Arctic-IPY programmes
Arctic Biosphere-Atmosphere Coupling across multiple Scales (ABACUS)
Disruption in the global carbon cycle is causing climate warming. The Arctic is already warming significantly, and warming is expected to be fastest and greatest at high latitudes, 4-7°C over the next century.
However, there are complex links among climate, the carbon cycle and the global energy balance which mean that the details of such global changes remain poorly understood.
We propose a major, linked programme of plant and soil studies, atmospheric measurements, aircraft and satellite observations, and modelling, to improve our understanding of the response of the arctic terrestrial biosphere to climate change. Our overall aim is to determine what controls the variability, in both time and space, of carbon, water and energy exchange between arctic ecosystems and the atmosphere.
Our field sites are based at Abisko, Sweden (with one focus area in dry tundra, the other in birch forest), and Kevo, Finland (with one focus on wet tundra, the other on dry tundra). At Kevo and Abisko both satellite imagery and aircraft flights will encompass an area of 10 km x 10 km, including both focus areas.
The project has the following work packages:
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WP1 Studies on plant allocation and phenology, and respiration-production ratios for major community types (via harvests, root measurement and isotope tracer experiments).
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WP2 Turnover of litter, soil organic matter (SOM), landscape distribution of soils (via soil surveys, isotope labelled litter, bomb carbon dating to determine SOM age), methane emissions.
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WP3 Chamber measurements of carbon and water exchanges from soils and vegetation at fine scales (a resolution of ~1m).
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WP4 Continuous tower measurements of carbon dioxide and water exchange between the soils/vegetation and the atmosphere at scales of ~100 m, and records of snow depth, soil moisture and climate.
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WP5 Aircraft measurements over the two study regions, recording carbon dioxide and water exchanges and images of the land surface and profiles of methane. These measurements will extend over areas of many square kilometres.
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WP6 Earth Observation via satellites. We will link observations from several satellite instruments to measurements of plant cover recorded in field campaigns.
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WP7 We use models to connect the information connected at different time and space scales. The models represent our best understanding of the system, and we check and improve our understanding against independent observations, whether from chambers, towers, aircraft or satellites. We test whether we can understand the data from satellites and aircraft in terms of the detail recorded at the chambers and towers and with the WP1 and WP2 experiments.
