www.ncof.gov.uk ostia : transition to an operational system john stark, craig donlon. globcolour /...

www.ncof.gov.uk

OSTIA : Transition to an Operational System

John Stark, Craig Donlon.GlobColour / Medspiration Workshop, 4-6 Dec. 2006

www.ncof.gov.uk

Overview

OSTIA : Operational Sea surface Temperature and sea Ice Analysis

• Description of the OSTIA system.– Data processing– Analysis & bias correction.– Products.

• From innovation to operation. – The transition process.– Operational status.

• Products and verification.

www.ncof.gov.uk

Operational SST & Sea Ice Analysis

• Daily 1/20° (~5.6km) global SST analysis using optimal interpolation.

• Blend of data sources, using satellite (microwave & IR) and in situ data.

• Now running daily in an operational suite starting at 0600 UTC.

• Persistence based; No explicit model.

• Uses sea ice analysis performed by EUMETSAT OSI-SAF (met.no / DMI).

Sample analysis for 24 Jan 2006

www.ncof.gov.uk

Daily SST

Basic Architecture

Quality Control-Background check -Diurnal warming flagging

Satellite Bias Estimation-Find match-ups -O.I. estimate.

O.I. Analysis-Using 2 background error scales-Spatially varying backgrd. errors

Data Sources

Anomaly Persistence Forecast

With relaxation to climatology

www.ncof.gov.uk

OSTIA : Source DataSensor (Platform)

Type Resolution Data Source Coverage Subsa-mpling

AMSR-E(Aqua)

Microwave ~25km(swath)

Remote Sensing Systems (ssmi.com). L2P Format.

Global(~1 million/day)

22

TMI (TRMM) Microwave ~25km(swath)

Remote Sensing Systems (ssmi.com). L2P Format.

Tropics(~0.5 million/day)

None

AATSR (EnviSAT)

Infra-red ~1km (swath) Medspiration RDAC, L2P Format

Global(~2 million/day)

33

AVHRR -LAC(NOAA 17 & 18)

Infra-red ~1/10°(Grid)

Medspiration RDAC, L2P Format (NAR) &NAVOCEANO-JPL

North Atlantic (grid)(~0.5 million/day)

33

AVHRR -GAC(NOAA 17 & 18)

Infra-red ~1km(Swath)

NAVOCEANO-JPL (~2 million/day) None

SEVIRI (MSG1) Infra-red 0.1° (Gridded) Medspiration RDAC, L2P Format

Atlantic sector(~2 million/day)

None

In-Situ Ships, drifting and moored buoys.

In-situ Met Office MetDB (GTS)

Global(~25,000 /day)

None

Sea Ice SSMI, Gridded 10km, Gridded.

OSI-SAF (Met.no) Global. None.

www.ncof.gov.uk

Bias correction : The Importance of AATSR

AMSR-E Observations for 14 Dec. ‘05

Reference observations (With AATSR) Reference observations (No AATSR)

www.ncof.gov.uk

Bias correction : The Importance of AATSR

Match ups (<25km)More match ups especially in data-sparse areas

Analysed AMSRE bias for 14 Dec.

Large impact from additional match ups

www.ncof.gov.uk

AATSR bias correction & SSES.

• AATSR bias specification has a significant impact on OSTIA. • A short reanalysis showed that the AATSR SSES bias was

too large. • We appreciate the rapid response of Medspiration in

changing the SSES bias (from 0.33 to 0.19).– But the change was not directly communicated to us…

Difference (K) between operational OSTIA and a run with AATSR bias=0.0

www.ncof.gov.uk

Products

• Browsable SSTs and Anomalies

http://ghrsst-pp.metoffice.com/data/private/sst_monitor/ http://lovejoy.nerc-essc.ac.uk:8080/ncWMS/godiva2.html

www.ncof.gov.uk

Products, Users and Applications

• Seasonal forecasting.– E.g. Winter forecast.

