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Intercomparisons

INTERCOMPARISONS


Upcoming and Recent Instrument Intercomparisons

WMO 2021 Upper-Air Instrument Intercomparison Campaign (UAII2021)

Letter of Call for Participation (June 2020)
- English

Manufacturers interested to participate in the intercomparison are invited to provide the required information on their radiosonde systems, by 12 July 2020, using the online questionnaire available here: https://www.surveymonkey.com/r/WMO_UAII_2021 

Letter on Expression of Interest to Participate (Nov. 2019)
- English    French   Spanish    Russian    Arabic

Useful information:

Concept note for the intercomparison approved by CIMO 18 (2018): WMO-No. 1227 (Recommendation 10 (CIMO-17)).

Presentation to manufacturers held at the occasion of MTWE 2019, in Geneva

 

13th International and Regional Pyrheliometer Intercomparisons (IPC-XIII, RPCs)

5th Filter-Radiometer Comparison (FRC-V)

3rd International Pyrgeometer Comparison (IPgC-III)

Davos, Switzerland, 28 September - 16 October 2020   --  POSTPONED TO 2021

Letter announcing postponement of IPC-XIII (July 2020)
- English    French   Spanish    Russian    Arabic

Letter of Announcement (April 2020)
- English    French   Spanish    Russian    Arabic

  • Annex I - List of WMO Regional Radiaton Centres (RRCc)
  • Annex II - Questionnaire - Request for financial support for participation at IPC-XIII and the RPCs

Online Registration at PMOD/WRC:  https://www.pmodwrc.ch/

 

12th International and Regional Pyrheliometer Intercomparisons (IPC-XII, RPCs)

4th Filter-Radiometer Comparison (FRC-IV)

2nd International Pyrgeometer Comparison (IPgC-II)

Davos, Switzerland, 28 September - 16 October 2015

Letter of Announcement (April 2015)
- English    French   Spanish    Russian    Arabic

Online Registration at PMOD/WRC: http://projects.pmodwrc.ch/ipc-xii

Short Film on IPC-XII (12 min, 5 min) What's NEW

RQQI - Radar Quality Control and Quantitative Precipitation Intercomparison

WMO Letter PR-6602 (15 November 2011) - Expression of interest to participate in RQQI

English    French   Spanish    Russian    Arabic

Annex I - Questionnaire: WMO/CIMO Radar Quality Control and Quantitative
Precipitation Estimation Intercomparison (RQQI)  [Word]  [pdf]

Annex II - Data Protocols for RQQI   [Word]  [pdf]

=== Reference material:
Report of IOC-RQQI meeting (Exeter, UK, 14-15 April 2011)


SPICE - Solid Precipitation Intercomparison Experiment

SPICE DATA PROTOCOL

Other SPICE Documents and Informations

WMO Letter PR-6686 (8 February 2013) - Third call for potential participants in SPICE

English    French   Spanish    Russian    Arabic


Questionnaires for Potential Participants - Deadline for Reply: 15 March 2013

Questionnaire on Solid Precipitation Gauges

Questionnaire on Snow Depth Gauges Questionnaire on Potential Intercomparison Sites

WMO Letter PR-6627 (23 February 2012) - Second call for potential participants in SPICE

English    French   Spanish    Russian    Arabic


Questionnaires for Potential Participants - Deadline for Reply: 15 March 2012

Questionnaire on Solid Precipitation Gauges

Questionnaire on Snow Depth Gauges Questionnaire on Potential Intercomparison Sites

WMO Letter PR-6601 (2 November 2011) - Preliminary expression of interest to participate in SPICE

English    French   Spanish    Russian    Arabic

Annex - WMO Solid Precipitation Intercomparison Experiment (SPICE)
            Mission Statement and Objectives

            English    French   Spanish    Russian    Arabic

=== Reference material:
Report of Joint ET-II and IOC-SPICE meeting (Geneva, 5-7 October 2011)


11th International and Regional Pyrheliometer Intercomparisons (IPC-XI, RPCs)
Davos, Switzerland, 27 September - 15 October 2010

Letter of Announcement (9 March 2010)
- English    French   Spanish    Russian    Arabic


8th WMO Intercomparison of High Quality Radiosonde Systems
Yangjiang, China, 12 - 31 July 2010

Announcements and Planning

Report ET/IOC meeting
Yangjiang, China, Sept. 2009

Shipping Procedure

 Local Arrangements

FAQ

Form for declaration of radio-transmitting equipment
(deadline end of February 2010)

FINAL REPORT

 

WMO Combined Intercomparison of Thermometer Screens/Shields in Conjunction with Humidity Measuring Instruments. --Ghardaïa, Algeria, mid 2008– mid 2009

 Announcements and Planning

Letter of
Announcement

Questionnaire I to potential participants

Operational Aspects of the  Intercomparison

Planning

Selected Instruments

Questionnaire II to selected participants

 
 
 
 Progress Reports

Report of the Project Leader (in French only)

Progress Report- I
(March 2007)

 
 

 
FINAL REPORT

 

WMO Field Intercomparison of Rainfall Intensity Instruments
Vigna di Valle, Italy
mid 2007– mid 2008

 Announcements and Planning

Letter of
Announcement

Questionnaire I to potential participants

Operational Aspects of the  Intercomparison

Data Acquisition System

Selected Instruments

Questionnaire II to selected participants

 
 

Instruction on shipment of instruments 

Summary          Letter-1          Letter-2         Letter-3          Pro-Forma Invoice  

Further instruction to participants

Letter of the Project Leader         FAQ

Meeting of the Participants (21-22 May 2008)

 
 Progress Reports

Progress Report- I
(March 2007)

Annex II Report of Site Manager

Annex III Positions of Instruments

Annex IV Customs Procedures

Annex V Data Acquisition System

Annex VI Data Analysis

Annex VII QC/QA

 

10th International and Regional
Pyrheliometer Intercomparisons (IPC-X, RPCs)
Davos, Switzerland
26 September - 14 October 2005

 Announcements and Planning

Letter of
Announcement

Annex I
List of RRCs

Annex II
Questionnaire on intended participation

 
 
 
 Progress Reports

List of Participants

Final Report ADC

Final Report

         

 

WMO Laboratory Intercomparison of Rainfall Intensity Gauges
France / Italy / Netherlands 
15 September 2004 – 15 August 2005

 Announcements and Planning

Rules and 
Procedures

Guidelines for
Participants

Participating 
Instruments

Lab addresses and contacts

Procedures for 
data analysis

Laboratory
 of Météo France

Laboratory of the
University of Genova

Laboratory
 of KNMI

 
 Progress Reports

Intercomparison  database (under preparation)

Final Report

 


About Instrument Intercomparisons

Comparison of sensors, instruments and equipment, which are operationally applied for measuring meteorological variables, are important means of determining their performance characteristics under in-situ (field) conditions. If required, additional tests are carried out in the laboratory.

For the organizational preparation of these tests, carried out under the auspices of WMO/CIMO either regionally or globally, and especially for determining the test- and data evaluation- conditions as well as for developing the rules for participation at the intercomparison, the president of CIMO nominates recognized experts serving in an International Organizing Committee (IOC) which is established for each trial (see WMO-No. 8, informally called CIMO Guide ).

The results of intercomparisons are published in WMO’s Instrument and Observing Methods Report series (IOM Publications list).  These reports also contain guidelines for WMO Member countries on improving the data observed, and conclusions particularly useful for instrument developers and providers to improve, among others, the performance and /or the reliability of the equipment concerned.