1. Thoughts on thalassorheology
Thoughts on thalassorheology
Ian R. Jenkinson
杨海风
Institute of Oceanology, Chinese Academy of Sciences, Qingdao, People’s Republic of China
1st International RheFFO Workshop 1

2. Content
1. Viscosity (and elasticity) of seawater, particularly in algal blooms 2. Length scales-dependence in sewage sludge and in ocean water 3. Harmful algal blooms and gill “clogging” in fish 4. Phaeocystis and viscosity 5. Density discontinuities and thin layers. 6. Future prospects and collaboration.

3. Thalassorheology

4. Thalassorheology
Jenkinson (1993). Bulk phase viscoelastic properties of seawater Oceanologica Acta

5. Thalassorheology
Jenkinson & Biddanda (1995). Bulk phase viscoelastic properties of seawater: relationship with plankton components. Oceanologica Acta
Excess (biological) viscosity is positively related to chlorophyll concentration at a variety of scales (m to 1000 km)

6. Jenkinson (1993). Viscosity and elasticity of Gyrodinium cf
Jenkinson (1993). Viscosity and elasticity of Gyrodinium cf. aureolum and Noctiluca scintillans exudates in relation to mortality of fish and damping of turbulence. In Smayda, T., Shimizu and Y. (eds), Toxic Phytoplankton Blooms in the Sea, Elsevier, pp
Rheological properties of a culture of 4.4 cells µL-1 of Karenia mikimotoi (syn: Gyrodinium cf. aureolum). Excess viscosity E ( )and elastic modulus G' are plotted against shear rate . G' was found to be between 10% and 50% of excess viscous modulus, G"E = E . .

7. Thalassorheology
Jenkinson, Claireaux, Gentien (2007). Biorheological properties of intertidal organic fluff on mud flats and its modification of gill ventilation in buried sole, Solea solea. Marine Biology
Yield hold-up pressure (Pa)
In sewage sludge, yield hold-up pressure is proportional to (capillary diameter)D In this case, D was found to be about -2

8. Thalassorheology
Spinosa & Lotito’s (2003) (SL) measurements on sewage sludge.
SL found yield hold-up pressure h to be proportional to (capillary diameter)D, where D was about -2.
Other things being equal, shear stress at the capillary wall ~h.(diameter)-1
So the yield stress of the sludge was proportional to h.(diameter)d
where d = D - (-1), that is about -1.

9. Our proposed rheological model for seawater and phytoplankton cultures
 is dynamic viscosity
W is aquatic component of 
E is EPS component of 
is shear rate
Phyto is phytoplankton concentration
k is an empirical coefficient
P, Q ,d are the shear rate, phytoplankton and length scale exponents
Explanation
Viscosity consists of
aquatic viscosity + EPS viscosity
EPS viscosity depends on - amount and type of phyto and its EPS
- shear rate
- length scale of your interest  
d is highly negative - Very “Fractally Lumpy” d = Perfectly Smooth

10. Thalassorheology
Jenkinson, Shikata & Honjo (2007) Harmful Algae News.

11. Thalassorheology
Jenkinson, Shikata & Honjo (2007) Harmful Algae News.
We found non-Newtonian properties (a yield stress) in a culture of the harmful alga, Chattonella antiqua, at the scales involved in flow of water through fish gills.

12. Thalassorheology
For a review of thalassorheology (the rheology of natural waters), see:
Jenkinson & Sun (2010) Rheological properties of natural waters with regard to plankton thin layers. A short review. Journal of Marine Systems, 83, 12

13. Seuront & Vincent (2008), Marine Ecology Progress Series Swimming trajectories of copepod Temora longicornis in Phaeocystis globosa bloom water.(English Channel, French side)
Before bloom
Before foam formation
After foam formation
After bloom 13

14. Seuront & Vincent (2008), Marine Ecology Progress Series Interpretation.
Before bloom
Before foam formation
After foam formation
After bloom 14