• Climate monitoring, inc. ENSO.• Aviation Forecasting Centre• Research

– E.g. High resolution SSTs for monsoon modelling (U. Reading)

• Intercomparison / validation– NASA Short-term Prediction Research and

Transition Centre (SPoRT)• Data supplied in GHRSST L4 format via

website :– http://ghrsst-pp.metoffice.com/pages/latest_an

alysis/ostia.html

– ftp details available on request.• NWP boundary condition.

– Beginning extensive trials with NWP suite.• Will participate in GHRSST GEO Action : DA-

06-03 to use ensemble techniques to improve SST uncertainty estimation.

NASA Sport Web Page.

www.ncof.gov.uk

Maintenance 1015 - 1215Z

Maintenance 1715 - 1815Z

opmarine opepsopnoncritopssfmmsopssfmoptempopmesop00:00

01:00

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QN00 0030 - 0050Z

QV00 0140 - 0210Z

QW000350 - 0425Z

QD00 0230 - 0305Z

QO000500 - 0600Z

QQ000615 - 0710Z

QL00 0735 - 0750Z

QE000930 - 0950Z

QD06 0830 - 0905Z

QW121550 - 1625Z

QD12 1430 - 1505Z

QD18 2030 - 2105Z

QU180030 -0115Z

QG000240 - 0350Z

QY000125 - 0230Z(from QG18)

QU000630 -0715Z

QG060840 - 0925Z

QY060725 - 0830Z(from QG00)

QU061225 -1315Z

QG121440 - 1550Z

QY121325 - 1430Z(from QG06)

QU121830 -1955Z

QG182040 - 2125Z

QY181925 - 2030Z(from QG12)

QA000310 - 0400Z(from QG18)

Q400 0240 - 0300Z

Q4030420 - 0520Z(from QY00)

Q406 0840- 0900Z

Q4090915 - 1015Z(from QY06)

QA06 1235 - 1310Z(from QG18)

QA121515 - 1605Z(from QG06)

Q412 1440 - 1500Z

Q4151615 - 1715Z(from QY12)

QA18 2110 - 2130Z(from QG06)

Q418 2040 - 2100Z

QJ18 2305 - 2350Z(from QG12)

Q4212150 - 2255Z(from QY18)

QM21 0120 - 0135Z(from QG18)

QM00 0215 - 0245Z(from QG18)

QC00 0650 - 0700Z(from QG18)

QM03 0720 - 0735Z(from QG00)

QM06 0815 - 0845Z(from QG00)

QC06 1225 - 1245Z(from QG18)

QM09 1320 - 1335Z(from QG06)

QM12 1415 - 1445Z(from QG06)

QC12 1905 - 1915Z(from QG06)

QM15 1930 - 1945Z(from QG12)

QM18 2015 - 2045Z(from QG12)

QC18 2305 - 2320Z(from QG06)

QH090010Z - 0030Z

QH120110 - 0310Z

QH180710 - 0850Z

QH210910 - 0930Z

QH001310 - 1540Z

QH031610 - 1700Z

QH061910 - 2120Z

EG000350 - 0650Z(from QG00)

EG121550 - 1850Z(from QG12)

EY060825 -1305Z(from EG00 &

QY06)

EY182025 -0105Z(from EG21 &

QY18)

Prelim Global SSFM0325 - 0330Z

Global SSFM0410 - 0430Z

NAE SSFM0240 - 0310Z

Middle East SSFM0345 - 0350Z

Falklands SSFM1235 - 1245Z


Middle East SSFM1550 - 1555Z

Global SSFM1610 - 1630Z



Falklands SSFM2310 - 2320Z




HALL1 (sx8) OPERATIONAL NWP SUITE SCHEDULE - 12 October 2006

Scott Irvine, 12 Oct 2006

Legend:Q4: UK 4km;T+3 & T+36QA: Southern AsiaT+9 & T+48QJ: AfricaT+48

Legend:QM: UK MesoscaleT+4 & T+48QC: FalklandsCAMMT+9 & T+48Q6: OSTIA SST

Legend:QH: Non Critical

Legend:QU: Global Update;T+9QG: GlobalT+48 & T+144QY: North Atlantic &EuropeanT+48

