meteoswiss acceptance procedure for automatic weather stations (awscheck)

Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

MeteoSwiss acceptance procedure for automatic weather stations (AWSCheck)J. Fisler, M. Kube, E. Grüter and B. Calpini

2 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheckJoël Fisler

Overview

• Introduction• Goals• Motivation• Methods• Results• Summary• Outlook


Introduction

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1976 1973

• Siting classifications change over time (usually to the worse)

• Quality of data can decrease over time• More factors than siting classification influence data quality:

• High quality instruments• Regular calibration of instruments• Proper maintenance

Periodic monitoring of weather stations and factors influencing data quality is crucial!


Goal

MeteoSwiss wants to develop a procedure that is able to determine the quality of

measurement data based on an assessment of the corresponding automatic weather

station.

The result should be simple and easy to understand (e.g. good, acceptable, bad).


• MeteoSwiss includes data of partner stations (both public and private sector): Is their data reliable?

• Create a quality label for MeteoSwiss’ own stations• Higher credibility of extreme values• Increase awareness for measurement data quality• Responsibility as national weather service to follow

WMO recommendations (CIMO guide)• Collect metadata about weather stations

Motivation


Methods

Cycle repeated every 5 years!

Operator = Meteorological service, e.g. MeteoSwiss or private companyAuditor = Neutral third-party organization conducting assessment


Step 1: Pre-Analysis

When? Some weeks or months before audit on site Who? Auditor What? Based on documents provided by operator:

• Does AWS meet requirements to be certified?• What instruments are installed?• How is maintenance done?• History documentation?• …


Step 2: Audit on site

When? One day visit every five years Who? Auditor and operator together What? For each instrument auditor and operator fill

out questionnaire at the location of the AWS. As a result, AWSCheck gives a first assessment for the installed instruments using the categories green, yellow and red


Step 2: Audit on site - Questionnaire


Step 3: Post-Analysis

When? After one year (then: yearly reports) Who? Operator What? Statistics on performance of instrument:

• Measurement and transmission interval 10min?• Downtime of an instrument below 3 days?• Data availability above 96%?• Data delivery time?• …


Methods: The challenge of mountainous terrain in Switzerland

In mountainous terrain it is not possible to strictly follow CIMO recommendations:

•Measurement height: Due to high snow level instruments are installed above 2m. To respect this AWSCheck allows measurement heights of up to 3m for mountain stations.

•Topography: The Leroy siting classification defines a flat terrain without any obstacles. In mountain regions or in steep valleys some of the Leroy criteria cannot be met. Therefore AWSCheck allows higher Leroy classes at sites considered as “special topography”.More adaptations for Switzerland are listed in the paper!It’s a Swiss procedure adaptable for other countries!


Results of acceptance procedure

Fully compliant All WMO/CIMO requirements fulfilled

Fully compliant All WMO/CIMO requirements fulfilled

CompliantMost requirements fulfilled

CompliantMost requirements fulfilled

Not compliantSome important WMO requirements not fulfilled! Be aware of the

limitations and use data with caution.

Not compliantSome important WMO requirements not fulfilled! Be aware of the

limitations and use data with caution.

Each instrument is rated using the following categories:

ClimatologyClimatology MeteorologyMeteorology WarningsWarnings




Results: Site classification examples

Fully CompliantCompliantNot Compliant

Not Compliant


Summary

• Procedure to determine measurement data quality based on an assessment of weather station.

• Three steps: pre-analysis, audit on site, post-analysis.• Labels instruments as fully compliant, compliant and

not compliant.• Applied every five years to ensure that label is still valid.• Audits carried out by a neutral third party organization


Outlook

Implementation of step 3 (post-analysis) into the MeteoSwiss data warehouse.

Assessment by METAS (national agency of the International Bureau of Weights and Measures) of 40 MeteoSwiss and partner stations in 2013

Based on the results of the assessments AWSCheck will be further optimized

Development of App for smartphones and tablets


References (excerpt)

• DWD (2001). Richtlinien für automatische Klimastationen. Offenbach, Deutscher Wetterdienst.

• KUBE, Marlen, STOCKER, Catherine (2012). Qualitätssicherung von Messstationen. Fachkonzept SMN3, Version 0.6.

• WMO (2010a). WMO Guide to Meteorological Instruments and Methods of Observation. Geneva, World Meteorological Organization. WMO-No. 8 (2008 edition, Updated in 2010).

• WMO (2010b). Commission for Instruments and Methods of Observation – Report of the Fifteenth session. Helsinki 2-8 September 2010. WMO-No. 1064.

Furthermore many scientists, climatologists, meteorologists, hydrologists, database experts, technicians and maintenance staff members have been consulted.


Contact

Federal Office of Meteorology and Climatology MeteoSwiss

Joël Fisler

Krähbühlstrasse 58

CH-8044 Zürich

Tel. +41 44 256 94 33, Mobile +41 79 875 32 37

[email protected]

http://www.meteoswiss.admin.ch


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meteoswiss acceptance procedure for automatic weather stations (awscheck)

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