Instruments and Methods of Observation Programme


The Instruments and Methods of Observation Programme (IMOP) provides guidance on design, development and use of instruments and observation methods by setting standards and procedures for quality control. IMOP aims at standardizing the way observations are performed and documented and ensuring that instruments can be used in varying technical infrastructures and climatic conditions.
The ever-growing demand for higher resolution Earth system observations in both time and space and for the optimization of financial resources have obliged WMO Members to use observations from various sources, including from external and private data providers. 
The principal challenges for the Programme today are the wide diversity of instrument types and technologies, and the use of new technologies and approaches to measure and/or derive observational variables.
The transition from manual observations to automatic ones and the deployment of remote-sensing systems such as weather radars, wind profilers and satellites requires the development of guidelines on the use and performance of these systems.
Furthermore, WMO Earth system approach requires that the programme covers measurements for all the components of the WMO Integrated Global Observing System including all activity areas such as meteorology, hydrology, cryosphere, marine, space weather, etc.


The main long-term objectives of the Instruments and Methods of Observation Programme are:

  • Improving the quality and long-term sustainability of observations and measurements of meteorological, climatological, hydrological and related environmental variables through the coordination and promotion of the use of efficient methods and technologies to meet the observational requirements of operational and research applications; and 
  • Enhancing the effective and economic use of observing technology/systems through training and technology transfer in developing countries.


The Programme collaborates with instrument manufacturers – primarily through the Association of Hydro-meteorological Equipment Industry (HMEI) – the scientific community and other international organizations.  Over the years, it has partnered with other international organizations, such as the Bureau International des Poids et Mesures (BIPM), the International Organization for Standardization (ISO) and the direct involvement of INFCOM experts into metrology research such as with the European Metrology Research Programme (EMRP).


Established by the predecessor of WMO, the International Meteorological Organization, the Instruments and Methods of Observation Programme (IMOP) has coordinated the setting of technical standards and quality control procedures to provide guidance for the use of meteorological instruments and observation methods by Members for over a century. 


The Instruments and Methods of Observation Programme (IMOP) is being implemented by the Standing Committee on Measurements, Instrumentation and Traceability (SC-MINT) of the Commission for Observation, Infrastructure and Information Systems (INFCOM).

Key Publications: