2011 Tornadoes Among Worst On Record

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2011 Tornadoes Among Worst On Record

On May 4, 2007, just after 9 p.m., storm chasers in rural Kiowa County, just outside the town of Greensburg, Kansas, reported the formation of a funnel cloud. Within 20 minutes, the tornado had grown to over half a mile in diameter. Sirens sounded and at 9:37 p.m., the National Weather Service in Dodge City, KS, issued a rare “tornado emergency,” used only to describe the rarest and most deadly tornadoes.

More severe than a warning, the amped-up rhetoric means significant, widespread damage with a high likelihood of fatalities is expected. Since its first use in Oklahoma in 1999, Greensburg’s tornado marked only the 13th time such a warning had been issued.

The Greensburg tornado was a monster, rated at an EF5—the highest rating on the Enhanced Fujita Scale, and the first given the designation on the new scale—producing winds in excess of 205 miles per hour. When it reached Greensburg, it was more than a mile wide, its ominous form illuminated by occasional lightning strikes.

Learn About UND's Recommended Plan of Action for a Tornado Emergency

By 10:05 p.m., when the first storm chasers reached the town just minutes after the tornado passed, they discovered people walking the streets in shock, wreckage heaped and scattered in every direction. More than 95 percent of Greensburg had been destroyed.

Greensburg’s tornado was a part of the May 2007 outbreak which produced 123 separate tornadoes before it ended on May 6. In all, 14 people lost their lives and estimates for the damage exceeded $250 million.

2011 Tornado Season (So Far)

On May 22, 2011, the sixth EF5-rated tornado (on the new scale) in the U.S. struck the small city of Joplin, Missouri. Unlike the people of Greensburg, who saw the storm build over several hours and are thought to have had significantly more time to prepare, the Joplin tornado became dramatically more violent four minutes before it struck town.

Tornado Myths:

  • MYTH: Areas near rivers, lakes and mountains are safe from tornadoes.
  • FACT: No place is safe from tornadoes. In the late 1980s, a tornado swept through Yellowstone National Park leaving a path of destruction up and down a 10,000 ft. mountain.
  • MYTH: The low pressure with a tornado causes buildings to "explode" as the tornado passes overhead.
  • FACT: Violent winds and debris slamming into buildings cause most structural damage.
  • MYTH: Windows should be opened before a tornado approaches to equalize pressure and minimize damage.
  • FACT: Opening windows allows damaging winds to enter the structure. Leave the windows alone; instead, immediately go to a safe place.

Learn more from the National Oceanic and Atmospheric Administration

Even more troubling, the Joplin tornado, which left more than 140 dead and almost a thousand injured, was the fourth EF5 tornado of the 2011 season, which lasts through July. Just a month before, in the April 25-28 tornado outbreak, three separate EF5 tornadoes struck the cities of Philadelphia, Mississippi; Hackleburg, Alabama; Huntland, Tennessee; Smithville, Missouri, and Shottsville, Alabama.

According to Xiquan Dong, an associate professor in UND's Atmospheric Sciences department, the 2011 has been an active season for tornadoes, but predicting future tornadoes, based on these recent storms, is not easily done. "People see a few powerful tornadoes and they think that it means this year will have many more powerful tornadoes, but that's not always the case."

Though the numbers are grim, the strength of these storms and their proximity in time does not necessarily portend more strong storms for the remainder of the 2011 season.

In fact, over the last 60 years, the average number of tornadoes reported annually by June 1 has ranged from between 500 and 700. As of June 1, 2011, the U.S. has experienced more than 1,200 tornadoes, putting us on track to surpass the all-time high of 1,884 tornadoes by the end of the year.

Why So Severe?

To listen to pundits and media personalities, one thing is clear: the evidence of more tornadoes in 2011 either emphatically proves or emphatically disproves the science and debate around the subject of climate change. This is not because the science in unclear, the majority of scientists have endorsed the position that changes to the Earth's climate are anthropogenic—that is, changes in temperature are caused by human interference in the environment. As the American Association for the Advancement of Science stated in an official statement in 2006, "The scientific evidence is clear: global climate change caused by human activities is occurring now, and it is a growing threat to society ... The pace of change and the evidence of harm have increased markedly over the last five years."

What is not as clear is the connection between increased temperature and 2011's severe tornado season. According to Dong, observers need to keep in mind that while the 2011 Tornado Season has already been one of the deadliest and most active in recent memory, it does not necessarily prove direct causation from climate change. Rather, what the 2011 season "proves" is that the conditions this year are right for severe weather.

"People see more tornadoes, bigger storms and they think 'it must be climate change' but the data is more complicated." The fact remains, tornadoes are rare, and in some eyes, beautiful, natural events that are as difficult to predict as next week's headline. To attribute one severe season to climate change is usually a stretch.

At the same time, what scientists can say is that climate change can help contribute to the conditions that make severe weather more likely. The nuance in this debate complicates the discussion.

Facts about Climate Change and Tornadoes form Professor Dong


Driving through the town of Greensburg six months after the devastating tornado of 2007, it was apparent that if the town was ever to recover, the effort would require more than dollars, plywood and elbow grease—it would take the will to re-imagine the town.

And, this is exactly what residents did.

Taking the opportunity to rebuild the town, Greensburg chose to do so by requiring all new buildings to be LEED Platinum certified. With the highest concentration of LEED buildings per capita, Greensburg is home to five LEED Platinum buildings, one LEED Silver and one LEED certified. From 2008 to 2010 Greensburg was the subject of a program on TLC that documented the town's progress in remaking itself into a more sustainable version of itself. The town's new motto: Rebuilding ... Stronger, Better, Greener!

For residents of Joplin, parts of Alabama, and the many other places that have been and will be affected by a severe tornado season in 2011, there are many lessons in the experience of Greensburg.

Craig Garaas-Johnson, News & Features Editor

Learn more about the 2011 Tornado Season from the National Oceanic and Atmospheric Administration

Contact Professor Xiquan Dong

Contact Professor Mark Askelson

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