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"UKMET" redirects here. For the model, see Tropical cyclone forecast model.
Met Office
Current logo, as of 2009
Agency overview
Formed1854
JurisdictionUnited Kingdom
HeadquartersExeter
Agency executive
Parent agencyMinistry of Defence
Websitewww.MetOffice.gov.uk

The Met Office (originally an abbreviation for Meteorological Office, but now the official name in itself), is the United Kingdom's national weather service, and a trading fund of the Ministry of Defence. Part of the Met Office headquarters at Exeter in Devon is the Met Office College, which handles the training for internal personnel and many forecasters from around the world. The current chief executive is John Hirst.

History

The Met Office was established in 1854 as a small department within the Board of Trade under Robert FitzRoy as a service to mariners. The loss of the passenger vessel, the Royal Charter, and 459 lives off the coast of Anglesey in a violent storm in October 1859 led to the first gale warning service. In 1861 FitzRoy had established a network of 15 coastal stations from which visual gale warnings could be provided for ships at sea.

The development of the electric telegraph in the 1870s led to the more rapid dissemination of warnings and also led to the development of an observational network which could then be used to provide synoptic analyses.

In 1879 the Met Office started providing forecast to newspapers.

Connection with the Ministry of Defence

Following the First World War, the Met Office became part of the Air Ministry in 1920, the weather observed from the top of Adastral House (where the Air Ministry was based) giving rise to the phrase "The weather on the Air Ministry roof". As a result of the need for accurate weather information for aviation, the Met Office located many of its observation and data collection points on RAF airfields, and this accounts for the large number of military airfields mentioned in weather reports even today. In 1936 the Met Office split with services to the Royal Navy being provided by its own forecasting services.

It currently holds a quasi-governmental role, being required to act commercially, but also has remained an executive agency of the Ministry of Defence since April 1990. A branch of the Met Office known as the Mobile Met Unit (MMU) accompany forward units in times of conflict advising the armed forces of the prevailing conditions for battle, particularly the RAF. The Hadley Centre for Climate Prediction and Research and the National Meteorological Library and Archive are also parts of the Met Office.

Locations

File:Met Office HQ.JPG
Met Office HQ, Exeter

In September 2003 the Met Office moved its headquarters to a purpose-built £80m structure near Exeter Airport and the A30, in Devon, being officially opened on 21 June 2004—its 150th anniversary—by Robert May, Baron May of Oxford, from its previous location of Bracknell in Berkshire, and it has a worldwide presence– including a forecasting centre in Aberdeen, and offices in Gibraltar and on the Falklands. Other outposts lodge in establishments such as the Joint Centre for Mesoscale Meteorology (JCMM) at University of Reading in Berkshire, the Joint Centre for Hydro-Meteorological Research (JCHMR) site at Wallingford in Oxfordshire, and there is also a Met Office presence at many Army and Air Force bases within the UK and abroad. Royal Navy weather forecasts are generally provided by naval officers, not Met Office personnel.

The new building on the edge of Exeter

Forecasts

Shipping Forecast

One of the British stalwarts, the Shipping Forecast, is produced by the Met Office and broadcast on BBC Radio 4. The Shipping Forecast has long been of real interest to, and vital to the safety of, mariners traversing the Sea Areas around the British Isles. Less vitally, the Shipping Forecast has been the subject of both books and song lyrics.[citation needed]

Weather forecasting and warnings

The Met Office is responsible for issuing Severe Weather Warnings for the United Kingdom through the National Severe Weather Warning Service (NSWWS). These warn of weather events that may affect transport infrastructure and endanger people's lives. In March 2008, the system was improved and a new stage of warning was introduced, the 'Advisory'.[1]

Weather prediction models

Its main role is to produce forecast models by gathering all the information from weather satellites in space and observations on earth, then processing it using two IBM supercomputers with a variety of models, based on a software package known as the Unified Model. The principle weather products for UK customers are 36-hour forecasts from the newly-operational 1.5 km resolution UKV model covering the UK and surroundings (replacing the 4 km model), 48-hour forecasts from the 12 km resolution NAE model covering Europe and the North Atlantic, and 144-hour forecasts from the 25 km resolution global model (replacing the 40 km global model)[2]. A wide range of other products for other regions of the globe are sold to customers abroad, provided for MOD operations abroad or provided free to developing countries in Africa. If necessary, forecasters may make adjustments to the computer forecasts. This main bulk of data is then passed on to companies who acquire it. Data is stored in the Met Office's own PP-format.

Seasonal forecasts

The Met office has regularly made seasonal forecasts, but has, in February 2010, announced that they will cease the publication of them, althoughthey will continue as an experimental research product. In Spring 2009, they forecast that Britain would experience a "barbecue summer", but parts of the country in fact had much rain and relatively little bright sunshine. In the Autumn of 2009, they forecast a "mild winter", but the winter of 2009/2010 was one of the coldest experienced for many decades.

Supply of forecasts for broadcasting companies

In particular, two of the main media companies, the BBC and ITV produce forecasts using the Met Office's data. At the BBC Weather Centre, they are continuously updated on the latest information arriving by computer, or by fax and e-mail.[3][4] The BBC's new graphics are used on all of their television weather broadcasts, but ITV Weather use animated weather symbols. This is mainly how the public are informed of weather events which may affect day-to-day life. The forecasters at the BBC Weather centre are employed by the Met Office, not the BBC.

