Aletho News

Claims Of Increasing Tornado Outbreaks Don’t Hold Water

By Paul Homewood | Not A Lot Of People Know That | December 3, 2016

http://science.sciencemag.org/content/early/2016/11/30/science.aah7393

Who will rid me of this junk science?

The latest attempt to prove that tornadoes are becoming more extreme:

ABSTRACT

Tornadoes and severe thunderstorms kill people and damage property every year. Estimated U.S. insured losses due to severe thunderstorms in the first half of 2016 were 8.5 billion USD. The largest U.S. impacts of tornadoes result from tornado outbreaks, which are sequences of tornadoes that occur in close succession. Here, using extreme value analysis, we find that the frequency of U.S. outbreaks with many tornadoes is increasing and is increasing faster for more extreme outbreaks. We model this behavior by extreme value distributions with parameters that are linear functions of time or of some indicators of multidecadal climatic variability. Extreme meteorological environments associated with severe thunderstorms show consistent upward trends, but the trends do not resemble those currently expected to result from global warming.

http://science.sciencemag.org/content/early/2016/11/30/science.aah7393

As any proper expert on tornadoes knows, many more tornadoes get to be reported nowadays, simply because of changes in reporting procedures.

McCarthy & Schaefer explained this fully in their paper, TORNADO TRENDS OVER THE PAST THIRTY YEARS, which they wrote in 2003:

This paper looks at the reported frequencies of tornadoes and their characteristics over the contiguous United States since 1970. There was a significant increase in tornado occurrence during two periods in the last 33 years – in the early 1980s when National Weather Service (NWS) warning verification began, and in 1990 when the WSR-88D [Dopppler] became operational…..

The years 1950-1969 were a growth period because it was the start of the public awareness and communication revolution that gave tornadoes increased publicity due to television news coverage and graphic depictions of tornadoes and tornado damage….

The increase in reported tornado frequency during the early 1990s corresponds to the operational implementation of Doppler weather radars. Other non-meteorological factors that must be considered when looking at the increase in reported tornado frequency over the past 33 years are the advent of cellular telephones; the development of spotter networks by NWS offices, local emergency management officials, and local media; and population shifts…..

The growing “hobby” of tornado chasing has also contributed to the increasing number of reported tornadoes. The capability to easily photograph tornadoes with digital photography, camcorders, and even cell phone cameras not only provides documentation of many weak tornadoes, but also, on occasion, shows the presence of multiple tornadoes immediately adjacent to each other.

www.spc.noaa.gov/publications/mccarthy/tor30yrs.pdf

When these weaker tornadoes are stripped out, it is clear that there is a declining trend of stronger tornadoes.

https://www.ncdc.noaa.gov/climate-information/extreme-events/us-tornado-climatology/trends

This Tippett paper defines a tornado outbreak as one containing at least six tornadoes. But given that more tornadoes are now reported than in earlier decades, it is inevitable that more such outbreaks are now being recorded, and that they will tend to have a higher number on average.

Indeed, McCarthy’s comment “shows the presence of multiple tornadoes immediately adjacent to each other”, is particularly relevant. Prior to the use of mobile phones and Doppler, many of these would have simply been lumped together as just one big tornado.

This paper seems to be a classic case of a team of scientists, who appear to have little knowledge of the subject, using computer models to arrive at a preordained conclusion.

December 3, 2016 - Posted by aletho | Deception, Fake News, Mainstream Media, Warmongering, Science and Pseudo-Science