The Cray XC40 supercomputer

The third and final phase of our supercomputer was successfully installed in December 2016; this was a hugely complex Government IT project which was delivered early and on budget. This supercomputer is some fifteen times larger than its predecessor, this is a major science infrastructure investment and will allow the UK to continue to lead the world in weather, climate and environmental science high-performance computing.

Our supercomputer consists of three main systems - an identical pair of machines and a single larger system in a new purpose-built data centre nearby. The twin identical machines provide a highly resilient capability for running time-critical operational weather forecasts, whereas the third system provides research, development and collaboration capabilities.

When commissioned, all three phases of our current supercomputer appeared in the top 50 of the world’s most powerful computers. As such the Met Office’s supercomputer capability is one of the most powerful in the world dedicated to weather and climate.

Facts and big numbers

Our three new Cray XC40 supercomputers:

  • Are capable of over 14,000 trillion arithmetic operations per second – that’s more than 2 million calculation per second for every man, woman and child on the planet.
  • Contain 2 petabytes of memory enough to hold 200 trillion numbers.
  • Contain a total of 460,000 compute cores. These are faster versions of those found in a typical quad-core laptop.
  • Contain 24 petabytes of storage for saving data - enough to store over 100 years worth of HD movies

This power allows the Met Office to take in 215 billion weather observations from all over the world every day, which it then takes as a starting point for running an atmospheric model containing more than a million lines of code.


The value of the supercomputer

The supercomputer is expected to enable £2bn of socio-economic benefits across the UK through enhanced resilience to severe weather and related hazards.

This includes benefits to aviation from better forecasting at airports, more sophisticated modelling related to flooding, more detailed information for energy markets and new climate impacts research to inform long-term planning.

Our supercomputer is already helping to unlock new science and to introduce even more detailed forecasts and advice. This information is critical to supporting UK economic growth, improving UK resilience to high-impact weather and crucial in saving lives.

Increased capability

We are utilising some of the new capability of the supercomputer by upgrading our weather models - extending forecast lead times, expanding the area covered by our UK model and improving the accuracy of our forecast in the prediction of showers.

Looking ahead, improvements are expected across all timescales (day-to-day, seasonal, long-term climate) over the lifetime of the supercomputer. Over the next year the supercomputer will allow us to run detailed model runs for the UK every hour instead of every three hours – giving us crucial and timely updates when extreme weather is approaching.

Because of improved science and increased computing power, today's four-day forecasts are as accurate as one-day forecasts were 30 years ago. Forecast accuracy should continue to increase as technology advances.

Crucially, the new supercomputer capability will allow groundbreaking new science to be undertaken including the next generation of climate projections for the UK.

The UKCP18 project - harnessing the latest science and supercomputing capabilities from the Met Office, combined with the expertise of the Environment Agency and Defra - will provide crucial information about how we can expect our climate to change over future decades. These projections help decision-makers assess the full range of risks from the changing climate and advise how we can adapt.

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