Tuesday, October 25, 2011

Is something wrong with tornado warnings?

In the wake of this year's massive April tornado outbreaks and the 22 May Joplin tornado, there's been a lot of talk about changing the National Weather Service (NWS) tornado warning process.  I don't know the inside scoop on what is being considered by the NWS, but there certainly has been a lot of media attention on the topic and it's my understanding that NWS is indeed considering changes.  I see all of this as an inappropriate reaction to the large fatality toll this year.  In some ways it's good to review the system and at least discuss whether change is necessary after a tragedy like this year, when so many lives were lost.  But hastily-constructed change is not an appropriate answer to what happened in the spring of 2011.

The public should understand that the NWS system evolved over decades as a series of more or less ad hoc decisions made in a cloud of ignorance.  If one were to ask today if the existing system is the best of all possible systems, I believe the answer would be a resounding "NO!"  The NWS warning system was not constructed after careful study of what is best to do and how best to do those things. It was built on the fly, as it were.  Nevertheless, there can be no doubt that it's worked effectively over the years to produce a much-reduced fatality toll from tornadoes compared to those in the 1920s and before.  If we change the way NWS warnings work, we should be careful not to to do so in haste under political or media pressure.  Otherwise we run the risk of screwing up a system that has worked to save thousands of lives over the years.

This is not the place for a discussion of what's wrong with the NWS warnings - that's a topic far too complex to be dealt with properly in a blog.  What I want to do here is to point out something I've been saying for a long time.  If people in the tornado-prone areas of the country choose not to take warnings seriously, is this because of failures in the warning system?  I find it to be extremely difficult to understand how people could not take a tornado warning seriously!!  Nevertheless, it seems that this is not uncommon.

Consider the tale of three tornadoes - two in 1990 and one in 2011 ... the F5 tornado that hit Hesston, Kansas,  the F5 tornado that hit Plainfield, Illinois, and the EF5 tornado that hit Joplin, Missouri.  In the Hesston event, tornado warnings were issued and people apparently took them seriously - only one life was lost.  In the Plainfield event, tornado warnings were not issued before the tornado, with 29 lives lost as a consequence.  For the Joplin event, warnings were issued about 20 min ahead of the tornado and the current figure I have for fatalities is 159 - the most from a single tornado since 1947.

Not all NWS offices do an equally good job with tornado warnings.  After the Plainfield event, for instance, a disaster survey team found many problems with the performance of the Chicago office.   Having an F5 tornado strike with no warning remains possible, but is much less likely today than it was in 1990.   The Springfield office that issued the warnings for the Joplin event did a decent job with a challenging situation, although they may have had a history of many false alarm warnings. Some of us have been saying for quite some time that large fatality counts are not necessarily a thing only of the past, and 2011 has shown those dire predictions to be true.  We have been lucky for decades and in 2011, our luck simply ran out.  It will do so again, in the future.

The sad, and seemingly inescapable conclusion I draw from this trio of major tornado events is that people in the tornado-prone parts of the USA need to understand the true risks from tornadoes.  They don't need to live their lives in constant fear - far from it.  The NWS offers state-of-the-art information about the threat of tornadoes and all people need to do is take it seriously enough to take actions to protect themselves.  Why is this so difficult?  Is it a matter of public education?  I think that might well be an important factor, but not the only one. 

There's been a lot of talk about too many false alarms from the NWS.  While I agree the NWS warning performance is not perfect and not even as good as it could be, there inevitably will be uncertainty implied (if not stated explicitly!) in their forecast and warning products.  People need to understand and accept that principle.  The public must accept their share of responsibility for what happens when tornadoes strike, rather than placing the whole burden onto the NWS to provide some product for which the science of meteorology offers little hope of being an improvement over the existing system.  Learning about the simple and inexpensive things anyone can do to protect themselves from natural hazards seems like common sense to me, not something too challenging for "the public" to do.

1 comment:

Dave Brown said...

In my opinion, life is risky from the moment of conception to death. Everything about living involves unknowns and surprises. Without accepting the risks of living and learning how to handle the risks, our species would not have advanced very far.

Weather forecasting agencies issue watches and warnings for a variety of dangerous weather events. The practice is not without its flaws and shortcomings, but under most circumstances the majority of warnings can pass the "smell test".

Improvements in preparing and delivering warnings will come with time. Until that happens, there are many existing communications vehicles through which warnings are made public. It becomes the sole responsibility of every individual to mitigate risks to life and property by being prepared for dangerous weather events and ensuring an up-to-date awareness of imminent severe weather.

For all of us, life is a minute-by-minute deal we have to live with. If minutes are important then by all means be prepared to act on a minute's notice whenever threats develop.

In this day and age of enlightenment, everyone should know the natural risks that are part of their local environment. If tornadoes, hurricanes, earthquakes, avalanches, forest fires, dangerous diseases or threats from wild animals are within the realm of possibility, then taking personal responsibility to act quickly to save life and limb should be part of daily living.

Everyone needs to be able to deal with risky events in a well rehearsed, disciplined, coordinated manner to mitigate as many nasty consequences as possible.

Is something wrong with tornado warnings? Only that they are not yet perfect. Dealing with imperfection means being prepared to the best of one's ability.

If a person is unprepared or chooses to remain uninformed of these eventualities then that individual has not accepted full responsibility for his life.

Dave Brown