Legend:QD: NAE MarineSuiteQW: Global MarineSuiteQN & QV: FOAMQQ, QL & QE: Shelf-Seas Suite

QH150410 - 0430Z

fpss fpssfpfc fpfcfpfcfpfc fpfc

OPC

Fallback 0230

Fallback 0220

Fallback 0915

Fallback 0820

Fallback 2020

Fallback 2130

Fallback 1420

Fallback 1530

Fallback 0330

Fallback 0830

Fallback 1430

Fallback 2030

Legend:EG: GlobalEnsembleQY: NAEEnsemble

QZ180030 -0115Z

QZ000630 -0715Z

QZ061225 -1315Z

QZ121820 -1915Z

QJ06 1315 - 1335Z(recon from QG06)

QJ12 1820 - 1840Z(from QG12)

EY182025 -0105Z(from EG21 &

QY18)

Innovation to Operation…

• The transition to an operational system has many advantages

– Operators monitor the system 7 days a week.• Robust system.

– Machine resources are dedicated to the system (06000640 UTC).

– All procedures are clearly defined.– Allows rapid response to incidents.– Forces ‘Good Practise’, such as version control etc.

• But places requirements on the whole system:– All changes must be justified and documented.

• Any changes to data supply should be made a long time in advance if possible.

• Need stability in data delivery.– Not all operators have in-depth knowledge of the

system.• There should be simple ‘how-to’ procedures for likely

failure modes.– Processing MUST finish within the allocated time

period.

www.ncof.gov.uk

Sea Ice Reanalysis

• Currently performing a sea ice reanalysis for the SSMI era (1987-2005)– Hope to extend to SMMR (1979-1987).– Using processing system developed for the EUMETSAT

OSI-SAF.– Aim to quantify errors to provide a climate-quality

product.

Near 90 GHzNear 90 GHz

BootstrapBootstrap

NASA/TeamNASA/Team

Courtesy of Søren AndersenCourtesy of Søren Andersen

www.ncof.gov.uk

SST Reanalysis Plans

• SST Reanalysis back to 1981 using available satellite data and in situ obs.– Aim to produce a homogenous 25+ year SST data set for

seasonal forecasting by end of 2008. – Initially focus on Pathfinder (AVHRR) and (A)ATSR, by

end of 2007. – Intercomparison with other GHRSST (re-)analyses.– Requires access to (A)ATSR data for effective bias

correction.• Ideally L2P format.

– Open to collaboration• Error covariances, ensemble techniques, D.V. (ocean colour?),

aerosols (ocean colour)…

www.ncof.gov.uk

Priorities / Requests.

• Please maintain a continuous L2P data stream– Currently plan OSTIA to be the primary GMES Marine Core Services

L4 SST output. (Operational backup from France).– Recommend the L2P format as it facilitates the transition to new data

sources e.g. MetOp.

• Maintain AATSR Sentinel III– The presence of a high quality satellite SST data source is crucial to

our bias correction strategy.– Bias correction scheme will be compromised without AATSR.

• Ensure (A)ATSR is available (in L2P) for reanalysis efforts.• Please communicate changes to the system to users in an

operational manner (timely and accurate).

www.ncof.gov.uk

Conclusions

• We are treating Medspiration as an operational service– Using the service on a daily basis. – Have been some hiccups that should be ironed out .

• Short interruptions to the service have occurred.

• OSTIA’s strength is that is uses many complementary data sources.– Not totally reliant on a single data source – but accuracy

significantly enhanced by AATSR.

• Sea ice reanalysis will be available for use.

www.ncof.gov.uk ostia : transition to an operational system john stark, craig donlon. globcolour /...

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