Monitoring Report M-1072 | 2018 Monitoring ocean acidification in Norwegian seas in 2017 MADE BY: Institute of Marine Research, Uni Research, Norwegian Institute for Water Research COLOPHON Executive institutions (the institutions are responsible for the content in the report) Institute of Marine Research, Uni Research, Norwegian Institute for Water Research Project manager for the contractor Contact person in the Norwegian Environment Agency Melissa Chierici Gunnar Skotte M-number Year Pages Contract number M-1072 2018 106 17078007 Publisher The project is funded by Norwegian Environment Agency Norwegian Environment Agency Author(s) Jones, E., M. Chierici, I. Skjelvan, M. Norli, K.Y. Børsheim, H.H. Lødemel, T. Kutti, K. Sørensen, A.L. King, K. Jackson, T. de Lange Title – English and Norwegian Monitoring ocean acidification in Norwegian seas in 2017/ Havforsuringsovervåking i norske farvann i 2017 Summary – Sammendrag This is the annual report from 2017 based on the program: ‘Monitoring ocean acidification in Norwegian waters’ funded by the Norwegian Environment Agency. The measurements are performed by the Institute of Marine Research (IMR), Norwegian Institute for Water Research (NIVA), and Uni Research (UNI), and the measurements cover the area from Skagerrak/North Sea in the south, through the Norwegian Sea, and the seasonally sea-ice covered northern Barents Sea. IMR conducted water column measurements along repeated transects, mainly during winter in the North Sea (Torungen–Hirtshals section), in the Norwegian Sea (Svinøy-NW and Gimsøy-NW sections), in the Barents Sea (Fugløya-Bjørnøya section and stations in the NE Barents Sea), and at Skrova and Arendal coastal stations. UNI conducted water column measurements at Station M, continuous surface measurements at the same site, and water column measurements at two coastal stations in Hardanger. NIVA performed surface water measurements on two sections; Oslo-Kiel (North Sea/Skagerrak) and Tromsø-Longyearbyen (Barents Sea opening) during all of 2017. This report shows and discusses some time series and trends for the period 2011-2017. Denne rapporten gjelder undersøkelser av havforsuring i 2017 utført av Havforskningsinstituttet (IMR), Norsk institutt for vannforskning (NIVA) og Uni Research (UNI) på oppdrag fra Miljødirektoratet. Måleområdet i rapporten går fra Skagerrak/Nordsjøen, gjennom hele Norskehavet og til nordlige deler av Barentshavet. IMR har gjort vannsøylemålinger, i hovedsak vinterstid, langs faste snitt i Nordsjøen (Torungen–Hirtshals), Norskehavet (Svinøy- NV og Gimsøy-NV), i Barentshavet (Fugløya-Bjørnøya og stasjoner i det nordøstlige Barentshavet), og ved Arendal og Skrova kyststasjon. UNI har gjort vannsøylemålinger gjennom store deler av året på Stasjon M i Norskehavet, kontinuerlige overflatemålinger på Stasjon M, og vannsøylemålinger på to kyststasjoner i Hardanger. NIVA har gjort overflatemålinger store deler av året på strekningen Oslo-Kiel og Tromsø-Longyearbyen. I denne rapporten presenteres og diskuteres tidsserier fra perioden 2011-2017. 4 Keywords 4 Emneord Carbonate system, interannual and seasonal Karbonmålinger, mellomårlig-og sesongs- variability, biogeochemical processes variasjon, biogeokjemiske prosesser Cover photo Photo: Kim Abel Tromsø, mai 2018 Authors: Elizabeth Jones*, Melissa Chierici*, Ingunn Skjelvan**, Marit Norli***, Knut Yngve Børsheim*, Helene Hodal Lødemel*, Tina Kutti*, Kai Sørensen***, Andrew Luke King***, Kristin. Jackson**, Tor de Lange** *Havforskningsinstituttet (IMR), **Uni Research (UNI), ***Norsk institutt for vannforskning (NIVA) This report should be cited: Jones, E., Chierici, M., I. Skjelvan, M. Norli, K.Y. Børsheim, H.H. Lødemel, T. Kutti, K. Sørensen, A.L. King, K. Jackson og T. de Lange. 2018. Monitoring of ocean acidification in Norwegian seas in 2017, Rapport, Miljødirektoratet, M-XXX|2018 Monitoring ocean acidification in Norwegian seas in 2017 | M-1072|2018 Content Content .......................................................................................................... 4 Summary ..................................................................................................... 5 Extended Norwegian Summary ........................................................................... 8 1. Introduction ............................................................................................... 11 2. Methods and Data......................................................................................... 13 2.1 Sampling and Variables ............................................................................ 16 2.2 Measurements of Total Alkalinity and Total Inorganic Carbon ............................. 17 2.3 pH Measurements................................................................................... 