VORTEX projects

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NSSL mobile mesonet vehicles of the first Project VORTEX, equipped with surface measurement equipment. NSSL vehicles on Project Vortex.jpg
NSSL mobile mesonet vehicles of the first Project VORTEX, equipped with surface measurement equipment.

The Verification of the Origins of Rotation in Tornadoes Experiment (or VORTEX) are field experiments that study tornadoes. VORTEX1 was the first time scientists completely researched the entire evolution of a tornado with an array of instrumentation, enabling a greater understanding of the processes involved with tornadogenesis. A violent tornado near Union City, Oklahoma was documented in its entirety by chasers of the Tornado Intercept Project (TIP) in 1973. Their visual observations led to advancement in understanding of tornado structure and life cycles. [1]

Contents

VORTEX2 used enhanced technology that allowed scientists to improve forecasting capabilities and improve lead time on advanced warnings to residents. VORTEX2 sought to reveal how tornadoes form, how long they last and why they last that long, and what causes them to dissipate. [2]

VORTEX1 and VORTEX2 was based on the use of large fleets of instrumented vehicles that ran on land, as well as aircraft and mobile radars. Important work on developing and coordinating mobile mesonets came from these field projects. [3] [2] Analysis of data collected in subsequent years led to significant advancement in understanding of supercell and tornado morphology and dynamics. The field research phase of the VORTEX2 project concluded on July 6, 2010. [4]

VORTEX1

VORTEX1
Dimmitt Tornado1 - NOAA.jpg
Project Vortex. The Dimmitt tornado. National Severe Storms Laboratory (NSSL)
Date1994 and 1995
Location Tornado Alley
Also known asVerification of the Origins of Rotation in Tornadoes Experiment 1
OutcomeDocumented an entire tornado, which, in conjunction with deployment of the NEXRAD system, helped the National Weather Service (NWS) to provide severe weather warnings with a thirteen-minute lead time, and reduce false alarms by ten percent.
Website http://vortex2.org/
VORTEX2
Date10 May 2009 – 13 June 2009 and 1 May 2010 – 15 June 2010
Location Tornado Alley
Also known asVerification of the Origins of Rotation in Tornadoes Experiment 2
Website http://vortex2.org/
VORTEX2 field command vehicle with tornado in sight. Wyoming, LaGrange. 2009 Nssl0311 - Flickr - NOAA Photo Library.jpg
VORTEX2 field command vehicle with tornado in sight. Wyoming, LaGrange. 2009

The VORTEX1 project sought to understand how a tornado is produced by deploying tornado experts in around 18 vehicles that were equipped with customized instruments used to measure and analyze the weather around a tornado. As noted aircraft and radar resources were also deployed for such measurements. The project directors were also interested in why some supercells, or mesocyclones within such storms, produce tornadoes while others do not. It also sought to determine why some supercells form violent tornadoes versus weak tornadoes.

The original project took place in 1994 and 1995. Several smaller studies, such as SUB-VORTEX and VORTEX-99, were conducted from 1996 to 2008. [5] VORTEX1 documented the entire life cycle of a tornado, for the first time measuring it by significant instrumentation for the entire event. . [6] Severe weather warnings improved after the research collected from VORTEX1, and many believe that VORTEX1 contributed to this improvement. [7]

“An important finding from the original VORTEX experiment was that the factors responsible for causing tornadoes happen on smaller time and space scales than scientists had thought. New advances will allow for a more detailed sampling of a storm's wind, temperature, and moisture environment, and lead to a better understanding of why tornadoes form –-and how they can be more accurately predicted,” said Stephan Nelson, NSF program director for physical and dynamic meteorology. [8] [9]

VORTEX had the capability to fly Doppler weather radar above the tornado approximately every five minutes. [10]

VORTEX research helped the National Weather Service (NWS) to provide tornado warnings to residents with a lead time of 13 minutes. [11] A federal research meteorologist, Don Burgess, estimates that the "false alarms" pertaining to severe weather by the National Weather Service have declined by 10 percent. [12]

The movie Twister was at least partially inspired by the VORTEX project. [13]

VORTEX2

VORTEX2 was an expanded second VORTEX project, with field phases from 10 May until 13 June 2009 and 1 May until 15 June 2010. VORTEX2's goals were studying why some thunderstorms produce tornadoes while others do not, and learning about tornado structure, in order to make more accurate tornado forecasts and warnings with longer lead time. [14] VORTEX2 was by far the largest and most ambitious tornado study ever with over 100 scientific participants from many different universities and research laboratories.

"We still do not completely understand the processes that lead to tornado formation and shape its development. We hope that VORTEX2 will provide the data we need to learn more about the development of tornadoes and in time help forecasters give people more advance warning before a tornado strikes," said Roger Wakimoto, director of the Earth Observing Laboratory (EOL) at the National Center for Atmospheric Research (NCAR) and a principal investigator for VORTEX2. [11]

"Then you can get first responders to be better preparedpolice, fire, medical personnel, even power companies. Now, that's not even remotely possible," said Stephan P. Nelson, a program director in the atmospheric sciences division of the National Science Foundation (NSF). [10]

Joshua Wurman, president of the Center for Severe Weather Research (CSWR) in Boulder, Colorado proposes, "if we can increase that lead time from 13 minutes to half an hour, then the average person at home could do something different. Maybe they can seek a community shelter instead of just going into their bathtub. Maybe they can get their family to better safety if we can give them a longer warning and a more precise warning." [12]

VORTEX2 deployed 50 vehicles customized with mobile radar, including the Doppler On Wheels (DOW) radars, SMART radars, the NOXP radar, a fleet of instrumented vehicles, unmanned aerial vehicles (UAVs), deployable instrument arrays called Sticknet and Podnet, and mobile weather balloon launching equipment. More than 100 scientists and crew researched tornadoes and supercell thunderstorms in the "Tornado Alley" region of the United States' Great Plains between Texas and Minnesota. A number of institutions and countries were involved in the US$11.9 million project, including: the US National Oceanic and Atmospheric Administration (NOAA) and its National Weather Service and the Storm Prediction Center (SPC) therein, the Australian Bureau of Meteorology (BOM), Finland, Italy, the Netherlands, the United Kingdom, Environment Canada, and universities across the United States and elsewhere.

The project included DOW3, DOW6, DOW7, Rapid-Scan DOW, SMART-RADARs, NOXP, UMASS-X, UMASS-W, CIRPAS and TIV 2 for their mobile radar contingent. The Doppler on Wheels were supplied by the Center for Severe Weather Research, and the SMART-Radars from the University of Oklahoma (OU). The National Severe Storms Laboratory (NSSL) supplied the NOXP radar, as well as several other radar units from the University of Massachusetts Amherst, the Office of Naval Research (ONR), and Texas Tech University (TTU). NSSL and CSWR supplied mobile mesonet fleets. Mobile radiosonde launching vehicles were provided by NSSL, NCAR, and the State University of New York at Oswego (SUNY Oswego). There were quite a few other deployable state-of-the-art instrumentation, such as Sticknets from TTU, tornado PODS from CSWR, and four disdrometers from University of Colorado CU, and the University of Illinois at Urbana-Champaign (UIUC). [15] [16]

VORTEX2 technology allowed trucks with radar to be placed in and near tornadic storms and allowed continuous observations of the tornadic activity. Howard Bluestein, a meteorology professor at the University of Oklahoma said, "We will be able to distinguish between rain, hail, dust, debris, flying cows." [10]

Additionally, photogrammetry teams, damage survey teams, unmanned aircraft, and weather balloon launching vans helped to surround the tornadoes and thunderstorms. [15] [16] The equipment amassed enabled three-dimensional data sets of the storms to be collected with radars and other instruments every 75 seconds (more frequently for some individual instruments), and resolution of the tornado and tornadic storm cells as close as 200 feet (61 m). [11] [17]

Scientists met May 10 and held a class to teach the crews how to launch the tornado pods, which would have to be released within 45 seconds of notification. [18] VORTEX2 was equipped with 12 tornado PODS, instruments mounted onto 1 meter (3.3 ft) towers that measure wind velocity (i.e. speed and direction). The aim was that some of the measurements would be taken in the center of the tornado. [19] Once the pods are deployed, the teams repeat the process at the next location until finally the teams return to the south of the tornado to retrieve the pods with the recorded data. The process is repeated. This takes place within 2 miles (3.2 km), or 4 minutes away from the tornado itself. [18]

