A dust storm approaches Phoenix, Arizona on July 5, 2011. Credit: Bryan Snider

Such strong dust storms — sometimes referred to as a haboob – is a visually-impressive weather phenomena that is common in arid regions such as the desert Southwest.  Dust storms frequently begin when a gust front or other strong wind loosens sand and dust from the Earth’s surface.  The particles are transported by the strong winds and are scraped along the ground, loosening more particles.

A dust storm approaches Phoenix, Arizona on July 5, 2011. Credit: Peter Busch

A dust storm approaches Phoenix, Arizona on July 5, 2011. Credit: Thomas Ballantyne

This dust storm was the result of a long-standing drought in the region that has been compounded by recent record heat.  As the heat builds and less precipitation falls, the ground dries out and a feedback cycle exacerbates the conditions over time.  When the summer monsoon winds build over the dry air, they dislodge the lose particles of dust and sand from the ground.

A dust storm approaches Phoenix, Arizona on July 5, 2011. Credit: M. Moulton

As these particles begin to shift and skip across the ground, they dislodge more particles and the smallest particles begin to remain suspended in the air.  The situation compounds over time, creating blankets of dust sometimes hundreds of feet thick.  This still image captured from the video of a local media reveals the depth of the storm as well as the magnitude, as shown against the backdrop of downtown Phoenix.

A dust storm approaches downtown Phoenix, Arizona on July 5, 2011. Credit: Raphael Torres

A stunning dust storm approaches downtown Phoenix, Arizona on the evening of July 5, 2011.

Even the interior of Sky Harbor Airport was not immune to the fine dust particles that seemed to infiltrate any open door, window, or gap in buildings in the region.

Reduced visibility at Sky Harbor Airport in Phoenix was not only a problem for aircraft, but even for passengers taking refuge in the terminals. July 5, 2011.

While weather radar is traditionally used to detect precipitation, it has also been used to detect many other phenomena.  Now we can add dust storms to the list.  Imagery from the evening revealed the sheer volume of dust elevated into the atmosphere, rising thousands of feet — perhaps as high as a mile — into the sky.  As the dust drifted over Phoenix from the south-southwest, the radar station based in Phoenix was able to detect it.

This animation reveals the extent of the dust storm as it approached downtown Phoenix, Arizona on July 5, 2011.

Radar scans of the atmosphere around Phoenix, AZ on the evening of July 5, 2011 reveal the volume of dust elevated into the atmosphere, rising thousands of feet into the sky.

A visible satellite image of the region reveals widespread thunderstorms blossoming throughout the region.  While the thunderstorms provided hope for widespread rain, many of the storms were relatively dry:  the rain that fell from the bases of the storms often failed to reach the ground, providing instead only the strong outflow of air that resulted in the dust storm that blanketed Phoenix.  However, some areas reported brief downpours following the dust storm, resulting in wet layers of mud coating all outdoor surfaces.

A visible satellite image reveals the widespread thunderstorm activity blossoming over the Southwest on July 5, 2011 that served as the source of gust fronts that kicked up dust, creating the ensuing dust storm. Credit: NOAA

The automated weather station at the Wichita airport registered a jump from 85 degrees to 102 degrees in a span of just 20 minutes, according to Stephanie Dunten, a meteorologist with the National Weather Service in Wichita.

The surge in temperatures began at 11:22 p.m. CST (12:22am CDT) when a pocket of air in the upper atmosphere collapsed to the surface, Dunten said. That sent winds of more than 50 miles an hour through portions of the city as the air hit the ground and spread out.  According to KAKE-TV, Sedgwick County 911 dispatchers received calls of trees and power lines down. The wind gust set off several alarm systems in the city.  Additionally, a middle school in the city lost most of the roof over its auditorium.

At one point, Westar reported more than 4,000 customers in the Wichita area without power.

The dynamics of a heat burst are surprisingly basic, though they aren’t observed very frequently – perhaps in part because their impacts are not widely felt: they traditionally strike a relatively small area. Heat bursts generally originate from a collapsing thunderstorm. As rain falls through the atmosphere at high elevations, it cools the air beneath it as it evaporates into the air. When this air cools dramatically, it becomes much more dense than the surrounding air, losing its buoyancy. This air then begins plummeting to the surface. As the air descends through the atmosphere, it encounters greater atmospheric pressure. This increase in pressure compresses the air molecules quickly, resulting in a spike in the temperature.

The crashing of the air to the surface also results in a dramatic increase in observed wind speeds as the air spreads out in all directions from the point at which it hit the ground.

