An Introduction to the Argo Data Sytem

1
An Introduction to the Argo Data Sytem

• South Pacific Workshop
• 11 14 October 2005
• Mark Ignaszewski
• FNMOC

2
Outline

• Data system features
• Data system overview
• Available data
• Data access

3
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

4
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

5
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

6
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

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Data System Schematic
Users

• 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 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

Argo Information
Argo Information Center

• PIs
• 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

Global Argo Data Repository
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Argo Data Coverage
5981 Argo observations 2031 Active floats

• 1 30 September 2005

9
Combined Data Coverage
10
Data By Year

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

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Data Access FTP

• US GDAC ftp//usgodae1.fnmoc.navy.mil/pub/outgo
  ing/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)

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French GDAC

• www.coriolis.eu.org//cdc/argo.htm

13
French GDAC

• www.coriolis.eu.org//cdc/argo.htm

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French GDAC Data Selection Tool
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French GDAC

• www.coriolis.eu.org//cdc/argo.htm

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US GDAC Web interface

• www.usgodae.org/argo/argo.html

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US GDAC Argo Data Browser
www.usgodae.org/argo/argo.html
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US GDAC Argo Data Browser
www.usgodae.org/argo/argo.html
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US GDAC OPeNDAP
www.usgodae.org/argo/argo.html

• OPeNDAP Functionality
• Export to binary or ASCII
• Subset
• Subsample
• Browse

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US GDAC LAS
www.usgodae.org/argo/argo.html

• Select profile data by
• Time Period
• Region
• Depth Range
• Additionally constrain by
• Float ID
• DAC
• Real-Time/Delayed Mode
• QC Values

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US GDAC LAS

• LAS

Gaussian
Pie
Comma Separated
Metadata
HTML Text
Waterfall
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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/A
  rgo_data_guide.pdf
• Please Provide Feedback!
• Argo mailing list service listes.cls.fr/wws/info
  /argo