94 in Alaska? Weather extremes tied to jet stream
A pattern of extremes — from global warming, to weather whiplash, to tornadoes.
This Thursday, May 30, 2013 image provided by KFOR-TV shows a bolt of lightning from storm clouds moving over Guthrie, Okla. The jet stream, the river of air high above Earth that generally dictates the weather, usually rushes rapidly from west to east in a mostly straight direction. But lately it seems to be wobbling and weaving like a drunk driver, wreaking havoc as it goes. (AP Photo/KFOR-TV)
But lately it seems to be wobbling and weaving like a drunken driver, wreaking havoc as it goes.
The more the jet stream undulates north and south, the more changeable and extreme the weather.
The most recent example occurred in mid-June when some towns in Alaska hit record highs. McGrath, Alaska, recorded an all-time high of 94 degrees on June 17. A few weeks earlier, the same spot was 15 degrees, the coldest recorded for so late in the year.
You can blame the heat wave on a large northward bulge in the jet stream, Rutgers University climate scientist Jennifer Francis said.
Several scientists are blaming weather whiplash — both high and low extremes — on a jet stream that's not quite playing by its old rules. It's a relatively new phenomenon that experts are still trying to understand.
Some say it's related to global warming, but others say it's not.
Upside-down weather also happened in May: Early California wildfires fueled by heat contrasted with more than a foot of snow in Minnesota. Seattle was the hottest spot in the nation one day, and Maine and Edmonton, Canada, were warmer than Miami and Phoenix.
People swim and sunbathe at Goose Lake in Anchorage, Alaska on Monday, June 17, 2013. Alaska's largest city and other parts of the state are experiencing a long stretch of higher than normal temperatures. The jet stream, the river of air high above Earth that generally dictates the weather, usually rushes rapidly from west to east in a mostly straight direction. But lately it seems to be wobbling and weaving like a drunk driver, wreaking havoc as it goes. The most recent example is mid-June where some towns in Alaska hit record highs. (AP Photo/Rachel D'Oro)
Consider these unusual occurrences over the past few years:
— The winter of 2011-12 seemed to disappear, with little snow and record warmth in March. That was followed by the winter of 2012-13 when nor'easters seemed to queue up to strike the same coastal areas repeatedly.
— Superstorm Sandy took an odd left turn in October from the Atlantic straight into New Jersey, something that happens once every 700 years or so.
And here is what federal weather officials call a "spring paradox": The U.S. had both an unusually large area of snow cover in March and April and a near-record low area of snow cover in May. The entire Northern Hemisphere had record snow coverage area in December but the third lowest snow extent for May.
"I've been doing meteorology for 30 years and the jet stream the last three years has done stuff I've never seen," said Jeff Masters, meteorology director at the private service Weather Underground. "The fact that the jet stream is unusual could be an indicator of something. I'm not saying we know what it is."
Rutgers' Francis is in the camp that thinks climate change is probably playing a role in this.
"It's been just a crazy fall and winter and spring all along, following a very abnormal sea ice condition in the Arctic," Francis said, noting that last year set a record low for summer sea ice in the Arctic. "It's possible what we're seeing in this unusual weather is all connected."
Other scientists don't make the sea ice and global warming connections that Francis does. They see random weather or long-term cycles at work. And even more scientists are taking a wait-and-see approach about this latest theory. It's far from a scientific consensus, but it is something that is being studied more often and getting a lot of scientific buzz.
"There are some viable hypotheses," Stanford University climate scientist Noah Diffenbaugh said. "We're going to need more evidence to fully test those hypotheses."
Rutgers University Climate Scientist Jennifer Francis talks about the jet stream in front of an animation of the fast flowing air current during an interview in Washington, on Friday, June 7, 2013. "It's been just a crazy fall and winter and spring all along, following a very abnormal sea ice condition in the Arctic," Francis said, noting that last year set a record low for summer sea ice in the Arctic. "It's possible what we're seeing in this unusual weather is all connected." (AP Photo/Jacquelyn Martin)
The jet stream, or more precisely the polar jet stream, is the one that affects the Northern Hemisphere. It dips down from Alaska, across the United States or Canada, then across the Atlantic and over Europe and "has everything to do with the weather we experience," Francis said.
It all starts with the difference between cold temperatures in the Arctic and warmer temperatures in the mid-latitudes, she explained. The bigger the temperature difference, the stronger the jet stream, the faster it moves and the straighter it flows. But as the northern polar regions warm two to three times faster than the rest of the world, augmented by unprecedented melting of Arctic sea ice and loss in snow cover, the temperature difference shrinks. Then the jet stream slows and undulates more.
