WMO Anniversaries – Dates and Facts

There are important dates in every organization’s history – dates to celebrate and to remember achievements and the people behind them. In 2020, we mark the 70th anniversary of the WMO – it is a prelude to an even more important event: the 150th year of the International Meteorological Organization (IMO) and WMO, which will be celebrated by the global meteorological community in 2023. But some question that date as the early foundational events of international cooperation in meteorology are a bit obscure and cited differently in various historic reviews.

The history of the WMO reaches back in time through its predecessor, the IMO, making it one of the oldest international organizations, probably surpassed only by the International Telecommunication Union (ITU), established in 1865 as the International Telegraph Union, and the Universal Postal Union (UPU) established in 1874. However, some sources quote the establishment of the IMO as happening in 1873 (i.e., before the UPU), while others trace it back to August 1853, when the first International Meteorological Conference was held in Brussels. Furthermore, if we follow the strict definition of an international organization as “an organization established by a treaty or other instrument governed by international law and possessing its own international legal personality,” then neither date would be correct as some time was needed before the early forms of international coordination and cooperation took on the shape of an organization.

This article looks back at the history of IMO and WMO to shed light on the facts of their origin and to help us better understand the nature of this year’s 70th anniversary and the coming 150th anniversary of IMO/WMO in 2023.


The International Meteorological Organization (IMO)

Regardless of the exact dates of these early events, meteorology was one of the first areas where it was recognized that coordination and cooperation at the international trans-boundary level would be necessary. The first networks for systematic meteorological observations were set up in several countries around 1850 as the usefulness of weather observations in practical work became more apparent. This was particularly valid in maritime activities, which were then highly dependent on ocean and sea winds and currents.

The Second International Meteorological Congress
The Second International Meteorological Congress took place in Rome in April 1879. A key outcome of the Congress was the establishment of the International Meteorological Committee which was the predecessor of the WMO Executive Council. The new Committee agreed that the International Meteorological Organization would function more efficiently as a non-governmental organization, and therefore, no further Congresses were convened by IMO. Instead, a system of Conferences of Directors of Meteorological Services was established on a non-governmental basis.

Thus, at the initiative of Lieutenant M. F. Maury, a United States navy officer, the First International Meteorological Conference was held in Brussels under the chairmanship of A. Quetelet, the first director of the Royal Belgian Observatory. The main object of the conference was to achieve a uniform system of meteorological observations at sea. Twelve delegates, mainly naval officers from nine countries – Belgium, Denmark, France, Great Britain, the Netherlands, Norway, Portugal, Sweden and the USA – attended what was later described by Sir Arthur Davis “a highly significant occasion at the time, not only because of its successful outcome from the point of view of marine meteorology, but also because it demonstrated very clearly the important benefits to be derived for meteorology from international co-operation.” In this regard, there is good reason for the history of cooperation between state-led meteorological institutions to start from Brussels in 1853.

It took about 20 years for the next big step, the August 1872 international meteorological conference in Leipzig. It was a much bigger event with 52 persons in attendance. The invitation for the conference was sent to “the heads of Meteorological Institutes, other Learned Societies, as well as private scientific men and practical observers in the domain of Meteorology.” A list of 26 questions that “may be proposed to discussion and possibly be answered“ was sent to participants. It is not an exaggeration to say that these 26 questions formed the first agenda for the many years to come. While mostly technical, based on the pressing need for “increased uniformity in the methods of observation and publication”, several questions were also posed on important institutional and cooperation matters. For instance, question 24 asked, “Is it desirable that in each country there should be established one or more Central Institutions for the direction, collection, and publication of the meteorological observations?” Then question 26 inquired, “What Regulations should be adopted in order to carry into effect the Decisions and the Objects of the Meteorological Congress?” This last question, to a certain extent, remains valid today as we strive to produce better technical and other international regulations for interoperability and standardization.

The Leipzig conference was the preparatory event for the real thing a year later: the first International Meteorological Congress, convened by the Government of Austria in Vienna in September 1873. Invitations were extended through diplomatic channels to the governments of countries that had established national Meteorological Services. Virtually all accepted and 32 delegates from 20 governments took part. [Davis]. The discussions and decisions covered many technical and organizational matters. However, as cited by Sir Arthur Davis, “Most important of all was the acceptance on all sides of the need to establish a permanent international body in order to ensure continued progress in the science of meteorology and also to ensure that all nations could reap the practical benefits that such progress would make possible. In other words, the concept of an International Meteorological Organization was born”. In this citation, one should note the use of “the concept”, the author does not assert that the Organization was born – not yet. The seeds had been sown and the first international “body” had been established: a Permanent Committee with seven members (Bruhns, Buys Ballot, Cantoni, Jelinek, Mohn, Scott and Wild).

