International collaboration is a sine qua non requirement to achieve success in weather forecasting, climate prediction and water resource management.
Weather and climate conditions have been key factors in almost all aspects of human evolution, from the development of agriculture to the rise and decline, and sometimes even collapse, of several civilizations as well as the major migrations that have shaped the world as it is today. Weather, and its prediction, has held fascination for humanity. For most of prehistory to just a few centuries ago, it was closely associated with gods or religion. The development of meteorological instruments in the 17th and 18th centuries - particularly, the barometer and thermometer - provided the foundation for a scientific approach, based on observations and analysis, to derive the fundamental laws of nature. This brought a major change. It soon became clear that systematic measurements with standardized instruments were essential to understand the behaviour of Earth's atmosphere. Since weather and climate ignore national borders, international collaboration is a sine qua non requirement to achieve success in this endeavour.
The first international observation networks were established in the 17th and 18th centuries. Invention of the electric telegraph by Morse in 1843 was a key technical development which allowed, for the first time, real-time exchange of meteorological observations, an essential element to enable predictions. This was followed by the establishment of several national weather offices in the 19th century and eventually the foundation of the International Meteorological Organization (IMO) in 1873. The work of IMO underlined the need for a comprehensive network of standardized observations and for the exchange of such data in real time on a global scale, both of which are still the core of WMO's approach in the 21st century.
Except for in its initial years, IMO was based on a on-governmental approach, but that progressively became a major limitation. The Berlin meeting of Directors in 1939, proposed radical changes, including the transformation of IMO into an intergovernmental organization. Nothing happened in the following years due to the outbreak of World War II. In 1947, the proposals were adopted in Washington by the signing of the Convention of the new World Meteorological Organization (WMO) by 31 States. After its ratification by 50 States, WMO was established in 1950 on 23 March - now celebrated every year as the World Meteorological Day. In 1951, WMO became a specialized agency in the United Nations System .
The early years
The work of WMO is based on an elaborate global infrastructure of observational, telecommunication and computing facilities, owned and operated essentially by the National Meteorological and Hydrometeorological Services (NMHSs) of its Members. WMO guides and facilitates cooperation among its Members by organizing the exchange of data and information and by providing technical assistance.
During its early years, WMO focused on supporting the standardization and exchange of observations through technical regulations and guides. A key initiative was the development, at the peak of the Cold War, of the World Weather Watch - the original WWW - in response to a UN resolution in 1963, supported by both the United States of America (USA) and the Union of Soviet Socialist Republics (USSR), on the peaceful use of outer space. This initiative confirmed meteorology as a model of international cooperation despite extreme political tensions. As a result, weather observations have since been exchanged without restrictions between all WMO Members.
WWW is one of the crowning achievements of WMO. It has subsequently expanded to encompass other observations - hydrological, climate, chemical composition of the atmosphere and more - as part of the WMO Integrated Global Observation System (WIGOS). This international cooperation has made it possible for today's six-day forecasts to be as reliable as a two-day forecast was 30 years ago. It is also at the core of the major improvement in the accuracy of early warnings which have contributed to the saving of millions of lives and the avoidance of losses in the trillions of US$, due to infrastructure damages and economic setbacks, over the last decades.
In response to the scientific progress in meteorology in the last 75 years, the interest of the public and its confidence in weather forecasts has grown considerably. Everyone has a weather app on their phone that they consult throughout the day. Weather bulletins remain among the most popular programming on television and radio. Weather forecasts are part of everyone's daily routine. But this extraordinary progress has raised expectations, that is the price of success.
All countries, without exception, even the largest ones, get much more from the free exchange of observations and research coordinated by WMO than what they contribute.
Early warning systems
Recurrent droughts in the Sahelian region, devastating tropical cyclones - Cyclone Bhola, in 1970 in what is now Bangladesh, caused more than 400 000 deaths - and many other weather-, climate- and water-related catastrophic events led WMO to prioritize "natural" disaster prevention, particularly by improving early warning systems, in the 1970s. Disasters are often the result of a lack of early warnings for those at risk and a lack of preparedness: statistics show that countries lacking effective early warning coverage experience eight times higher disaster mortality rates than those with comprehensive systems.
Following the adoption of The Sendai Framework for Disaster Risk Reduction 2015-2030 in 2015, WMO urged its Members to develop Multi-hazard Impact-Based Early Warnings, which could be more easily understood and acted upon by those at risk. Further, as the frequency and intensity of weather, climate and water extremes is significantly aggravated by anthropogenic climate change, WMO together with the Presidency of the 15th Conference of Parties (COP15) to the United Nation Framework Convention on Climate Change (UNFCCC) in Paris (2015) promoted the Climate Risk and Early Warning Systems (CREWS) as major initiative to support the development and strengthening of effective early warning systems in vulnerable countries. This was further reinforced since the call for Early Warning for All issued by the UN in 2022.
Many tens of thousands of lives are saved every year as a result of these improved early warnings systems which are also being better integrated into disaster prevention management.
Expansion of services and applications
WMO, as the UN's specialized agency responsible for operational hydrological activities, started coordinating the development of hydrological observing networks worldwide in 1972. This led the launch of the World Hydrological Cycle Observing System (WHYCOS) in 1993, the development of drought and flood forecasting and water resource management services.
In 1986, the Chernobyl Nuclear Power Plant accident led to the development of a system for predicting atmospheric trajectories of radioactive or chemical substances, coordinated by WMO in close cooperation with the International Atomic Energy Agency (IAEA). The efficiency of this system was demonstrated during the Fukushima Nuclear Plant accident.
More generally, the number and variety of weather and climate applications has exploded over last decades: the traditional applications still remain at the core of missions of NMHSs, such as services for agriculture to decide on planting, irrigation and
harvesting as well as advice on treatments, and aviation services to optimize fuel planning and in-flight safety. But the growth in new sectors, such as health, energy, tourism, retail industry, sporting events, transportation, etc, is exponential. The list is almost endless, since almost all socioeconomic activities are to a significant extent weather-sensitive and as such benefit from increasingly accurate predictions and warnings.
Research
None of this progress would have been possible without a strong support for research activities. In the area of atmospheric science, WMO has been coordinating research activities in the fields of atmospheric composition, weather modification, numerical weather prediction, and urban issues.
In particular, WMO has been providing essential information on the depletion of the ozone protective layer. The first assessment of the state of global ozone was published in 1976 and led to the Vienna Convention on the protection of the ozone layer (1985) and its Montreal Protocol (1987). As a result, today the ozone layer is on a path to recovery, though a few more decades will be required to fully achieve it. This is an outstanding demonstration of the effectiveness of a multilateral approach on global issues and of political decision-making based on solid scientific information.
In 1967, the decade-long Global Atmospheric Research Program (GARP) was launched. Led by WMO and the International Council of Scientific Unions (ICSU), now the International Council for Science (ICS), this program was perhaps the largest global scientific experiment of all times in all disciplines. It organized several field experiments that contributed to a better understanding of the role of the tropics and of global atmospheric circulation, and its interactions with the oceans, and to a spectacular development of numerical weather prediction and climate modelling.
The World Climate Conferences
Climate - the average weather conditions over long periods of time - is an essential element for life on our planet and, of course, for human beings. WMO took a major initiative when it organized the 1st World Climate Conference (WCC-1) in 1979 in Geneva. WCC-1 led to the launch in 1980 of the World Climate Programme - to facilitate the analysis of Earth system variability and change, for use in a range of practical applications - and the World Climate Research Programme (WCRP), co-sponsored by ICSU (now the International Science Council (ICS)) and UNESCO . WCRP has played an essential role in coordinating and supporting global research on the climate system and the effects of human activities on climate. The magnitude of the challenge was such that no country could have achieved the same outcome in isolation. Global cooperation has been key to the progress made. Without WCRP's contribution, our understanding of the impact of human activities on climate would be much more limited and would not suffice to inform decision-making with respect to both mitigation and adaptation.
WCC-1 also led to the creation of the Intergovernmental Panel on Climate Change (IPCC), by WMO and United Nations Environment Programme (UNEP), in 1988, at the request of their Member States. About every six years, IPCC provides decision-makers with authoritative scientific assessments of climate change. IPCC reports go through an extremely rigorous review process, arguably the most thorough ever in such a complex multi-disciplinary scientific context. The Panel received the Nobel Peace Prize in 2007 for its contribution to building-up greater knowledge about climate change, and thereby contributing to a better, safer world. Thanks to successive IPCC assessment reports, there is now overwhelming scientific consensus with respect to climate change. The scientific evidence is so strong that it is no longer possible, in good faith, to deny it, nor the role of human activities. WMO is proud to have contributed to and supported IPCC since its creation.
The second World Climate Conference (WCC-2), organized by WMO in 1990, launched the Global Climate Observing System in 1992, to provide better observations of the climate system with a strong space-based component. Observations involve physical, chemical and biological properties, covering atmospheric, oceanic, hydrological and terrestrial processes.
Despite considerable progress in Earth observations and in scientific understanding of the climate system, practical application of this knowledge to inform decision-making was limited in a very large number of countries, including in most developed countries. Thus, the third World Climate Conference (WCC-3) in 2009, again led by WMO, unanimously approved the establishment of a Global Framework for Climate Services (GFCS) to develop climate prediction and services, based on the best scientific information, for various socioeconomic sectors. The initial focus of the GFCS was on agriculture and food security, water management, energy, health and disaster prevention.
The new context
When the UN system developed in the late 1940s and early 50s, specialized agencies were set up with very specific sectoral mandates: FAO for food and agriculture, WHO for health, WMO for meteorology and so on. Counterpart organizations were also in place at the national level. Such an approach served society well for several decades. However, many issues are trans-disciplinary and that sectoral approach created formidable silos, with fierce competition for visibility and resources. WMO was not immune: for example, even within WMO, different observing systems had been developed independently for traditional weather observations, for the chemical composition of the atmosphere, for the hydrological parameters, for the cryosphere, and for climate data. Also, activities linked to disaster prevention were scattered across several WMO programmes.
To address these structural shortcomings and to put its own house in better order, WMO developed cross-cutting approaches. The WMO Information System (WIS) provides an integrated approach in the area of data management and telecommunications for WMO programmes to share weather, climate and water information.
