Rising sea levels, warming temperatures, heat waves, worsening air
quality and stresses on the water supply are issues the Southeast will
face over the next 20 years because of man-made climate change,
according to a report released Tuesday.
"The Southeast is a key
part of the problem," said Keith Ingram, director of the Southeast
Climate Consortium and a professor at the University of Florida. "With
26% of the total population of the U.S. living there, the region emits
25% of the country's total carbon dioxide emissions."
Ingram spoke at a press conference in Gainesville, Fla., where the report was released.
The report, titled Climate of the Southeast United States: Variability, Change, Impacts and Vulnerability,
is part of the National Climate Assessment, an analysis mandated by
Congress as a comprehensive national look at the effects of climate
change.
Among the projected impacts of climate change in the Southeast:
•
Average annual temperatures are projected to increase through the 21st
century. Some areas are expected to warm by as much as 9 degrees.
•
Temperatures exceeding 95 degrees are expected to increase across the
Southeast, and the number of heat waves is expected to jump by between
97% and 234% through the end of the century.
• Stresses on the water supply are projected to increase significantly over next 3 1/2 decades.
•
Average sea-level rise across the Southeast coast is expected
to be between 1 and 5 feet by the end of 21st century.
•
High-temperature stresses are expected to become more frequent,
damaging crops and driving dairy and livestock production north.
• Air quality is projected to decline and pollen counts to rise.
"Climate
variability is already affecting the southeastern U.S. and a changing
climate is projected to increasingly affect the region in the next 20
years and beyond," Ingram added.
"There are numerous efforts
already underway in the Southeast to mitigate and adapt to climate
change," said Lynne Carter, associate director of the Southern Climate
Impacts Planning Program at Louisiana State University. "Among the most
successful are efforts in several states to plan for sea level rise,
including incorporating the risk of sea level rise into statewide risk
planning."
"Much more can be done, from protecting our forests and
wetlands, which help store carbon, to improving the region's energy
efficiency, building codes and use of renewable energy," she said.
The
report reviewed data from Kentucky, Virginia, Arkansas, Tennessee,
North Carolina, South Carolina, Louisiana, Mississippi, Alabama,
Georgia, Florida, Puerto Rico and the U.S. Virgin Islands.
It’s been an unusually quiet season for hurricanes over in the
Atlantic this year, with relatively few storms forming and even fewer
making landfall in the U.S. But the western Pacific Ocean—where tropical
storms are called typhoons—hasn’t been anywhere near as lucky.
(Hurricanes, typhoons and cyclones are all tropical storms—the only
difference is where they happen
on the globe.) There have already been three Category 5 typhoons so
far, the most powerful, reserved for storms with sustained winds of over
157 mph (253 k/h). How unusual is that? The Atlantic hasn’t had a
Category 5 storm since Hurricane Felix in 1997, and hasn’t had a major
hurricane—Category 3 or above—make landfall since 2005, the longest span
on record.
Now the western Pacific is about to get hit with another Category 5
typhoon—and it looks poised to break records. Super Typhoon Haiyan is
poised to bulldoze the central Philipines with maximum wind speeds that
appear to be among the strongest
in history. As of Thursday afternoon, Haiyan—which goes by the name of
Yolanda in the Phillipines—had estimated maximum sustained winds of 195
mph (314 k/h), with gusts over 220 mph (354 k/h). Only a few other
storms have ever had winds close to as strong as Haiyan, and no
hurricane in the Atlantic measures up. It’s the definition of a super
storm.
You can see just how massive Haiyan is in this gif from the National
Oceanic and Atmospheric Administration (NOAA), taken earlier on
Thursday:
As NOAA noted in a post, the conditions are perfect to fuel Haiyan’s fury:
The intensification of Super Typhoon Haiyan is being
fueled by “ideal” environmental conditions – namely low wind shear and
warm ocean temperatures. Maximum sustained winds are currently at 195
mph, well above the Category 5 classification used for Atlantic and East
Pacific hurricanes.
Though the storm will weaken slightly, it’s still likely to be
incredibly strong when it makes landfall in the Philippines Friday night
local time, where it threatens the city of Tacloban in Leyte province
with massive storm surges and mudslides. While the capital city of
Manila will likely be spared a direct hit, it will still experience
enough flooding to cause danger, especially in low-lying areas. From
then on, forecasters expect the storm to continue tracking toward the
Southeast Asian mainland, approaching Vietnam by the end of the weekend.