There is no doubt that the Vienna Congress in 1873 was the grand opening of the international era in meteorology. What is puzzling from a historical perspective is the various interpretation of the establishment of the International Meteorological Organization. The exact act of establishment is somewhat vague but, if we remember the definition of an international organization, the attributes needed were set between 1873 and 1879 for IMO. This was a period of active work of the Permanent Committee, which met several times – in September 1874 in Utrecht, in April 1876 in London and in 1878 again in Utrecht. One of its main tasks was to prepare the Second International Meteorological Congress, which was to be held in Rome in the spring of 1879. In Utrecht in 1878, the Permanent Committee prepared the agenda and programme for the Second Congress and, most importantly, drafted the Statutes of the International Meteorological Organization, which was hoped would emerge from the Rome Congress. The Statutes, while not a formal “treaty”, have been considered by some historians of meteorology as the birth date of the IMO – hence, several sources cite 1878 as its establishment year. The Second Congress, held in April 1879 in Rome, took the next key step – it adopted the Statutes of the IMO and instituted an International Meteorological Committee (IMC) consisting of nine members. Thus, some authors and historians point to the Rome Congress in 1879 as really marking the beginning of the first period of existence of IMO.

G. Svoboda, the Chief of the IMO Secretariat from 1938 to 1951 and the first Secretary-General of the WMO (1951-1955), distinguished the stages in the history of the IMO as follows:

  • Preliminary conferences, 1853–1872
  • Preparatory phase, 1873–1878
  • First period of existence of IMO, 1879–1914
  • Second period of existence of IMO, 1919–1939
  • Third period of existence of IMO, 1946–1950.

After the Second Congress in Rome, the intention for future events was to keep their inter-governmental element by inviting governments to designate delegates, but things went differently. The third Congress planned for Paris never happened. Instead, IMO convened non-governmental Conferences of Directors of the Meteorological Institutes/Services. “For a period of about seventy years, international co-operation in meteorology was firmly and efficiently in the hands of a [International Meteorological] Committee consisting of a group of non-governmental experts, and their co-opted successors. It was not until the creation of WMO in 1950 that the pattern of international co-operation in meteorology, started in Vienna in 1873 and in Rome in 1879 at the inter-governmental level, once more returned to that level” [Daniel].

Back to the original question of the year of establishment of the IMO. 1873? 1878? Or 1879? Many years later, the Fifth World Meteorological Congress in 1967 took a Solomonic decision with the perspective of organizing a centennial celebration of the international cooperation initiated at the First Congress in Vienna in 1873. The Resolution 11 of the Fifth Congress entitled “Celebration of IMO/WMO Centenary” stated clearly that the First International Meteorological Congress of delegates, held in Vienna in 1873, “marked the beginning of the work of the International Meteorological Organization.” Congress decided that “the centenary of the creation of the International Meteorological Organization shall be celebrated by WMO in 1973 under the title "IMO/ WMO Centenary Celebration". Thus, “exactly 100 years later, and in the same conference room in Vienna, the organization which was to succeed IMO held a centenary celebration attended by 210 participants, including representatives of 73 countries and 17 international organizations and in the presence of the President of Austria.” [Davis]

Our generation will continue the tradition by celebrating the 150th anniversary of the IMO/WMO. It will be a grand occasion to take note of the progress made in the international cooperation in weather, climate, water and environmental practice and science and to look at the challenges that lie ahead. Over the coming decades, the community will have to shoulder greater responsibilities in view of the formidable challenges posed by climate change, extreme weather, water resources scarcity, and environmental degradation. But we can learn from our predecessors who had their own grand challenges back when technological solutions were far less powerful than today.


The World Meteorological Organization

Sir Nelson K. Johnson, IMO President

Sir Nelson K. Johnson, IMO President (1946-1951), signing the Convention of the World Meteorological Organization in Washington in 1947.

With this year’s 70th anniversary of WMO, the historic facts are much clearer. The birth date of the WMO is 23 March 1950 – the day of entry into force of the Convention of the World Meteorological Organization. As written in Article 35 of the Convention, “the present Convention shall come into force on the thirtieth day after the date of the deposit of the thirtieth instrument of ratification or accession.” Thirty days before 23 March 1950, Iraq was the thirtieth country to deposit their instrument of accession. When the Convention came into force, WMO came into being. But again, this fact is not without an interesting history, which could be called “the history of the WMO Convention.”

