1. Ocean Weather Station M - from weather forecast to climate monitoring Ingunn Skjelvan Bjerknes Centre for Climate Research and Geophysical Institute, University of Bergen M/S Polarfront

2. Start in 1948 Start in 1948 61 yrs with temperature and salinity, GFI, 5 t/w 56 yrs with oxygen, GFI, weekly 28 yrs with atmospheric greenhouse gasses, NOAA, 2 t/w 18 yrs with biological parameters, IMR, weekly 8 yrs with carbonate system, BCCR, monthly 4 yrs with sea and air pCO 2, BCCR, continuously 3 yrs with carbon isotopes, BCCR, monthly 3 yrs with direct flux/eddy correlation studies, NOC, continuously + moorings/sensors Non-meteorological time series

3. WARMER deep water during the last 25 yrs Annual mean temperature at 2000 m depth Østerhus 2009 Geophysical Institute, University of Bergen (GFI)

4. The recent warming is due to different processes Østerhus (2009), BCCR/GFI TEMPERATURE OXYGEN

5. INCREASING atmospheric CO 2 content INCREASING annual mean wave height Norwegian Meteorological Institute NOAA

6. INCREASING oceanic pCO 2 time pCO 2 ocean surface atmosphere 2000 m 10 m (winter values)  C T = +1.3  mol kg -1 yr -1 (~2.6 uatm yr -1 )  C T = +0.6  mol kg -1 yr -1 Bjerknes Centre for Climate Research (BCCR) DECREASING sink for atm CO 2 ~25 μmol kg -1 (~1.1 μmol kg -1 yr -1 ) ~9 μmol kg -1 (~0.4 μmol kg -1 yr -1 ) - changing deep circulation - anthropogenic origin

7. INCREASING ocean acidification -0.03 pH units over 6 years (-0.005 pH units/yr)

8. Findlay et al., 2008 OWSM carbon data used to verify models Coupled carbon- ecosystem model used to examine carbon and nutrient mixed layer dynamics

10. Aim: continuation of the long time series Aim: continuation of the long time series Moorings / buoys / sea gliders Moorings / buoys / sea gliders Ship time for water sampling and deployment / recovery Ship time for water sampling and deployment / recovery Future monitoring at OWSM pHpCO 2 1st application partly financed 2nd application pending

11. Major challenges Not enough time for overlapping measurements/calibrations Not enough time for overlapping measurements/calibrations

12. Appendiks

13. Decrease in surface-ocean pH is already measurable Anthropogenic decline in surface pH: 0.1 since 1750 (indirect method) 0.02 pH units per decade since 1980 (direct method) based on Bates, Dore, Gonzàles-Dàvila et al. in Willebrand, Bindoff et al. (IPCC AR4, 2007)

14. Spreading of Intermediate from the Greenland Sea Greenland Sea Norwegian Sea M

15. Recent warming Ice cover Arctic Ocean Greenland Sea Norwegian Sea Atlantic Ocean Cooling Heating Intermediate depth: Warming due to warmer water convected in Greenland Sea convection ~2000 M: Warming due to lack of GSDW (replaced by AODW) Below 2500 m: Warming due to geothermal driven convection and heating