Largest High-Tech Tornado Chase Set To Begin

coondoggie writes "Next month, with the help of a variety of high-tech gear, researchers will begin a wide-ranging project to better understand the origin, structure and evolution of tornadoes. The National Science Foundation has given $9.1 million to the project called Vortex2 (of course it has a convoluted backronym), which will take place from May 10-June 13. Researchers say Vortex2 is the largest attempt in history to study tornadoes, and will involve more than 50 scientists, 40 research vehicles, and 10 mobile radars, and will cover 900 square miles in southern South Dakota, western Iowa, eastern Colorado, Nebraska, Kansas, the Texas panhandle, and western Oklahoma."

Re:Dorthy?

[Anonymous Coward]

old movie reference, "Twister", to a device used to study a tornado.

Re:Dorthy?

[snowraver1]

Dorthy was the name of the contraption that they wanted to get up into the tornato in the movie "Twister". It looked like the cylinder shaped Coke Ice-coolers that you can find near the cash register, except it was all silver colored, and filled with many small cubes (or spheres, can't recall) that would transmit data when the whole thing got picked up and started swirling around...

Tornado Evolution

[__aapmis4709]

The purpose of VORTEX2, as some comments have questioned, is to test some theories about the evolution of tornadoes in thunderstorms and why some supercells produce tornadoes while others do not. In a very simplistic explanation of what's going on, vorticity about a horizontal axis is tilted to where vortex lines intersect the ground, thus tilting the rotation into the vertical and transferring the rotation to the surface. Part of the tilting is done by the rear flank downdraft, and part of the tilting is done by the updraft. However, if the rear flank downdraft is too cold, the updraft cannot lift the air in the downdraft too much, and the rotation isn't tilted into the vertical. Present theories suggest that warmer rear flank downdrafts favor tornadogenesis. Here's a link [psu.edu] to a presentation by Dr. Markowski of Penn State about the current theory regarding tornadogenesis. VORTEX2 is an attempt to gather high resolution data sets for many supercells to test the current theory. Obviously there's much more to VORTEX2, including the testing of unmanned aircraft in storm environments. But one major objective is to test the current theory regarding tornadogenesis.

Re:900 square miles?

[__aapmis4709]

The primary domain of VORTEX2 includes much of several states, and the 900 square miles is clearly a typo. Also, VORTEX2 isn't limited to that domain. If there's tornadic thunderstorms outside of the domain and no good setups within the domain, VORTEX2 could deploy outside of the domain. The primary considerations were the road networks and the lack of trees making observations easier. Areas such as the sandhills of Nebraska are outside of the domain and the road network is limited, but if that's the only thing to chase on the Plains, VORTEX could deploy there. The preferred domain is in western Oklahoma because of the observations available (CASA radars, the OK Mesonet, etc...). But VORTEX2 isn't limited to that region.

Tornado 101 for those unfamiliar

[onyxruby]

Tornado 101 for those who are curious, since this always comes up if I travel overseas.

1. Are tornadoes really that dangerous?
Yes that can be very dangerous, capable of rendering concrete building to rubble in seconds. They can rip interstate freeways out of the ground and have been recorded of 1.5 km in size (the small fast moving ones are arguably more dangerous). However they tend to very erratic, they can destroy one house, leave the next door house intact and destroy the one after that. By and large they don't kill huge numbers of people, but they do a lot of damage.

2. Why don't people live away from where tornadoes exist?
Because tornado alley is quite large, much bigger in size than the UK, arguably around Germany in size or larger (depending on how you measure tornado alley). Since your chance of encountering a tornado at your home in any given year is pretty small, people tend to view them about like they do the chances of being struck by lightning. Why abandon the midsection of the country on an oddball chance?

3. Are tornadoes all that dangerous?
Nope, most are small in size and many never even touch down. It's a rare tornado that destroys entire towns.

4. Can they occur at night?
Yup, they definitely can occur at night, (I've encountered one at night and it was pretty freaky).

I'm not a meteorologist or anything, I've just lived through a few and know these questions seem to pop up...

Kansas Storm Chasing

[CompMD]

I certainly hope to run into these fine people on the highway. Too bad they probably are going to stay really far west. I'm equipped with 40 mile radar, satellite weather imagery, and a very fast station wagon it all goes in.

Re:Use a tank

[__aapmis4709]

As another comment has pointed out, the TIV is exactly such a vehicle. The purpose of the vehicle is to attempt to get good observations of near-surface winds in a tornadic vortex. Mobile radars have done a good job of measuring winds at heights of 75 or 100 meters above the surface. But the question is how strong are the winds near the surface where they actually have the potential to do damage.

In addition to the TIV and the DOW (Doppler On Wheels), pods with instruments are also deployed to take observations.

I'm not aware that the TIV will be involved in VORTEX2. However, there will be plenty of mobile radars, including Josh Wurman's DOWs. The pods will also be deployed.

Texas Tech has developed instruments that are referred to as the sticknet, also for taking observations. These are designed to withstand strong winds and remain fastened into the ground.

Another new technology that will be used during some events in VORTEX2 is unmanned aircraft systems. VORTEX2 is one opportunity to demonstrate the usefulness of unmanned aircraft systems in taking observations. And one goal is to get an unmanned aircraft into the rear flank downdraft of a supercell. That's not in the tornado, but it's pretty close.

Re:Dorthy?

[__aapmis4709]

Right now, tornado (and severe thunderstorm) warnings are issued when one of two things happens:

1) A tornado or a funnel cloud is spotted
2) Doppler radar indicates strong rotation and the forecaster believes a tornado is possible or likely

It's always better to detect the tornado vortex signature on radar before a tornado actually develops. There is some lead time, should a tornado actually develop, and people have time to take cover. But the bottom line is that we still warn based on observations, not on a forecast.

A fundamental reason for conducting VORTEX2 is to investigate tornado formation to understand why some supercell thunderstorms are tornadic while others are not. One reason that has been suggested is that warmer rear flank downdrafts are more favorable than colder rear flank downdrafts for tornadogenesis. Physical reasons for this have been proposed, but at this time it still remains untested.

It is hoped that by investigating the storm environment, there will be a better understanding of why some supercell thunderstorms are tornadic while others are not. If the properties of the rear flank downdraft influence the tornado potential, those observations of wind speed, temperature, moisture, and pressure are important. The purpose of understanding why some supercells are tornadic while others are not isn't just for meteorologists to publish papers in journals and get NSF funding. The purpose is to better understand tornado formation in hopes that in the future, tornado warnings are based on forecast tornado potential instead of observing the rotation. If forecasters can predict when tornadic rotation will develop in storms, it will increase the lead time on warnings. It will give people valuable time to alert others of approaching dangerous weather and to take cover.