As a result, the automated station at the airport registered a high temperature of 102 degrees at 11:42 p.m. CST.

Two years ago, a similarly dramatic heat burst struck Oklahoma City, resulting in temperatures spiking to 90 degrees after midnight on May 13, 2009.  Wind speeds topped 55 mph, resulting in widespread damage was widespread with small trees and limbs reported down throughout the city.

Heat bursts have been observed in other Plains states in recent years.   Kearney, Nebraska was impacted by a heat burst in on June 20, 2006 when the temperature went from 70 to 93 in minutes overnight and wind speeds topped 60 miles per hour.

More recently, on August 3rd, 2008, a heat burst in Sioux Falls, SD forced air downward in such a dramatic fasion that the wind speeds over 50 miles per hour and the temperature jumped from 70 to 101 in less than 20 minutes.

The Taurus rocket carried the “Glory” payload and lifted off around 2AM from Vandenberg Air Force Base in California.

Initial indications are that a protective shell that sat atop the rocket failed to deploy as expected which caused the satellite to be too heavy to reach orbit.

The loss of the satellite is reminiscent of a similar loss two years ago when a global warming satellite crashed into the ocean near Antarctica.  That satellite was also powered by a similar Taurus rocket.

While the remains of the doomed rocket and satellite have not yet been definitively located, NASA officials indicate it likely plummeted back to Earth not far from the location where the previous satellite crashed.

“We failed to make orbit,” NASA launch director Omar Baez said Friday. “Indications are that the satellite and rocket … is in the southern Pacific Ocean somewhere.”

The $455 million payload satellite named “Glory” was set to begin a three-year mission to analyze atmospheric particles which are believed to reflect and trap sunlight.  While some aerosols are produced by humans, the vast majority are produced by natural phenomena, including volcanoes, forest fires, and other disruptions.

NASA officials have already announced that it hopes the third time is a charm: it is scheduling a duplicate launch in two years.

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Over 17" of freshly-fallen snow collapsed the roof of the Minneapolis Metrodome-home of the Minnesota Vikings.

A blizzard for the ages collapsed one of the most iconic landmarks of metro Minneapolis on Sunday morning: the Metrodome. The home of the Minnesota Vikings and former home of the Minnesota Twins could not stand the weight of the 17.1″ of snow that had piled on the Teflon roof over the preceding 36 hours.

Over 17" of freshly-fallen snow collapsed the roof of the Minneapolis Metrodome-home of the Minnesota Vikings.

For the short term, the Vikings-Giants game that had been rescheduled for Monday night at the Dome will be played in Detroit instead. The NFL has promised free tickets to anyone who wishes to attend the game, as well as preferred seating at the 50-yard line for anyone who has tickets for the Metrodome game and wishes to make the frigid trek to Detroit.
For the longer term, the Metropolitan Sports Commission–the organization that manages the Metrodome, is considering all of their options to repair the roof.

The NFL has moved the upcoming Vikings-Giants game to Detroit and is offering free tickets to anyone wishing to attend.

The massive taurpaulin roof — nearly 10 acres in area — collapsed under the cumulative weight of over 17 inches of freshly-fallen snow.

The massive tarpaulin roof-nearly 10 acres in surface area-collapsed under the tremendous weight of over 17" of freshly-fallen snow.

Aerial photos show the roof tore in two places in the center and one near the edge of the roof.

Over 17" of freshly-fallen snow collapsed the roof of the Minneapolis Metrodome-home of the Minnesota Vikings.

The Metrodome’s roof is made of two layers of Teflon coated fiberglass fabric, and is an air-supported structure supported by positive air pressure. To maintain the differential air pressure, spectators usually enter and leave the seating and concourse areas through revolving doors, since the use of regular doors without an airlock would cause significant loss of air pressure. The double-walled construction allows warmed air to circulate beneath the top of the dome, melting accumulated snow.

A sophisticated environmental control center in the lower part of the stadium is manned to monitor weather and make adjustments in air distribution to maintain the roof. However, such technological efforts aren’t always sufficient to maintain the integrity of the roof.

This photo from several blocks away shows the flattened roof of the Metrodome-an unusual sight for residents used to the familiar inflated bubble appearing on the skyline.

