4.1 alisonmclaren metoffice products

8/10/2019 4.1 AlisonMcLaren Metoffice Products

1/23

MyOcean2 User Training Workshop, Met Office, Exeter, 2-4 July 2014

Met Office contribution to

MyOcean2

Dr. Alison McLaren, Ocean Forecasting R&D, Met Office


2/23

Contents

Met Office systems that generate MyOcean 2

products:

North West Shelf (NWS) analysis & forecast

Global analysis and coupled forecast

Sea surface temperature (SST) analysis

Operational robustness

Product dissemination / Product quality control

Research & development

Summary


3/23

North West Shelf products

NWS or 004

Met Office lead the NWS Monitoring and

Forecasting Centre for MyOcean2


4/23

NORTHWESTSHELF-ANALYSIS-

FORECAST-PHYS-004-001

Forecast Ocean Assimilation Model(FOAM)

NWS configuration = 7km resolution

Runs every day producing analysis of previous day plus 5 daysforecast (target availability time = 09:00 UTC)

NEMO physical model:

Nucleus for European Modelling of theOcean

Managed/developed by Europeanconsortium

Physical NWS configuration developedby NOC and Met Office

Temperature, salinity, currents and sea-level

Tides Terrain following vertical coordinates

Assimilate in-situ and satellite SSTobservations (~40,000 a day but very

variable)


5/23

1/4 Global FOAM

1/12 North Atlantic

Forcing NWS system

Atmospheric forcing from Met Office globalweather prediction system

Lateralboundaries

Rivers currently from climatological dataset,future upgrade to use near real-time E-HYPEmodel output

Baltic boundarycurrently treated

as river withclimatologicaldata, futureupgrade to useBAL model output


6/23


FORECAST-BIO-004-002

FOAM NWS

configuration includes

ERSEM Ecosystem model

Developed by PlymouthMarine Laboratory (PML)

Nutrients, phytoplankton,

zooplankton, bacteria,

chlorophyll, sedimentsPrimary production


7/23

NWS products

1 day analysis (previous day) & 5 day forecast


FORECAST-BIO-004-002

Daily mean, 24 vertical levels:

light attenuation

chlorophyll-a

dissolved oxygen

dissolved organic phosphate

dissolved organic nitrate

total phytoplankton biomass

net primary productivity


FORECAST-PHYS-004-001

Daily mean and hourly

instantaneous, 24 vertical levels:

temperature

salinity

horizontal velocity

Hourly instantaneous, 3 levels(surface, mid-water, bottom)

as above

sea surface height


8/23

NORTHWESTSHELF_REANALYSIS_

PHYS_004_009

Daily mean and monthly mean, 24 vertical levels: temperature

salinity

horizontal velocity

NWS reanalysis using FOAM - upgraded systemrelative to current operational system; work to upgrade

operational system is currently on-going

1985-2012

Physical model onlyAssimilation of in-situ & satellite SST with NEMOVAR

Different forcing to operational system e.g. ERA-interim

atmospheric forcing


9/23

Global analysis and coupled forecast products

at 1/4resolution (GLO or 001)


10/23

Run daily producing 2 day analysis and 7 day forecast (target availability time =12:00 UTC)

48-hour observation window allows inclusion of much more data into the

FOAM system

Met Office Global system overview

T+0 T+168T-24T-48

Obs QC &processing GloSea5 forecast

3 hourly couplingto 50km

atmosphere

FOAM FOAM

Near-real-time data includingArgo, altimeter SSH, SSTand sea-ice concentration

Productdissemination


11/23

GLOBAL-ANALYSIS-FORECAST-PHYS-

001-015

Forecast: GloSea5 coupled seasonal prediction

system

NEMO/CICE at 1/4 coupled to Met Office atmosphere model

(50km)

Analysis: FOAM global configuration (1/4)NEMO ocean model

CICE sea-ice model

Met Office weather prediction system surface fields/fluxes

Assimilation of data using NEMOVART, S profiles (e.g. Argo) (~1,300 profiles a day)

Surface height (3 satellite altimeters)

Sea surface temperature (satellite and in-situ,

~500,000 obs a day)

Sea ice concentration (satellite)


12/23

Sea Surface Height field with surface drifter locations: KuroshioCurrent

GLOBAL-ANALYSIS-FORECAST-PHYS-001-015


13/23

GLOBAL-ANALYSIS-FORECAST-PHYS-

001-015

2 day analysis (previous 2 days) & 7 day forecast

Daily mean on regular lat-lon 1/4, 75 vertical levels:

