2007-01 STF - Geleynse - RBR.pdf

Why Salinometry?Salinity is a key property of seawater from whichdensity and sound speed may be derived; theseare fundamental to ocean science andclimatology.Salinometers provide a reference to the widelyaccepted Practical Salinity Scale.

Standard MethodCTD & Water Samples AutoSAL

Limitations• Temperature stabilized environment• Sequential standardization• Skilled staff• SSW is expensive• Warming samples may change apparent salinity

The Future…now- High Performance- Easy to Use- Operates at in situtemperatures- Small size

Concepts of the Small Salinometer:1. Direct comparison of conductivity of sample andstandard2. Direct reading of R t over wide temperature range

Previous works(b) Ukraine – SevastopolInductive method(a) China – Tienjin. in Collaborationwith Tim Dauphinee, NSERC CanadaTwo conductive cells

Dual chamberInductive systemBased on standardRBR technology

Dual Chamber principleOil BathFluid outletsSample CellReference CellFluid inlets

Concepts of the Small Salinometer:1. Direct comparison of conductivity of sample and standard2. Direct reading of R t over wide temperature range

Salinometers measure R tPractical Salinity Scale - 1978

Test ResultsMS-310 Repeatability Using Samples of Constant Salinity2534.9022434.900T °C23TemperatureSalinity34.898Salinity psu2234.8962110:32:00 12:00:00 12:48:00 13:36:00 15:14:00 16:15:00time34.894

Test ResultsCalibration of Temperature SensorResiduals Versus TemperatureResiduals °C0.00100.00050.0000-0.0005-0.00100 5 10 15 20 25 30 35Temperature °C

Test ResultsR t variation with temperature for samples of Standard Seawater

Test ResultsMS-310 and AutoSal 8400B against OSIL Linearity pack (1 trial)

Salinometer Drift Comparison0.0035Figure 4. D298 Autosal and MS-310 standardization drift0.003dS=Sssw(end)-Sssw(start), PSS-780.00250.0020.00150.0010.00050-0.00051 2 3 4 6 8 12 16 19 22 25 27 30 32 35 39 42 45 47 50 53 56 60 63-0.001-0.0015Autosal driftStation numbersMS-310 drift

Performance data compared with PortaSal and AutoSalRangeAutoSal8400B0.0001 to1.15PortaSal8410A0.0001 to1.15MicroSalMS-3100.0001 to2.00 RtAccuracy 0.002 0.003 0.002 psuResolution 0.0002 0.0003 0.0002 PsuRoom Temp +0°; -2° +0°; -2° 15° to 30° CBath 16.8 9 2 LitresWeight 70 29 5 kgPower 400 200 10 wattsSupply Voltage 110/220 AC 110/220 AC 12 DC volts

Easy to useMS-310 User InterfaceWindows ® -basedcontrol panel streamlinesAnd simplifies operation

Small Size• 280mm x 280mm x 180mm•5kg• 12VDC

What else can I do with the MS-310?• Thermosalinograph• Measure other fluids (guacamole?)• Immerse in bath for direct calibration of CTDs• Autosamplers• Submersible ocean salinometer (ZEFICC)• Investigate behaviour of seawater types

Characterization of various seawater types over temperature rangeDec06-Jan07 Different waters vs IAPSO SSW Salinity-Temperature test residuals0.05000.04000.0300dS=Ssample-Sssw, PSS-780.02000.01000.00000 5 10 15 20 25 30-0.0100-0.0200SSW Pacific seawater Test bath Salt water PEI seawater-0.0300Temperature, deg.C

ConclusionsThe MS-310 represents the future of scientific salinity measurement, allowingmeasurement of salinity samples directly after CTD retrieval, outside the lab; thenearest thing to in situ salinometry.This offers a new perspective for understanding the nature of the conductivitymeasurements of seawater and opens doors beyond the PSS-78.Water samples should not have to be adjusted to a salinometer’s comfortconditions, rather the salinometer should adjust to the CTD measurementconditions – this is the future of salinity technology