Even if Haiyan somehow falls short of being a record-breaker, the
death toll from the storm as it rakes across a relatively impoverished
country like the Philippines will almost certainly be high. A 2006
mudslide in the country’s Leyte province killed over 1,000 people—a
disaster that had less to do with the rains than with years of poorly
regulated mining and logging. Death tolls from natural disasters are as
much a matter of poverty and preparation as they are of wind speed and
rainfall. The Philippines—and the other countries in the path of this
epic storm—will need help.
Typhoon Haiyan Cuts a Path of Destruction Across The Philippines
Photo by Alexis DUCLOS/Gamma-Rapho via Getty Images
A new study finds that the oceans could be holding the missing heat from global warming.
The experts at the U.N.’s Intergovernmental Panel on Climate Change (IPCC) had a particularly pressing challenge as they prepared the newest assessment on global warming science, the first chapter of which was released in September. The problem was that the climate wasn’t acting the way they’d expected. In recent years, global greenhouse gas emissions had kept rising—hitting an all-time record in 2012. Yet even though the carbon concentration in the atmosphere gradually increased, passing the 400 parts per million threshold earlier this year, the planet’s average surface temperatures have remained pretty much the same over the past 15 years. The Earth hasn’t cooled—this past decade has still been the hottest on record—but temperatures haven’t risen as climate models predicted. Call it a “pause,” call it a “hiatus,” but the question is clear: where’s the heat?
Try the ocean. That’s one takeaway from a new paper published in Science today, one of a number of studies suggesting that the oceans depths seem to be soaking up the excess heat energy created by the accumulation of greenhouse gases. Researchers led by Yair Rosenthal at Rutgers University reconstructed temperatures in one part of the Pacific Ocean and found that its middle depths have been warming some 15 times faster over the past 60 years than at any other time over the past 10,000 years. It’s as if the oceans have been acting as a battery, absorbing the excess charge created by the greenhouse effect, which leaves less to warm the surface of the planet, where we’d notice it.
That means global warming is still happening, even if hasn’t necessarily been reflected in recent surface temperature changes. But there’s no guarantee that won’t change in the future. “We may have underestimated the efficiency of the oceans as a storehouse for heat and energy,” said Rosenthal in a statement. “It may buy us some time—how much time, I really don’t know. But it’s not going to stop climate change.”
The Science study isn’t the first to peg the oceans as a possible reservoir for the missing heat. An August study in Naturefound that a cooler Pacific ocean seemed to be offsetting global warming, and other studies have indicated that the oceans began taking on significant heat around the same time that surface warming began to slow down in 1998. That shouldn’t be surprising—the vast oceans carry 93% of the stored energy from climate change, compared to just 1% for the atmosphere, with melting ice and landmasses making up the rest.
But the Science study goes back further, using sediment core samples taken from the seas around Indonesia, where the Indian and Pacific Oceans mingle. By measuring the levels of magnesium to calcium in the shells of the Hyalinea balthica, a uni-celled organism buried in those sediments, the researchers were able to estimate the temperature of the middle-depth waters where H. balthica lived, between 3,000 ft. and 1,500 ft. (914 m and 457 m) below the surface. Over the past 10,000 years—a period of time known as the Holocene, when the plant’s climate was relatively stable and human civilization arose—the Pacific generally cooled, with a few exceptions, until about 1600, when ocean temperatures began gradually warming.
Over the last 60 years, however, water column temperatures increased by 0.32º F (.185º C)—roughly 15 times faster than any other time over the past 10,000 years. That might not sound like much of a change—surface temperatures rose about 1.4º F (0.78º C) over the past century—but the sheer scale of the oceans underscores just how much energy you need to heat it up even that much. The study is also a reminder that climate change won’t unfold steadily. Surface temperatures could remain stable for a number of years, as they have recently, only to spike suddenly.