The roof has deflated five times in the stadium’s history. On November 19, 1981, a rapid accumulation of over a foot of snow caused the roof to collapse, requiring it to be re-inflated. It deflated the following winter on December 30, 1982, again because of a tear caused by heavy snow. In the spring following that same winter, on April 14, 1983, the Metrodome roof deflated because of a tear caused by a late-season heavy snow, and the scheduled Twins’ game with the California Angels was postponed. On April 26, 1986, the Metrodome roof suffered a slight tear because of high winds, causing a nine-minute delay in the bottom of the seventh inning vs the Angels.

This file photo shows the interior of the Metrodome before the December 12, 2010 collapse of the Teflon roof.

Officials haven’t fully assessed the damage from the recent deflation, though they are optimistic the roof can be repaired before the next home Vikings game against the Chicago Bears on December 20th.

A massive iceberg drifts off the southern coast of Australia, promising tourists and beach-goers an amazing sight should it drift closer. Scientists expect the iceberg to slowly shrink and break apart in warmer ocean waters.

Large ice caps at the poles often shed large iceburgs every year, but rarely does such a large iceburg drift so near land, according to Australia’s Bureau of Meteorology.  This particular iceberg is believed to be a remnant of a larger sheet that was shed by the Ross Sea Ice shelf nearly 10 years ago.

This satellite photograph shows large icebergs calving from the larger antarctic ice sheet at the edge of the south pole.

The group of icebergs were thought to be heading to New Zealand but have now been blown off course.  That has not stopped a group of Australians who are determined to cash-in by trying to set up a floating bar on one of the icebergs.

The iceberg that has drifted toward Macquarie Island has taken a long path to get there. While it is proving quite a sight for islanders, scientists expect it to slowly shrink and break up in warmer ocean waters as the southern hemisphere summer looms.

The Australian Meteorology Bureau went as far as issuing a shipping alert late last week as a massive iceberg was drifting within 1000 miles of the southwestern coast of the country. This followed New Zealand’s similar alerts late last month when a slew of icebergs headed toward South Island, New Zealand.  Those have since drifted away from land.

This massive iceberg drifts off the coast of Macquarie Island south of Australia, promising tourists and beach-goers an amazing sight should it drift closer. Scientists expect the iceberg to slowly shrink and break apart in warmer ocean waters.

The largest iceberg is 12 miles long and 5 miles wide.  It is slowly drifting northeast toward Western Australia state.

Like others that have come before it, it is expected that this iceberg will break up as it enters warmer ocean waters.  Such events are not entirely uncommon and scientists state that such a singular event cannot be definitively tied to climate change.

This alarming sprialing light was photographed over Norway on December 9, 2009. Source: http://www.vg.no/

Upon first glance, many would think the image is simply a creation of an eager photoshop student, but the reports have been validated by hundreds of people who saw the same object.  Video clips have emerged to further substantiate the still images.

This alarming sprialing light was photographed over Norway on December 9, 2009.

It is believed that the spiral was caused by a malfunctioning Russian rocket that was launched from a submarine.  Military experts state that the spiraling nature of the light is characteristic of a rocket-propelled object that is not functioning as planned.

This image shows the aftermath of the strange spiralling light that was spotted over Norway on December 9, 2009. The wispy white trail supports the theory that the light was caused by a malfunctioning rocket.

SpaceWeather.com reports that a “no-fly” order was issued for the area on December 9th which would correspond to the period in which the Russian military may have been testing an inter-continental ballistic missile.

File image of a land-based mobile Russian inter-continental balistic missile (ICBM).

This explanation has not been confirmed by the Russian government, although it seems the most plausible given the images and video clips that have emerged.  Regardless of the cause, one thing is certain:  it caused quite an alarm not only for Norwegian residents, but people around the world.

Update [12/10/09:  08:15]:

The Russian Defense Ministry has confirmed the Russian Navy launched a Bulava ballistic missile on December 9, but will not officially confirm the missile as the cause of the spiral lights seen over Norway.

File: The Russian submarine Dmitry Donskoi launched an intercontinental ballistic missile on the morning of December 9, 2009.

The Russian Navy confirmed the missile was fired from the “Dmitry Donskoi” nuclear submarine (shown above), but would not confirm the submarine’s location at the time of launch.

Snow blankets a stretch of the Great Wall of China in this file photo. Chinese Government officials have claimed recent successes in seeding clouds to produce snowfall in and around Beijing as a means of alleviating drought.

While the seeding efforts were localized to the Beijing region, snowfall was reported in several provinces, including Liaoning,Jilin and Hebei.  Chinese media reports government officials as hailing the efforts as a success.  “We wont miss any opportunity of artificial precipitation since Beijing is suffering from the lingering drought,” the report quoted Zhang Qiang, head of the Beijing Weather Modification Office, as saying.

