Changes in weather patterns creating more severe storms

(PhysOrg.com) -- A Kansas State University climate expert attributes the increase in the number and severity of tornadoes and severe storms in 2011 to a change in weather patterns.

John Harrington Jr., professor of geography, is a synoptic climatologist who examines the factors behind distinctive . He credits the increased tornado production this year to jet stream patterns in the . The patterns have created synoptic events such as the April tornado outbreak in Alabama and recent tornado in Joplin, Mo. While these events are not unprecedented, they are significant, he said.

"To put them in all in one year, that's what has people talking about this stuff," Harrington said. "The fact that this is happening all in one year and in a relatively short time frame is unusual."

Special circumstances are necessary for the creation of in the Great Plains, Harrington said. A humid atmosphere with moisture from the Gulf of Mexico and the right jet stream pattern coupled with surface convergence help to spawn a thunderstorm. Uplift from the jet stream helps to create the towering clouds associated with severe thunderstorms. Add a wind pattern set up with air filtering into the storm from the south at low levels, from the southwest at mid-levels and the northwest at higher levels, rotation of the begins and its possible for a tornado to form.

"Unfortunately in terms of death and destruction, we've had too many of those events this year," Harrington said.

Forecasting tornadoes far ahead of time differs from the more advanced hurricane and methods. The National Weather Service's Climate Prediction Center does not predict tornadoes, rather it attempts to predict jet stream patterns a month or so in the future.

In the wintertime the jet stream tends to flow above the southern United States. It migrates northward by the summertime. The area receiving the most tornadoes tends to shift with jet stream location as well. Oklahoma usually has a higher frequency of tornadoes in April, while Kansas experiences most of its tornadoes in May, Harrington said.

Synoptic patterns are different in autumn as the jet stream migrates back south, with much drier air across much of the U.S. While this does not preclude fall tornadoes from occurring, they are rare events. Connecting the surface conditions with the jet stream flow pattern helps a weather forecaster understand the likelihood for severe storms.

"That's pretty important in terms of understanding the kind of environment that will produce the necessary thunderstorms that rotate," Harrington said.

Extreme examples of weather have not been isolated to tornadoes. Heat waves, blizzards and have been increasingly more frequent or more severe according to U.S. data, Harrington said. These changes can be attributed to changes in the climate system.

The increase in severe weather events is drawing attention, he said.

"We have these good historical precedents for specific synoptic events, but they're starting to come more frequently together. That's what is very interesting, is that this weather system seems to be getting more variable."


Explore further

Tornadoes whipped up by wind, not climate: officials

Citation: Changes in weather patterns creating more severe storms (2011, June 1) retrieved 23 October 2019 from https://phys.org/news/2011-06-weather-patterns-severe-storms.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
0 shares

Feedback to editors

User comments

Jun 01, 2011
historical precedents for specific synoptic events


Are almost certainly caused by our violently unstable Sun [1].

Cyclic changes in Earth's heat source - the Sun - induce changes in Earth's climate [2,3].

Why?

Solar wobble shifts the dense, energetic neutron star inside the Sun's diffuse, globe of waste products - the photosphere [4].

1. "Earth's Heat Source - The Sun", Energy & Environment 20, 131-144 (2009)

http://arxiv.org/pdf/0905.0704

2. "Did Quiet Sun Cause Little Ice Age After All?" Science (May 26, 2011)

news.sciencemag.org/sciencenow/2011/05/did-quiet-sun-cause-little-ice-a.html?ref=hp

3. Science: Solar Wobble/Global Cooling (31 May 2011)

www.suite101.com/...Nx6K4CXS

4."Neutron Repulsion", The APEIRON Journal, in press, 19 pages (2011)

http://arxiv.org/...2.1499v1

With kind regards,
Oliver K. Manuel
Former NASA Principal
Investigator for Apollo

Jun 01, 2011
Oliver: Thank you very much for cluttering up this post with your meaningless garbage about neutron repulsion. This is an article about severe weather. Even if your observations were correct (which no one believes), you do not show a causal relationship to severe weather. What this paper does is point out that there are unusual conditions that are being identified. This climatologist is just reporting on observations. For you to try to cram your neutron repulsion and wobbling sun into this discussion should be embarrassing for you - but I know it won't be. Please show your direct link between a wobble in the sun and increased severe weather.

Jun 01, 2011
This is an article about severe weather.


Do you think neutron stars are dead nuclear embers?

Was the pulsar in the Crab Nebula recently found to be unstable?

Do you know that waste products from the Sun totally engulf planet Earth?

Why assume that Earth's constantly changing climate and its turbulent weather are independent of the Sun?

If you have not done so, I recommend that you read Stuart Clark's book about Richard Carrington's abrupt education on the violent nature of Earth's heat source in 1859.

"The Sun Kings: The Unexpected Tragedy of Richard Carrington and the Tale of How Modern Astronomy Began" {Princeton University Press, 2007] 211 pages

That violent event in September 1859 is described in the front book flap.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more