The team had 24 2 metres (6.6 ft) high portable Sticknets, which can be set up at various locations around tornado storm cells to measure wind fields, provide atmospheric readings, and record acoustically the hail and precipitation. [17] [19]

Scientists are still seeking to refine understanding of which supercell thunderstorms that form mesocyclones will eventually produce tornadoes, and by which processes, storm-scale interactions, and within which atmospheric environments. [10]

A Doppler on Wheels radar loop of the tornado intercepted on June 5. 05june-rapiddow-wide.gif
A Doppler on Wheels radar loop of the tornado intercepted on June 5.

Updates on the progress of the project were posted on the VORTEX2 home page. The scientists also started a blog of live reports. [20]

"Even though this field phase seems to be the most spectacular and seems like it's a lot of work, by far the majority of what we're doing is when we go back to our labs, when we work with each other, when we work with our students to try to figure out just what is it that we've collected," Wurman said. "It's going to take years to digest this data and to really get the benefit of this."

Penn State University featured the public release of the initial scientific findings in the fall. [12]

The forecasters were determining the best probability of sighting a tornado. As the trucks traveled to Clinton, Oklahoma from Childress, Texas, they found mammatus clouds, and lightning at sundown on May 13, 2009. [21]

The project encountered its first tornado on the afternoon of June 5 when they successfully intercepted a tornado in southern Goshen County, Wyoming, which lasted for approximately 25 minutes. One of their vehicles, Probe 1, suffered hail damage during the intercept. Later that evening, embedded Weather Channel (TWC) reporter Mike Bettes reported that elements of VORTEX2 had intercepted a second tornado in Nebraska. Placement of the armada for this tornado was nearly ideal. It was surrounded for its entire life cycle, making it the most thoroughly observed tornado in history.[ citation needed ]

Partial list of scientists and crew

VORTEX2 principal investigators plot the next step from the Field Command Vehicle (FCV). Left to right, Chris Weiss (TTU), Joshua Wurman (CSWR), Yvette Richardson (PSU), David Dowell (NCAR), Howard Bluestein (OU), and Lou Wicker (NSSL). Nssl0340 - Flickr - NOAA Photo Library.jpg
VORTEX2 principal investigators plot the next step from the Field Command Vehicle (FCV). Left to right, Chris Weiss (TTU), Joshua Wurman (CSWR), Yvette Richardson (PSU), David Dowell (NCAR), Howard Bluestein (OU), and Lou Wicker (NSSL).

The complete team comprises about 50 scientists and is supplemented by students. A complete listing of principal investigators (PIs) is at http://vortex2.org/ Archived 2019-07-31 at the Wayback Machine . An alphabetical partial listing of VORTEX2 scientists and crew:

Smaller projects

Other smaller field projects include the previously mentioned SUB-VORTEX (1997–98) and VORTEX-99 (1999), [5] [25] and VORTEX-Southeast (VORTEX-SE) (2016-2019). [26]

See also

Related Research Articles

<span class="mw-page-title-main">Tornado</span> Violently rotating column of air in contact with both the Earths surface and a cumulonimbus cloud

A tornado is a violently rotating column of air that is in contact with both the surface of the Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. It is often referred to as a twister, whirlwind or cyclone, although the word cyclone is used in meteorology to name a weather system with a low-pressure area in the center around which, from an observer looking down toward the surface of the Earth, winds blow counterclockwise in the Northern Hemisphere and clockwise in the Southern. Tornadoes come in many shapes and sizes, and they are often visible in the form of a condensation funnel originating from the base of a cumulonimbus cloud, with a cloud of rotating debris and dust beneath it. Most tornadoes have wind speeds less than 180 kilometers per hour, are about 80 meters across, and travel several kilometers before dissipating. The most extreme tornadoes can attain wind speeds of more than 480 kilometers per hour (300 mph), are more than 3 kilometers (2 mi) in diameter, and stay on the ground for more than 100 km (62 mi).

