Ice Tethered Profiler (ITP)Moorings

Ice Tethered Profiler (ITP)Moorings

WHOI Principle Investigators

John Toole

Rick Krishfield

Andrey Proshutinsky

WHOI Principle Investigators

John Toole

Rick Krishfield

Andrey Proshutinsky

Goal: Document/understand interannual change through sustained observations of the

Arctic ice pack, the overlying atmosphere, and the upper ocean water properties

Ice-Based ObservatoriesIce-Based Observatories

System SpecificationsSystem Specifications

• Capable of returning in real time, high accuracy daily (or semi daily) temperature and salinity profiles to 750m depth for 2 years.

• Deployable from light aircraft and/or helicopters through a conventional 10.5” (.26 m) ice-augured hole.

• Modestly priced, allowing them to be deployed in large numbers and be considered expendable.

• Capable of supporting plug-in modules for additional surface and/or subsurface instrumentation.

• Capable of returning in real time, high accuracy daily (or semi daily) temperature and salinity profiles to 750m depth for 2 years.

• Deployable from light aircraft and/or helicopters through a conventional 10.5” (.26 m) ice-augured hole.

• Modestly priced, allowing them to be deployed in large numbers and be considered expendable.

• Capable of supporting plug-in modules for additional surface and/or subsurface instrumentation.

Ice-Tethered Profiler SchematicIce-Tethered Profiler Schematic

Profiling Interval: 10m - 800 m or less

Profiling range: 1,500,000 m

Duration: 2.5- 3 years at one profile / day

Temperature specification: -35° C

Data telemetry: up to 50 kbytes / day

Sensors: Seabird 41-CP CTD (same as ARGO floats)

Telemetry: Seabird inductive link from profiler to surface unit;

Iridium link to shore

Power: lithium “DD” battery packs

Size: Profiler fits through an 10.5” holein the ice

Profile speed: .2 meters/sec. (2 hours RT)

ITP Sensor Payload OptionsITP Sensor Payload Options

• CTD

• DO – Dissolved Oxygen

• MAVS – Modular Acoustic Velocity Sensor

• Biohead – PAR Sensor, Fluorometer

• CTD

• DO – Dissolved Oxygen

• MAVS – Modular Acoustic Velocity Sensor

• Biohead – PAR Sensor, Fluorometer

Clamp on Inductive InstrumentsClamp on Inductive Instruments

• SAMI - PH

• SAMI (CO2) – CTD and PAR

• Microcat

• SAMI - PH

• SAMI (CO2) – CTD and PAR

• Microcat

ITPDeployment Operations

ITPDeployment Operations

Finding an Ice FloeFinding an Ice Floe

• Multi year preferred 1.5 – 4.5 meters thick.

• Medium height ice ridges surrounding the site for protection

• Few cracks.

• If a suitable ice floe can’t be located, ITP system can be deployed in open water.

• Multi year preferred 1.5 – 4.5 meters thick.

• Medium height ice ridges surrounding the site for protection

• Few cracks.

• If a suitable ice floe can’t be located, ITP system can be deployed in open water.

Ice Thickness SurveyIce Thickness Survey

Set up on an ice floehelo assist

Set up on an ice floehelo assist

Staging EquipmentStaging Equipment

Set up deployment tripodSet up deployment tripod

Drill ice holeDrill ice hole

Ice holeIce hole

Mooring anchorMooring anchor

Start deployment with wire weightStart deployment with wire weight

Wire payoutWire payout

ITP installed on mooring wire

ITP installed on mooring wire

Final Assembly of ITP electronics and mooringFinal Assembly of ITP electronics and mooring

Electro / Mechanical Inductive Hose Assembly

Electro / Mechanical Inductive Hose Assembly

Success!Success!

Can an ITP be Recovered?Can an ITP be Recovered?

Preferred Method - Smash it out! Preferred Method - Smash it out!

Recovery of ITP 42Recovery of ITP 42

ITP 36 Deployed 08/29/2009 at 79 12.7N, 125 42.3E on NABOS cruise. Found in Iceland 2/2012

ITP 36 Deployed 08/29/2009 at 79 12.7N, 125 42.3E on NABOS cruise. Found in Iceland 2/2012

Data ExamplesData Examples

Double-diffusive Staircase StratificationDouble-diffusive Staircase Stratification

Expanded views of the potential temperature profiles and potential temperature - salinity diagrams. Above the Atlantic Layer, temperature and

salinity both decrease with height: a stratification subject to the diffusive layering form of double diffusion that is manifested by the staircase profile

resolved by the ITP (left). Over plotted potential temperature-salinity curves at the level of the Atlantic Layer (right) clearly document intrusions that erode

this warm salty water mass.

ITP1 Atlantic eddy profile ITP1 Atlantic eddy profile

Expanded view of Atlantic water eddyExpanded view of Atlantic water eddy

ITP3 engineering dataITP3 engineering data

The End Thank You