11 March 2013 Tim Oakley, GCOS Implementation Manager

WIGOS TT Metadata

Global Climate Observing System

GCOS supports the “Global Framework for Climate Services”

Application Adaptation Mitigation

Climate Services Information System (CSIS)

UNFCCC

IPCC

User InterfacePlatform (UIP)

WCRP Research Modellingand Prediction (RMP)

WIGOS

GOOS GOS GAW GTOS

GCOS

GCOS comprises the climate relevant components of existiting observing systems.

GCOS ensures the sustained provision of reliable physical, chemical and biological observations and data records, across all domains, incl. hydrological and carbon cycles and the cryosphere.

Energy Energy

FoodFood

WaterWater

GCOS USERS

Observ

er

Scientist

Manager

Politician

Press

Sponso

rs

Secretariat

Different requirements for

Metadata

Focus on core

WMO

Motivation (1/2)

• Climate data are collected to allow for the best possible reconstruction of the state of the atmosphere / climate system across time and space and scales (basically from micro to global) in order to provide meteorological / climate information and services [including answers to questions like: How was the weather on 26 April 1986 when the Chernobyl reactor exploded? Why is the world temperature record in El Azizia (Libya) of 13 Sept. 1922 invalid?] .

• Therefore, observational Metadata should provide as much additional information as needed to optimally interpret observed meteorological / climate-related data in support to the above mentioned concept.

WMO

Motivation (2/2)

• In the context of assessing climate change and climate extremes, Metadata is crucial for attributing observed changes in the time series during the analysis. It allows to isolate artificial signals and shifts from the physical behaviour of the climate system . These artificial signals might be due to observation errors, the relocation of stations, changing observation procedures and technology, etc..

• Climate services requires information on the conditions in which data were recorded and processed (QC). Metadata is therefore also important for Climate Services (GFCS requirements)

WMO

Metadata requirements for climate

• Principles from a climate perspective: (i) Metadata should be managed in a way that allows for reflecting and retrieving all changes in the history of the observation/ instrument/ station/ network, such as siting, instrumentation, times of observations etc., but also establishment of station, commencement of observations, interruptions of operation, closure of station including one-to-one ID attribution (no use of same ID for different station through history); (ii) Metadata should allow for re-calculation of processed data.

• Metadata should be accessible and exchangeable equally conveniently as the meteorological/climatological data itself

WMO

Metadata requirements for climate (examples 1)• Station identifier(s) incl. index number and name

• Contact information (name, mailing address, Email address, phone numbers)

• Station actors (owner, manager, observers incl. their level of experience/qualification etc.)

• Station type (fixed land, fixed sea, mobile land etc.)

• Location (exact geographical location incl. elevation)

• Roughness, topography of station and environment, land use

• Photography, site plan and skyline diagram of station and environment

• Type(s) of soil incl. physical constants and profile of soil

• Type(s) of vegetation

• Observation programme (elements measured, reference time, times at which observations and measurements are made and reported, datum level to which atmospheric pressure data of the station refer)

• Inspection reports

WMO

Metadata requirements for climate (examples 2)

• Instruments (detailed instrument descriptions incl. manufacturer, model, serial number, date of installation )

• Instrument and instrument maintenance status (active, out of service, under repair; maint. frequency, calibration results etc.)

• Siting and exposure of instrument incl. photos

• Description of parameters measured by the instrument incl. unit, range, resolution, format, frequency, accuracy, method, algorithm, time constant, output averaging time etc.

• Principle of operation, method of measurement and observation, type of detection system, performance characteristics

• Data acquisition incl. sampling interval, averaging interval

• Correction procedures and calibration information

• Type of AWS incl. manufacturer, model, serial number

WMO

Metadata requirements for climate (examples 3)

• Measuring/observing programme of elements (times of observation, reporting frequency, data output

• Data processing method and intervalls

• Procedures, algorithms, calculation methods, constants, reported resolution

• Data handling: Quality Control procedures and algorithms incl. corrections by the observer

• Definition of QC-flags

• Storage procedures

• Method of transmission, data format, transmission time and frequency

• ? Station network Metadata, such as mission, operator, principles…??

Thank you for your attention