Long-term, integrated observations are essential for understanding how climate change affects Arctic hydrology and carbon cycling. Using nearly 30 years of harmonized data from the Greenland Ecosystem Monitoring programme across land, rivers, and coastal seas, this study examines interactions among warming, increasing precipitation, and local disturbances in regulating net ecosystem carbon balance. Records from Northeast Greenland show that extreme precipitation and snowmelt events can abruptly reduce CO₂ uptake, trigger thermokarst development, shift ecosystems from carbon sinks to sources, and greatly enhance riverine carbon export. Observations from Young Sound further reveal declining coastal nutrients and phytoplankton biomass linked to tundra greening and fresher, nitrate-poor runoff. Overall, the results demonstrate that hydrological extremes and disturbance-driven processes can outweigh gradual warming trends, highlighting the critical role of long-term monitoring for identifying land–river–coastal feedbacks in a rapidly changing Arctic.
Short bio:
Experienced researcher and teacher in climate change and arctic environmental issues. Research focuses on Arctic ecosystem ecology and trace gas biogeochemistry with special focus on carbon dioxide and methane exchange in northern terrestrial environments. Holds a PhD from the University of Cambridge and has carried out extensive research in Greenland, Alaska, Svalbard, Siberia and northern Sweden. Currently Scientific Leader of Zackenberg Research Station, NE Greenland and also the Greenland Ecosystem Monitoring Program. Affiliated with Aarhus University and University of Oulu.
Torben Røjle Christensen