An Introduction to the Argo Data Sytem

South Pacific Workshop

11 – 14 October 2005

Mark Ignaszewski

FNMOC

South Pacific Workshop 11-14 October 2005

Outline

• Data system features

• Data system overview

• Available data

• Data access

South Pacific Workshop 11-14 October 2005

Argo: A global collaboration

• Participating countries: 20– Principle investigators: over 30

• National data centers: 9• Float manufacturers: 6

Goal of the data system• Provide a globally consistent data set• Freely and easily available• Meet the needs of the operational (real-time) and

research communities

South Pacific Workshop 11-14 October 2005

Data Consistency

• Data are distributed in controlled formats– GTS data are in the TESAC code form– Server data are in standardized netCDF files

• File format and data consistency are checked for every file before distribution

• Standardized quality control procedures are used by all data providers

• Meta-data for each float must be available before data for the float can be distributed

South Pacific Workshop 11-14 October 2005

Data Availability

• Data is distributed on the GTS for operational centers

• Two global data servers– One in France, the other in the US– Both servers offer open access to all data via

• FTP

• Web interfaces

South Pacific Workshop 11-14 October 2005

Communities Served

Operational (real-time) community• Standard automated QC checks detect and flag bad data• Data available on GTS and on the global servers• Data are distributed within 24 hours of observation

Research community• Standardized delayed-mode QC techniques have been

developed to calibrate Argo data (primarily salinity)– data are available 6 months to 1 year after observation

South Pacific Workshop 11-14 October 2005

Data System Schematic

UsersUsers

Global ArgoData Repository

ArgoInformation

Center

Data Assembly Centers

ArgoInformationGlobal

Data Assembly Centers

PrincipleInvestigators

Regional Data Assembly Centers

GTS

< 24 hrs

< 24 hrs

< 24 hrs

Within hours

6 months -1 year

> 1 year

AIC• Notify coastal states of floats that might enter their EEZ• Clearinghouse for Argo information

www.argo.net• Encourage participation by new countries• Provide international coordination

DACs• Receive data from floats• Apply standardized automated QC checks• Insert data on the GTS• Submit data to the GDACs• Within 24 hours of observation

• 9 DACs (currently)

• Archive raw data

RDACs• Build high-quality reference datasets for their regions from all available data

• for use in delayed-mode QC process• Perform basin-scale delayed-mode QC

• Produce regional products based on Argo dataPIs

• Retrieve data from DACs• Perform standardized delayed-mode QC• Send delayed-mode data to the DACs

GDACs• Validate data format and consistency• Provide ftp and Web access to ALL users

• 2 Global data centers (synchronized)

Official source of Argo data

GADR• Permanently archive Argo data• “Register” data with data inventories• Provide data on hardcopy media for distribution• Provide data transformation and integration tools• NODC

South Pacific Workshop 11-14 October 2005

Argo Data Coverage

1 – 30 September 2005:

         

5981 Argo observations2031 Active floats

South Pacific Workshop 11-14 October 2005

Combined Data Coverage

         

South Pacific Workshop 11-14 October 2005

Data: By Year

0

10000

20000

30000

40000

50000

60000

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

Year

Ob

se

rva

tio

ns

Delayed-mode

Real-time

Total Observations: 181,345Delayed-mode QC: 24,769

South Pacific Workshop 11-14 October 2005

Data Access: FTP

• US GDAC: ftp://usgodae1.fnmoc.navy.mil/pub/outgoing/argo

• French GDAC: ftp://ftp.ifremer.fr/ifremer/argo

• Index files: “Index” of all files on the GDAC – text files– Includes additional information for easy searching (positions, times, etc)

• 3 “views”– DAC view: float files as provided by the DACs (“dac” directory)

– Geographic view: files arranged by basin (Atlantic, Pacific, Indian) and day of observation (“geo” directory)

– Latest-data view: files arranged by day of receipt at the GDAC (“latest_data” directory)

South Pacific Workshop 11-14 October 2005

French GDACwww.coriolis.eu.org//cdc/argo.htm

South Pacific Workshop 11-14 October 2005

French GDACwww.coriolis.eu.org//cdc/argo.htm

South Pacific Workshop 11-14 October 2005

French GDAC: Data Selection Tool

South Pacific Workshop 11-14 October 2005

French GDACwww.coriolis.eu.org//cdc/argo.htm

South Pacific Workshop 11-14 October 2005

US GDAC: Web interfacewww.usgodae.org/argo/argo.html

South Pacific Workshop 11-14 October 2005

US GDAC: Argo Data Browser

         

www.usgodae.org/argo/argo.html

South Pacific Workshop 11-14 October 2005

US GDAC: Argo Data Browserwww.usgodae.org/argo/argo.html

South Pacific Workshop 11-14 October 2005

US GDAC: OPeNDAP

OPeNDAP Functionality• Export to binary or

ASCII• Subset• Subsample• Browse

www.usgodae.org/argo/argo.html

South Pacific Workshop 11-14 October 2005

US GDAC: LAS

• Select profile data by:• Time Period• Region• Depth Range

• Additionally constrain by• Float ID• DAC• Real-Time/Delayed

Mode• QC Values

www.usgodae.org/argo/argo.html

South Pacific Workshop 11-14 October 2005

US GDAC: LAS

LAS

Gaussian

Metadata

Pie

Waterfall

Comma Separated

HTML Text

South Pacific Workshop 11-14 October 2005

Important Addresses

• AIC Entry Page: www.argo.net

• Argo Project Office: www.argo.ucsd.edu• Argo Information Center: argo.jcommops.org

• French GDAC: www.coriolis.eu.org/cdc/argo.htm• US GDAC: www.usgodae.org/argo/argo.html

• Data Guide: www.coriolis.eu.org/cdc/argo/example/Argo_data_guide.pdf

Please Provide Feedback!

• Argo mailing list service: listes.cls.fr/wws/info/argo