The Jet Stream and Seasonal Weather Forecasting by Dr Hall
In the latest School of Geography seminar series, our School’s Dr Richard Hall delivered a talk on weather forecasting and the Jet Stream.
As part of student’s assessment, this week’s winning blog post out of all groups was written by Amelia Beswick, Sarah Caton, David Hayes, James Liken, Bailey Marchant and Declan Shaw and can be read below:
The Jet Stream and Seasonal Weather Forecasting
Dr Hall explained how the jet stream is a key factor in the UK’s weather. The ribbon of fast, meandering, fragmented air, steers the course of weather systems around the globe, separating the warm and cold air masses. The UK’s weather is determined strongly by the position and strength of the Polar Front Jet Stream as it points directly towards us. This can be demonstrated by the extreme weather conditions of 1976’s dry months, 2007’s wettest summer and 2010’s coldest winter for 30 years.
The movement of the Jetstream allows predictions and statistical models to be constructed by including influential factors such as tropical volcano eruptions and artic sea ice causing the stream to move north or southwards. Hall states the North Atlantic Oscillation determines the variability of the stream. A positive NAO creates a mild wet winter with a negative NAO providing the opposite. Statistical modelling has recently developed using NARMAX models which allow non-linear and stationary relationships to be predicted.
The NAO and Jetstream forecasting is critical in determining daily and seasonal weather. The transport sector, insurance companies and agriculture are just some of the many who can benefit from this forecasting, preventing losses such as those in 2010, where £280 million/day was lost due to critical weather conditions.