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Applying a metadata standard for

international weather information

Dr Steve Foreman, WMO and Met Office. 8 June 2005

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Introduction

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Contents

What is WMO?Why a metadata standard for WMO?IssuesWMO CoreConcepts and extensions

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WMO is….

UN Agency (1950)derived from IMO (1873)

Co-ordinate meteorologyweather

observations forecasts

climate changehydrologydisaster mitigation

187 Members

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WMO - Weather Forecasting

Rapid exchangeObservationsForecasts

Exchange formatsBrevity importantUnambiguous

language-independentcharacterbinary

“Obscure”

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WMO - climate

ObservationsModel simulations Interdisciplinary

meteorologyoceanographybiology

land marine

hydrologychemistry………..

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Why metadata?

Expanding science data not known data not exploited observations repeated

Exploitation decision systems non-experts

Need to: discover exchange

SMFW01 NWBB 270000AAXX 2700491753 32481 51008 10331 20259 40078 58017 83202 333 20263 59018 83816 84078=91754 01581 51812 10287 20245 40092 58017 60034 70182 85200 333 20256 59016 60017 85820=NNNN

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Issues for meteorology

MD_TopicCategoryCodeClimatology/Meteorology/Atmosphere

The whole of our discipline!

Subdivision would help

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Issues - time

ForecastsObservation time (span)Time forecast runValidity time of forecastAccumulation interval for, eg, rainfalletc

Climateuse 360 day year

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Issues - space

Irregular grids Different co-ordinatesECMWF store:

Spherical Harmonics (SH)

Gaussian Grid (GG) Latitude/Longitude (LL)

German weather model(http://www.dwd.de)

Coastal ocean model

http://oceanworld.tamu.edu/resources/ocng_textbook/chapter15/Images/Fig15-3.htm

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L R

Issues - space

Physical co-ordinatesOne parameter (eg “potential vorticity”) on a

constant value of another (eg “potential temperature”).

L

R

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Issues - continua

Feature or coverage – or both?Coverage obvious candidate, but

3 dimensional fields restrictive definition

Prefer Feature Catalogue flexible gridsone variable using other as co-ordinate

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Issues - implementation

Travelling metadatamany messages containing small packets of datanot practicable to send metadata with each oneprobably need to link to unchanging elements

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WMO Core

Subset of ISO 19115with extensions and interpretations

Testingclimate observations

http://cliware.meteo.ru/wdccatalog/index_en.htmlArctic studies

http://acsys.npolar.no/adis/adis.php#Datasetsautomated extraction from routine weather data

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Possible extensions

Community sub-topicsDefinitions of timeDefinitions of spaceReplace “coverage” with “features”