Argo a year ago.

• 500 floats.• Regional coverage only.

Argo today.

• 1043 floats.• Rapid data availability on GTS and WWW.• Coverage approaching global, but major gaps.

Argo a year from now.

• 1700 floats?• Scientific quality data stream.• Global coverage.

Draft deployment plans for the Pacific and Indian Oceans.

Argo data quality control elements

Data from floats

All good and questionable data

Delayed-mode (DM) data streamFunction: Provide secondary QC. Produce“best guess” range of adjustments if possibleby inspecting series of profiles (hence DM).Provide feedback to RT system.Users: All needing adjusted data with error ests.Timeframe: 6-12 months after transmission.Who/Where: Perform by PIs with DM Centres.

Regional AnalysisFunction: Provide basin-wide synthesis of all float data,float-float intercomparison, reanalysis, etc., so as toproduce datasets adequate to study decadal change.Timeframe: Lifespan of float.Who/Where: Perform by Regional Centres.

Real-time (RT) data streamFunction: Provide primary QC to raw float data.Assign quality flags. No adjustments.Users: Operational centres, data assimilation,researchers needing timely data.Timeframe: 24-48 hrs after transmission.Who/Where: Perform by National Data Centres.

FUTURE

* All data can be obtained from the two Argo Global Data Assembly Centres: Coriolis at IFREMER, and USGODAE at Monterey.

Inspect output

Argo delayed-mode salinity QC

Good + questionable data from RT stream

Climatological ests. from WJO

Float and climatologyagree. No adjustment

needed

Parameter adjustmentfine tuning etc.

PI/expert evaluation ofdivergence. Due to float or toinadequate climatology? Use

oceanographic knowledgeand supplementary float/

CTD info to decide.

Float data and climatology diverge

Climatology deficient. Float good within salinity spec.

No adjustment needed

Climatology good. Suspect sensor drift. Correct by WJOor other method. Issue best-

guess adjustment range. Record calibration details

Unclear whether divergenceDue to climatology or sensor.

Cannot correct. May needlater reanalysis at regional

centre.

Good QC’d dataWith changed calibration

Indian Argo Project1. Deployment of 150 floats

(NIOT)2. National Data Center

• Data Reception• Processing and Real time QC

3. Data Dissemination through GTS and Internet

4. Publish Products on WEB5. Data Analysis 6. Data Assimilation (CAOS)7. Indigenisation of Floats

(NIOT)8. Capacity Building

Indian Argo Project1. Deployment of 150 floats

(NIOT)2. National Data Center

• Data Reception• Processing and Real time QC

3. Data Dissemination through GTS and Internet

4. Publish Products on WEB5. Data Analysis 6. Data Assimilation (CAOS)7. Indigenisation of Floats

(NIOT)8. Capacity Building

International Argo1. Regional Co-ordination

(Indian Ocean)2. Regional Data Center

Development of North Indian Ocean Hydrology

Delayed mode QC

International Argo1. Regional Co-ordination

(Indian Ocean)2. Regional Data Center

Development of North Indian Ocean Hydrology

Delayed mode QC

Real-time Data Acquisition by INCOIS by 2004

The future of Argo:

What will the next generation of Argo look like?

How and when will Argo become “operational”?

Floats are complex devices that have great potential for revolutionizing our understanding of ocean circulation. This complexity will require the attention of the research community for many years to come.

New sensors:

• Optical sensors (fluorometers; backscatter; etc.) See Bishop et al. (Nature, 2002) for an example.

• Dissolved oxygen (at least 2 types)

• Acoustic sensors (wind, rainfall, etc.)

• Biological sensors (nutrients, etc)

• ?????

The main limitations to adding new sensors are weight and power requirements. Floats provide an excellent platform for measuring many variables.

ARGO and biogeochemical observing systems

New sensors: dissolved oxygen

In a SBE/UW collaboration, a dissolved oxygen sensor for use on profiling floats has been developed and tested. The sensor is a Clark polarographic-type sensor similar to the present generation of SBE oxygen sensors on shipboard systems.

Acoustic sensors on profiling floats:

Dr. Jeffrey Nystuen’s group at the UW Applied Physics Laboratory has designed and constructed an Acoustic Rain Gauge suitable for use on profilng floats.

First deployment: Eastern N. Pacific, along the N. American coast, from the TG Thompson in November 2003.

FLOAT ENDCAP AND CTD WITH BROADBAND HYDROPHONE

The acoustic rain gauge:

Rainfall and wind speed can be measured acoustically using the spectrum of ambient acoustic noise in the ocean. The results at right are from a TAO mooring in the equatorial Pacific (Nystuen, 1999).

At moderate wind speeds there is good agreement between wind measured from an anemometer and winds inferred acoustically.

[a float can make similar measurements while submerged]