-up was slow in coming and likely affected caribou forage, says Welker.
In 2008, the snow started falling in September and never quit. The warmer winter soils with their active microbes were insulated from the cold and were able to provide nutrients to plants that stimulated growth.
The authors call for immediate attention to the conservation of Arctic ecosystems; understanding the ecology of Arctic winters; understanding extreme events such as wildfires and extended droughts; and the need for more baseline studies to improve predictions.
“This paper identifies gaps in our knowledge, what we need to be doing and where the public needs to spend its money,” said Welker.
The research team was led by Eric Post, Penn State University, and included biologists, ecologists, geographers, botanists, anthropologists, and fish and wildlife experts from the University of Alberta and the Canadian Wildlife Service in Canada; Aarhus University and the University of Copenhagen in Denmark; the University of Helsinki in Finland; the Arctic Ecology Research Group in France; the Greenland Institute of Natural Resources in Greenland; the University Centre on Svalbard, the University of Tromsø, and the Centre for Saami Studies in Norway; the University of Aberdeen and the University of Stirling in Scotland; Lund University and the Abisko Scientific Research Station in Sweden; the University of Sheffield in the UK; and the Institute of Arctic Biology and the U.S. Geological Survey at the University of Alaska Fairbanks, the Environment and Natural Resources Institute of the University of Alaska Anchorage, and the University of Washington in the United States.
Support was provided by Aarhus University, The Danish Polar Center, and the U.S. National Science Foundation.
CONTACT: Syndonia “Donie” Bret-Harte, associate professor of biology, Institute of Arctic Biology University of Alaska Fairbanks. 907-474-5434, ffmsb@uaf.edu.
Jeffrey Welker, professor of biology, director, Environment and Natural Resources Institute University of Alaska Anchorage. afjmw1@uaa.alaska.edu, 907-257-2701
Marie Gilbert, information officer, Institute of Arctic Biology, University of Alaska Fairbanks. 907-474-7412, megilbert@alaska.edu
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