Tully synthesis

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• Tully synthesis
• 1) Physics and patch dynamics
• 2) Physics and mixed layer depth
• 3) Nutrients and trace elements
• Phytoplankton response succession
• Foodweb bacteria
• Gases
• 7) Biogeochemistry

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Tully synthesis 1) Physics and patch dynamics
?
29 July
4 August
270 km2
E to W stretching (altered entrain- ment / loss
rates (chla/POC increases 22/24 July
N to S elongation
10 July 2002 (60 km2)

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Tully synthesis 1) Physics and patch dynamics

• Needed
• SeaWiFS images patch volume
• from pixels
• pCO2 from Tully
• Kaiyo-maru drifter buoys
• / Lagrangian ref, altimetry data
• Tully SF6 vs pCO2 relationship
• e) El Puma sigma t and patch spread

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  Drawdown of 6 umol Si by end of Tully
occupation, the strain rate ? gives a supply
0.5 µmol d-1 Si Estimated gross growth rate is
µ 0.13 0.08 0.21 d-1 Net phytoplankton
growth rate is 0.13, daily cell loss from patch
cente due to stirring is 38 Chl concentration
of 3 mg chl m-3 then gives Chlorophyll
production rate of 0.6 mg chl m-3 d-1   Si per
mol C (assuming steady state) gives a silicate to
carbon uptake ratio of Si/C 0.2 mol N/C 0.08
mol N per mol C Si/N 2.5 
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• Tully synthesis
• Physics and mixed layer depth
• b) Kaiyo/El Puma sigma t and Brunt-Vaisala
• Frequency
• c) Complete wind dataset shear estimates
• d) Compare drifter buoy estimates Tully
• And El Puma / Kaiyo-maru

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SERIES SF6 Vertical evolution
D2 D4 D6 D8
D10 D12 D14
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D2 D4 D6 D8
D10 D12 D14
D2 D4 D6 D8
D10 D12 D14
a) Patch volume estimates after Tully left SF6
plus those from pCO2
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• Tully synthesis
• 3) Nutrients and trace elements
• NO3 and Si time-series
• b) Integrated 0-75 m inventories
• Towards end of patch elevated
• N and Si
• c) Integrated Nut inventories effect
• Of shear (slippage)
• And shoaling of patch (sigma t)
• d) Fe budget
• e) Standarise Fe terms
• f) El Puma vs. Tully nutrients

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• Tully synthesis
• 4) Phytoplankton response succession
• Picophytos cell no change
• But most responsive to Fe supply
• b) Phaeocystis doubling in cell
• Then a crash in - grazing and/or
• Physiological shifts (mixed layer?)
• Single cell not colonial (?)
• intermediate response to Fe supply
• Oxidative stress ?
• c) Phaeophorbide ? Whos grazed?
• d) DMSP/DMS - Phaeo and/or
• Coccos?

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Chlorophyll vs. Flow cytometry data
Phaeocystis
Chlorophyte
Sm. diatom
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4) Phytoplankton response succession c) Diatoms
Low seed stock and Exponential increase in
chla (low Grazing) Fe supply initially not
receptive Damaged cells .. (low Fe uptake
Normalised to biomass) Si or Fe limited?
Timing of Reduced Fv/Fm linked to capacity
to Grow faster with more Fe Internal Fe pools
give several more Divisions? look at TDFe
levels Calculate Fe requirements Fe stress and
sinking rates/ TEPS 15N dataset
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Synecocchococcus responds to Fe
Phaeocystis increase
Diatoms respond to more Fe
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• 5) Foodweb bacteria
• Bact production
• Bacterivory
• Role in Fe budget
• 6) Gases
• DMS high IN and OUT
• HPLC pigments
• Cocco vs Phaeo timing
• Isoprene prod rates, budget and who is
  producing it?
• Methyl-Halides who is producing?
• N2O NH4/NO2 subsurf max
• CO maxima towards end of Tully
• Lysis rate Phaeophorbide
• El Puma datasets clues??

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Nitrification? Nitrite increase at 45m of 0.25
umol/l - N2O increase of 1 nmol/l Increase of
0.4 - comparable to 0.1-0.4 N2Onitrite product
ratio from nitrification
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• Biogeochemistry
• 15N signal (water, algae, traps)
• C, N, Si budgets
• Imbalances in budgets
• Depth of integration slippage
• Turnover rates (NH4 max)
• Remin length scales Si, C, N
• 100 125 m trap fluxes little
• Decrease
• Is the sub ML community primed for export events
  ? Teras/forams
• To come DOC/N/P, trap metals
• (IPCMS) 13C, 13CO2, Alkalinity

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July 12 to 28 0 to 75 m budget -376 mmol m-2 Si
240 mmol m-2 BSi 76 mmol m-2 Si
export missing 60 mmol m-2 (16)
Note one period of diatom growth.
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Particulate Si collected in drifting traps.
Note high loss rate between 50 and 75 m
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d15N dynamics of nitrate, phytoplankton, and
sediment traps