This effort comes on the heals of other claims of weather modification successes.  Moscow recently declared it would enjoy a winter without snow, as cloud seeding efforts were underway aimed at forming precipitation outside of city limits.  It is hoped that such efforts would sap the clouds of significant moisture before the clouds moved over Moscow, thus reducing the headaches caused by Moscow’s traditionally heavy urban snowfall.

Cloud seeding efforts aimed at producing precipitation has had a long, checkered history around the world.  While China is employing these efforts to alleviate a substantial drought, other similar precipitation-inducing efforts have been attempted as a means of weakening hurricanes, causing precipitation to fall earlier or outside of a given region, and enhancing snowfall on ski slopes.

This is not the first time the state-run media has made such a claim.  In 2008, the Chinese government openly acknowledged weather modification efforts aimed at reducing smog pollution before and during the Olympic Games.  While the smog was significantly reduced during the games, such results could not be specifically tied to the weather modification efforts, as other smog-reduction efforts were simultaneously employed, such as substantially reducing vehicular traffic in the city.

More recently, China induced snowfall in a similar manner last winter, resulting in highway closures and stranding of thousands of travelers.

Snow blankets the center of Moscow in this file photo from 2007. If the mayor of Moscow has his way, the city will look much different this winter.

The mayor of Moscow has pledged his full support to a plan to seed the clouds upwind from Moscow as a means of encouraging precipitation to fall from the clouds before they reach Moscow.  It is his hope that the clouds that then blanket the city will not result in the usual heavy winter snowfalls Moscow is so well known for.

The Mayor is planning to spend several million dollars to pay the Russian Air Force to fly over the city and spray a fine mist of particulate matter into the clouds.  The hope is that the particles that are sprayed will cause moisture to quickly condense on them, forming small cloud droplets or snowflakes much sooner than they would normally form.  This “fast-forwaring” of the snow-making process would cause the clouds to create snow that would then fall to the ground before the clouds ever arrived in Moscow.  The mayor contends such efforts would save the city millions in snow-removal costs and the quality of life improvement would be immeasurable.

Just last week, a mysterious cloud formation was spotted over Moscow.  Referred to as a “halo cloud” or a “UFO cloud,” the rare formation likely had a much more innocuous title as a “hole punch cloud.”  The cloud was filmed and the images quickly spread across the web, creating quite a buzz about its cause.  As reported earlier by MeteorologyNews.com, the cloud was likely a simple hole punch cloud, whose origins are somewhat mysterious, although several theories support the notion that such clouds form when a cloud is comprised of ice crystals and super-cooled water droplets that are disturbed.  The disturbance causes a quick transformation of the super-cooled droplets into ice which clings to existing ice particles and floats to the ground or sublimates.  The quick dissipation of the water droplets creates a void, or hole.

It thus seems reasonable that the disturbance that caused last week’s hole punch cloud could reasonably be assumed to have been efforts by the Russian Air Force to test out its most recent cloud-seeding efforts in anticipation of the upcoming winter.  The Russian military has offered no confirmation of such suspicion.

It was recently reported that Mayor Yury Luzhkov is no stranger to such grand efforts to manipulate nature. In 2007, the Russian government made a similar attempt at cloud seeding by dropping cement dust into clouds.  But that attempt led to disastrous results:  one bag of cement dust failed to dissipate in the cloud, instead falling to earth and crashing through the roof of a house.  In 2002, he led a project to reverse the flow of the River Ob in Siberia in an effort to help irrigate the region’s agricultural zones.  Scientists have responded that such efforts were impractical, although such failures have not stopped Luzhkov from trying his hand at further manipulations of mother nature.

Such cloud seeding efforts are not new.  Going back to World War II, many countries have attempted to seed the clouds to either generate precipitation where it was needed or to prevent precipitation where it is unwanted.  As recently as early 2008, it was rumored that the Chinese government was planning such weather modification efforts as a means of scouring the air of smog prior to the Olympic Games, as well as ensuring rain-free days for outdoor sporting events.  It is unclear if such efforts were employed or if they were successful.

A "hole punch cloud" as seen over Moscow last week. Such clouds are rare and awe-inspiring as their cause is still somewhat mysterious.

Hole punch clouds are often attention-grabbers, as they are relatively rare.  When they do form, they tend to persist and are large enough to be seen for miles around.