15. Pycnoclines and thin layers
Alldredge et al. (2002) Marine Ecology Progress Series

16. Alldredge et al. (2002) Marine Ecology Progress Series

17. Pycnoclines and thin layers
Alldredge et al. (2002) Marine Ecology Progress Series

18. Yellow Sea (August 2001) China Korea
Zhang et al (2007) Journal of Plankton Research
Yellow Sea (August 2001)
China
Korea
Yellow Sea Cold Bottom Water
Temperature
1-1 to 1-9
Vertical distribution of temperature

19. Jenkinson & Sun, (2011). A model of pycnocline thickness
For a model of how thalassorheological properties may be changing pycnocline characteristics through effects of viscosity on the relationship between inertial and viscous effects,
the Richardson number,
see:
Jenkinson & Sun, (2011). A model of pycnocline thickness
modified by the rheological properties of phytoplankton exopolymeric substances. Journal of Plankton Research. 19

20. Jenkinson & Sun, (2011). Journal of Plankton Research.
Our model shows that whether phytoplankton exopolymeric substances will control pycnocline dynamics will depend on a length-scale exponent of thickening d.

21. Jenkinson & Sun, (2011). Journal of Plankton Research.
Our model shows that whether phytoplankton exopolymeric substances will control pycnocline dynamics will depend on a length-scale exponent of thickening d.
d is highly negative - Very “Fractally Lumpy” d = Perfectly Smooth

22. Jenkinson & Sun, (2011), Journal of Plankton Research.
Our model shows that whether phytoplankton exopolymeric substances will control pycnocline dynamics will depend on a length-scale exponent of thickening d.
We investigated d in our project funded by the Chinese Academy of Sciences.

23. Measured viscosity by measuring flow rate as a function of hydrostatic pressure difference h and capillary radius using a modified Ostwald-Ubbelohde viscoscometer (OUV).

24. Measured viscosity by measuring flow rate as a function of hydrostatic pressure difference h and capillary radius using a modified Ostwald-Ubbelohde viscoscometer (OUV).
Thus, shear rate at the wall was calulated as a function of both shear stress at the wall and length scale.

25. Measured viscosity by measuring flow rate as a function of hydrostatic pressure difference h and capillary radius using a modified Ostwald-Ubbelohde viscoscometer (OUV).
Thus, shear rate at the wall was calulated as a function of both shear stress at the wall and length scale.
Measurements were replicated 10 times and expressed in comparison with pure seawater or Miili-Q water, also replicated 10 times.

26. Measured viscosity by measuring flow rate as a function of hydrostatic pressure difference h and capillary radius using a modified Ostwald-Ubbelohde viscoscometer (OUV).
Thus, shear rate at the wall was calulated as a function of both shear stress at the wall and length scale.
Measurements were replicated 10 times and expressed in comparison with pure seawater or Miili-Q water, also replicated 10 times.
The capillary of the OUV was replaced by a module of capillaries of one of 5 radii, 0.35, 0.5, 0.75, 1.05 and 1.5 mm.

27. Qingdao, 2010 Differential pressure sensor

28. Qingdao, 2010 Differential pressure sensor
Differential pressure probe

31. Yield stress tube

32. Replaced by rigid vertical tubes!

33. The harmful plankton alga Karenia mikimotoi is an unarmoured dinoflagellate that specializes in living in density discontinuities in stratified parts of temperate, coastal seas around the world.

34. Seawater Karenia mikimotoi 6323 cells.mL-1

35. Seawater Karenia mikimotoi 6323 cells.mL-1

36. Seawater Karenia mikimotoi 6323 cells.mL-1

37. Seawater Karenia mikimotoi 6323 cells.mL-1

38. Seawater Karenia mikimotoi 6323 cells.mL-1

39. Reference seawater K. mikimotoi r = 0.35 mm r = 1.5 mm
Curves of log(P) vs time in K. mikimotoi culture (a, c) and its corresponding reference seawater (b, d) in capillaries of radius 0.35 mm (a, b) and 1.5 mm (c, d). This figure illustrates the ranges of data used to calculate total viscosity relative to seawater (relative viscosity) shown in Fig. 5.
Reference seawater
K. mikimotoi
r = 0.35 mm
r = 1.5 mm

