For many millennia, and especially in recent centuries, humans beings have demonstrated a callous disregard for the natural world. Interestingly, before the human population got so large, and human wealth grew seemingly without limit, and human energy needs became so great, Homo sapiens basically got away with their disrespect for Nature. I can't help but think that if humans had been taught a few really painful lessons along the way, maybe they would have thought twice about fucking with the natural world.
The lessons these heedless humans were taught—the dessicating droughts of 8200 years ago in the Middle East, the collapse of the Mayans, treeless Easter Island, the Little Ice Age, and so on—obviously didn't take. These conflicts with the natural world were were too localized, too few and far between, or not big enough to get their attention. And humans don't remember the past anyway.
Humankind's rise took place during the benign Holocene Epoch, which begins after the Younger Dryas cold spell about 11,600 years ago. No worries!
But now, finally, in the 21st century, Homo sapiens is going to get a really big lesson about the consequences of disrespecting Nature. Unfortunately, by the time a really big lesson comes along, it's far too late to take that lesson to heart and do better next time, because such a lesson is so devastating that there's not much left to start over with, if anything.
Today's subject is the increasingly bizarre behavior of the Jet Stream in Earth's northern hemisphere. I wrote about this once before in What Happened To Spring? (March, 2013).
It's hard to separate the wheat from the chaff in weather-related disasters. First, there are so many of them, and there are more all the time, which is no accident of course. If you are somebody who likes to worry about all this human-caused shit, I suggest you worry about the recent behavior of the Jet Stream. Nature's revenge has begun.
Consider The Independent's (U.K.) story Britain basks in sunshine at last. But is it all part of the same global pattern of freak weather?
What connects this weekend’s glorious summer weather with the record heatwave in Death Valley California, the devastating floods this spring in Germany, the miserably cold March in Britain, unusually warm temperatures in Alaska this winter and many other examples of extreme weather around the world?
The answer according to some scientists is a high-altitude ribbon of fast-moving air in the northern hemisphere called the jet stream which appears to have changed from travelling in a relatively straight direction from west to east to a path that meanders widely between north and south.
A growing body of evidence suggests that something has happened to the jet stream, a river of wind which circumnavigates the globe at an altitude of between 5 and 7 miles and at speeds of up to 200 mph. Over the past few years scientists have noticed that it increasingly becomes “locked” in one position, sometimes for weeks at a time, bringing extreme heat or cold as well as droughts or floods.
This spring was a prime example. Instead of following its usual path to the north of Scotland, the jet stream shifted south for several weeks, bringing the coldest March in 100 years to Britain, as well as devastating rainfall and floods to central Europe and record high temperatures to Finland and western Russia.
Over the past week or so it has shifted north again, flipping to its more usual position over the top of Scotland, allowing a mass of warm air and sunshine to move over most of the British Isles from the Azores further south – bringing joy to Wimbledon’s centre court.
“The key question is what is causing the jet stream to shift in this way?” asked Professor Stephen Belcher, head of the Met Office Hadley Centre last month when he helped to organise a workshop of 26 experts to discuss the recent run of unusual seasons in Europe.
One possible answer lies in what is happening in the Arctic, which has seen temperature increases some two or three times higher than elsewhere in the world, and leading to dramatic and unprecedented loss of sea ice and melting of the massive Greenland ice sheet.
Scientists know that the jet stream is driven by temperature differences between the Arctic and latitudes further south. The smaller this temperature difference, the weaker the jet stream, and the weaker the jet stream the more likely it is to meander as travels around the northern hemisphere, said Jennifer Francis of Rutgers University in New Jersey.
“Certainly it all fits together. We are seeing big fluctuations in the path of the jet stream and where it gets into a meandering the north-south waves tend to stand still in one place, bringing extreme weather because whatever weather you are getting tends to hang around for a long time,” Dr Francis said.
“We see the west to east winds of the jet stream that are weaker and these winds are driven by the temperature differences between higher latitudes to the north and lower latitudes to the south. We know these temperature differences are becoming less marked,” she said.
“The evidence is piling up and at some time the circumstantial evidence will pile up enough to prove the case. The problem is that we don’t yet have enough long-term data from the real world to verify the connection, but the climate models seem to be telling the same story,” she added...
While Jennifer Francis of Rutgers waits for enough circumstantial evidence to pile up to convince 17 people whose opinion doesn't matter that the increasing decreasing temperature differential between the Arctic and lower northern lattitudes is fucking up the Jet Stream, I note that researchers have linked unusually heavy melting of the Greenland ice sheet in 2012 with the meandering Jet Stream.
The research, published today in the International Journal of Climatology, clearly demonstrates that the record surface melting of the GrIS was mainly caused by highly unusual atmospheric circulation and jet stream changes, which were also responsible for last summer's unusually wet weather in England.
The analysis shows that ocean temperatures and Arctic sea-ice cover were relatively unimportant factors in causing the extra Greenland melt.
How does one end a post like this one? Well, some of you may have heard about the heavy flooding in Alberta, Canada, and that too may be related to the "wobbly" Jet Stream.
Let's watch Nature teaching humans a lesson. Not that anybody will learn anything from it.
Very actual topic Dave, as always. I have given up on "educating" humans on climate change - it just does not matter.
Lately Toronto was hit by record rainfall:
http://www.cp24.com/cars-abandoned-go-train-stranded-as-record-rains-pound-t-o-1.1358702
Also Hawkkey Davies weather extremes weekly compilation can be recommended, see:
http://www.youtube.com/watch?v=tWdvHGzQJ7Y&feature=c4-overview&list=UU9-aSGgj7pVXFEnd-iFzVdA
Alex
Posted by: Alexander Ač | 07/09/2013 at 12:09 PM