Predictions of the impact of global and climate changes in the oceans requires time-series data to detect internal variability, build realistic scenarios as well as parametrize and validate models. The Arctic ocean is subject to high rates of ocean warming and acidification, which has critical implications for marine organisms, ecosystems, and ecosystem services. Yet, only few measurements of the carbonate system have been performed in the Arctic Ocean and they are spotty both in space and in time. Notably, there is no time-series station measuring the carbonate chemistry in this region, particularly in coastal waters. In its 2013 assessment, the Arctic Monitoring and Assessment Programme (AMAP) stated “It is of paramount importance that long-term, dedicated marine carbonate system observation programs are developed”.

The Alfred Wegener Institute for Polar and Marine Research (AWI) together with the Helmholtz Centre for Coastal Research Geesthacht (HZG) and the French Polar Institute (IPEV) teamed up in 2015 to establish the first time-series of carbonate system parameters in the coastal Arctic (AWIPEV-CO2). This station, located at Ny-Ålesund (Spitsbergen) at 12 m depth, benefits from a lot of ancillary data from the AWIPEV FerryBox (http://bit.ly/2Dzqjsg). The following parameters have progressively been added in the past three years: discrete total alkalinity and dissolved inorganic carbon (once a week), pCO2 (every min), in situ and FerryBox pH (every min), and discrete spectrophotometric pH (once a month to calibrate the sensors). There are also attempts to get high frequency measurements of total alkalinity (every 90 min). Data are available in near-real-time (http://bit.ly/2DwByln).

This presentation will provide a broad overview of the challenges involved with Arctic time-series and will provide information on four key questions this data set could help answer: (1) What is the seasonal variability (there are very few winter data in the Arctic)?; (2) What is the rate of acidi?cation in a high Arctic fjord ?; (3) What are the combined effects of changes in the carbonate chemistry, temperature and salinity on the calcium carbonate saturation state?; (4) What is the annual balance of air-sea-CO2 ?uxes?