Temperature

Salinity

Sea surface height

Horizontal velocity

Mixed layer depth

Sea ice fraction

Sea ice velocity

Sea ice thickness

SST l i d t


14/23

SST analysis products

SST or 010


15/23

SST-GLO-SST-L4-NRT-

OBSERVATIONS-010-001

Operational Sea Surface Temperature and Ice Analysis(OSTIA)

Global, daily, 1/20 gridded (no-gaps) product

Near real time (NRT): system runs every day producing

analysis for previous day (target availability time = 08:00UTC)

Persistence based: no underlying ocean model

Uses in situ (e.g. drifting buoys, ships), infrared and

microwave satellite SST data

Quality control of SST obs and satellite obs bias correction

Uses satellite sea ice concentration data

Includes lake temperatures and lake ice


16/23

Examples of input data

NOAAAVHRR ~ 1 x 106

MetOP - AVHRR ~ 7 x 105

TRMM-TMI ~ 5 x 105

MSG-SEVIRI ~ 8 x 105

Using ~ 6 million satellite and in-situ SST observations every day in

SST analysis

Satellite data organised through

Group for High Resolution SST(GHRSST)

Plus satellite sea ice

concentration observations

SST GLO SST L4 NRT


17/23

SST-GLO-SST-L4-NRT-


Examples of uses/users:

Lower boundary condition for weather forecasting systems Constraining/validating SST and sea ice in short-range oceanforecasting systems

Oceanographic research

Producers of SST products

5 datasets: Daily high resolution (1/20) SST and sea ice product (plus estimate of

SST analysis error)

Daily low resolution (1/4) SST anomaly relative to Pathfinderclimatology (plus low resolution SST field)

Daily low resolution SST bias fields Monthly mean low resolution SST

Seasonal mean low resolution SST

SST GLO SST L4 REP


18/23

SST-GLO-SST-L4-REP-


OSTIA reprocessed product

Uses in-situ and reprocessed satellite data

19852007

Same as near real-time OSTIA system pre Jan 2013

4 datasets:

Daily high resolution SST and sea ice product (plus estimate of SST

analysis error)

Daily low resolution SST anomaly relative to Pathfinder climatology

(plus low res SST field)

Monthly mean low resolution SST and sea ice

Seasonal mean low resolution SST

Examples of uses/users:

Constraining/validating SST and sea-ice in long-term

reanalysis systems (e.g. seasonal/decadal forecasting)

As a tool for climate monitoring

SST GLO SST L4 NRT


19/23

SST-GLO-SST-L4-NRT-


Global Ocean Sea Surface Temperature Multi

Product Ensemble (GMPE)

1/4global, daily, gridded product

Ensemble median and standard deviation of ~10 SST analyses

produced by various international institutes (GHRSST)

Near real time: system runs every day producing ensemble product for

previous day (target availability time = 17:00 UTC)

Mainly used as a monitoring tool for analysis data producers to assess

the consistency between various SST analysis products

But median has been shown to be more accurate compared to near

surface Argo data than contributing analyses


20/23

Operational robustness

Systems run in Met Offices operational suite onsupercomputer

Computing split between 2 halls for resilience

Full operational support, inc. 24/7 operator cover, use

of resilient systems, on call arrangements for responseto problems by scientific staff

Development of operational suite done through

development of a parallel suite

Allows full testing prior to

going operational

1-3 parallel suites per year

Product dissemination /


21/23

Product dissemination /Product quality control

Met Office is a Dissemination Unit as well asProduction Unit

Products transferred from supercomputer to

dissemination server

Also disseminate global reanalyses

Output from our systems is monitored by scientists

using bespoke monitoring systems

Action taken if major problem spotted (rare!)


22/23

Research & development

Important component to MyOcean and our workR&D work done by various teams in Met Office together

with external collaborators

Trials of developments carried out by operational ocean

team and assessed

If trial is successful, developments implemented in

parallel suite

Near real time systems evolve with timeusers

informed through Notifications of change or newcatalogue release

Reanalyses re-run with updated systems at various

intervalsusers informed through new catalogue

release


23/23

Summary

Met Office produces (and disseminates) the followingMyOcean products:

NWS analysis and forecast (NRT and reanalysis)

Global analysis and coupled forecast at 1/4 (NRT)

SST analysis (NRT and reprocessing) SST analysis multi product ensemble (NRT)

(Also disseminates global reanalyses)

Resilient and fully supported operational systems, and

quality monitored by scientists Products improved through pull-through of R&D

4.1 alisonmclaren metoffice products

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