The ocean depths still remain somewhat of a mystery to scientists, and they remain woefully understudied given the outsized impact they have on the planet’s climate. Initiatives like the XPRIZE’s new ocean science contests may help produce needed data about the undersea world, though they’ll take place against further budget cuts in the underappreciated National Oceanic and Atmospheric Administration. It’s become very clear that if we’re going to understand climate change fully—and predict it more precisely—we’ll need to understand the oceans much better than we do now. We may live on land, but our planet is still a blue one.
WASHINGTON -- Starvation, poverty, flooding, heat waves, droughts, war and disease already lead to human tragedies. They're likely to worsen as the world warms from man-made climate change, a leaked draft of an international scientific report forecasts.
The Nobel Peace Prize-winning Intergovernmental Panel on Climate Change will issue a report next March on how global warming is already affecting the way people live and what will happen in the future, including a worldwide drop in income. A leaked copy of a draft of the summary of the report appeared online Friday on a climate skeptic's website. Governments will spend the next few months making comments about the draft.
"We've seen a lot of impacts and they've had consequences," Carnegie Institution climate scientist Chris Field, who heads the report, told The Associated Press on Saturday. "And we will see more in the future."
Cities, where most of the world now lives, have the highest vulnerability, as do the globe's poorest people.
"Throughout the 21st century, climate change impacts will slow down economic growth and poverty reduction, further erode food security and trigger new poverty traps, the latter particularly in urban areas and emerging hotspots of hunger," the report says. "Climate change will exacerbate poverty in low- and lower-middle income countries and create new poverty pockets in upper-middle to high-income countries with increasing inequality."
The report says scientists have high confidence especially in what it calls certain "key risks":
-People dying from warming- and sea rise-related flooding, especially in big cities.
-Famine because of temperature and rain changes, especially for poorer nations.
-Farmers going broke because of lack of water.
-Infrastructure failures because of extreme weather.
-Dangerous and deadly heat waves worsening.
-Certain land and marine ecosystems failing.
"Human interface with the climate system is occurring and climate change poses risks for human and natural systems," the 29-page summary says.
Pennsylvania State University climate scientist Michael Mann, who wasn't part of the international study team, said the report's summary confirmed what researchers have known for a long time: "Climate change threatens our health, land, food and water security."
The report details specific effects of warming and how countries and people can adapt to some of them. Field said experts paint a dramatic contrast of possible futures, but because countries can lessen some of the harms through reduced fossil fuel emissions and systems to cope with other changes, he said he doesn't find working on the report depressing.
"The reason I'm not depressed is because I see the difference between a world in which we don't do anything and a world in which we try hard to get our arms around the problem," he said.
Homes built near a bridge sit destroyed due to Superstorm Sandy in Mantoloking, New Jersey October 31, 2012.
Earlier this month I stood outside the Babbio Center at the Stevens
Institute of Technology in Hoboken, N.J., looking out over the Hudson
River toward Manhattan. When Hurricane Sandy struck the New York
area on Oct. 29 of last year, the storm pushed the river over its
banks, and the narrow streets of the New Jersey city filled with water
like a bathtub. Standing next to me that day were Alan Blumberg and Tom
Herrington, ocean engineers at Stevens. Before Sandy hit, Blumberg and
Herrington had predicted the massive extent of the flooding that would
result from the storm and the damage that would be done to Hoboken,
which at its border along the Hudson sits just 4 or 5 ft. above the
river — even less at high tide, which happens to be when Sandy made
landfall.
Today the scientists and their colleagues at Stevens are trying to
improve those coastal-flooding models to better predict the precise flow
of floodwater for the next storm, in an effort to aid future evacuation
plans. But Blumberg and Herrington are painfully aware that, thanks to climate change
and rising sea levels, coastal cities like Hoboken and New York will be
in even greater peril when the next Sandy hits. “Many of the bulkheads
and seawalls here are only about 3 ft. above the water,” says
Herrington. “If you raise the sea level and the bulkheads stay the same,
you have more and more flooding for your infrastructure. Everything
we’ve built is too low.”
Here’s a fact about Sandy that might surprise you: when the storm made landfall in New Jersey on Oct. 29, it wasn’t actually
a hurricane. Its wind speed had fallen below the 74 m.p.h. sustained
velocity that’s needed to change a tropical storm into a hurricane.
