Professor Julia Slingo answers questions on the Met Office
1. What is the Met Office and what are its main roles?
The Met Office is the UK’s national weather service provider and a world leader in weather and climate science. The main role is to protect life and property.
Thousands of weather forecasts are produced every day for the public, Government and commercial customers, including aviation, the energy industry and the media, including the BBC and ITV.
The Met Office also has responsibility for forecasting a range of weather-related environmental hazards, including the spread of fire, volcanic ash and airborne diseases for example.
The Met Office capabilities are driven by conducting scientific research and development, to increase our understanding and ability to observe, model and predict the atmosphere and oceans, from weather forecasting for a few hours and days ahead to climate prediction out to decades. Climate science evidence and advice is delivered to Government departments.
2. How does the Met Office collect data for its weather forecasting and how has this changed over the years?
Data for weather forecasts comes through a range of methods; these include aircraft, ocean buoys, weather balloons, land observations and satellites.
The biggest changes have been in the availability of satellites which have significantly improved weather prediction, as they provide observations of the Earth and its atmosphere from space. Advancements in computer technology and scientific understanding now mean that all of this data are processed to produce Met Office global forecasts four times a day. A trillion calculations a second are calculated by the supercomputer today, as observations from around the world feed in around the clock. This helps us to produce 3000 tailored forecasts and briefings each day – or almost one forecast every second of every day.
3. How has the accuracy of forecasting improved over the years?
The Met Office is consistently one of the top two operational weather forecasting services in the world. Accuracy has improved over recent decades, with a four day forecast today as accurate as a one day forecast 30 years ago for example. We have also been able to provide increasingly localised information by running our forecast models at higher resolution - so that we now provide guidance based on weather forecasts for the UK run at less than two kilometre horizontal grid spacing. We now also run a number of different forecasts to give advice on the probability of different weather outcomes. We publish a record of how accurate the forecasts are on our website.
4. How far ahead can the Met Office provide forecasts for and how accurate are these?
Detailed Met Office weather forecasts look ahead to the next five days. Our temperature forecasts are accurate to within two degrees 86% of the time. Beyond this timescale, our monthly forecast provides details for the UK a month ahead and this provides good guidance of weather trends and themes for the whole country. Meanwhile, our climate change projections can predict hundreds of years ahead, with various scenarios and uncertainties across the world. These are tested and validated by simulating past observed trends and ensuring that they capture key processes.
5. Why is it difficult to provide long range forecasts?
Quite simply, the further ahead you want to forecast the weather in detail, the greater the uncertainty. Long range forecasts are a developing area of the science but have already provided useful guidance for some parts of the world, such as the tropics and for forecasting tropical storms in the North Atlantic.
Long range forecasts are challenging for the UK because of the size and position of the country, which is at a ‘crossroads’ for various weather patterns. Recent research shows that long range forecasts are not deemed useful by the public as they cannot predict exact weather details weeks and weeks in advance. We now provide monthly outlooks to the public on our website.a
6. What different meteorological processes influence the daily weather forecast?
Our weather is affected by a number of interacting factors and processes, which we need to understand, model and predict to be able to make the daily weather forecast. These might include global-scale processes taking place over a number of years in the oceans, such as El Niño, to a number of very localised processes taking place in just a short time, such as the development of a thunderstorm. It is a very complex, but fascinating science!
7. As well as providing data for many of the weather reports we see, who else uses Met Office data and for what purpose?
Met Office forecasts are perhaps best known through the media, including the BBC, ITV and the web. However, this represents a small fraction of what the Met Office does. Our products and services are used by a wide range of customers. The UK Armed Forces rely on Met Office forecasts for all their operations around the world.
Warnings of severe weather events such heavy rain, snow or strong winds are provided to the Emergency Services around the UK. For the civil aviation industry the Met office is one of two World Area Forecast Centres – the other is in Washington, USA. This means we provide global forecasts of upper winds and temperatures for all flights throughout the world.
Many other industries use Met Office services: from marine forecasts for shipping, forecasts for the energy and transport industries, services for the retail and finance sectors, to weather impact advice for health services.
8. What work does the Met Office undertake to better understand climate change?
The Met Office Hadley Centre is one of the world’s leading climate science groups, and works in collaboration with other scientists to understand, monitor and predict climate change. It develops a number of observed climate records to understand and monitor past and current changes to the climate. We develop and run a climate prediction model of the atmosphere and oceans, based on knowledge of the climate system, to inform on future changes. This work benefits from the understanding that we gain from developing and running the weather forecast every day. We continue to improve the representation of key processes in the climate models, to quantify and reduce uncertainty in the future projections. We also conduct research to investigate the impacts of climate change and climate variability on critical resources such as water, agriculture, ecosystems, health and energy.
9. What changes are we likely to experience in Britain’s weather in coming years as a result of climate change?
Current predictions for later this century show that UK winters are likely to become milder and wetter. Summer weather is likely to be warmer but with less rainfall, although when the rain in summer does fall, it could be in the form of intense downpours.
10. What should a school geography club do if it wants to start recording weather data?
Recording the weather is a great way to learn about the changes we see across the UK day to day and groups do this in different ways. This can include taking photographs or keeping a weather diary. Measurements of rainfall, wind speed and direction, and temperature can be made using homemade or purchased equipment. These records can then be compared over time to identify trends or themes in the weather.
11. Is there a website where school can post their own weather records?
A new website called the Weather Observations Website (WOW) will launch this summer and invites clubs and schools to take part by submitting weather observations, from quick observations such as ‘it is raining here’, or uploading a photograph of the weather at a school to detailed observations made with weather station equipment. This means that observers do not need specialist equipment to take part. The website will also allow schools to share their information with each other to see how the weather changes over different parts of a town, city or county.
12. If young people wanted to pursue a career connected to weather and meteorology, how can they go about this?
Environmental sciences and geography are subjects that can be of great benefit and these can be followed by further study specifically in meteorology. A background in science such as physics or mathematics also provides a good start to a career in meteorology.
Julia was interviewed in June 2011.
Prof Julia Slingo's biography
Julia Slingo is the Met Office Chief Scientist. She is responsible for providing scientific and technical strategy; ensuring the organisation adheres to good scientific and technical standards, and directing and managing research and development with the Met Office. Julia also represents the office, on science and technology, across government.
Julia became Met Office Chief Scientist in February 2009. Before joining the Met Office she was the Director of Climate Research in NERC's National Centre for Atmospheric Science, at the University of Reading, where she is still a Professor of Meteorology. In 2006 she founded the Walker Institute for Climate System Research at Reading, aimed at addressing the cross disciplinary challenges of climate change and its impacts.
Julia has had a long-term career in climate modelling and research, working at the Met Office, ECMWF and NCAR in the USA. Her personal research addresses problems in tropical climate variability - its influence on the global climate; its role in seasonal to decadal climate prediction, and its response to climate change. Increasingly Julia's research considers the multi-disciplinary aspects of the impacts of climate variability and change on crops and water resources, and the need to improve the representation of weather systems and rainfall distributions in climate prediction models. She has successfully promoted the use of much higher resolution in climate models, required to capture these important processes and phenomena, and this has meant working with some of the world's largest supercomputers, such as the Earth Simulator in Japan.
- Contributed to the Stern Review on the Economics of Climate Change and to the Fourth Assessment Report of the IPCC
- Served as a member of several national and international committees, including the Met Office and ECMWF Scientific Advisory Committees
- In 2007 was appointed to the Joint Scientific Committee of the World Climate Research Programme
- Regularly involved in Royal Society activities, and in 2008 became the first woman President of the Royal Meteorological Society