What's caused the UK's recent cold chill?

The rarity of snow in many areas of the UK has caused excitement and chaos amongst all. But what caused the UK's cold chill in January 2013?

It appears that there is a link between the UK's cold chills and the stratosphere. The stratosphere is the second major layer of the Earth's atmosphere, just above the troposphere. The stratosphere has a temperature gradient, so as altitude increases so does temperature.


Image courtesy of http://www.nc-climate.ncsu.edu/edu/k12/.ozonelayer 

 

But how does this affect the cold chills of the UK?

Well, it appears that stratospheric temperatures can have a dramatic effect on temperatures here in the UK. For weeks now, forecasters have noticed that the stratosphere has warmed considerably, and in recent times this has indicated cool temperatures are on the way. Such as in 2009 when a jump in the stratospheric temperature in January led to the UK being covered in snow by February.



However the two are not directly related, every fluctuation in stratospheric temperature does not result in the UK being frozen over and every time the UK is frozen over it is not always due to the stratospheric temperature but there is a link.

The stratospheric temperature is providing forecasters with a powerful tool of which to use when predicting weather conditions, however it can also throw the atmosphere into chaos and lead to very unpredictable weather, making it hard for forecasters to predict the outlook for the next 7 days. So, forecasters are facing a huge challenge. It is not until the effects of sudden stratospheric warming's wear off, that predictions can be accurate again.



Image courtesy of http://www.strudel.org.uk/blog/astro/000927.shtml