Instead Sandy was officially a “post-tropical cyclone.” And while the
storm certainly dropped a lot of water
on the belt of heavily affected states between South Carolina and New
York — 7 in. or more in many places — it wasn’t the precipitation alone
that led to the devastating floods that followed in its wake, causing
more than $68 billion in damages. What made Sandy devastating was its
size, covering more than 1,000 miles, the coastal storm surges it
caused, and the way the force of the cyclone — which took an unusual
path almost directly at the East Coast — pushed the sea and rivers up
and over onto land, spilling out into streets and inundating nearby
infrastructure. At the Battery at the southern end of Manhattan, storm surges
of 9 ft. above normal were recorded. All told, Sandy broke 16 records
for the highest storm tide ever. Just about everything that followed —
the flooded homes and hospitals, the blackout that denied power to half
of Manhattan, the transportation mess — could be traced back to those
surges.
And that’s what makes the threat of another Sandy so grave. The storm
was the inevitable consequence of piling more and more people along
coasts that are threatened by rising seas.
(PHOTOS: Before and After Sandy, a Year of Recovery)
Scientists disagree on exactly how climate change will affect future tropical storms. (See this year’s hurricane season, which has featured virtually no storms after dire forecasts in the spring.) But here’s something we know for sure: 123 million Americans,
more than a third of the entire country, live in coastal counties, a
number that increased by 39% from 1970 to 2010. About 3.7 million
Americans live
within just a few feet of the sea at high tide, putting them at even
more extreme risk for coastal flooding. And the ocean they live next to
is rising. In New York, seawaters have risen by about 16 in. since 1778,
according to research by Tufts University geologist Andrew Kemp, while global sea levels have risen by a little over 7 in. on average over the past century. That translates to more devastating flooding. “For every inchfoot of sea-level rise, you have an additional 300 ft. of reach inland
for floods,” says Leonard Berry, director of the Florida Center for
Environmental Studies at Florida Atlantic University.
That rise has already had an effect on storms. A recent study published in the Bulletin of the American Meteorological Society found
that existing sea-level rise had already doubled the annual probability
of a Sandy-level flood in the New York region since 1950, and areas
outside the city, including the New Jersey shoreline, face an even
higher risk. “Today’s coastal infrastructure … is steadily losing ground
due to relative sea-level rise,” said William Sweet, an oceanographer
at the National Oceanic and Atmospheric Administration and a co-author
of the study. As temperatures continue to rise thanks largely to
man-made carbon emissions, so will sea level. In its most recent report,
the Intergovernmental Panel on Climate Change predicted
that sea level could rise 20 to 38 in. by the end of the century if
nothing is done to slow the pace of carbon emissions. Absent better
coastal protection, higher seas make even relatively weak storms a
danger — and turn big storms like Sandy into catastrophes. “It’s like
you’re trying to dunk a basketball, and someone just raised the court by
a few feet,” says Blumberg. “That’s how sea-level rise works.”
The costs will add up, especially if we keep adding people and property to those threatened coasts. A recent study in Nature Climate Change
predicted that average global flood losses could rise from
approximately $6 billion per year in 2005 to $60 billion to $63 billion
per year by 2050, thanks to the multiplying effects of population and
economic growth as well as climate-change-driven sea-level rise.
“There’s been just remarkable development along the coast,” says Scott
Knowles, a professor at Drexel University and author of The Disaster Experts: Mastering Risk in Modern America.
“It’s not that the storms are necessarily worse in any objective way.
It’s that we have put more people and property in harm’s way.”
(MORE:As Tropical Storm Karen Dissipates, the Debate Grows Over a Quiet Hurricane Season)
The easiest way to reduce the danger from future storms is to reverse
that shift to the sea, and move people and property away from the
coast. That’s happening in some places. New York City’s $648 million
Build It Back program will support
homeowners of flooded properties who don’t want to rebuild, and instead
want to move, while New York Governor Andrew Cuomo has a separate plan
to buy out property
in hard-hit Staten Island and return it to nature. But so-called
coastal retreat is likely to remain a last-resort choice, though the rising cost of flood insurance
could change the calculation for some. We’re not moving New York City
or New Orleans, and threat of floods doesn’t seem to be enough to
overcome the temptations of living by the water, even after Sandy showed
how destructive that water can be. “Let me be clear,” New York City
Mayor Michael Bloomberg said
in Sandy’s aftermath. “We are not going to abandon the waterfront. We
are not going to leave the Rockaways or Coney Island or Staten Island’s
South Shore.”