<span class="mw-page-title-main">Mesocyclone</span> Region of rotation within a powerful thunderstorm

A mesocyclone is a meso-gamma mesoscale region of rotation (vortex), typically around 2 to 6 mi in diameter, most often noticed on radar within thunderstorms. In the northern hemisphere it is usually located in the right rear flank of a supercell, or often on the eastern, or leading, flank of a high-precipitation variety of supercell. The area overlaid by a mesocyclone’s circulation may be several miles (km) wide, but substantially larger than any tornado that may develop within it, and it is within mesocyclones that intense tornadoes form.

<span class="mw-page-title-main">Tornado records</span> List of world records related to tornadoes

This article lists various tornado records. The most "extreme" tornado in recorded history was the Tri-State tornado, which spread through parts of Missouri, Illinois, and Indiana on March 18, 1925. It is considered an F5 on the Fujita Scale, holds records for longest path length at 219 miles (352 km) and longest duration at about 3+12 hours, and held the fastest forward speed for a significant tornado at 73 mph (117 km/h) anywhere on Earth until 2021. In addition, it is the deadliest single tornado in United States history with 695 fatalities. It was also the second costliest tornado in history at the time, and when costs are normalized for wealth and inflation, it still ranks third today.

The National Severe Storms Laboratory (NSSL) is a National Oceanic and Atmospheric Administration (NOAA) weather research laboratory under the Office of Oceanic and Atmospheric Research. It is one of seven NOAA Research Laboratories (RLs).

<span class="mw-page-title-main">Doppler on Wheels</span> Fleet of X-band radar trucks maintained by the Center for Severe Weather Research (CSWR)

Doppler on Wheels is a fleet of X-band and C-band mobile and quickly-deployable truck-borne radars which are the core instrumentation of the Flexible Array of Radars and Mesonets affiliated with the University of Illinois and led by Joshua Wurman, with the funding partially provided by the National Science Foundation (NSF), as part of the "Community Instruments and Facilities," (CIF) program. The DOW fleet and its associated Mobile Mesonets and deployable weather stations have been used throughout the United States since 1995, as well as occasionally in Europe and Southern America. The Doppler on Wheels network has deployed itself through hazardous and challenging weather to gather data and information that may be missed by conventional stationary radar systems.

<span class="mw-page-title-main">Joshua Wurman</span> American meteorologist

Joshua Michael Aaron Ryder Wurman is an American atmospheric scientist and inventor noted for tornado, tropical cyclone, and weather radar research, the invention of DOW and bistatic radar multiple-Doppler networks.

<span class="mw-page-title-main">Howard Bluestein</span> American research meteorologist

Howard Bruce Bluestein is a research meteorologist known for his mesoscale meteorology, severe weather, and radar research. He is a major participant in the VORTEX projects. A native of the Boston area, Dr. Bluestein received his Ph.D. in 1976 from MIT. He has been a professor of meteorology at the University of Oklahoma (OU) since 1976.

<span class="mw-page-title-main">2013 El Reno tornado</span> Widest and second-strongest tornado ever recorded

The 2013 El Reno tornado was an extremely large, powerful, and erratic tornado that occurred over rural areas of Central Oklahoma during the early evening of Friday, May 31, 2013. This rain-wrapped, multiple-vortex tornado was the widest tornado ever recorded and was part of a larger weather system that produced dozens of tornadoes over the preceding days. The tornado initially touched down at 6:03 p.m. Central Daylight Time (2303 UTC) about 8.3 miles (13.4 km) west-southwest of El Reno, rapidly growing in size and becoming more violent as it tracked through central portions of Canadian County. Remaining over mostly open terrain, the tornado did not impact many structures; however, measurements from mobile weather radars revealed extreme winds in excess of 313 mph (504 km/h) within the vortex. These are among the highest observed wind speeds on Earth, just slightly lower than the wind speeds of the 1999 Bridge Creek–Moore tornado. As it crossed U.S. 81, it had grown to a record-breaking width of 2.6 miles (4.2 km), beating the previous width record set in 2004. Turning northeastward, the tornado soon weakened. Upon crossing Interstate 40, the tornado dissipated around 6:43 p.m. CDT (2343 UTC), after tracking for 16.2 miles (26.1 km), it avoided affecting the more densely populated areas near and within the Oklahoma City metropolitan area.

