Monday, April 23, 2012

Tornado Research ~ Robin Tanamachi


Robin Tanamachi cannot remember a time when she was not fascinated by the beauty and complexity of the natural world. As a young girl, she learned she could turn to science and find answers.

Growing up in Minnesota, the varied and dynamic weather became of special interest. How could the weather change so fast in such a short amount of time? Her many questions, as well as her gift for mathematics, were strongly encouraged by her parents whom she credits with her academic and professional pursuit of tornado research.

Radar data taken in the 4 May 2007 Greensburg, Kansas tornadic supercell. The scans increase in elevation angle from top to bottom, showing that both the bounded weak echo region (BWER) and weak-echo hole (WEH) marking the tornado's location extend throughout the depth of the storm.

This was one of the first tornadoes I saw while engaged in severe weather research near Attica, KS, on 12 May 2004. The W-band radar collected vertical scans in this tornado as it passed over the road at the right side of the picture.

“Mathematics is a Swiss army knife that enables you to solve all kinds of problems, scientific and otherwise,” says Robin Tanamachi.

Photos/images provided by Robin Tanamachi.

SHAN: What attracted you to the research you are now doing?

ROBIN: I grew up in Minnesota in the 1980s, and the medium of television was influential in my choice to become a meteorologist. For two main reasons, 1986 was a particularly pivotal year:

(1) The PBS special, “NOVA: Tornado!” aired, which exposed me for the first time to tornado research and tornado scientists: Dr. Howard Bluestein (who later became my Ph.D. adviser) launching balloons into the sky, Don Burgess sitting in front of a prototype Doppler weather radar, Dr. Louis Wicker and his colleagues struggling to haul a 400-pound tornado probe out of a pickup truck with dark skies boiling overhead and lightning flashing all around.
It didn’t matter a whit to me that almost all of the scientists featured in this program were male – I wanted to do what they did. 

(2) In July 1986, a local TV station aired live news helicopter footage of a tornado damaging a Minneapolis suburb. That particular tornado had a beautiful, helical funnel. Later on, I learned that the scientists featured on the NOVA program were interested in studying the helicopter footage. The helical vortex structure had been produced in a laboratory tornado chamber, but there was some question as to whether a real tornado could ever take that shape, and the helicopter footage settled that question. The entire episode gave me a local connection to research being conducted hundreds of miles away on the Great Plains.

Severe weather researchers typically target rotating storms called supercells, like this one near Matador, TX in 2005.

The University of Massachusetts W-band radar was my primary research instrument during my graduate studies with Dr. Howard Bluestein. Here, it is scanning a small storm in the Texas panhandle.

Using dual-polarization radar technology, meteorologists can distinguish between areas of a storm where rain and hail are likely to be falling.

Without any deviation, my educational trajectory took me from that point to my current career as a radar data analyst. I feel tremendously fortunate to have lived out my childhood ambitions. (Incidentally, all three of the scientists that I named in point (1) are now my professional colleagues, and I’ve co-authored papers with two of them.)

Tornadoes, such as this one, are often spawned by supercell thunderstorms over the Great Plains of the United States.

SHAN: What are some of the improvements in the technology used for tornado research?

ROBIN: One of the greatest advancements in tornado research technology is the Doppler radar, which enables scientists to measure wind speeds inside tornadoes from a safe distance away. Placing the radar on a truck or aircraft allows us to transport the radar to the tornado, rather than waiting for the tornado to come to the radar (which it rarely does). An exciting new radar technology innovation is called dual-polarization radar, in which the pulses transmitted by the radar are prescribed either a horizontal (H) or vertical (V) polarization. Different types of particles scatter back different amounts of energy in the H and V polarizations, enabling us to differentiate between raindrops, hail stones, snowflakes, and even non-meteorological scatterers like insects, birds, dust, and debris.

The University of Massachusetts W-band radar collects vertical slices through a nontornadic supercell at sunset near Silverton, TX on 21 May 2010.

The undersides of storms are often decorated by pouch-like protuberances called mammatus clouds. When lit from the underside, they can be quite spectacular

Using dual-pol radars to study tornadoes, we have found striking signatures for tornado debris within the vortex, as well as information about raindrop and hailstone sizes and shapes. The latter information may seem less interesting, but it is crucially important for diagnosing energy transfer within a storm.

Lightning and wet roads are actually greater hazards to severe weather researchers than tornadoes.

SHAN: Why do you think there are not more women with careers in STEM (science, technology, engineering and math) areas?

ROBIN: Science can be a fiercely competitive enterprise, particularly when the funding devoted to a certain field of research is small. That competition may be a turn-off for some women. Lack of comparable female role models certainly doesn’t help, either. In the atmospheric sciences, only 12% of tenured faculty positions are occupied by women.

This radar truck has a phased array antenna instead of a traditional rotating dish. The beam is electronically rather than mechanically steered, so it can scan a volume of atmosphere up to six times faster.

Sadly, sexism is still a factor. However, that sexism is generally not the overt, “Girls aren’t good at science” sexism that we were all warned about. It manifests itself in the form of higher rejection rates for our manuscripts and proposals, greater skepticism of our findings, more frequent interruptions at meetings, and reduced recognition (pay, awards) for our efforts, among other things. It’s no wonder that female scientists come out feeling exhausted rather than accomplished. (Dr. Valerie Young enumerates many of these statistics in her book, The Secret Thoughts of Successful Women.) This type of sexism is so insidious that those effecting the sexism may not even be aware that they are doing so!

However, I am encouraged to see many talented women rising through the ranks and drawing up other young female scientists in their wake. I am also encouraged by institutional reforms that make STEM career tracks more flexible and family-friendly. These reforms will benefit both male and female scientists alike.

For more about women in science, please see the National Science Foundation link:

Shän Boggs is a writer and editor living in Los Angeles. Her interests include science, technology, the environment, health, education, multimedia, art, and gourmet cooking. She is the author of a cookbook series for people with food allergies.

1 comment:

  1. Tornado season officially begins in March and winds down in August, but the last few years there have been tornadoes reported even in December.

    This past year, for example, there were six tornadoes reported on December 11 - spawned by storms that hit four southern states: