Climate impact on sources and sinks of greenhouse gases in high-latitude lakes

Project description

Arctic and subarctic lakes play an important role in the global C cycle by burying C in sediments and emitting greenhouse gases as carbon dioxide and methane to the atmosphere. The relative magnitude of these different pathways has large implications for their role in the C cycle, i.e. to what extent they act as C sources or sinks. Still, the knowledge of C cycling in lakes is in many important aspects incomplete, preventing accurate quantification and predictions of their C source-sink function and response to climate change. The aim of the project is to assess climate impacts on C emission and burial in arctic–subarctic lakes. We will specifically investigate direct impacts by temperature and precipitation, and indirect impacts via changes in terrestrial surroundings, and how these various drivers influence the C source-sink function of lakes depending on the rate and magnitude of change. An important part is to assess the various sources and pathways underpinning emission and burial in lakes. The core of the project is made up of (i) comparative studies of lakes across gradients in temperature and precipitation and (ii) large-scale experimental test of responses in C emission and burial to increases in temperature and precipitation/runoff.