GCOS SST WG plansGCOS SST WG plans

Nick RaynerNick Rayner

OOPC-12, 2OOPC-12, 2ndnd May 2007 May 2007

Executive CommitteeExecutive Committee

• Tom Smith, NOAA (Co-chair)Tom Smith, NOAA (Co-chair)

• Nick Rayner, Met Office (Co-chair)Nick Rayner, Met Office (Co-chair)

• Ken Casey, NOAAKen Casey, NOAA

• Alexey Kaplan, LDEOAlexey Kaplan, LDEO

• Liz Kent, NOCSLiz Kent, NOCS

• Dick Reynolds, NOAADick Reynolds, NOAA

• Ed Harrison, PMELEd Harrison, PMEL

• Craig Donlon, Met OfficeCraig Donlon, Met Office

Outline Terms of ReferenceOutline Terms of Reference

• To record and evaluate the differences among To record and evaluate the differences among historical and near real time SST and SST/SI analyseshistorical and near real time SST and SST/SI analyses

• To identify the sources of differences in the analysesTo identify the sources of differences in the analyses• On the basis of comparison of those differences with On the basis of comparison of those differences with

the expected climate signals in the SST patterns, to the expected climate signals in the SST patterns, to recommend actions needed to ensure the quality and recommend actions needed to ensure the quality and consistency of the SST and SST/SI analysesconsistency of the SST and SST/SI analyses

• To establish criteria to be satisfied by SST and SST/SI To establish criteria to be satisfied by SST and SST/SI analyses to ensure the quality and consistency analyses to ensure the quality and consistency required by the Global Climate Observing System required by the Global Climate Observing System (GCOS)(GCOS)

• Liaise with all appropriate bodiesLiaise with all appropriate bodies• To report annually to AOPC and OOPC on progress To report annually to AOPC and OOPC on progress

and recommendationsand recommendations

Outline planOutline plan

• Agreed set of diagnosticsAgreed set of diagnostics

• Initial set of analyses and input dataInitial set of analyses and input data

• Host websiteHost website

• Data formats and inter-comparison toolsData formats and inter-comparison tools

• Communication plan Communication plan

• Turning the differences and similarities Turning the differences and similarities we discover into useful information for we discover into useful information for usersusers

Agreed set of diagnosticsAgreed set of diagnostics

• Initial phase:Initial phase:– Time series of global and hemispheric anomalies Time series of global and hemispheric anomalies – Time-latitude sections of anomaliesTime-latitude sections of anomalies– Fields of standard deviation, linear trend and Fields of standard deviation, linear trend and

lag1 correlation lag1 correlation • Follow on phase:Follow on phase:

– Maps of RMS differences between fieldsMaps of RMS differences between fields– Time averaged difference mapsTime averaged difference maps– Time series for selected regions and a small Time series for selected regions and a small

selection of GHRSST diagnostic data set sitesselection of GHRSST diagnostic data set sites– Spatial autocorrelations.Spatial autocorrelations.

Initial set of analysesInitial set of analyses

• Kaplan et alKaplan et al

• HadISST1HadISST1

• NOCS SST analysisNOCS SST analysis

• ERSSTERSST

• AVHRR PathfinderAVHRR Pathfinder

• OIv2OIv2

• Daily OI SSTDaily OI SST

• OSTIAOSTIA

Plus input data, including ICOADS and HadSST2

Host websiteHost website

• GHRSST-PP Reanalysis Long Term GHRSST-PP Reanalysis Long Term Stewardship and Reanalysis Facility: Stewardship and Reanalysis Facility: http://ghrsst.nodc.noaa.gov/http://ghrsst.nodc.noaa.gov/

Data formats and inter-Data formats and inter-comparison toolscomparison tools

• NetCDF-3 allows use of pre-existing NetCDF-3 allows use of pre-existing data comparison tools, such as Ferretdata comparison tools, such as Ferret

• Compatible with GHRSST-PP fieldsCompatible with GHRSST-PP fields

• Matlab and ASCII formats will also be Matlab and ASCII formats will also be maintainedmaintained

Communication planCommunication plan

• Draft and agree a document based on this Draft and agree a document based on this presentation and feedback [June 2007]presentation and feedback [June 2007]

• Create an email contact list of other Create an email contact list of other international SST analysis colleaguesinternational SST analysis colleagues

• Send document with invitation to participate Send document with invitation to participate [end of August 2007][end of August 2007]

• Once we have initial results, widen the net Once we have initial results, widen the net and publicise to other users at appropriate and publicise to other users at appropriate meetingmeeting

• Explore possibility of a short paper or report.Explore possibility of a short paper or report.

Creating useful information for Creating useful information for usersusers

• Spread of different analyses gives initial Spread of different analyses gives initial indication of structural uncertainty indication of structural uncertainty

• Later propose to Later propose to – Explore differences in input data and QC Explore differences in input data and QC

techniquestechniques– Apply different analysis techniques to the same Apply different analysis techniques to the same

datadata

• Need to carry out a user requirements Need to carry out a user requirements exercise to find out what our users are exercise to find out what our users are trying to do and so what they need from us.trying to do and so what they need from us.

Liaison with appropriate Liaison with appropriate bodiesbodies

• GHRSST-PPGHRSST-PP

• WCRP WGNE/WGSF SURFA project on WCRP WGNE/WGSF SURFA project on common SST issuescommon SST issues

Meeting of the SST/SI WGMeeting of the SST/SI WG

• Currently discussing dates for Currently discussing dates for meeting of the whole WG to discuss meeting of the whole WG to discuss progress and points of common progress and points of common interestinterest– Fall AGU?Fall AGU?