Impacts of climate change on lake ecosystems in the Swedish arctic

The Arctic is warming faster than anywhere in the world. The Arctic also has a significant proportion of the freshwater and terrestrial organic carbon (C) stocks on the planet. Lakes are hotspots of greenhouse gas (CO2 and CH4) emissions and C storage.

As a result, the response of lakes to both direct and indirect effects of climate change will strongly influence arctic feedbacks to climate change.

A critical knowledge gap lies in our ability to make quantitative predictions of how the aggregated C fluxes of thousands of lakes that vary in size, shape, and landscape context will respond to projected climate change. However, lakes are not integrated into regional and global C cycle models.

The aim of the project is to forecast how direct and indirect effects of climate will change regional lake carbon cycling in the Swedish arctic.

By using a combination of novel large-scale lake survey, analyses and modeling, I will test the hypotheses that: 1) indirect (shifts in water and terrestrial carbon inputs) will have a stronger impact on lake climate feedbacks than direct (temperature) effects, and 2) small lakes will act as negative feedbacks for climate change through enhanced carbon burial, but large lake responses will accelerate climate change through increased greenhouse gas emissions.

The project aims to fill significant gaps in our knowledge of how lake ecosystems function at large-scales for understanding how climate will respond to the projected anthropogenic forcings.