SOCATSurface Ocean CO2 ATlas

Are Olsen1, Benjamin Pfeil1, Dorothee Bakker2, Maria Hood3, Nicolas Metzl4, Christopher Sabine5, Alex Kozyr6

WWW.BJERKNES.UIB.NO

1Bjerknes Centre & UGOT, 2Univ. East Anglia, 3IOCCP, 4LOCEAN, 5PMEL, 6CDIAC

SOCAT GOAL

Prepare a open accessible uniform format and quality controlled global surface ocean CO2 data base

Two products:

1.A 2nd level quality controlled global surface ocean fCO2 data set

2.a gridded SOCAT product of monthly surface water fCO2 means, on a 1ox1o grid with no temporal or spatial interpolation – i.e. bin averages.

SOCAT History

SOLAS

CARBOOCEAN

SOCOVV

Pfeil and Olsen continues

SOLAS/IMBER CARBON group meeting at ICDC73 WGs appointed,WG1: Metzl, “..organiseavaliability of present and future data in a single center.”

2005 2007

SOCAT

ORFIOS

2001

Bakker & Dittert starts putting all available pCO2 data together in a uniform format

SOCAT History

SOLAS

ORFIOS CARBOOCEAN

SOCOVV

2001

Bakker & Dittert starts putting all available pCO2 data together in a uniform format

Pfeil and Olsen continues

SOLAS/IMBER CARBON group meeting at ICDC73 WGs appointed,WG1: Metzl, “..organiseavaliability of present and future data in a single center.”

2005 2007

SOCAT

We are here

SOCAT ORGANISATION

Global Focal PointBakker (Chair), Metzl, Olsen, Pfeil, Sabine

Regional Groups

PACIFICFeelyNojiri

ATLANTICSchusterLefevre

INDIANSarma

COASTALBorgesChen

SOUTHERNTilbrookMetzl

SOCAT ORGANISATION

Global Focal PointBakker (Chair), Metzl, Olsen, Pfeil, Sabine

Regional Groups

PACIFICFeelyNojiri

ATLANTICSchusterLefevre

INDIANSarma

COASTALBorgesChen

SOUTHERNTilbrookMetzl

Whip-inHood

SOCAT ORGANISATION

Global Focal PointBakker (Chair), Metzl, Olsen, Pfeil, Sabine

Regional Groups

PACIFICFeelyNojiri

ATLANTICSchusterLefevre

INDIANSarma

COASTALBorgesChen

SOUTHERNTilbrookMetzl

Whip-inHood

Live Access ServerHankin,Malczyk

SOCAT contains all publically available data + data contributed under the explicit condition that they will not be released untill September 2009 – Jena ICDC 8 conference

Data have been downloaded from webpages, e.g. CDIAC and submitted after request

44% US and Canada36% Europe18% Japan1.5% Australia

Most PIs have been very willing to share their data, this is very appreciated. Rik W largest contributor, 450 cruises, 21.5%.

SOCAT DATA

Growth of SOCAT

SOCAT contains almost 10e6 data points, almost 7e6 with surface CO2, divided over 2000 cruises.

Agree on Sept 2009 embargo+ Maria request PIs to submit data

Growth of SOCAT

Status April 2007

Growth of SOCAT

Status June 2008

Growth of SOCAT

Status Sept 2008

0

50.000100.000

200.000

150.000

300.000

Count

Spatial Distribution

Temporal Distribution1968-2008

SOFAR in SOCAT• We have learnt how to work with 2000 cruise data files

• File formats have been uniformed

• EXPOCODES have been assigned (ship code + sailing date)

• Metadata have been collected and organised

• ETOPO2 bottom depths, NCEP/NCAR atm. pressures and WOA salinities have been added to each data point

• fCO2 has been computed/recomputed from 13 different reported surface CO2 parameters using a single set of

equations

• Fully transparent process, every step can be checked, no data have been lost

To Come in SOCAT

Data will be reviewed and QC’d by regional groupsEach cruise will be assigned a “Wanninkhof Flag”, WF

(A) A good cruise-followed approved methods/SoP criteria-metadata documentation complete-2ndary QC preformed and deemed acceptable

(B) An acceptable cruise-followed approved methods/SoP criteria-metadata documentation complete-no 2ndary QC could be preformed because data were obtained in a region or time where no other data were available for comparison

(C) An acceptable cruise-did not follow approved methods/SoP criteria-metadata documentation complete-2ndary QC preformed and deemed acceptable

(D) Undocumented data-inadequate information about methods/procedures -metadata documentation incomplete

(F for failure) Failed QC checks (do not show in dataset)

(N) Not yet QC’d

SOCAT Quality Checks

Comparison of cruises: Comparison through MLRCrossover checks

Other:Compare atmospheric xCO2 data with GLOBALVIEWEvaluate key variables (T)Calculate ship speed- geographyEvaluate temperature normalised fCO2

USE Live Access Server (LAS) at PMEL for data access and QCTrace each change using SUBVERSION – Pfeil Friday

Reviewed at the SOCAT 2nd technical meeting, Paris June this year, report available at IOCCP home pages

Time Table

2007 Initiated at SOCOVV

2008 Follow up technical meeting

2009 September, present at ICDC 8 Jena

Jan 2009, Coastal Group meets in Kiel

March 2009, Pacific/Indian/Southern Ocean groups meets in Tsukuba

May/June 2009, Atlantic group meeting

SUMMARY

• SOCAT appears to become a VERY comprehensive surface ocean fCO2 database

• It is also a very comprehensive surface T&S database

• People have been very generous with their data

• Contains almost 7e6 surface ocean fCO2 observations

• The data will be expert reviewed and each cruise will carry a quality flag

• All steps are transparent and traceable

• 1st version planned release, Sept. 2009. Plans are to regularly update SOCAT in the future, how to practically organise this is not yet entirely clear.