Featured Research

from universities, journals, and other organizations

Satellites give an eagle eye on thunderstorms

Date:
December 20, 2010
Source:
University of Wisconsin-Madison
Summary:
It's one of the more frustrating parts of summer. You check the weather forecast, see nothing dramatic, and go hiking or biking. Then, four hours later, a thunderstorm appears out of nowhere and ruins your afternoon. Additional data, taken from a satellite, could greatly improve the accuracy of thunderstorm prediction a few hours out.

It's one of the more frustrating parts of summer. You check the weather forecast, see nothing dramatic, and go hiking or biking. Then, four hours later, a thunderstorm appears out of nowhere and ruins your afternoon.

Related Articles


Thunderstorms can bring intense rain, hail, lightning and even tornadoes, but "predicting them a few hours out is one of the great problems of meteorology," says Chian-Yi Liu, a postdoctoral researcher at the University of Wisconsin-Madison.

And the consequences can be more serious than a rained-out hike -- even major storms can be missed, Liu says, including the one that dumped up to 10 inches of rain on La Crosse, Wis., on Aug. 18, 2007. "Predictions for the day said a moderate chance of thunderstorms," Liu says, "but this one produced an inch or two of rain per hour and caused severe flooding."

Thunderstorms are called "convective storms" because they are powered by differences in air density that cause updrafts and cooling, and can lead to hail, rain, tornadoes and lightning.

In a presentation at the meeting of the American Geophysical Union in San Francisco on Dec. 16, Liu will show that additional data, taken from a satellite, could greatly improve the accuracy of thunderstorm prediction a few hours out.

Liu works at the Cooperative Institute of Meteorological Satellite Studies (CIMSS) at UW-Madison, which both processes satellite data and explores how meteorologists can use more effectively.

"Scientists understand the basic causes of thunderstorm formation," Liu says, "but their major source of data is usually surface observations, or measurements taken from balloons that are released into the lower atmosphere, and they usually lack information about the upper atmosphere."

When Liu and his colleagues introduced data on conditions at 15,000-32,000 feet of altitude into the equation, they found a considerable improvement in the crucial three- to six-hour forecast. The data was collected from 400 different events by sensors on NASA's Aqua satellite that measure conditions at different altitudes.

Convective storms allow the atmosphere to dump excess energy, held in the form of heat and humidity, and release it as wind and especially precipitation. Convection storms are most likely when the atmosphere is unstable, Liu says. "Our analysis shows that if there is instability at around 30,000 feet, with other storm-favorable conditions, a convective storm will develop in the following three to five hours. Using the top-down view of a satellite reverses our usual way of thinking about convective storms, and may suggest an explanation for storms that arise when they would not be predicted using conventional methods."

"For a long time, we have looked at convection and instability from a near-surface perspective," says co-author Steve Ackerman, a professor of meteorology and director of CIMSS. "What Chian-Yi has showed is that this is not always the case, you can drive instability from upper troposphere too."

The troposphere is roughly the lower six miles of the atmosphere.

Convection releases energy and feeds on itself, Ackerman says. "If you have unstable conditions in the atmosphere and things get moving, they will continue to move by themselves. Our perspective has been how it could get started from the ground. Chian-Yi has shown that it can start from the top as well."

CIMSS has a good working relationship with National Weather Service, Ackerman says, and has a "proving ground" process that can quickly incorporate research results into forecast methods.

"In my experience, there are not many advances that come along with so much potential to improve forecasts," Ackerman says. "This is an advance in the science, and it takes this perspective: Let's not always look at the atmosphere from the ground. Let's also look at what happens in the upper atmosphere."


Story Source:

The above story is based on materials provided by University of Wisconsin-Madison. Note: Materials may be edited for content and length.


Cite This Page:

University of Wisconsin-Madison. "Satellites give an eagle eye on thunderstorms." ScienceDaily. ScienceDaily, 20 December 2010. <www.sciencedaily.com/releases/2010/12/101215163754.htm>.
University of Wisconsin-Madison. (2010, December 20). Satellites give an eagle eye on thunderstorms. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/2010/12/101215163754.htm
University of Wisconsin-Madison. "Satellites give an eagle eye on thunderstorms." ScienceDaily. www.sciencedaily.com/releases/2010/12/101215163754.htm (accessed October 23, 2014).

Share This



More Earth & Climate News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

Reuters - Light News Video Online (Oct. 22, 2014) The pair of rare white northern rhinos bring hope for their species as only six remain in the world. Elly Park reports. Video provided by Reuters
Powered by NewsLook.com
Trick-or-Treating Banned Because of Polar Bears

Trick-or-Treating Banned Because of Polar Bears

Buzz60 (Oct. 21, 2014) Mother Nature is pulling a trick on the kids of Arviat, Canada. As Mara Montalbano (@maramontalbano) tells us, the effects of global warming caused the town to ban trick-or-treating this Halloween. Video provided by Buzz60
Powered by NewsLook.com
Traditional Farming Methods Gaining Ground in Mali

Traditional Farming Methods Gaining Ground in Mali

AFP (Oct. 20, 2014) He is leading a one man agricultural revolution in Mali - Oumar Diatabe uses traditional farming methods to get the most out of his land and is teaching others across the country how to do the same. Duration: 01:44 Video provided by AFP
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