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Thursday, 11 April 2013

Winter Weather – Press Clueless

What is the cause of the recent cold snap? For the climate change denial lobby, it justifies their welter of abuse and means that global warming isn’t happening. But for those capable of engaging brain and considering what goes on in the real world, the answer seems to lie in the significant melting of arctic ice during last summer, together with changing behaviour of the Atlantic jet stream.

Recently, the jet stream – winds in the upper atmosphere that direct the steady passage of weather systems from the UK’s south-west approaches and (hopefully) past the north-west corner of Scotland – has been misfiring badly, as I observed a while back. So weather systems are slowing down, or passing further south. In both cases this can bring colder easterly and north easterly winds.

Where the melting arctic ice comes in is the pushing south of a mass of colder air, helping the formation of “blocking” areas of high pressure, which prevent weather systems from taking their usual path. A “blocking” high pressure area was responsible for the December 2010 cold snap, and more of the same contributed to last summer’s repeated downpours.

Sun - utterly clueless. And wrong

This is not a difficult concept to grasp, unless of course you are a hack at a tabloid paper, in which case it becomes akin to rocket science. The idea of the Atlantic jet stream being pushed further south has been shown in the Sun as having it tracking over Africa. This is total crap. The Mail tries a little harder, but still doesn’t nail it. Fortunately, there are better resources online.

Mail - not as clueless or wrong as the Sun. But not right

A quick look at metcheck.com shows today’s visualisation of the Atlantic jet stream, and sure enough it is driving weather systems to the south, and hence today’s slow progress of a low pressure area with a lot of cold easterly winds on its leading edge. Now look at the jet stream forecast for next Wednesday, which shows a more normal track, although it could do with being yet further north at this time of year.

Graphics from metcheck.com

And what neither of these papers tell their readers is that it is just as easy for weather systems to get stuck in summer as in winter, and hence the grim heatwave recently experienced in Russia. Temperatures average out around the globe, so if one area gets colder weather, somewhere else is getting warmer conditions. That’s why the “it’s snowing so global warming isn’t happening” idea is so daft.

Jet stream in almost normal position

Also, the “what an ice age might look like” in the Sun is sheer idiocy (no change there, then). You only get ice age conditions when the ice is there all the time. And that isn’t going to happen. It’s sad to see millions of readers patronised in this way, but then, this is the title with a positive trust rating of just 10%. And 10% sums up the amount of accurate content in that article.

No specialist newsroom knowledge equals crap coverage, whatever the paper.

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