annual meeting, june 15-16 2015, istanbul, turkey wp2: results and criticalities in the north sea...
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Annual Meeting, June 15-16 2015, Istanbul, Turkey
WP2: Results and criticalities in the North
Sea
EMODnet Chemistry
Regional leader: Aarhus University, AU-DCE
Martin M. Larsen, DIVA by Jonas Kofoed Rømer
Annual Meeting, June 15-16 2015, Istanbul, Turkey
Data contibuters:
Current status
EDMO CODE NOx PO4 SiO
28 (CEFAS) 990 988 985
32 (The Environment Agency (EA)) 48 17 53
43 (BODC) 235241 283762 218896
486 (IFREMER) 838 948 956
545 (SMHI) 19377 23959 16041
612 (Norwegian Marine datacenter)8605 8605 8604
681 (RIHMI-WDC)103 503 127
729 (AU-DCE) 62762 62973 50141
1503 (was iFBM, Hamburg uni.)80 80 0
1578 (was MUMM-BMDC)2135 2043 2078
1725 (FMI)14 14 14
2135 (Marine Scotland institute)7264 7269 6667
Annual Meeting, June 15-16 2015, Istanbul, Turkey
General overview of the data contribution:
Current status
NOx PO4 SiO
Total CDI’s (CTD+Nutrients) 640531 640531 640531
Individual nutrients 346555 400535 309421
All nutrients available 263916 263916 263916
Spatial distribution:
- No data from Baltic- Area restricted to“central North Sea”- NOx=NO2+3 or
NO3+NO2 or NO3
Annual Meeting, June 15-16 2015, Istanbul, Turkey
The worst case dataset
SiO dataset
Annual Meeting, June 15-16 2015, Istanbul, Turkey
DIVA production:Topography problems
• Gebco 2014 30 arc-seconds bathymetry used for contours (raises The Netherlands to +1 instead of underwater)
• Too finescaled, so only every 6th grid used
Depths used: 500, 100, 75, 50, 25, 20, 10, 5, 1 and 0.
4 Seasons: Winter 1101, spring 0204, summer 0507, autumn 0810.
46 Decades: one-year interval 1960 – 2006 (+10 years)
Interpolation settings: CL=0.7, SNR= 1.0 Ref. field CL=3, SNR=0.1
Annual Meeting, June 15-16 2015, Istanbul, Turkey
NOx Vinter-spring
Summer-autumn
Annual Meeting, June 15-16 2015, Istanbul, Turkey
NOx conclusions:
Generally too few data in the central North Sea
• The first ”red” areas occurs around 1980 at Odense Fjord and in the Baltic [where no data should be available!]
• From mid 1980ies, full data coverage for 10 year periods [except winter months]
• Most coastline with river output red from 1990ies onward, nutrient rich stream along jutlandic coast from German Bight
• Winter and Autumn have the fewest datapoints, and hence the largest area with >0.5 relative error theshold
• Usually not NOx controlled system in the North Sea
Annual Meeting, June 15-16 2015, Istanbul, Turkey
PO4 Vinter-spring
Summer-autum
Annual Meeting, June 15-16 2015, Istanbul, Turkey
PO4 conclusions:
Winter data
• First yellow data in Bay of Aarhus, then the Channel
• Generally very low numbers in the central North Sea
• Generally more data available, but seems like more missing data than for NOx in the central/british side of the North Sea
• Less pronounced river inputs (except Thames, Holland)
Annual Meeting, June 15-16 2015, Istanbul, Turkey
SiO Vinter-sping
Summer-autumn
Annual Meeting, June 15-16 2015, Istanbul, Turkey
SiO conclusions:
Patterns not as clear cut from rivers as NOx and PO4
• Some increase in Bay of Aarhus and in the Channel
• Not so much from German rivers
• Generally significant less data and more areas masked due to high error.
Rerun of winter nutrients with new DIVA version (?)
- Check timetrend more thoroughly
- Portal upload. We need password for the ocean browser portal + xml metadata creation using divadoxml-gui.
- No logit transform used yet, we have some negative values in the interpolated results. Should we logit transform?
Run DIVA for O2 and Chlorophyll data
Check if enough Hazardous substance data to perform DIVA interpolation
– No seasonality for sediment/biota samples
– maybe on CHASE output to get highest possible spatial output for combined matrices
Border problems with the Baltic (perhaps other areas?) + Baltic data?
Annual Meeting, June 15-16 2015, Istanbul, Turkey
Planning for the last year