Thirty years of nutrients and biogeochemistry in the Norwegian, Greenland and Iceland Seas, 1990-2019.

This dataset contains biogeochemical samples analyzed by the Plankton Chemistry Laboratory at the Institute of Marine Research (IMR), from the Norwegian, Greenland and Iceland Seas. Number of surveys and stations have varied greatly over the last 3 decades. IMR is conducting one annual Ecosystem Survey in April-May each year, with multiple trawl surveys and net tows, but only CTD water collections are reported here. This month-long exercise also has companion vessels from Iceland and the Faroe Islands surveying their own territorial waters. Three transects are the core of the time-series, visited multiple times each year (Svinøy-NorthWest, Gimsøy-NorthWest, Bjørnøya-West). On each station, the CTD cast is sampled for dissolved inorganic nutrients (nitrate, nitrite, phosphate, silicate) and phytoplankton chlorophyll-a and phaeopigments (ChlA, Phaeo) at predetermined depths. At times, short-term projects have collected samples for Winkler dissolved oxygen titrations (DOW) and particulate organic carbon and nitrogen (POC, PN) determinations. This unique data set has seen limited use over the years but is a great contribution towards global ocean research and climate change investigations.

Thirty Years of Nutrient Biogeochemistry in the Barents Sea and the adjoining Arctic Ocean, 1990-2019.

This dataset contains biogeochemical samples from the Barents Sea and Arctic region analyzed by the Plankton Chemistry Laboratory at the Institute of Marine Research (IMR). Number of surveys and stations visited in the Barents Sea and Arctic has varied over the last 30 years. One major effort is the annual Ecosystem Survey in the fall, with multiple trawl surveys, net tows and CTD water sampling. Additionally, two transects are visited multiple times each year (Fugløya-Bjørnøya and Vardø-North). Only samples collected from water bottles are reported here. Bottle samples from each CTD cast were collected for dissolved inorganic nutrients (nitrate, nitrite, phosphate, silicate) and phytoplankton chlorophyll-a and phaeopigments (ChlA, PHAEO) at predetermined depths and for later analysis at IMR. On occasion, short-term projects have performed Winkler dissolved oxygen titrations (DOW) and particulate organic carbon and nitrogen (POC, PN) determinations. This unique data set has seen limited use over the years but is a great contribution towards global ocean research and climate change investigations.