The foundation of a hole punch cloud is traditionally a mid- or high-altitude cloud type such as cirrus or cirro-stratus.  Such clouds generally form above 20,000 feet or so in the atmosphere.  The National Weather Service has explained that such clouds are frequently composed of both ice crystals and super-cooled water droplets – water that is below the freezing temperature but still exists in liquid form.  When such a delicate balance occurs, only a slight disruption of this delicate balance may lead to a striking result.

This hole punch cloud is a particularly vibrant example of both the foundational cloud form and the evaporation of the water droplets in the surrounding environment. Some hold punch clouds are even referred to as "crop circles in the sky."

A hole punch cloud photographed over Alabama in 2003. Photo Source: Gary Beeler, Warning Coordination Meteorologist, National Weather Service Mobile, Alabama.

Frequently, the ice crystals may slowly grow and expand at the expense of the liquid droplets.  But when the balance is disrupted, the droplets may freeze instantly and thus permit the liquid droplets in the environment to evaporate, resulting in a “hole” in the cloud.

Another hole punch cloud, this one photographed over Colorado in 2007. Photo source: Colorado Uerlings: http://www.neatorama.com

It is believed that a cloud may be disrupted in this manner when a a jet flies through the thin cloud layer.  Such a disruption may spur the quick freezing of liquid droplets and evaporation of other droplets.  This would create the void in the space in which the jet passed through the layer.

While the source of hole punch clouds may be somewhat uncertain, they are certain to cause quite a vigorous discussion.

UPDATE (10/19/09):  The cause of the Moscow hole punch cloud may have been discovered:  cloud seeding.  See Moscow Testing Cloud Seeding; Promises Winter Without Snow.

Wind turbines along the Buffalo Ridge in rural southwest Minnesota (2004)

A relatively new wind energy farm in central Wisconsin has created a newly-discovered, puzzling side effect:  interference with the local National Weather Service doppler radar.

The Butler Ridge wind farm was constructed in February of this year and contains a total of 36 wind turbines, each standing about 300 feet above ground level.  These windmills were build on a ridge line that is about 1100 feet above sea level, placing the turbines in an optimal location to benefit from the highest wind speeds in the region.  Coincidentally, the location is in the sight of the local doppler radar tower in Sullivan, WI that is approximately 30 miles south of the wind farm.

This image from April 1, 2009 displays the location and reflecdtivity of the wind farm 30 miles north of the radar site. Credit: NOAA

Doppler radar functions to detect atmospheric phenomena by sending out an electromagnetic signal and simultaneously “listening” for the signal to return if it is bounced off of an object.  Many objects will reflect the radar beam, most notably rain droplets, ice crystals, and snowflakes.  But as we reported earlier this year, doppler radar can also detect bats, birds, aircraft, surface traffic, and even tragedies like 9/11 and the Columbia disaster.  They are even believed to have the potential to alter the weather.

In the case of the Butler Ridge wind farm, the radar beam is being reflected by the large blades on the spinning turbines.  This electromagnetic energy is then reflected back to the radar dome and the radar detects the object.  The turbine blades then appear on the radar image.  This seemingly innocuous interference could have significant ramifications in the upcoming severe weather season though.

This image from the National Weather Service demonstrates how wind turbines can be mistaken for storms on doppler radar. Credit: NOAA

Doppler radar is arguably one of the most critical tools at the disposal of the National Weather Service when they look to provide timely watches and warnings of severe thunderstorms and tornadoes.  By examining the output of doppler radars, meteorologists are able to detect and forecast thunderstorms that may become severe and where they may track.  But if the radar image is masked by interference such as the wind turbines, it is feared that severe weather watches and warnings may be less robust.

The National Weather Service Radar Operations Center has enlisted the help of the wind energy industry to try to alleviate these problems in the future by locating the wind farms in places that would not interfere with such radar signals.  They have published an extensive analysis of the problem.  The map below displays the locations (in red) of the doppler radar sites that may be impacted.  The yellow regions are those in which the radar beam travels close enough to the ground that it could be impacted by windmills constructed in those regions.

This map displays the locations of all National Weather Service radar locations (red) and the regions in which the radar beam is low enough to the ground that it may be impacted by windmills (yellow). Credit: NOAA

Meteorologists may be able to write software code that is able to filter out this interference, but such work can be costly and time-consuming.  The primary concern is that filtering the data to remove such interference may also increase the risk of filtering out true radar echoes – those of actual storms that must be detected for public safety.

With the mushrooming popularity of wind energy around the country, this problem is one that is sure to warrant further study and creative mitigation attempts.