Featured Research

from universities, journals, and other organizations

New Thinking Needed On Atmospheric Physics, Study Suggests; Balloon Experiments Reveal New Information About Sprites

Date:
October 17, 2002
Source:
University Of Houston
Summary:
An atmospheric phenomenon called "sprites" could be pumping 50 times more energy into the upper atmosphere than was previously thought, suggesting our understanding of the global atmosphere is incomplete, according to University of Houston space physicists.

HOUSTON, Oct. 14, 2002 – An atmospheric phenomenon called "sprites" could be pumping 50 times more energy into the upper atmosphere than was previously thought, suggesting our understanding of the global atmosphere is incomplete, according to University of Houston space physicists.

Sprites are large, brief flashes of light that occur very high in the atmosphere above large thunderstorms. Instead of discharging toward the earth like lightning, sprites soar upward above a thunderstorm and occur immediately following strong lightning strokes.

University of Houston physics professors Edgar Bering and James Benbrook, along with their students, collected sprite data during a balloon campaign in the summer of 1999 when several balloons equipped with special detectors flew high into the atmosphere – around 20 miles up – over Texas and Iowa. The experiments were intended to study the electromagnetic signature of the lightning strokes that produce sprites.

"One of the more interesting things we discovered is that every lightning stroke tries to produce a sprite in the sense that it produces a similar but weaker electrodynamic pulse in the mesosphere," Bering says.

The layers of the atmosphere consist of the troposphere, which extends from the ground to about nine miles up; the stratosphere, beginning just above the troposphere and extending to 31 miles high; the mesosphere, extending from the stratosphere to 53 miles high; and the thermosphere, extending beyond the mesosphere to about 372 miles.

Previous research has shown that most sprites are produced by positive cloud to ground lightning strokes, which are more rare than negative cloud to ground lightning strokes, Bering says. Negative cloud to ground lightning strokes are initiated by a large concentration of negative charge in the cloud base, which tends to induce an area of positive charge on the ground, resulting in a discharge of electricity – lightning. A positive lightning stroke is exactly the opposite, with a positive charge concentration in the cloud inducing a negatively charged area on the ground.

Bering and his colleagues also found that negative cloud to ground strokes produce a phenomenon that is not often observed from the ground, termed a sprite halo, which is basically a sprite precursor.

"We discovered that seven to ten times as many negative cloud to ground strokes produce sprite halos as do positive cloud to ground strokes. That, coupled with the fact that every cloud to ground stroke, positive or negative, tries to produce a sprite or sprite halo, indicates that the amount of energy being deposited in the mesosphere by these sprite processes and related processes exceeds what we thought the sprites did by a factor of 50."

Bering says that amount of energy is comparable to the amount of energy the sun pumps into that same volume of atmosphere above the thunderstorm in daylight hours.

Bering will present an invited talk on the research findings at the World Space Congress 2002, to be held Oct. 10-19 in Houston.

The closest the balloon flights got to sprite-producing thunderstorms was about 300 kilometers, or 186 miles, which limited the amount of useful data the scientists could collect, Bering says. He cautions that the experiments need to be repeated because the results depended only on observations from a few storms. However, he says the results of the balloon flights indicate our understanding of the mesosphere is incomplete.

"It means we actually have at certain times and latitudes about a factor of two discrepancy in the energy budget of the mesosphere. From the standpoint of global understanding of the atmosphere as a whole, a factor of two in an energy budget is nontrivial," Bering says.

While the mesosphere does not directly affect weather on earth, and the altitude is too high for precipitation-producing clouds, some researchers are attempting to use mesospheric weather as a tracker for global temperature change.

Bering says the 1999 data suggests two avenues for future studies.

"We need to get closer to the storms, which requires both more balloons and also is a matter of luck, and put additional data collection equipment on board the balloons," he says.

The National Aeronautics and Space Administration funded the 1999 balloon flights. Bering has submitted a proposal to NASA for additional balloon studies of sprites.

In January, Bering will begin a study of phenomena other than sprites when he sends three balloons into the air over Antarctica to investigate the electrodynamics of the polar ionosphere.


Story Source:

The above story is based on materials provided by University Of Houston. Note: Materials may be edited for content and length.


Cite This Page:

University Of Houston. "New Thinking Needed On Atmospheric Physics, Study Suggests; Balloon Experiments Reveal New Information About Sprites." ScienceDaily. ScienceDaily, 17 October 2002. <www.sciencedaily.com/releases/2002/10/021016075852.htm>.
University Of Houston. (2002, October 17). New Thinking Needed On Atmospheric Physics, Study Suggests; Balloon Experiments Reveal New Information About Sprites. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2002/10/021016075852.htm
University Of Houston. "New Thinking Needed On Atmospheric Physics, Study Suggests; Balloon Experiments Reveal New Information About Sprites." ScienceDaily. www.sciencedaily.com/releases/2002/10/021016075852.htm (accessed October 20, 2014).

Share This



More Earth & Climate News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Powerful Hurricane Gonzalo Heads to Bermuda

Raw: Powerful Hurricane Gonzalo Heads to Bermuda

AP (Oct. 17, 2014) Hurricane Gonzalo pounded Bermuda with wind and heavy surf on Friday, bearing down on the tiny British territory as a powerful Category 3 storm that could raise coastal seas as much as 10 feet. (Oct. 17) Video provided by AP
Powered by NewsLook.com
So, Kangaroos Didn't Always Hop

So, Kangaroos Didn't Always Hop

Newsy (Oct. 16, 2014) Researchers believe an extinct kangaroo species weighed 500 pounds or more and couldn't hop. Video provided by Newsy
Powered by NewsLook.com
Hurricane Gonzalo Is A Category 4 And Heading To Bermuda

Hurricane Gonzalo Is A Category 4 And Heading To Bermuda

Newsy (Oct. 16, 2014) Powerful hurricane could hit Bermuda this weekend, and even if it misses it will likely do some damage. Video provided by Newsy
Powered by NewsLook.com
The Largest Volcano In Centuries Is Spewing Toxic Gas

The Largest Volcano In Centuries Is Spewing Toxic Gas

Newsy (Oct. 16, 2014) One of the largest volcanic eruptions in centuries is occurring on Iceland. The volcano Bardarbunga is producing high levels of sulfur dioxide. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins