The World Meteorological Organization

The World Meteorological Organization (WMO) is an intergovernmental organization with a membership of almost two hundred Member States and Territories divided into six regions: Africa, Asia, South America, North America, Central America and the Caribbean, South-West Pacific, and Europe. It originated from the International Meteorological Organization (IMO), the roots of which were planted at the 1873 Vienna International Meteorological Congress. Established by the ratification of the WMO Convention on March 23, 1950, WMO became the specialised agency of the United Nations for meteorology (weather and climate), operational hydrology and related geophysical sciences a year later. The Secretariat, headquartered in Geneva, is headed by the Secretary-General. Its supreme body is the World Meteorological Congress.

It is the U.N. system’s authoritative voice on the state and behaviour of the Earth’s atmosphere, its interaction with the land and oceans, the weather and climate it produces and the resulting distribution of water resources. As weather, climate and the water cycle know no national boundaries, international cooperation at a global scale is essential; WMO provides the framework for such international cooperation. The Organization plays a leading role in international efforts to monitor and protect the environment through its Programmes. In collaboration with other United Nations agencies and National Meteorological and Hydrological Services, WMO supports the implementation of a number of environmental conventions and is instrumental in providing advice and assessments to governments on related matters. These activities contribute towards ensuring the sustainable development and well-being of nations.


In Leipzig on August 1872, fifty-two meteorologists met to discuss the possibility of forming an international meteorological cooperation. “It is elementary to have a worldwide network of meteorological observations, free exchange of observations between nations and international agreement on standardized observation methods and units in order to be able to compare these observations” said C. H. D. Buys Ballot, a Dutch chemist and meteorologist. In his essay Suggestions on a Uniform System of Meteorological Observations, he described in detail what he thought was the way forward for meteorology as a proper science. The first International Meteorological Congress was organised a year later in Vienna.

An important outcome of the 1873 Vienna International Meteorological Congress was the formation of a Permanent Meteorological Committee – a group of seven distinguished meteorologists, all directors of meteorological services – who took on a number of tasks, one of them the drafting of the rules and statutes of an international meteorological organization. The committee completed the drafting at their meeting in Utrecht in 1878 and the International Meteorological Organization came into being at the International Meteorological Congress held in Rome the following year in 1879. A resolution of the Rome Congress was that an International Meteorological Committee be formed, with terms of reference similar to those of the Permanent Meteorological Committee that it replaced.

One of the decisions made at the Rome Congress was that an ambitious scientific enterprise be supported, this being a systematic study of meteorology and terrestrial magnetism in high latitudes of both hemispheres – a project which has come to be known as “The International Polar Year”. The project was significant in the history of IMO and WMO for two reasons: it was the first in a line of highly-organized international scientific programmes which continues to the present day; and the group of experts which was charged with organizing it and implementing it can be considered the first technical commission of IMO.

The establishment of the World Meteorological Organization (WMO) in March 1950, following the entry into force of its Convention, and the designation of WMO in 1951 as a specialized agency of the United Nations, heralded a new era for international cooperation in the field of meteorology, hydrology and related geophysical sciences.

The World Meteorological Convention was signed on October 11, 1947 and came into force on March 23, 1950. In the interim, the work of the International Meteorological Committee continued – in particular by making sure the many resolutions and recommendations of the Washington meeting were implemented. The Committee also secured recognition for itself by the United Nations as the preparatory body for the new organization and accordingly took part in relevant UN activities. The last meeting of IMO Conference of Directors was held in Paris in March 1951 and IMO formally became the World Meteorological Organization on March 17, 1951.

The World Meteorological Convention

In its Preamble, the CONVENTION OF THE WORLD METEOROLOGICAL ORGANIZATION states the following: “Considering the need for sustainable development, the reduction of loss of life and property caused by natural disasters and other catastrophic events related to weather, climate and water, as well as safeguarding the environment and the global climate for present and future generations of humankind”, “Recognizing the importance of an integrated international system for the observation, collection, processing and dissemination of meteorological, hydrological and related data and products”, “Reaffirming the vital importance of the mission of the National Meteorological, Hydrometeorological and Hydrological Services in observing and understanding weather and climate and in providing meteorological, hydrological and related services in support of relevant national needs which should include the following areas: (a) Protection of life and property, (b) Safeguarding the environment, (c) Contributing to sustainable development, (d) Promoting long-term observation and collection of meteorological, hydrological and climatological data, including related environmental data, (e) Promotion of endogenous capacity-building, (f) Meeting international commitments, (g) Contributing to international cooperation”, “Recognizing also that Members need to work together to coordinate, standardize, improve and encourage efficiencies in the exchange of meteorological, climatological, hydrological and related information between them, in the aid of human activities”, “Considering that meteorology is best coordinated at the international level by one responsible international organization”, and “Considering further the need for close cooperation with other international organizations also working in the areas of hydrology, climate and environment”.

It then continues with the first article enouncing that “The World Meteorological Organization is hereby established”. The purposes of the Organization, as exposed in ARTICLE 2 of the CONVENTION OF THE WORLD METEOROLOGICAL ORGANIZATION, are “(a) To facilitate worldwide cooperation in the establishment of networks of stations for the making of meteorological observations as well as hydrological and other geophysical observations related to meteorology, and to promote the establishment and maintenance of centres charged with the provision of meteorological and related services; (b) To promote the establishment and maintenance of systems for the rapid exchange of meteorological and related information; (c) To promote standardization of meteorological and related observations and to ensure the uniform publication of observations and statistics; (d) To further the application of meteorology to aviation, shipping, water problems, agriculture and other human activities; (e) To promote activities in operational hydrology and to further close cooperation between Meteorological and Hydrological Services; and (f) To encourage research and training in meteorology and, as appropriate, in related fields and to assist in coordinating the international aspects of such research and training”. The Convention then sets forth the organisational aspects of WMO.

As a specialized agency of the United Nations, WMO is dedicated to international cooperation and coordination on the state and behaviour of the Earth’s atmosphere, its interaction with the land and oceans, the weather and climate it produces, and the resulting distribution of water resources. As it is written on their website, WMO programmes facilitate and promote: the establishment of networks of observational stations to provide weather, climate and water-related data; the establishment and maintenance of data management centres and telecommunication systems for the provision and rapid exchange of weather, climate and water-related data; the creation of standards for observation and monitoring in order to ensure adequate uniformity in the practices and procedures employed worldwide and, thereby, ascertain the homogeneity of data and statistics; the application of science and technology in operational meteorology and hydrology to aviation, transport (air, land and maritime), water resource management, agriculture and other focus areas; activities in operational hydrology as well as closer cooperation between National Meteorological and Hydrological Services in states and territories where they are separate; and the coordination of research and training in meteorology and related fields.