World Area Forecast Centre

The Met Office is also one of only two World Area Forecast Centres or WAFCs, and is referred to as WAFC London. The other WAFC is located in Kansas, USA but known as WAFC Washington. WAFC data is used daily to safely and economically route aircraft, particularly on long-haul journeys. The data provides details of wind speed and direction, air temperature, cloud type and tops, and other features of interest to the aviation community.

Volcanic Ash Advisory Centre

As part of its aviation forecast operation the Met Office operates the London VAAC[5]. This provides forecasts to the aviation industry of volcanic ash clouds that could enter aircraft flight paths and impact aviation safety. The London VAAC, one of nine worldwide, is responsible for the area covering the United Kingdom, Ireland, the north east Atlantic and Iceland. The VAAC were set up by the International Civil Aviation Organisation (ICAO), an agency of the United Nations, as part of the International Airways Volcano Watch (IAVW).[6] The London VAAC makes use of satellite images, plus seismic, radar and visual observation data from Iceland[7], the location of all of the active volcanoes in its area of responsibility. The NAME dispersion model developed by the Met Office is used to forecast the movement of the ash clouds 6, 12 and 18 hours from the time of the alert at different flight levels.

Air quality

Main article: UK Dispersion Modelling Bureau

The Met Office issues air quality forecasts made using NAME, the Met Office's medium-to-long-range atmospheric dispersion model. It was originally developed as a nuclear accident model following the Chernobyl accident in 1986, but has since evolved into an all-purpose dispersion model capable of predicting the transport, transformation and deposition of a wide class of airborne materials. NAME is used operationally by the Met Office as an emergency response model as well as for routine air quality forecasting. Aerosol dispersion is calculated using the UKCA model.

The forecast is produced for a number of different pollutants and their typical health effects are shown in the following table.

Pollutant Health Effects at High Level
Nitrogen dioxide
Ozone
Sulphur dioxide		 These gases irritate the airways of the lungs, increasing the symptoms
of those suffering from lung diseases.
 
Particulates
 		 Fine particles can be carried deep into the lungs where they can cause
inflammation and a worsening of heart and lung diseases

High performance computing

Due to the large amount of computation needed for Numerical Weather Prediction and the Unified model, the Met Office has had some of the most powerful supercomputers in the world. In November 1997 the Met Office supercomputer was ranked third in the world.[8].

Year Computer Calculations a second Horizontal Resolution (Global/local) Number of Vertical levels
1959 Ferranti Mercury 3Kflops (N.A./320 km) 2 levels
1965 English Electric KDF9 50Kflops (N.A./300 km) 3 levels
1972 IBM System/360 195 4Mflops (300 km/100 km) 10 levels
1982 CDC Cyber 205 200Mflops (150 km/75 km) 15 levels
1991 Cray Y-MP C90/16 10Gflops (90 km/17 km) 19 levels
1997 Cray T3E 900/1200 430Gflops (60 km/12 km) 38 levels
2004 NEC SX-6 2.0Tflops (40 km/12 km) 50 levels
2006 NEC SX-8 and SX-6 5.4Tflops (40 km/4 km) 50 levels
2009 IBM Power6 140Tflops (40 km/1.5 km) 25 km/1.5 km in 2010 70 levels

Weather stations

Reports (observations) from weather stations vary considerably. They can be automatic (totally machine produced), semi-automatic (part-machine and part manual), or manual. Some stations produce manual observations during business hours and revert to automatic observations outside these times. Many stations now also feature recent innovations such as "present weather" sensors, CCTV, etc.

Some stations have limited reporting times, while other report continuously, mainly RAF and Army Air Corps stations where a manned met office is provided for military operations. The "standard" is a once-hourly reporting schedule, but automatic stations can often be "polled" as required, while stations at airfields regularly report twice-hourly, with additional (often frequent in times of bad weather) special reports as necessary to inform airfield authorities of changes to the weather that may affect aviation operations.

Some stations report only CLIMAT data (e.g. maximum and minimum temperatures, rainfall totals over a period, etc.) and these are usually recorded at 0900 and 2100 hours daily. Weather reports are often performed by observers not specifically employed by the Met Office, such as Air traffic control staff, coastguards, university staff and so on.

Notable former Directors General and Chief Executives

See also

References

  1. ^ "Met Office warning colours". Metoffice.gov.uk. 2008-11-19. Retrieved 2010-05-15.
  2. ^ "Met Office Atmospheric numerical model configurations". Metoffice.gov.uk. 2010-05-05. Retrieved 2010-05-15.
  3. ^ "Producing Weather Broadcasts". BBC Weather. Retrieved 2010-05-15.
  4. ^ "How the weather is forecast". The Met Office. 1954-01-11. Retrieved 2010-05-15.
  5. ^ "London VAAC". Metoffice.gov.uk. 2008-11-19. Retrieved 2010-05-15.
  6. ^ "International Airways Volcano Watch". Icao.int. 2010-03-26. Retrieved 2010-05-15.
  7. ^ Overview of VAAC Activities presentation[dead link]
  8. ^ Mark Twain, Kevin McCurley. "United Kingdom Meteorological Office | TOP500 Supercomputing Sites". Top500.org. Retrieved 2010-05-15.
  9. ^ "Prestatyn Weather website". Prestatynweather.co.uk. Retrieved 2010-05-15.
  10. ^ "Reason and Light". New Statesman. Retrieved 2008-04-22.
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