Another Global Warming Trend: Tornadoes in Swarms

2tornadoes

October 16, 2014
Tornado Swarms Increasing In U.S.: NOAA Study Tracks Deadly Storms

tornado-swarms1-e1413513492877-665x385“>Read more.

WASHINGTON (Reuters) – Tornadoes in the United States are increasingly coming in swarms rather than as isolated twisters, according to a study by U.S. government meteorologists published on Thursday that illustrates another trend toward extreme weather emerging in recent years.

According to a study published by government meteorologists in the journal Science on Thursday, tornadoes are increasingly coming in swarms, meaning on the days a tornado hits, it is far more likely that several more — possibly dozens — will occur that same day.

Researchers looked at tornado activity over the past 60 years and found that although the number of the deadly storms occurring each year had remained relatively steady, since the mid 1990s they have been more likely to come in swarms over fewer days per year rather than as isolated tornadoes spread throughout the season.

On the list of the 10 single days with the most tornadoes since 1954, eight have occurred since 1999, including five since 2011. That year alone had days with 115, 73, 53 and 52 twisters.

The meteorologist who led the study, Harold Brooks of the U.S. National Oceanic and Atmospheric Administration’s National Severe Storms Laboratory in Norman, Oklahoma, said emergency management agencies and insurers should be prepared to deal more often with days with lots of tornado damage.

The study analyzed the official U.S. tornado database for the six-decade period ending last year, excluding twisters below Category F1, with wind speeds of 73-112 mph (117-180 kph), on the Enhanced Fujita Tornado Intensity Scale.

Some experts have blamed weather intensity seen in recent years on global climate change they attribute to human activities. This study did not, however, offer a conclusion as to a cause.

“Knowing that the climate now has changed from that of the 1970s makes for a circumstantial argument in favor of a changing climate playing at least some role in the tornado changes,” said meteorologist Patrick Marsh of NOAA’s Storm Prediction Center.

“There are indications that heavy rainfall events are occurring with greater frequency globally, and given a warmer climate, this makes sense,” added Storm Prediction Center meteorologist Greg Carbin.

But “any trend in tornado events is much more difficult to discern,” Carbin added.

The average number of days annually with at least 20 tornadoes has more than doubled since the 1970s to upwards of five days per year in the past decade. For days with at least 30 tornadoes, there has been an average of three per year in the past decade, compared to 0.6 days per year in the 1970s.

Records for both the most and fewest tornadoes over a 12-month period have come in the past five years, with 1,050 from June 2010 to May 2011 and 236 tornadoes from May 2012 to April 2013. May is the month with the most tornado activity, followed by June and April.

Tornadoes, rapidly spinning columns of air usually spawned by rotating thunderstorms, can be among the most violent weather events. They have been reported on every continent except Antarctica but most often hit a U.S. region covering the Great Plains and parts of the Midwest and South.

Tornadoes can cause extensive loss of life and property damage like the May 2011 twister in Joplin, Missouri, that killed about 160 people and wrecked thousands of homes.

(Reporting by Will Dunham, editing by G Crosse)

Tags: ,

About Mike Neuman

Identical twin; Long-time advocate of protection of our environment; Married; Father to three sons; Grandfather to one granddaughter; Born and raised in Wisconsin; Graduate of University of Wisconsin; post graduate degrees in agricultural economics and Water Resources Management fro UWMadison; Former School Crossing Guard for City of Madison; Bike to Work for 31 years with Wisconsin Department of Natural Resources; Retired from DNR in 2007; Biked to school crossing guard site 2 X daily for 7 years retiring in 2019; in addition to being an advocate of safeguarding our environment, I am also an advocate for humane treatment of animal, children, and people in need of financial resource for humane living. I am presently a Volunteer for Habitat for Humanity, Madison, Wisconsin. I oppose all long (>500 miles) distance travel (via fossil fuel burning) for nonessential purposes and all ownership of more than one home. I am opposed to militarism in any form particularly for the purpose of monetary gain. I am a Strong believer in people everywhere having the right to speak their minds openly, without any fear of reprisal, regarding any concerns; especially against those in authority who are not acting for the public good?in a timely fashion and in all countries of the world not just the U S.. My identical twin, Pat, died in June 2009. He was fired from his job with the National Weather Service despite having a long and successful career as a flood forecaster with the Kansas City National Weather Service. He took a new position in the Midwest Regional Office in Minneapolis. Unfortunately, Pat’s work for the NWS went sour after he began to see the evidence for concern about rising global temperatures shortly after relocating to Minneapolis, and how they appeared to effect of flooding on the Red River that flows out of Canada before entering the U.S. in North Dakota. . Pat and I conversed on a regular basis with other scientists on the Yahoo Group named “Climate Concern “ and by personal email. The NWS denied his recommendation to give his public presentation o n his research at the “Minneapolis Mall of America” in February 2000, which deeply affected h,im. I will h He strongly believed the information ought be shared with the public to which I concurred. That was the beginning of the vendetta against my brother, Patrick J. Neuman, for speaking strongly of the obligations the federal government was responsible for accurately informing the citizenry. A way great similar response to my raising the issue of too many greenhouse gases being emitted by drivers of vehicles on Wisconsin highway system, my immediate supervisors directed: “that neither global warming, climate change nor the long term impacts upon the natural resources of Wisconsin from expansion of the state highway system were to be any part of my job requirements, and that I must not communicate, nor in a memorandum to all the bureau, shall any person who works in the same bureau I do communicate with me, neither verbally on the phone, by email.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: