Post on 17-May-2018
Challenges in modelling benthic nutrient fluxes- the importance of observations
Elin Almroth Rosell, SMHIHELCOM-EUSBSR workshop, 28-29 November 2017
RCO-SCOBIRossby Centre Ocean modelSwedish Coastal and Ocean BIogeochemical model
3D- model
model domain: the Baltic Sea
High horizontal resolution (2 nm)and 83 vertical levels
Model setup
Sweden
Norway Finland
A new approach to model oxygen dependent benthic phosphate fluxes in the Baltic SeaElin Almroth-Rosell, Kari Eilola, Ivan Kuznetsov, Per O.J. Hall and H.E. Markus Meier. Journal of marine systems 144 (2015) 127-141
Phosphate and oxygen in bottom water
Central Baltic Sea: SHARK data. Observations (150-190 m)
PO4 µmol/L
Oxygen and H2S as ”negative oxygen” (ml/L)
The data are collected from; 1) Viktorsson et al., 2012 .; 2) Laima et al., 2001; 3) Koop et al., 1990; 4) Conley et al., 1997; 5) Pitkänen et al., 2001; 6) Hille et al., 2005; 7) Graca et al., 2006 ; 8) Lehtoranta and Heiskanen, 2003. The different study sites are: 1, 4, 5, 8: Gulf of Finland 2: North east Germany 3: Northern Baltic Proper 6: Baltic Proper 7: The Gulf of Gdansk
K. Eilola et al. / Journal of Marine Systems 75 (2009) 163–184
Background
Adsorption mechanism:
Phosphateadsorb on Fe(III)oxides.
PBT BIP
WIP OrgP water PO4 water
SIN
KIO
P
PBTOUTBIP
BURIALPBT BURIALBIP
SED
PLO
SS
SED
IPLO
SS
Mineralization
PBTO
UT P
O4
SCAV
PO4
LIBP
PO4
SIN
KIIP
SCOBI news - Phosphorus dynamics
Cai and Sayles, 1996
[O2]BW OPD
Oxygen penetration depth
Validation of Benthic Phosphorus and Nitrogen in the Swedish Coastal zone
Model (SCM) and a Model Implementation of
MicrophytobenthosIvo Hoefsloot
MSc guided research Utrecht University – SMHISupervisors: Elin Almroth-Rosell1, Moa Edman1, Caroline Slomp2
1 Swedish Meteorological and Hydrological Institute, Göteborg, Sweden
2 Utrecht University, Utrecht, The Netherlands
9
99
Collected dataSource Type Area P samples N samples Period Comments(Malmaeus and Karlsson, 2012)
Publication Stockholm Archipelago
26 0 2008-2010
(Rydin et al., 2011)
Publication Stockholm Archipelago
4 0 2008
(Puttonen et al., 2014)
Publication Stockholm Archipelago
253 0 2008-2012
(Ekeroth et al., 2016)
Publication Stockholm Archipelago
4 4 2010-2013
Caroline Slomp
Personal comm.
Stockholm Archipelago
3 3 2015
Magnus Karlsson
Personal comm.
Stockholm Archipelago
65 0 2008-2009
SGU Database Stockholm Archipelago
71 0 1996-2010
Unknown water depth in all samples
Stockholm Vatten
Report Stockholm Archipelago
25 24 2007
SMHI-Sharkweb
Database Sundsvall Bay/ Ångermans-älven
296 296 2003-2011
Unknown water depth in 104 samples
Data collection from literature, databases (SGU, SHARKWEB)
Criteria: water content, coordinates, depth in sediment
Low amount of available data
Not enough N data in the Stockholm area
Conclusion Validation data for modelling and model developement are of
great importance, both in time and space
Don’t compare apples and pears! To be able to compare observations and model data the data need to have the same unit, which might only be possible if alsoother parameters are measured such as water content or porosity.
How to know what to measure? Communication
Mineral-bound phosphorus dynamics
Central Baltic Sea: SHARK data. Observations (150-190 m)
PO4 µmol/L
Oxygen and H2S as ”negative oxygen” (ml/L)
Forward
Jilbert et al. (2011), Fig. 4b
Arkona Basin station BY2. Solid line: September 2009Dashed line: June 2007
Seasonal variability Oxygen
Porewater profiles: Fe2+ and HPO42- Solid phase profiles: Fe-P.
Faeces Excretion
NH4
PO4
NBT
ND
PD
A1 A2 A3
O2
H2S
N2
Ni
Nitrogen fixation
Assimilation
Phytoplankton sinking Detritus sinking
Grazing Grazing
Mortality
Decomp
Decomp
Predation
Sedimentation
Resuspension
To lower layer To lower layer
Burial
Decomp
Decomp
Nitrification
Denitri- fication
ZOO
Inorganic P Resuspension
BIP
PBT IPW
Nitrification NO3
Denitrification
SCOBI news – Swedish Coastal and BIogeochemical model
RCO-SCOBIRossby Centre Ocean modelSwedish Coastal and Ocean BIogeochemical model The model domain covers the
Baltic Sea
• horizontal resolution of 3.7 km (2 nautical miles)
• 83 vertical levels • layer thicknesses of 3 m• maximum depth amounts to 249
m.
Model setup
Sweden
Norway Finland
In this study the main focus has been on the Baltic proper, during the period 1980 to 2008.
A new approach to model oxygen dependent benthic phosphate fluxes in the Baltic SeaElin Almroth-Rosell, Kari Eilola, Ivan Kuznetsov, Per O.J. Halland H.E. Markus Meier. Journal of marine systems 144 (2015) 127-141
Evaluation, model results
Basin nameNoSocc
NoSYears
A Sandöfjärden 209 23B Kanholmsfjärden 206 23C Solöfjärden 213 23D Trälhavet 215 23E S. Vaxholmsfjärden 131 23F Stora Värtan 141 23G Strömmen 249 23H Baggensfjärden 173 20
Biogeochemical reactor
1. External nutrient input.
2. Internal nutrient cycling and biogeochemical processing.
3. Internal nutrient removal.
4. Nutrient export.
Energy
Nutrient exportNutrient and oxygen supply
Life in the sea
Modeling theBiogeochemical reactor
1. Assume: e.g. initial conditions.
• Assume there is potential for life (live organic matter)
2. Idealize: e.g. model the most important known processes.
• How do we decide which processes we should include?
Energy
Nutrient exportNutrient and oxygen supply
Life in the sea