40. Experimental materials

41. Total (laminar + turbulent) viscosity  in different cultures (a-f) relative to corresponding reference water. It is shown for the high-P (500 to 100 Pa) and low-P (100 to 20 Pa) ranges of hydrostatic pressure difference. A relative viscosity of 1 indicates no difference from reference water. Error bars are  SD. O – no sig. diff; + - sig. diff. P < 0.1; * - sig. diff. P < No. of replicates mostly 10 (7-11) for both experimental samples and reference water.

42. Ian R. Jenkinson and Jun Sun 杨海风 孙军
Thalassorheology: Biopolymer component of seawater viscosity depends on shear rate and length scale. Validating s model of how these polymers control ocean density stratification and mixing
Ian R. Jenkinson and Jun Sun
杨海风 孙军
Institute of Oceanology, Chinese Academy of Sciences, Qingdao, People’s Republic of China 42

43. Ian R. Jenkinson and Jun Sun 杨海风 孙军
Thalassorheology: Biopolymer component of seawater viscosity depends on shear rate and length scale. Confirm results and investigate the mechanism of the laminar drag reduction found?
Ian R. Jenkinson and Jun Sun
杨海风 孙军
Institute of Oceanology, Chinese Academy of Sciences, Qingdao, People’s Republic of China 43

44. Turbulence and the microbial loop
The European Regional Seas Ecosystem Model (ERSEM) has been coupled with the General Ocean Turbulence Model
(GOTM) to create a 1-D representation of a seasonally stratified site in the North Sea.

45. General Ocean Turbulence Model (GOTM)
GOTM is a one-dimensional water column model for marine and limnological applications. It addresses vertical turbulent mixing.
It links into 2-D and 3-D circulation models.
The co-ordinators of GOTM are keen to incorporate rheology into
GOTM.
We are co-ordinating with the fluid-mud engineers who are also incorporating rheology into physical models of circulation, and into GOTM

47. General Ocean Turbulence Model (GOTM)
General Ocean Turbulence Model (GOTM) is an ambitious name for a one-dimensional water column model for marine and limnological applications. It addresses vertical turbulent mixing.
It links into 2-D and 3-D circulation models.
The co-ordinators of GOTM are keen to incorporate rheology into
GOTM.
We are co-ordinating with the fluid-mud engineers who are also incorporating rheology into physical models of circulation, but we are pushing to add length-scale dependence, d, (for us and them!).

48.
Apparatus suggested at Galway (2009) Modeling Workshop on HABs and Thin Layers

49. Conclusions 1.
2. Rheological properties and density of EPS + ballasting materials determine vertical flux in the biological pump of organic matter (CO2 removal from surface layer and and low O2 zones at depth).
3. “Phyto” term in (1) implies generally highest effects in high-biomass algal blooms. (But bacterial EPS may also be important.)
4. EPS rheology may be modifying pycnocline dynamics. (Depends a lot on d). 5. We are liasing with fluid-mud workers and numerical modellers of ocean turbulence to put rheological properties into models of water-column structure and turbulence.

50. Conclusions
6. We are investigating d at IOCAS, partly to validate our model
of pycnocline bio-control .
Further results now in
Jenkinson, I. R. & Sun, J A model of pycnocline thickness
modified by the rheological properties of phytoplankton exopolymeric substances
Journal of Plankton Research, 33,
Jenkinson, I. R. & Sun, J Drag increase and drag reduction found in phytoplankton and bacterial cultures in laminar flow: Are cell surfaces and EPS producing rheological thickening and a Lotus-leaf Effect? Deep Sea Research II, 101,
Jenkinson, I. R., Sun, X. X. & Seuront, L. in press. Thalassorheology, organic matter and plankton: towards a more viscous approach in plankton ecology Journal of Plankton Research,

51. Merci!