Thawing permafrost could release large amounts of greenhouse gases to the atmosphere causing even more global warming !

This initiative was launched because there is considerable concern and increased awareness both within the international scientific community and the general public about the effects that global warming could have on frozen grounds in Arctic regions (Main Photo). A significant proportion of this permafrost would start to thaw out over the coming decades, with a potential release of large amounts of greenhouse gases (both carbon dioxide and the much more potent methane) to the atmosphere from previously frozen soil organic matter that will start to decompose. This is a so-called positive feedback within the Earth System, as climate warming results in permafrost thawing that causes a further increase of greenhouse gases in the Earth's atmosphere resulting in even more warming. We are not dealing only with a gradual process related to progressive thawing of the ground with depth over time. Also more dramatic events like ground subsidence due to melting of buried ice bodies (Photo 2) and lateral erosion along the edges of thaw lakes (Photo 3) would accelerate the release of greenhouse gases.

Climate warming is resulting from disruption of the global carbon (C) cycle. The Arctic is already warming significantly and the region governs some critical feedbacks in global change, including release of huge C stores from high-latitude soils, shift in albedo due to changes in vegetation and snow cover, and potential effects on the thermohaline circulation as a result of alterations in river discharge to the Arctic Ocean. However, the links between climate, the C cycle, energy balance, and hydrology are complex and our understanding of them – and their impact on Arctic ecosystems – is poor. ABACUS aims to provide answers to these critical questions.

The polar environments are rapidly changing and leaving a lasting impact on the freshwater and terrestrial ecosystems within them. However the region is so vast and diverse that the knowledge of what drives these changes is limited. This project will assess how terrestrial and freshwater ecosystems and environments have changed in the past and record their current status and biodiversity. IPY provides a timely opportunity for passing on knowledge to new generations of researchers and forming a new and authoritative baseline of environmental characteristics with which to examine future changes. Among the sites to be studied are some first examined during the ICSU-sponsored International Biological Programme, which will allow some assessment of changes over recent decades.

There is increasing recognition that multiple environmental changes are occurring in the northern regions of Europe. Some of these environmental changes, for example climate warming, levels of UV-B radiation, and habitat fragmentation, are projected to continue leading to impacts on the lands of the Nordic countries unprecedented since deglaciation some 10,000 year ago. Three ENVISNAR projects studying these processes are profiled below:

The proposed activity aims at establishing a bipolar network to obtain data needed to quantify properties of aerosols at high latitudes, including seasonal background concentrations by measurements of aerosol optical depth (AOD), spectral characterizations, and the evolutionary patterns of the natural and anthropogenic processes that perturb the aerosol cycles. An effort to quantify direct and indirect climate forcing by polar aerosols will be made through a set of closure experiments using observations in conjunction with model calculation and satellite data.

Our IPY activities are designed to further an interdisciplinary and cross-institutional discussion about climate change, Arctic peoples, and international policy through: a series of lectures and workshops; a museum exhibition and related publications; and, the organization of the 2007 Arctic Science Summit Week (ASSW).