An extremely powerful EF5 tornado struck Moore, Oklahoma on Monday, May 20, 2013. The deadly tornado hit with peak winds of around 210 miles an hour, and leveled large swaths of the area, killing at least 24 people, and injuring at least another 377 others. The only reason that the numbers weren’t significantly higher is because of the prevalence of tornado shelters in the area.
The tornado was only one of many produced by a larger weather system present in the region over the past couple of days. The tornado hit the ground at right around 2:45 PM CDT, and stayed there for about 50 minutes, while carving a 17-mile path through the heavily populated area. At its peak the tornado was about 1.3 miles wide…
While tornadoes have no doubt been a feature of the Great Plains region for a very long time, there has some speculation in recent years that there has been an increase in the frequency and intensity of tornadoes there,perhaps as a result of a warming/changing climate. Is there any truth to this? Or is it just speculation?
As of right now, the evidence is somewhat inconclusive, in contrast to the strong links that have been identified between climate change and floods, droughts, and heat waves. But that’s not all of the story.
Associations between a variety of climate and environmental trends do exist. An example being that as sea surface temperatures in a region increase, so does the atmospheric moisture content; this increased atmospheric moisture then leads to an increased number and intensity of severe weather events, and with these events tornado activity.
As Dr. Kevin Trenberth, former head of the Climate Analysis Section of the National Center for Atmospheric Research, stated in an interview with Climate Progress in 2010: “There is a systematic influence on all of these weather events now-a-days because of the fact that there is this extra water vapor lurking around in the atmosphere than there used to be say 30 years ago. It’s about a 4% extra amount, it invigorates the storms, it provides plenty of moisture for these storms. It’s not the right question to ask if this storm or that storm is due to global warming, or is it natural variability. Nowadays, there’s always an element of both.”
And Munich Re, one of the biggest reinsurers in the world, in a press release, stated:
Munich Re’s natural catastrophe database, the most comprehensive of its kind in the world, shows a marked increase in the number of weather-related events. For instance, globally there has been a more than threefold increase in loss-related floods since 1980 and more than double the number of windstorm natural catastrophes, with particularly heavy losses as a result of Atlantic hurricanes.
The rise in natural catastrophe losses is primarily due to socio-economic factors. In many countries, populations are rising, and more and more people moving into exposed areas. At the same time, greater prosperity is leading to higher property values. Nevertheless, it would seem that the only plausible explanation for the rise in weather-related catastrophes is climate change. The view that weather extremes are more frequent and intense due to global warming coincides with the current state of scientific knowledge as set out in the Fourth IPCC Assessment Report.
So while it remains to be seen what the exact correlation is between tornadoes and climate change, it’s looking like it may be a good idea to prepare for more tornadoes in the future.