European Centre for Medium-Range Weather Forecasts

European Centre for Medium-Range Weather Forecasts
Formation	1975
Headquarters	Reading, United Kingdom
Website	http://www.ecmwf.int/

The European Centre for Medium-Range Weather Forecasts (ECMWF) is an independent intergovernmental organisation supported by 19 European Member States and 15 Co-operating States. At its headquarters in Reading, England, one of the largest supercomputer complexes in Europe is linked by high-speed telecommunication lines to the computer systems of the national weather services of its supporting states. The Centre's computer system contains the world's largest archive of numerical weather prediction data.

Objectives

ECMWF is renowned worldwide as providing the most accurate medium-range global weather forecasts to 15 days and seasonal forecasts to 12 months. Its products are provided to the European National Weather Services, as a complement to the national short-range and climatological activities. The National Meteorological Services of Member States and Co-operating States use ECMWF’s products for their own national duties, in particular to give early warning of potentially damaging severe weather.

ECMWF was established in 1975, in recognition of the need to pool the scientific and technical resources of Europe’s meteorological services and institutions for the production of medium-range weather forecasts and of the economic and social benefits expected from it. The Centre employs about 160 staff members and 70 consultants coming from Member and Co-operating States.

The primary purposes of the Centre are the development of a capability for medium-range weather forecasting and provision of medium-range weather forecasts to the Member States. The objectives of the Centre shall be to develop, and operate on a regular basis, global models and data-assimilation systems for the dynamics, thermodynamics and composition of the Earth's fluid envelope and interacting parts of the Earth-system, with a view to preparing forecasts by means of numerical methods, providing initial conditions for the forecasts, and contributing to monitoring the relevant parts of the Earth-system.

The main objectives of the ECMWF are:

• Development of numerical methods for medium-range weather forecasting
• Preparation of medium-range weather forecasts for distribution to the member states
• Scientific and technical research directed to the improvement of these forecasts
• Collection and storage of appropriate meteorological data.

Work and Projects

ECMWF uses the computer modelling technique of numerical weather prediction (NWP) to forecast the weather from its present measured state. The calculations require a constant input of meteorological data, collected by satellites and earth observation systems such as automatic and manned stations, aircraft, ships and weather balloons.

The data are fed into ECMWF's databases and assimilated into its NWP models to produce:

• medium-range forecasts, predicting the weather up to 15 days ahead
• monthly forecasts, predicting the weather on a weekly basis 30 days ahead
• seasonal forecasts up to 12 months ahead.

Over the past three decades ECMWF's activities and wide-ranging programme of research and development have played a pioneering role in the remarkable advancement of weather forecasting and data assimilation systems.^{[citation needed]} ECMWF has dramatically improved the accuracy and reliability of weather forecasting, working in collaboration with Member and Co-operating States, the European Union and partners such as the World Meteorological Organization (WMO), the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) and the European Space Agency (ESA).^{[citation needed]}

ECMWF, through its partnerships with EUMETSAT, ESA, the EU and the European Science community has established a leading position for Europe in the exploitation of satellite data for operational numerical weather prediction, and in the exploitation of satellite data for operational seasonal forecasting with coupled atmosphere-ocean-land models. The increasing amount of satellite data and the development of more sophisticated ways of extraction information from that data have made a major contribution to improving the accuracy and utility of NWP forecasts.^{[citation needed]} ECMWF continuously endeavours to improve the use of satellite observations for NWP.

Reanalysis

ECMWF makes significant contributions to support research on climate variability. ECMWF has pioneered an innovative approach known as reanalysis, which involves feeding weather observations collected over decades into a NWP system to recreate past atmospheric, sea- and land-surface conditions over specific time periods to obtain a clearer picture of how the climate has changed. Reanalysis provides a most comprehensive and accurate four-dimensional picture of our atmosphere and effectively allows monitoring of the variability and change of global climate, thereby contributing also to the understanding and attribution of climate change.

To date, and with support from Europe's National Meteorological Services and the European Commission, ECMWF has conducted two major reanalyses of the global atmosphere: the first ECMWF re-analysis (ERA-15) project generated reanalyses from December 1978 to February 1994; the ERA-40 project generated reanalyses from September 1957 to August 2002.

Operational forecast model

Main article: Integrated Forecast System

The ECMWF is best known in the United States for its global operational forecast model, known officially as the "Integrated Forecast System" but usually known informally as the "ECMWF" or "Euro". The model runs both in a "deterministic forecast" mode and as an ensemble. The ECMWF model runs every 12 hours and forecasts out to 10 days. The ECMWF model is primarily used as comparison against the Global Forecast System, which is based in the United States and is run by the National Centers for Environmental Prediction. However, unlike the GFS, which is in the public domain under provisions of United States law, the ECMWF model is proprietary and copyrighted. Nonetheless, a limited amount of output from the model has been publicly released through both the ECMWF and various sites.

Early warning of severe weather events

ECMWF’s strategy underlines its commitment to maintaining the current rapid rate of improvement of its global medium-range forecasts and products. The ECMWF strategy puts the early warning of severe weather as its principal goal. ECMWF can contribute to the development of strategies to mitigate and adapt to climate change. In particular, ECMWF’s emphasis on the provision of reliable predictions of severe weather can be seen as a key contribution to help society adapt to the dangers and threats associated with global warming. Also scientists and researchers around the world use ECMWF’s forecast products to monitor the environment and analyse climate change.

Forecasts of severe weather events are vital to warn authorities and the public, and to allow appropriate mitigating action to be taken. Early warnings, made a few days ahead of potential events, are of significant benefit, giving additional time to allow contingency plans to be put into place. The increased time gained by issuing accurate warnings of severe weather will be crucial to save lives, for instance by evacuating a large number of people from endangered areas (e.g. storm surges in the North Sea), or taking cautionary actions to avoid major threats to goods and services (e.g. extreme winds).

ECMWF's Extreme Forecast Index (EFI) was developed as a tool to identify where the EPS forecast distribution differs substantially from that of the model climate. It is an integral measure referenced to the model climate that contains all the information regarding variability of weather parameters, in location and time. Thus users can recognize the abnormality of a weather situation without having to define specific space- and time-dependent thresholds.

ECMWF's monthly and seasonal forecasts provide early predictions of events such as heat waves, cold spells and droughts, as well as their impacts on sectors such as agriculture, energy and health. Since ECMWF runs a wave model, there are also predictions of coastal waves and storm surges in European waters which can be used to provide warnings.

Members

  members

  cooperation agreement

The ECMWF is made up of 19 European countries:

• the 18 founding states of 1975: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, Turkey, United Kingdom
• 1 state joined after the 2010 convention revision: Iceland (April 2011)

The ECMWF has concluded co-operation agreements with other states: Bulgaria, Croatia, Czech Republic, Estonia, Hungary, Israel, Latvia, Lithuania, Macedonia, Montenegro, Morocco, Romania, Serbia, Slovakia, and Slovenia.

Site

ECMWF is based at Shinfield Park, Reading, England. It shared grounds with the UK Met. Office College until Summer 2002, before the college was relocated to Exeter ahead of the move of the Met. Office Headquarters from Bracknell in 2003. The land the Met Office College was on is now used by residential housing.

See also

• EUMETNET
• EUMETSAT

Further reading

• Woods, Austin (2006). Medium-Range Weather Prediction - the European Approach. Springer. ISBN 978-0-387-26928-3. 

External links

• Official Website
• ERA-15 reanalysis
• ERA-40 reanalysis
• ECMWF on TOP500.org