So if we’re going to keep living in harm’s way, we have to do our
best to reduce the harm. That means prioritizing resilience, which has
replaced adaptation as the term of choice for city planners. Resilience
means understanding that disasters like storms and floods will happen —
there’s no adapting them away — and what we need to do is build homes,
communities, cities and countries that can take the punch of a Sandy
without hitting the canvas for the count. It means being creative about
the challenges we’ll face, knowing that they’ll evolve in the future.
“Cities have a tendency to prepare for the thing they got hit by in the
past,” says Mitch Landrieu, mayor of New Orleans. “We have to be ready
for anything that might come our way, and be flexible about what we’ll
need to respond.”
New York City, which absorbed some of the worst of Sandy’s wrath, has taken that challenge seriously. Bloomberg proposed a
$20 billion plan earlier this year meant to toughen the city against
floods and storm surges. Much of that money would go to build flood
walls, levees and bulkheads — though nothing as extensive as the massive
seawalls that protect Dutch cities like Rotterdam,
which would likely be too expensive and too disruptive for New York.
But funds would also go to softer defenses like sand dunes, as well as
reinforcing the city’s power grid, which was shown to be vulnerable to
storms after Sandy. “If we’re going to rebuild, we should build back new
and better,” says Judith Rodin, president of the Rockefeller Foundation
and a co-chair of NYS 2100, a New York State panel tasked with
providing recommendations for Sandy recovery. “If we spend more on
prevention, we can avoid the billions we need to spend on recovery.”
That’s the goal, anyway. But the truth is that there’s no guarantee
that Bloomberg’s ambitious vision for a more resilient New York will
ever become a reality. The billionaire mayor will be leaving office
soon, and the money that plan requires — while much of it would come
from federal funds — could hold back his successor. And what’s scary is
that New York is far from the only coastal city to face such threats.
Low-lying Miami has more than $416 billion in assets at risk to
storm-related flooding and sea-level rise, the largest amount in the
world. As Jeff Goodell described in an excellent piece for Rolling Stone earlier
this year, Miami as it is now may be doomed. “Superstorm Sandy is a
measure of the way things will happen,” says Berry, of the Florida
Center for Environmental Studies.
A year after Sandy, the risk from coastal living just keeps rising,
while we struggle to keep pace. And we’ll pay the price — one way or
another.
Gregory KatzPublished: Oct 29, 2013, 11:48 AM EDTAssociated Press
Scheveningen, Netherlands
Hikers walk during a storm on the beach of Scheveningen, Netherlands on October 28, 2013. (Lex Van Lieshout/AFP/Getty Images)
COPENHAGEN, Denmark -- The Europe storm death toll has risen to 15
after Danish police say a driver was killed when he crashed into a tree
knocked down by violent gusts.
Monday's storm was one of the worst
in years in western and northern Europe. Authorities said Tuesday that
dozens were injured in Denmark as wind gusts up to 194 kph (120 mph)
swept across the country.
In Denmark, train passengers spent the
night in a sports facility due to fallen trees on the tracks. The storm
left a trail of uprooted trees, damaged buildings and collapsed
scaffoldings across the country.
Germany had six deaths, Britain five, Denmark two and France and the Netherlands had one each.
Tens of thousands of people were without power Tuesday in Sweden, Denmark, Estonia and Latvia.
Gusts
of 99 miles per hour (160 kph) were reported on the Isle of Wight in
southern England, while gusts up to 80 mph hit the British mainland.
Later in the day, the Danish capital of Copenhagen saw record gusts up
of to 120 mph (194 kph) and an autobahn in central Germany was shut down
by gusts up to 62 mph (100 kph).
All across the region, people
were warned to stay indoors. Hundreds of trees were uprooted or split,
blocking roads and crushing cars. The Dutch were told to leave their
beloved bicycles at home for safety's sake.
