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Research projects
PALAEO:
Climate change is arguably the greatest environmental challenge facing mankind. Robust predictions of the impacts of climate change and the development of appropriate socio-economic responses depend on a better understanding of the global carbon cycle. Many aspects of the cycle are already well constrained, but some elements remain highly uncertain, particularly the role of fresh waters. Arctic and boreal landscapes, with their exceptional abundance of shallow lakes, play a key role in the global carbon cycle. In fact, it is now evident that the role of fresh waters in the global carbon cycle, in particular as significant sources of greenhouse gases, has been severely underestimated, with present estimates limited by the sparse data. Global circulation models agree that future warming and precipitation trends will be amplified at high northern latitudes, with the most severe increases in the Arctic followed by boreal then temperate regions. The predicted changes will strongly affect the physical and chemical characteristics of lakes, as temperatures rise, and more nutrients and allochthonous (i.e. terrestrial) organic material will be transported into the lakes. How this will affect lakes as potential sources of greenhouse gases to the atmosphere is a crucial question, with potential for positive feedbacks.
The PALAEO project aims to provide completely novel insights into the long-term dynamics of methane concentrations and emissions from lakes in response to past climatic variation and anthropogenic impact. Lakes are an important component in the global carbon budget and their role as major sources of greenhouse gases, particularly methane, has long been underestimated. This is partly due to the absence of long-term data sets of methane emissions from lakes, which makes predictions and modelling of lake ecosystem responses to future climate change extremely difficult. PALAEO will combine a unique experimental system, contemporary field observations and state-of-the-art palaeolimnology to develop, validate and apply methods to track long-term dynamics in methane in lakes. The different spatial and temporal scales are linked by a consistent methodology using stable isotope analysis applied to chitinous invertebrate remains, which have the potential to reflect past methane concentrations in the water. Sediment cores from the Arctic (Greenland), boreal (Finland) and temperate (Denmark) regions will be analysed. These cores also provide information on past environmental and ecological conditions, such as temperature, nutrient levels and community structure. Sampling from regions that have shown large climate variations (Arctic, boreal) and highly variable degree of human impact (boreal, temperate) will provide unique data for modelling how methane emissions from lakes will be affected under future warming scenarios. In addition, these data will allow the assessment of the relative importance of multiple pressures (climate warming, eutrophication) in driving the increases of methane emissions from lakes in different regions. This makes PALAEO a highly novel study linking change in the environment and ecosystem structure to long-term change in a key ecosystem process with global significance – methane production and emission.
Climate change is arguably the greatest environmental challenge facing mankind. Robust predictions of the impacts of climate change and the development of appropriate socio-economic responses depend on a better understanding of the global carbon cycle. Many aspects of the cycle are already well constrained, but some elements remain highly uncertain, particularly the role of fresh waters. Arctic and boreal landscapes, with their exceptional abundance of shallow lakes, play a key role in the global carbon cycle. In fact, it is now evident that the role of fresh waters in the global carbon cycle, in particular as significant sources of greenhouse gases, has been severely underestimated, with present estimates limited by the sparse data. Global circulation models agree that future warming and precipitation trends will be amplified at high northern latitudes, with the most severe increases in the Arctic followed by boreal then temperate regions. The predicted changes will strongly affect the physical and chemical characteristics of lakes, as temperatures rise, and more nutrients and allochthonous (i.e. terrestrial) organic material will be transported into the lakes. How this will affect lakes as potential sources of greenhouse gases to the atmosphere is a crucial question, with potential for positive feedbacks.
The PALAEO project aims to provide completely novel insights into the long-term dynamics of methane concentrations and emissions from lakes in response to past climatic variation and anthropogenic impact. Lakes are an important component in the global carbon budget and their role as major sources of greenhouse gases, particularly methane, has long been underestimated. This is partly due to the absence of long-term data sets of methane emissions from lakes, which makes predictions and modelling of lake ecosystem responses to future climate change extremely difficult. PALAEO will combine a unique experimental system, contemporary field observations and state-of-the-art palaeolimnology to develop, validate and apply methods to track long-term dynamics in methane in lakes. The different spatial and temporal scales are linked by a consistent methodology using stable isotope analysis applied to chitinous invertebrate remains, which have the potential to reflect past methane concentrations in the water. Sediment cores from the Arctic (Greenland), boreal (Finland) and temperate (Denmark) regions will be analysed. These cores also provide information on past environmental and ecological conditions, such as temperature, nutrient levels and community structure. Sampling from regions that have shown large climate variations (Arctic, boreal) and highly variable degree of human impact (boreal, temperate) will provide unique data for modelling how methane emissions from lakes will be affected under future warming scenarios. In addition, these data will allow the assessment of the relative importance of multiple pressures (climate warming, eutrophication) in driving the increases of methane emissions from lakes in different regions. This makes PALAEO a highly novel study linking change in the environment and ecosystem structure to long-term change in a key ecosystem process with global significance – methane production and emission.
