Tag Archives: tornadoes

Do tornadoes form top-down or down-up?

The uncertainty of science: New data now suggests that tornadoes might form from the ground upward, not from the clouds downward, as previously and generally accepted believed.

Houser and a team of researchers from the University of Oklahoma happened to be monitoring the storm with a new type of mobile Doppler radar system that collected tornado wind speeds every 30 seconds. Afterwards, Anton Seimon, a geographer at Appalachian State University in Boone, North Carolina who had chased the El Reno storm, collected hundreds of still photos and videos of the epic twister from citizens and fellow storm chasers.

When Houser compared her radar data with images collected by Seimon, she noticed something odd. The images clearly showed a visible tornado at the ground several minutes before her radar picked it up. Puzzled, Houser went back through her radar data and analyzed the data taken at the ground. It is typically difficult to get good radar measurements at or near the ground, but Houser and her team had deployed their instrument on a slight rise and there were no obstructions between them and the tornado, so this time, they had data good enough to work with.

She found clear evidence of rotation at the ground before there was rotation at higher altitudes. Houser then examined other sets of tornado data and found that in many cases, tornado-strength rotation develops at or near the ground first, rather than starting in the cloud itself. In all four datasets she analyzed, none of the tornadoes formed following the classical “top-down” process.

What is really interesting about this research is that it shows that at least some tornadoes develop from the ground up, something no one predicted. The research also illustrates that the formation of tornadoes is very complicated and that we still do not understand it, in the slightest.

While the researchers here try to imply that this data also proves that all tornadoes must form from the ground up, they are wrong. The data shows that some appear to form from the bottom up, but this does not prove that others might do the opposite. We simply do not know enough yet.


Last three years the quietest for tornadoes ever

The uncertainty of science: 2014 caps the quietest three year period for tornadoes on record, and scientists really don’t understand why.

Harold Brooks, a meteorologist with the National Severe Storms Laboratory in Norman, Okla., said there’s no consistent reason for the three-year lull — the calmest stretch since a similar quiet period in the late 1980s — because weather patterns have varied significantly from year to year. While 2012 tornado activity was likely suppressed by the warm, dry conditions in the spring, 2013 was on the cool side for much of the prime storm season before cranking up briefly in late May, especially in Oklahoma, SPC meteorologist Greg Carbin said. Then, activity quickly quieted for the summer of 2013.

Global warming activists had confidently predicted that, because of global warming, we were about to see killer tornadoes of unprecedented frequency. Well, not only has the climate not warmed these past 18 years, we are seeing fewer extreme weather events.


The high peak in tornado in 2011, the most in fifty years, was quickly attributed to global warming. Eric Berger asks: How does this explain this year’s low number, the fewest in fifty years?

The uncertainty of science: The high peak in tornado in 2011, the most in fifty years, was quickly attributed to global warming. Eric Berger asks: How does this explain this year’s low number, the fewest in fifty years?

If you click on the first link, you will see that the global warming scientists quoted, Kevin Trenberth, Michael Mann, and Gavin Schmidt, were all involved in the climategate emails, where they came off very badly. Moreover, there have been significant questions about the work of Michael Mann himself. I also wonder if these guys will have anything to say about the dearth of tornadoes today.