Despite the strength
of its gusts, the storm was not considered a hurricane because it didn't
form over warm expanses of open ocean like the hurricanes that batter
the Caribbean and the United States. Britain's national weather service,
the Met Office, said Britain does not get hurricanes because those are
"warm latitude" storms that draw their energy from seas far warmer than
the North Atlantic. Monday's storm also did not have an "eye" at its
center like most hurricanes.
London's Heathrow Airport, Europe's
busiest, cancelled at least 130 flights and giant waves prompted the
major English port of Dover to close, cutting off ferry services to
France. (MORE: Hurricane Central)
Nearly
1,100 passengers had to ride out the storm on a heaving ferry from
Newcastle in Britain to the Dutch port of Ijmuiden after strong winds
and heavy seas blocked it from docking in the morning. The ship returned
to the North Sea to wait for the wind to die down rather than risk
being smashed against the harbor's walls, Teun-Wim Leene of DFDS Seaways
told national broadcaster NOS.
In central London, a huge building
crane near the prime minister's office crumpled in the gusts. The
city's overburdened transit system faced major delays and cancellations
and did not recover even once the weather swept to the east.
A
nuclear power station in Kent, southern England, automatically shut its
two reactors after storm debris reduced its incoming power supply.
Officials at the Dungeness B plant said the reactors had shut down
safely and would be brought back once power was restored.
Play Video
The storm left Britain in the early afternoon and roared across the
English Channel, leaving up to 270,000 U.K. homes without power.
Trains
were canceled in southern Sweden and Denmark. Winds blew off roofs,
with debris reportedly breaking the legs of one man. Near the Danish
capital of Copenhagen, the storm ripped down the scaffolding from a
five-story apartment building.
Copenhagen's Kastrup Airport saw
delays as strong gusts prevented passengers from using boarding bridges
to disembark from planes to the terminals.
In Germany, in addition
to widespread rail disruptions, both Duesseldorf and Hamburg airports
saw many flights cancelled, stranding more than 1,000 passengers.
Thousands
of homes in northwestern France also lost electricity, while in the
Netherlands several rail lines shut down and airports faced delays.
Amsterdam's central railway station was closed due to storm damage.
Amsterdam
was one of the hardest-hit cities as the storm surged up the Dutch
coast. Powerful wind gusts toppled trees into canals in the capital's
historic center and sent branches tumbling onto rail and tram lines,
halting almost all public transport. Commuters faced long struggles to
get home. (MORE: Safety Tips for All Weather Events)
Ferries
in the Baltic Sea, including between Denmark and Sweden, were canceled
after the Swedish Meteorological Institute upgraded its storm warning to
the highest possible level, class 3, which indicates "very extreme
weather that could pose great danger."
Trains were canceled in southern Sweden, and many bridges were closed between the islands in Denmark.
London
Mayor Boris Johnson praised emergency workers for doing an "amazing
job" trying to keep London moving. He said his thoughts, along with
those of all Londoners, were with the victims and their loved ones.
By Jon ErdmanPublished: Oct 21, 2013, 8:12 AM EDTweather.com
Share
Tweet
3
Radar loop of May 20, 2013 Moore, Okla. tornadic supercell from 3:25 p.m. to 4:34 p.m. CDT. The location of Moore, Okla. is denoted by red box near the center of the loop. The location of the tornado is denoted by the debris ball of higher reflectivity headed toward Moore. The yellow arrow denotes the decaying thundershowers tracking toward the Moore supercell. (Credit: National Weather Service - Norman, Okla.)
Is it possible the Moore, Okla. tornado on May 20, 2013 turned violent thanks to adjacent, non-severe thundershowers?
Play Video
IWitness: Moore, OK Tornado
Autoplay
ON
OFF
IWitness: Moore, OK Tornado
'It Takes Your Breath Away'
All That's Left of Home Paid Off
Dr. Forbes Surveys Destruction
Tales of Survival in Moore
This was the question posed by Ryan Wade, a University of Alabama-Huntsville (UAH) severe weather researcher, at the annual meeting of the National Weather Association in North Charleston, S.C. on Oct. 15.
Wade was presenting findings from an investigation of supercell mergers and other storm-scale interactions in recent tornado outbreaks with fellow UAH researchers Todd Murphy and Dr. Kevin Knupp.
In the radar loop above from the National Weather Service in Norman, Okla. (hereafter, NWS-Norman), you can see the Moore supercell with a pronounced hook echo first developing as it passed northwest of the town of Newcastle.
