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Climate Change Services

WMO and Climate Change

Glacier retreat

Glacier retreat (Image: dsearls)

The World Meteorological Organization (WMO) is the UN system’s authoritative voice on the state and behaviour of the Earth’s atmosphere including its interaction with the oceans, the climate and water resources. Its leading role in the coordination of international climate issues dates back to 1929 when the International Meteorological Organization established the Commission for Climatology (CCl).

It was WMO that, in 1976, issued the first authoritative statement on the accumulation of carbon dioxide in the atmosphere and the potential impacts on climate. As a result, in 1988, WMO and UNEP jointly established the Intergovernmental Panel on Climate Change (IPCC) which has been critical in providing regular assessments of climate science, potential impacts of climate change and of policy options, including mitigation and adaptation to climate variability and change. Furthermore, WMO in cooperation with UNEP, FAO, UNESCO and its IOC (the Intergovernmental Oceanographic Commission) and the International Council for Science (ICSU) established the Global Climate Observing System (GCOS)  to ensure systematic observation for climate change studies.

WMO Climate Change Activities

Climate Change Assessments

Scientific evidence strongly suggests that the consequences of climate change are grave and have an adverse effect on societies, particularly in developing countries. It is therefore essential that decision makers are able to formulate their policies based on the latest unbiased, scientific data.  The WMO and UNEP established the IPCC in 1988. Its mandate is to assess the relevant research information on climate change available in peer-reviewed literature, journals and books. It provides scientific, technical and  socioeconomic information to the world community. The IPCC is currently working on its 5th assessment report which is due to be published in 2014.

[More in depth information] on the most recent climate change science can be found in the IPCCassessment reports.

Climate Change Research

WMO’s joint programmes such as the World Climate Research Programme (WCRP) play a crucial role in narrowing uncertainties, particularly in the determination of the rate of climate change, the impacts on regional scales where society and environment are most vulnerable and the occurrence of extremes and sea level rise.

[More in depth information] on the WCRP can be found on its website.

The Atmospheric Research and Environment Programme (AREP), which co-ordinates and stimulates research on the composition of the atmosphere and weather forecasting also contributes to climate change research. It does so specifically through its Global Atmospheric Watch (GAW). The GAW provides reliable scientific data and information on the chemical composition of the atmosphere, its natural and anthropogenic change, and helps to improve the understanding of interactions between the atmosphere, the oceans and the biosphere.

[More in depth information] on the AREP, including GAW can be found here.

Global Climate Change Data

In 2005, WCRP facilitated the collection, archive and access of all the global climate model simulations undertaken for the IPCC Fourth Assessment Report (AR4). This was called the Coupled Model Inter-comparison Project (CMIP). The third phase of CMIP (CMIP3) involved an unprecedented set of 20th and 21st century coordinated climate change experiments from 16 groups in 11 countries with 23 global coupled climate models. About 31 terabytes of model data were collected at the Program for Climate Model Diagnosis and Inter-comparison (PCMDI). The model data are openly available, and have been accessed by over 1200 scientists who have produced over 200 peer-reviewed papers.

Regional Climate Change  Data

CORDEX (the COordinated Regional climate Downscaling Experiment) is a WCRP-sponsored programme to organize an international coordinated framework to produce an improved generation of regional climate change projections  around the world. These projections can then be used to determine more accurate  regional climate change impacts  and therefore more appropriate adaptation  strategies than can be achieved with global projections alone.

[Technical information] on CORDEX and access to its products can be found at the CORDEX data archive

Climate Projections

A climate projection is usually a statement about the likelihood that something will happen several decades to centuries in the future if certain influential conditions develop. In contrast to a prediction, a projection specifically allows for significant changes in the set of boundary conditions, such as an increase in greenhouse gases, which might influence the future climate. As a result, what emerge are conditional expectations (if this happens, then that is  what is expected). For projections extending well out into the future, scenarios are developed of what could happen given various assumptions and judgments.

[More in depth information] on WMO projections can be found in the 4th Assessment report of the IPCC.

[More in depth information] on the scenarios used in WMO’s projections can be found in the IPCC Special report on Emission Scenarios



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