In 1922, the English mathematician, Lewis Fry Richardson was the first to apply mathematics to the dynamics of the atmosphere, which allowed predictions to be made about the weather. Unfortunately, being in a pre-computer age meant that the calculations would take so long that even with many people working to solve the equations, the answer would not be found before the next days weather arrived. Even Richardson himself determined that it would take 64,000 people to perform the calculations needed to provide a forecast in time. Despite this, his work is the basis for numerical weather prediction which is used in present day weather forecasting.
Computing starts to add up
The first step into the brave new world of computing happened more than 50 years ago when the Met Office acquired an electrical desk-calculator and the services of a mathematician specifically trained in computational methods. This allowed them to undertake trial meteorological computations. So it was, with such basic equipment, not even capable of automatic multiplication, the Met Office began to fulfil the dream of L F Richardson.
In the following ten years, a small number of staff had access to a 'real' computer owned by the catering company J Lyons. The Met Office realised that this computer had great potential to help them speed up the calculation of the equations, so vital in providing an accurate and timely forecast. Nicknamed 'LEO' short for Lyons Electronic Office, it was built in the 1950s and ran the first real business computer program. It was used to calculate the value of Lyons' bakery sales.
Bigger, better and faster
With glowing valves and copious amounts of paper tape the Met Office finally embraced the computer age in 1959 and purchased a Ferranti Mercury, which was nicknamed Meteor. Since then, the computers have been regularly replaced to match the requirements needed to run increasingly complex numerical models of the weather, and for handling the multitude of weather data from surface observations and satellites. Currently forecasts for the next 24 hours are correct on six days out of seven, and today's three-day forecasts are as accurate as one-day forecasts were 20 years ago.
This year, the Met Office has again upgraded its systems, from a pair of Cray T3Es to the NEC SX-6/8. This supercomputer has 12.5 times the overall processing ability of the Cray machines. This is roughly equivalent to 1,000 top of the range desktop PCs.
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| Ferranti Mercury, which was nicknamed Meteor. | Assistants in the Communications room receiving weather conditions from weather stations and weather ships around the UK. 02/11/1965 | NEC SX-6 supercomputer |
With the NEC SX-6/8 the Met Office aims to improve on its 86% accuracy rate for 24-hour forecasts. The extra power will also mean increased accuracy and detail in numerical weather prediction models. Using data available from a new generation of satellites, these models will provide improved forecasts of high-impact weather. Climate change predictions will become even more authoritative through increases in resolution.
