Annual variations in the jet stream (video)

Posted on Mon 17 February 2014 in climate

The weather has been unusual in the past two months: extremely wet and windy in the UK whilst very cold and snowy in the United States. Such large-scale weather patterns are naturally linked to variations in the global atmospheric circulation. It is hence no surprise that there is much talk in the media about the so-called jet stream, which refers to the very strong winds which circle our planet at an altitude of about 10 km.

To get a better idea of what the jet stream looks like and how it varies, I hacked together a tiny Python module called to visualise the average position and strength of the jet stream in different months based on global circulation models. The result looks like this:

The data shown originates from the ECMWF ERA re-analysis model, which does not offer data for January or February 2014 yet (hence the video focuses on December). I cannot offer an interesting interpretation about this animation at present, I was just curious to look at the data.

If you spot something interesting in this video, please leave a comment below.