1. Federal Department of Home Affairs FDHA Federal Office of Meteorology and Climatology MeteoSwiss MeteoSwiss acceptance procedure for automatic weather stations (AWSCheck) J. Fisler, M. Kube, E. Grüter and B. Calpini

2. 2 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler Overview Introduction Goals Motivation Methods Results Summary Outlook

3. 3 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler Introduction 1997 1985 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!

4. 4 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler 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).

5. 5 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler 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

6. 6 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler Methods Pre-Analysis (Auditor) Audit on site (Auditor & Operator) Post-Analysis (Operator) Cycle repeated every 5 years! Operator = Meteorological service, e.g. MeteoSwiss or private company Auditor = Neutral third-party organization conducting assessment

7. 7 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler 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? … Pre- Analysis Audit on site Post- Analysis

8. 8 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler 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 Pre- Analysis Audit on site Post- Analysis

9. 9 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler Step 2: Audit on site - Questionnaire

10. 10 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler 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? … Pre- Analysis Audit on site Post- Analysis

11. 11 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler 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!

12. 12 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler Results of acceptance procedure Fully compliant All WMO/CIMO requirements fulfilled Fully compliant All WMO/CIMO requirements fulfilled Compliant Most requirements fulfilled Compliant Most requirements fulfilled Not compliant Some important WMO requirements not fulfilled! Be aware of the limitations and use data with caution. Not compliant Some important WMO requirements not fulfilled! Be aware of the limitations and use data with caution. Each instrument is rated using the following categories: Climatology Meteorology Warnings Climatology Meteorology Warnings Climatology Meteorology Warnings

13. 13 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler Results: Site classification examples Fully Compliant Compliant Not Compliant

14. 14 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler 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

15. 15 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler 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

16. 16 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler References (excerpt) DWD (2001). Richtlinien für automatische Klimastationen. Offenbach, Deutscher Wetterdienst. K UBE, Marlen, S TOCKER, 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.

17. 17 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler 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 joel.fisler@meteoswiss.ch http://www.meteoswiss.admin.ch

18. 18 MeteoSwiss acceptance procedure for automatic weather stations | AWSCheck Joël Fisler Questions