17 2.4 pCO2 Measurements ................................................................................ 18 2.5 Calculation of pH and Saturation State of Calcite and Aragonite ......................... 18 3. Results ...................................................................................................... 19 3.1 North Sea and Skagerrak .......................................................................... 19 3.1.1 Spatial variability along Torungen-Hirtshals section ................................. 19 3.1.2 Seasonal variability at Arendal station ................................................. 22 3.1.3 Seasonal variability in surface water ................................................... 24 3.1.4 Trend analysis at selected stations ..................................................... 28 3.2 Norwegian Sea ...................................................................................... 31 3.2.1 Spatial variability along the Svinøy-NW section ...................................... 31 3.2.2 Spatial variability along the Gimsøy-NW section ..................................... 34 3.2.3 Seasonal variability in open ocean ...................................................... 36 3.2.4 Seasonal variability in coastal water .................................................... 41 3.2.5 Trend analysis at selected stations ..................................................... 45 3.3 Barents Sea .......................................................................................... 52 3.3.1 Spatial variability along the Fugløya-Bjørnøya section .............................. 52 3.3.2 Spatial variability along the northeastern Barents Sea section .................... 55 3.3.3 Seasonal variability in surface water ................................................... 56 3.3.4 Trend analysis at selected stations ..................................................... 60 3.4 Norwegian Coast .................................................................................... 66 3.5 Cold Water Coral Reefs ............................................................................ 67 4. Summary and Recommendations ...................................................................... 69 5. References ................................................................................................. 71 6. Attachments ............................................................................................... 74 6.1 Plots .................................................................................................. 74 6.2 Data Tables .......................................................................................... 81 6.3 Definitions .......................................................................................... 104 4 Monitoring ocean acidification in Norwegian seas in 2017 | M-1072|2018 Summary This is the annual report from 2017 based on the program: ‘Monitoring ocean acidification in Norwegian waters’, which began in 2013 and is funded by the Norwegian Environment Agency. The report is based on measurements of AT, CT, pCO2 and pH made by the Institute of Marine Research (IMR), Norwegian Institute for Water Research (NIVA) and Uni Research (UNI) with updated data from 2017. IMR conducted water column measurements along repeated transects during winter and spring 2017 in the North Sea (Torungen–Hirtshals), at two sections in the Norwegian Sea (Svinøy-NW and Gimsøy-NW), and at two sections in the Barents Sea (Fugløya-Bjørnøya in February and April 2017, and in the northeastern Barents Sea in September 2017). The Norwegian Sea water column was also investigated by UNI which performed seasonal studies at Station M. Moreover, UNI also contributed with continuous surface pCO2 data at Station M. NIVA performed seasonal cruises (winter, spring, summer and autumn) for surface water measurements on two sections; Oslo-Kiel (North Sea) and Tromsø- Longyearbyen (Barents Sea opening) during 2017, and present data on both seasonal and interannual basis. In addition, the report includes data from monthly measurements at a coastal site in Skrova in Lofoten and Arendal in Skagerrak (IMR) and from two coastal sites in Hardanger (UNI). All sampling positions are shown in Figure 1. This report includes carbonate chemistry data and ancillary variables such as salinity, temperature, and inorganic nutrient concentrations to provide baseline observations of variability attributed to oceanographic and anthropogenic processes such as the influence of mixing of water masses, freshwater/meltwater inputs, CO2 emissions and oceanic uptake, and biological processes including production and respiration. For water column data, this is measured each year and the observed seasonal and interannual