Highlighted by the yellow arrow is a decaying cluster of weak thundershowers moving northeast toward the supercell.
Wade noted an outflow surge — a surge of stronger winds associated with the supercell's rear-flank downdraft — occurred just after supercell merged with the decaying thundershowers. The supercell's hook echo then became more pronounced, with a distinct debris ball signature (circular area of red/purple reflectivity headed toward Moore), indicative of wind-lofted tornado debris.
"Combining damage surveys with the radar characteristics of the Moore supercell indicate the Moore tornado intensified after the cell mergers," said Wade.
Specifically, Wade noted that EF4 and EF5 damage, shown by red and purple contours in the map below, occurred after this cell merger and subsequent outflow surge.
Damage swath from May 20, 2013 tornado. Color contours denote boundaries of EF0 (light blue), EF1 (light green), EF2 (yellow), EF3 (orange), EF4 (red) and EF5 (purple) damage. (Credit: National Weather Service - Norman, Okla./Google Maps)
Recent studies by Ryan Hastings, a research assistant at Penn State University, and Josh Wurman, founder of the Center for Severe Weather Research, have laid out cases of supercell and other storm-scale interactions leading to tornadogenesis.
"The outflow surge observed after the Moore supercell single-cell merger appears to be consistent with numerical simulations by Hastings," said Wade. "Outflow surges have been identified by Hastings as a key component to mesocyclone intensifications observed after cell mergers."
In simple terms, the theory goes like this. A gust front marks the leading edge of a thunderstorm's outflow winds, featuring winds spinning about a horizontal axis, like rolling a pencil across your desk. When a thunderstorm's updraft interacts with this gust front, the gust front's horizontal spin can be tilted into the vertical and stretched. Like the oft-cited example of a spinning skater pulling in their arms, stretching a vortex makes it spin faster.
In the Moore tornado example, that dying thunderstorm cluster may have triggered an outflow surge in the supercell, providing additional low-level spin to intensify the Moore tornado.
Wade did caution these are simply initial observations, made also by others through Twitter. A more in-depth examination of the data is needed to come to more concrete conclusions. "I'm sure the folks in Oklahoma are already working on detailed analyses of this case since it significantly impacted their community."
To be fair, NOAA's Storm Prediction Center mentioned the "potential for strong tornadoes" two days prior to the event. Given the magnitude of potential energy and wind shear, particularly in the lowest levels of the atmosphere, it's possible this supercell would have produced a tornado, perhaps even a violent one, without the interaction with the dying thundershowers.
"Cell mergers observed in the Moore supercell and violent tornado cases from the April 27, 2011 and March 2, 2012 outbreaks highlight the need to identify and analyze other cells in the vicinity of supercells for their possible impacts after merger occurrence," says Wade.
Adjacent, weaker thunderstorms may be the instigators of another destructive future tornado.
Chief Meteorologist Dr. Todd Crawford of Weather Services International (WSI), a part of The Weather Channel Company, says, "As the first shot of significant cold air spurs above-normal heating demand across much of the eastern United States, there are many questions regarding its staying power in the weeks and months ahead."
Crawford adds, "While we do foresee colder-than-normal temperatures across the Midwest into the mid-Atlantic and Southeast in November and potentially into early December, there is a risk of much milder temperatures heading into the New Year, especially across the western and southern United States."
To see a breakdown of the forecast details, watch the video above or scroll down for more information.
November Forecast
November Temperature Forecast
Much like we are seeing in the second half of October, an overall dip in the jet stream east of the Rockies is expected to bring below-average temperatures from the Midwest to the Southeast and Middle Atlantic. The coldest temperatures are forecast to be in the north-central states early in the month and the Southeast later in the month.
From the southern Plains to the Desert Southwest and Pacific Northwest, warmer-than-average temperatures are forecast in November. The greatest probability for above-average temperatures will be from Texas to portions of Arizona, California and Nevada.
New England is also expected to see a warmer-than-average November.
IWitness: Moore, OK Tornado
'It Takes Your Breath Away'
All That's Left of Home Paid Off
Dr. Forbes Surveys Destruction
Tales of Survival in Moore
