The activities of the Finnish permafrost community are going on both in Eurasia and Greenland. The investigations are based on large empirical field studies, long-term monitoring of permafrost and on spatial modelling. Permafrost studies in Finland are covering a wide range of different activities: e.g. bedrock borehole investigations, spatial modelling of vegetation-frost dynamics, climate change impact assessments based permafrost modelling and greenhouse gas emissions from high-latitude wetlands.
Permafrost modelling network at the Finnish Environment Institute (S. Fronzek and T. R. Carter) and Department of Geosciences and Geography at the University of Helsinki (M. Luoto) have continued to estimate future changes in the distribution of palsa (permanently frozen peat hummocks) mires in Fennoscandia, and the implications of these changes for greenhouse gas budgets and nature conservation. Recent developments in climate modelling have made it possible to express projections of regional climate change for Europe probabilistically quantifying various aspects of climate modelling uncertainty. These typically involve large ensembles of climate model simulations combined with some statistical analysis. Probability distributions are fitted for projected changes in key climate variables. Fronzek and co-authors present an analysis of different sources of impact model uncertainty and combine this with probabilistic projections of climate change. Climatic envelope models describing the spatial distribution of palsa mires in northern Fennoscandia were calibrated for three baseline periods, multiple modelling techniques and 25 versions sampling the parameter uncertainty of each technique – a total of 600 models. The sensitivity of these models to changes in temperature and precipitation was analysed to construct impact response surfaces. Based on the most robust models, it was estimated as very likely (>90% probability) that the area suitable for palsas is reduced to less than half the baseline area by the period 2030–2049 and as likely (>66% probability) that the entire area becomes unsuitable by 2080–2099 (A1B emission scenario).
The Top-level Research Initiative (TRI) is the largest joint Nordic research and innovation initiative to date. The initiative aims to involve the very best agencies and institutions in the Nordic region, and promote research and innovation of the highest level, in order to make a Nordic contribution towards solving the global climate crisis. The initiative comprises six sub-programmes, two of which will focus on climate change research. Nordic research collaboration is expected to contribute to responding to challenges in the management of climate change in northern regions. Finnish research teams are strongly represented in the new Nordic Centres of Excellence and research projects of the Top-level Research Initiative launched by the Nordic prime ministers. The Finnish teams studying permafrost in the project “Impacts of a changing cryosphere - depiciting ecosystem-climate feedbacks from permafrost, snow and ice” (DEFROST)” are headed by Pertti Martikainen (University of Eastern Finland) and Timo Vesala (University of Helsinki).
Pertti Martikainen, Maija Repo, Christina Biasi (University of Eastern Finland) and Matti Seppälä have investigated nitrous oxide emissions on subarctic palsa mires in northern Finland. Additionally, John Woodward (University of Northumbria, UK) and Matti Seppälä continued research in palsa mires, particularly remote sensing (laser scanning) of palsa mires in subarctic Finland. Recent findings on large nitrous oxide (N2O) emissions from permafrost peatlands have shown that tundra soils can support high N2O release, which is on the contrary to what was thought previously. However, field data on this topic have been very limited, and the spatial and temporal extent of the phenomenon has not been known. Martikainen and co-authors showed that unvegetated peat surfaces with high N2O emissions were very common in (sub)Arctic peatlands. Very high N2O emissions were measured from peat circles in northern Russia, whereas elevated, sparsely vegetated peat mounds at the same site had significantly lower N2O release. The N2O emissions from bare palsa surfaces in Northern Finland were highly variable but reached high rates, similar to those measured from the peat circles. All the vegetated soils studied had negligible N2O release. In the future, permafrost thawing may change the distribution of wet and dry surfaces in permafrost peatlands, which will affect N2O emissions.
In northern Finland, field work for Nordic project ‘Permafrost observatory in the Nordic Arctic: sensitivity and feedback mechanisms of thawing permafrost’ (2009–11) (Finnish participant J. Hjort from the Department of Geography, University of Oulu) was conducted in Vaisjeaggi palsa mire close to the Kevo research station. The main objectives of this project are to establish a permafrost monitoring network based on existing Nordic research stations and key research sites for assessing the effects of climate change on the permafrost environment and secondly to provide comparable data and new insight from these sites on the sensitivity and feedback mechanisms of thawing permafrost.
The project ‘Spatial modelling of periglacial processes under environmental change’ (2008–2011) (J. Hjort and M. Luoto (University of Oulu and University of Helsinki) continued. This project has focused on spatial modelling of periglacial processed based on remote sensing and GIS data. Additionally, Hjort and Luoto have investigated interaction of periglacial processes and ecologic features across altitudinal zones in subarctic landscapes. Moreover, Luoto has continued to investigate dynamics and the main drivers of recent changes in the Arctic vegetation. He has combined vegetation distribution models with periglacial process information in high-latitude landscapes. This project is part of the consortium Impacts of climate change on Arctic environment, ecosystem services and society (CLICHE) funded by the Finnish Research Programme on Climate Change (FICCA), Academy of Finland.
University of Helsinki organized in summer 2011 a graduate school “Global change modelling in high-latitude environments: integrating field sampling with global data”. One of the focus areas of the graduate school was permafrost and seasonal frost activity in northern environments in northern Finland and Norway (Figure below).
Permanently frozen peat hummocks (palsas) in subarctic mires in NW Finland, Iitto. Photography taken during the graduate school excursion “Global change modelling in high-latitude environments: integrating field sampling with global data”, August 2011
Geological Survey of Finland (T. Ruskeeniemi) investigated recharge of subglacial meltwaters into bedrock within the international Greenland Analogue Project (GAP) initiated by the Finnish (Posiva) and Swedish (SKB) nuclear waste management companies in collaboration with the NWMO from Canada. The research area is in Kangerlussuaq, west Greenland. A new 687 m deep bedrock drillhole extending beneath the ice margin was drilled in 2011. The hole was instrumented with subpermafrost groundwater sampling facility and for monitoring of pressure, temperature and the electrical conductivity of groundwater. Bedrock temperature profiling is provided by fiber optical cable technique (DTS). Moreover, Geological Survey of Finland (P. Lintinen and H. Vanhala) and Mining Geological Company MIREKO continued co-operation in the field of geophysical characterization of permafrost in Northern part of Komi Republic and Nenets Autonomous Region. This study started in 2007 after which three expeditions have been made to lowland permafrost targets and one (2011) to an Alpine permafrost area by Polar Urals.
Miska Luoto (firstname.lastname@example.org)