Another damn import from the USA

Record-breaking temperatures in March? Check. Drought conditions declared? Check. What is it people used to say, “when America sneezes, Britain catches a cold”….? http://www.youtube.com/watch?feature=player_embedded&v=HTAZue6ylZ8 Peter Sinclair (of Climate Denial Crock of the Week fame) has been a busy man: However, the thing that really struck me most forcibly in this second part of his brand-new presentation (go here for the back story) on recent weird weather, was the way in which the record-breaking warmth in the mid-west and eastern USA was – almost simultaneously – accompanied by record-breaking cold temperatures in the Rockies and on the west coast. However, it has not snowed as much as is normal; so even there the drought continues. Thus, the water level in Lake Mead has only been lower when the Hoover Dam was being constructed. So-called “sceptics” will probably argue that, quite literally, this sort of weirdness comes with the territory (i.e. the USA is a big place). Certainly, the UK simply isn’t big enough to have such extremes of weather in different parts of the country at the same time. However, surely, when one weird thing is followed by another, and another, and another (with no near-normal events in between), it is hard to avoid the impression that we are rolling a dice and getting six every time? Mathematicians will point out that each roll of the dice is an independent event and, no matter how many times you roll them and get a six, the chance of getting a six next time is always the same… But do not be fooled, we have loaded the climate dice, extreme weather of all kinds is now more likely – think of it as the Earth’s way of “letting off steam”..! However, the unwanted import is the Jet Stream – that fast-moving body of air high-up in the atmosphere that snakes around the northern hemisphere like some kind of deranged paper dragon in a Chinese New Year festival parade. Unfortunately, we cannot blame this import on some unfair trade agreement; or the vagaries of foreign exchange rates. We do not have a choice about receiving this import; what goes around comes around. I am almost inclined to say, “Can we please stop the World – I want to get off!” A few weeks ago, the BBC screened a programme entitled “Global Weirding” (featured in the above), in which Katharine Hayhoe points out that the increased frequency of extreme weather (as predicted by climate models) is an inevitable consequence of the fact that the atmosphere now has on average 4% more moisture than it did 40 years ago. However, in the process of interviewing a number of key meteorologists, Peter Sinclair puts the spotlight on the position, speed and sinuousity (i.e. “bendiness”) of the Jet Stream – all of which can be explained by one thing – the disappearance of summer sea ice from the Arctic: This single accelerating trend has reduced the temperature difference between Pole and Equator; which has slowed the Jet Stream down, which has made it more erratic. The extreme cold weather of our most recent European winter – which gave rise to almost unprecedented snowfall in Croatia and southern Italy – was caused by the Jet Stream setting up a blocking pattern; allowing winds to blow in from Siberia for days if not weeks on end… Then, in March, the position of the Jet Stream had changed, and this time the UK was on the southern side of it and so, for a while it was warmer in Aberdeen than it was in Athens. In the USA, you managed to go one better, you managed to have the extremes in temperature occurring in different places at the same time – all thanks to the position and speed of the Jet Stream. Unfortunately, I think we are all going to have to get used to weird weather. Thanks to the intransigence of oil company executives – and the mind control they seem to exercise over our politicians – anthropogenic climate disruption (ACD) is making weird the new normal.