What causes tornadoes to form?

siberiaskeinData Management

Nov 20, 2013 (3 years and 11 months ago)

243 views

What causes tornadoes to form?

Co
-
funded by NSF
0755462 and NSF
0746816 and its REU supplement
1036023

Data generated using TeraGrid resources: kraken and nautilus at NICS from the University of
Tennessee


Outcome

REU students working in collaboration with scientists at the National
Severe Storm
Laboratory have developed a series of high resolution simulations of supercell
thunderstorms that will enable us to study the formation of tornadoes.

Impact/Benefits

Tornado
es are one of the most violent forms of hazardous weather, causing millions
of dollars of damage and loss of life and property every year. In 2008, tornadoes
caused
126 deaths in the United States.


Background/Explanation

While improvement in radar capabi
lities and in prediction techniques have
dramatically improved the ability to predict tornadoes, the false alarm

rate remains
unacceptably high.
In order to improve the prediction of tornadoes, we need to
dramatically improve our understanding of how they

form.

We are
developing
novel spatiotemporal data mining models that will enable us to revolutionize our
understanding of the formation of tornadoes.

Because tornadoes are a rare event in nature, we are
creating
an unprecedented set
of simulations.
Th
ese simulations are high resolution, enabling us
resolve

tornadic
vortices.
By studying simulated data, we gain a complete picture of the fundamental
meteorological variables surrounding the tornadoes.
This unique dataset will
enable us to study the form
ation of severe storms,

both tornadic and non
-
tornadic.
We are developing and applying
our
spatiotemporal data mining models to this data.

These simulations and analysis are made possible through the supercomputing
resources from TeraGrid, specifically
the machines at the University of Tennessee
and NICS. Without these machines, this work would not be possible as the
resources required are not available for general purchase.

Images/videos understandable by general audience, with captions and credits

Cap
tion
for

first

image below:

This graph

show
s

the reflectivity at the surface
of one of
our simulations. R
edder colors indicate a region with more intense precipitation.
This
graph also shows a
hook echo region, a region indicative of a tornado, in the so
uthw
est
quadrant of the simulation.


Caption for second image below: This graph
shows the corresponding pres
sure, wind,
and vorticity measurements

at the same time step for the same simulation

as shown
above
. The arrows show the wind field, the contour l
ines show the pressure gradients,
and the colors show the vorticity. Vorticity is a measure of the instantaneous spin.
Combined with a dramatic change in pressure, vorticity can be used to confirm the
presence of a tornado
, which is seen in the same regi
on as the hook echo in the
previous graph
.