The Arctic is experiencing rapid climate change, with land surface temperatures in some northern regions reported to be increasing at double the global average rate. Increases in both temperature and atmospheric CO2 concentration, are causing changes in the structure, function and the species composition of vegetation in the Arctic that have not been seen before. The exact nature of these changes varies spatially, according differences in local environmental conditions and will affect different plant species in different ways. However, the sparsity of ground measurements in the arctic makes it difficult to predict how these changes in vegetation will manifest over larger spatial scales, and what the feedback implications will be for future climates.
Plants take up a large proportion of carbon dioxide from the atmosphere through photosynthesis, and any climate-induced changes in photosynthesis could either modulate or amplify increasing atmospheric CO2 concentrations. Recent developments in remote sensing methods and satellite technologies have opened up exciting new opportunities to use solar-induced fluorescence (SIF) and leaf biochemical estimates to model plant photosynthesis over large areas. However, we must first establish how well these techniques represent physiological variables at the leaf level, before we can scale up to satellite retrievals to investigate biome-scale changes in vegetation productivity. During our time in the Arctic, we’ll be taking coincident measurements of plant photosynthesis, leaf reflectance and chlorophyll fluorescence on different plant communities around Abisko, to answer address some of these questions.