The jet stream is about 14 percent slower in the fall now than in the 1990s, according to a recent study by Francis. And when it slows, it moves north-south instead of east-west, bringing more unusual weather, creating blocking patterns and cutoff lows that are associated with weird weather, the Rutgers scientist said.
Mike Halpert, the deputy director of NOAA's Climate Prediction Center, said that recently the jet stream seems to create weather patterns that get stuck, making dry spells into droughts and hot days into heat waves.
Take the past two winters. They were as different as can be, but both had unusual jet stream activity. Normally, the jet stream plunges southwest from western Washington state, sloping across to Alabama. Then it curves slightly out to sea around the Outer Banks, a swoop that's generally straight without dramatic bends.
During the mostly snowless winter of 2011-12 and the record warm March 2012, the jet stream instead formed a giant upside-down U, curving dramatically in the opposite direction. That trapped warm air over much of the Eastern U.S. A year later the jet stream was again unusual, this time with a sharp U-turn north. This trapped colder and snowier weather in places like Chicago and caused nor'easters in New England, Francis said.
But for true extremes, nothing beats tornadoes.
Parts of Oklahoma City experience extreme flooding after multiple tornado's passed through Central Okla. on Friday May 31, 2013 in Oklahoma City. A violent storm formed over the prairie west of Oklahoma City late Friday afternoon, dropped a tornado in a suburb and rolled into the state capital as viewers brave enough to remain above ground watched on statewide television. (AP Photo/Nick Oxford)
In 2011, the United States was hit over and over by killer twisters. From June 2010 to May 2011 the U.S. had a record number of substantial tornadoes, totaling 1,050. Then just a year later came a record tornado drought. From May 2012 to April 2013 there were only 217 tornadoes — 30 fewer than the old record, said Harold Brooks, a meteorologist at the National Severe Storms Laboratory. Brooks said both examples were related to unusual jet stream patterns.
Last fall, a dip in the jet stream over the United States and northward bulge of high pressure combined to pull Superstorm Sandy almost due west into New Jersey, Francis said. That track is so rare and nearly unprecedented that computer models indicate it would happen only once every 714 years, according to a new study by NASA and Columbia University scientists.
"Everyone would agree that we are in a pattern" of extremes, NOAA research meteorologist Martin Hoerling said. "We don't know how long it will stay in this pattern."
NOAA on the jet stream: http://www.srh.noaa.gov/jetstream/global/jet.htm
Jennifer Francis study linking Arctic sea ice loss to jet stream changes: http://bit.ly/1aAFM5g
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Hey, global warming is a reality. What has not been demonstrated convincingly is the anthropomorphic contribution to global warming and the environmental effect (very likely to be virtually nothing) of reducing manmade causes 5-10%. However, reducing the manmade releases of CO2 and other green house gases 5-10% over the next 10 years would almost certainly destroy the global economy and upset the balance of power in the world. Guess this is what the environmental wackos want. But we can't do too much too fast. Otherwise Al Gore et al won't get to line their pockets over all this stupidity. What really needs to be done is stop animals from exhaling and termites from farting.
We as humans consider ourselves super smart. Fact of the matter is, humanity has not been around long enough to presuppose what is going on with our planet. Earth is a dynamic, living planet. It has storms, ice ages, droughts and periods of global warm up. Recently there was a discovery of a human tunic, that predated previous examples of human activity, of the particular region. Where was that tunic found?, at the bottom of a glacier. The person may have fell in a crevice and ended up in the bottom, who knows?, none of us or our scientists were there to witness what happened. A logical person would come to the conclusion, this person was trapped in the ice, however may, and that current global temps have melted the glacier and re-exposed the tunic. That would also indicate the temperatures, in eons past, were also as warm as now. Long before the advent of the industrial revolution and it's so called effect of global warming. DUH!!!! I will not sit and say, we do not have an effect on our environment. I will say that modern man is naïve, in believing "his blink of an eye" existence, has even began to understand the scope of our earth and universe.
Why has there been no mention of the HARP program that is going on all around our world. Weather controlled by heating up the outer atmosphere. Millions of watts of power directed in concentrated patterns.
The direction of these arrays of microwave beams can be controlled to point in any direction..
What about these beams of energy?
What about the Chemtrails be sprayed all across the world?
Anyone care to handles these two questions
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