Major challenges are to estimate the Arctic Greenhouse gas budget and address inadequacies in river discharge observations
The Arctic and boreal land surface is home to a wide range of coupled processes with major feedbacks on the Earth System that have significant societal effects on the vulnerable economies of northern latitudes and Europe’s welfare. A major challenge is to estimate the Arctic greenhouse gas (GHG) budget. The current focus has been on measuring the two major carbon species CO2 and CH4 , however the existing network is still too sparse and most records are too short for differentiating interannual variability from long-term trends in GHG exchange processes. Therefore it is crucial to maintain and improve the station network to measure both CO2 and CH4 in key ecosystems and across all seasons.
For changes in the hydrological regime and river discharge to the Arctic ocean, the key need is to address inadequacies in the current network of in situ river discharge observations. About 30% of the drainage basin is ungauged, so we must exploit the existing data to estimate discharge from such areas through modelling or spatio-temporal interpolation methods.