Hey there, time traveller!
This article was published 12/2/2014 (808 days ago), so information in it may no longer be current.
The United States is freezing and Britain is flooded. Clearly, Indonesia is at fault. That, in any case, is my layman’s interpretation of a report this week from Britain’s meteorological agency, the Met Office. It makes fascinating, if nerdy, reading that can be boiled down to a few basic conclusions:
• The extended, extreme weather on both sides of the Atlantic is connected in a kind of butterfly effect that began in the Pacific and ended in Europe.
• Persistent rains over Indonesia and a pressure system in the Pacific bent the Asian-Pacific jet stream north, which forced cold polar air south and dumped snow and sub-zero temperatures on North America. As the polar air spreads south and east to the Atlantic, it has bumped into warmer tropical air, creating a "temperature gradient" that generates storms.
• At the same time, a band of fast winds that blow high in the atmosphere over the equator happened to flip direction, from east-west to west-east, something it does about every 14 months in a process called "quasi-biennial oscillation." This has had the effect of super-charging the Atlantic Jet Stream, which starts over North America and acts as a conveyor belt to carry storms across to Ireland and Britain. Because this jet stream has been 30 per cent stronger than usual this winter, and had some big storms to carry, it has dumped a lot of very powerful rain storms at its destination.
Or, in the words of the Met Office report: "These extreme weather events on both sides of the Atlantic were embedded in a persistent pattern of perturbations to the upper tropospheric jet stream."
• The net effect is that southern England was doused with about 15 inches of rain over December and January, the most since accurate records began in 1910, and probably the wettest period in 248 years. No one storm was the worst on record, but they kept happening (and still are), saturating the ground so that every new rainfall brings instant floods. The Somerset levels of South West England are now a big lake, where 65 million tonnes of water are being pumped away at a rate of three million tonnes per day (only it keeps raining, so the pumping must continue). Along the Thames valley, quaint villages are under water. The railroad connecting London to the South West has been knocked out. People are getting around in canoes and dinghies. More rain is expected this week.
• This may or may not be due to climate change. It rains so much in Britain, and its weather patterns are so variable, that it’s impossible to prove a pattern or root cause. Yet an abundance of rain is exactly what climate change models predict for this part of the world.
Britons don’t blame Indonesia; they blame the government. Farmers are angry, for example, that the rivers of the Somerset levels, which are below sea level, weren’t dredged. The Environment Agency says that’s because of austerity — they wanted to dredge the rivers, but couldn’t because of budget cuts. Minister for Communities Eric Pickles blamed the Environment Agency for giving bad advice: "We thought they we were dealing with experts." People in need of sandbags blame the military for not supplying them. Environmentalists blame planners and developers for building in flood plains. The isolationist U.K. Independence Party blames spending on foreign aid, saying it should be used for flood defences instead.
Yet Brits should probably be thankful that the biggest rainfall in more than two centuries isn’t causing more damage. A similar but shorter storm in 1953, according to the Met Office report, left 307 dead and 24,000 properties under water. More than 160,000 acres of land were flooded as well.
In the December and January storms, no one was killed. Only 1,400 properties and 17,000 acres were flooded. (In recent days, however, Britain has taken a turn for the worse. A gravely ill seven-year-old boy died when he couldn’t get to a hospital. The number of flooded homes, meanwhile, has risen to about 5,000.)
"Given the overall volume of runoff, the amount of property flooding at the national scale was relatively modest," the Met Office report said. The difference is the result of defences built since 1953, including the world’s largest flood gate, the Thames Barrier, which protects London. Coastal barriers have been strengthened, too, which made a big difference when 52-foot waves struck in December. Chris Smith, the much-pilloried chairman of the Environment Agency, said in an article in the Guardian that his agency’s defences had saved 1.3 million homes from flooding.
"In a lifetime in public life, I’ve never seen the same sort of storm of background briefing, personal sniping and media frenzy getting in the way of decent people doing a valiant job trying to cope with unprecedented natural forces," Smith wrote. Still, it looks like he’ll take the fall. Prodded into a rare press conference yesterday, Prime Minister David Cameron refused to endorse Smith, other than to say it wasn’t "time for resignations" — yet.
Marc Champion is a Bloomberg View editorial board member.