The main difference in the transformation of IMO into WMO is foundational. Paul Edwards gives this concise description of the non-governmental character of the IMO: “The IMO case was typical of pre-World War II scientific internationalism. For seventy-five years, the organization remained a cooperative non-governmental association of national weather services. The principle of interaction was explicitly voluntary. As a result, IMO standards and policies functioned only as recommendations, which nations were at liberty to refuse or simply ignore.” Keeping the IMO business in the form of an association of weather services was a choice made after the Rome Congress in 1879. It was a pragmatic decision made to keep bureaucracy at a low level and avoid political interference in technical deliberations at a time when harmonization of methods and practices between countries would be better addressed in a purely professional discussion. After the 1920s, however, internationalization and globalization became the practice in many spheres necessitating political decisions by the government, such as transport and communications. IMO started to lag behind because of the voluntary nature of its decisions and resolutions. More and more meteorologists felt that the “thing impossible” (as said by professor Wild in 1875) – to collect weather and other meteorological data from thousands of stations, scattered over the globe – could become possible if only supported by governments, including financially, and with strong and binding international regulations and standards.

A compromise was reached when both sides agreed that the transition to the inter-governmental status, with affiliation to the UN in the future, would bring benefits for Meteorological Services and for the Organization. The move in this direction would not be compromised on two conditions: the world-wide character of the organization and its independence. The inclusion in the Convention of requirements for offices and bodies to be filled by Directors of Meteorological Services safeguarded the professional representation in the Organization.

After considerable animated discussion – the Conference held 31 meetings – the Convention was voted unanimously by representatives of 31 governments in October 1947. During the interim period from 11 October 1947 until 15 March 1951, IMO was still in place, preparing the final step of the transition to WMO. The last Conference of Directors was held in Paris from15–17 March. On the last day of that Conference, IMO ceased to exist opening the path for WMO to become the international organization responsible for coordinating meteorology at the international level. Two days later the First World Meteorological Congress opened. On 20 December the same year, the United Nations General Assembly adopted Resolution 531(VI) by which WMO became a Specialized Agency of the United Nations system.


A noble purpose

The First World Meteorological Congress took place in Paris, France in March/April 1951
The First World Meteorological Congress took place in Paris, France in March/April 1951.

The timeline and milestones of the formative years of IMO and WMO reveal a history of constant improvement and cooperation even in the most difficult times. This year’s 70th anniversary of the WMO and the forthcoming marking of the 150 years of the IMO/WMO in 2023 give us a reason to look back into this rich history with its technical, scientific, political and human aspects.

The men and women who catalyzed the unprecedented global cooperation, which led to breakthroughs and developments in many other areas, and who pioneered global networking and data sharing based on common goals and needs had a strong vision of a collaborative world. The seeds of this vision, which is still present in the WMO community, is apparent in the concluding remarks of Lieutenant Maury at the very first international meeting in Brussels in 1853:

We are taking part in a proceeding to which we should vainly seek for a parallel in history. Heretofore, when naval officers of different nations met in such numbers, it was to deliberate at the cannon's mouth upon the most efficacious means of destroying the human species. Today, on the contrary, we see assembled the delegates of almost every maritime nation, for the noble purpose of serving humanity by seeking to render navigation more and more secure. I think, Gentlemen, we may congratulate ourselves with pride upon the opening of this new era."


Celebrating 70 Years of Progress in Weather, Climate and Water



Report of the Proceedings of the Meteorological Conference at Leipzig, published by E. Stanford, Charing Cross, 1873

Final Report, Conference of Directors, Washington, 22nd September – 11th October 1947, Imprimerie la Concorde – Lausanne (Suisse), 1949

One Hundred Years of International Co-Operation in Meteorology (1873 -1973), A Historical Review; WMO - No. 345, 1973

Forty Years of Progress and Achievement, A Historical Review of WMO, Edited by Sir Arthur Davies, Secretary-General Emeritus, WMO; WMO - No. 721, 1990

J. Van Mieghem (Director Institut Royal Meteorologique de Belgique), International Co-operation and Meteorology: An Historical Review; reprinted from the Report of the Proceedings of the XIV Assembly of the International Association of Meteorology and Atmospheric Physics, 1967

A. Nyberg (Swedish Meteorological and Hydrological Institute), General Review of the Science of Meteorology during the Last 100 Years – Including the Role Played by IMO/WMO; Lectures presented at the IMO/WMO Centenary Conference, Vienna 1973; WMO - No. 370

Basic Documents No.1, 2019 Edition; WMO – No. 15


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