<span class="mw-page-title-main">Erik N. Rasmussen</span> American meteorologist

Erik Nels Rasmussen is an American meteorologist and leading expert on mesoscale meteorology, severe convective storms, forecasting of storms, and tornadogenesis. He was the field coordinator of the first of the VORTEX projects in 1994-1995 and a lead principal investigator for VORTEX2 from 2009-2010 and VORTEX-SE from 2016-2017, as well as involved in other smaller VORTEX offshoots and many field projects.

<span class="mw-page-title-main">Paul Markowski</span> American meteorologist

Paul M. Markowski is an American meteorologist and leading expert on tornadogenesis and the forecasting of supercells and tornadoes.

The following is a glossary of tornado terms. It includes scientific as well as selected informal terminology.

<span class="mw-page-title-main">Louis Wicker</span> American meteorologist

Louis John Wicker is an American atmospheric scientist with expertise in numerical analysis, numerical simulation, and forecasts of severe convection and tornadoes. Doing storm chasing field research, Wicker deployed the TOtable Tornado Observatory (TOTO) and was in leadership roles in the VORTEX projects. He is also known for pioneering work simulating convection at the National Center for Supercomputing Applications (NCSA) at the University of Illinois at Urbana–Champaign (UIUC).

Jeffrey W. Frame is an American atmospheric scientist known for observational and modeling studies of severe convective storms and for teaching meteorology. He was a scientist for VORTEX2 and other field research programs.

<span class="mw-page-title-main">Donald W. Burgess</span> American meteorologist

Donald W. Burgess is an American meteorologist who has made important contributions to understanding of severe convective storms, particularly tornadoes, radar observations and techniques, as well as to training other meteorologists. He was a radar operator during the first organized storm chasing expeditions by the University of Oklahoma (OU) in the early 1970s and participated in both the VORTEX projects.

<span class="mw-page-title-main">Yvette Richardson</span> American meteorologist

Yvette Richardson is an American meteorologist with substantial contributions on tornado dynamics, tornadogenesis, the environments of tornadoes, supercells, and severe convection, and radar observations of these. She was a principal investigator (PI) of VORTEX2.

David C. Dowell is American atmospheric scientist recognized for research on tornado structure and dynamics and on tornadogenesis. He participated in both of the VORTEX projects.

<span class="mw-page-title-main">RaXPol</span>

The RapidX-bandPolarimetric Radar, commonly abbreviated as RaXPol, is a mobile research radar designed and operated by the University of Oklahoma, led by Howard Bluestein. RaXPol often collaborates with adjacent mobile radar projects, such as Doppler on Wheels and SMART-R. Unlike its counterparts, RaXPol typically places emphasis on temporal resolution, and as such is capable of surveilling the entire local atmosphere in three dimensions in as little as 20 seconds, or a single level in less than 3 seconds.

<span class="mw-page-title-main">Descending reflectivity core</span> Small-scale area of enhanced radar reflectivity

A descending reflectivity core (DRC), sometimes referred to as a blob, is a meteorological phenomenon observed in supercell thunderstorms, characterized by a localized, small-scale area of enhanced radar reflectivity that descends from the echo overhang into the lower levels of the storm. Typically found on the right rear flank of supercells, DRCs are significant for their potential role in the development or intensification of low-level rotation within these storms. The descent of DRCs has been associated with the formation and evolution of hook echoes, a key radar signature of supercells, suggesting a complex interplay between these cores and storm dynamics.

<span class="mw-page-title-main">Mobile radar observation of tornadoes</span>

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<span class="mw-page-title-main">Research on tornadoes in 2024</span>

During 2024, tornadoes and tornado outbreaks were extensively researched by meteorologists and engineers across the world. Some research and publications included: the effects of "Tornado Brain", the detection of tornadic infrasound, several mobile radar observations of tornadoes, including the measurement of tornadic winds over 300 mph (480 km/h), the idea of tornado alley shifting eastward, and many other things.

References

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