Tag Archives: tornado

Weather School

Oklahoma’s weather season is here so what better time to go to weather school. The Storm Prediction Center in Norman is offering just such an opportunity.

Rich Thompson is a lead forecaster at the SPC. He hosts a weekly a series on forecasting tornados. You can attend the workshops live every Tuesday evening at 7:30 at the National Weather Service office in Norman or you can watch online right here. You can also go to this YouTube channel for more archives and other presentations.

The workshops are for anyone who wants to learn more about tornados and science behind how forecasters know where one will next appear.

 

Tail feathers Changed after Severe Storms

Researchers from the University of Oklahoma and the Sutton Avian Research Center in Bartlesville have found evidence that severe storms have caused a physical change in a population of birds.

The team studied Grasshopper Sparrows near El Reno, OK. The birds survived a massive storm in May 2013. It was a deluge that saw a 2-mile wide EF5 tornado and hailstones that were more than two inches wide. The birds they studied were born just before the storm. You can read the study here.

Jeremy Ross in the field during study.

Dr. Jeremy Ross in the field during study.

Dr. Jeremy Ross was the lead researcher. He reports they found a spike in the chemical signature of what’s called pallid bands in the tail feathers of the birds. Dr. Ross says the bands contained more of a certain type of nitrogen isotope. He says the stress of living through the storm caused muscle tissue to break down which changed the composition of the nitrogen in the blood. That change plays itself out as the feathers develop. “This may be the first example of severe thunderstorms being scientifically implicated in sublethal stress impacts on wildlife,” says Dr. Ross.

Pallid band on the tail feather of a young Grasshopper Sparrow

Pallid band on the tail feather of a young Grasshopper Sparrow. Photo courtesy: W. Alice Boyle

So why would this happen? What’s it mean? Dr. Ross says the tail is less important than the wing feathers in young birds. During high-stress events, like severe storms, food can be harder to find because the hailstones can kill either one or both parents of the fledgling or kill the insects on which they feed. When that happens the body moves blood from growing feathers that are not as important in order to protect other parts of the body that need more blood and energy.

Dr. Ross say it’s not unusual for Grasshopper Sparrows to have pallid bands but it’s normally about 2% of the population. After the El Reno storm they discovered about 44% of the population showed the pallid bands.

A detailed look at the Pallid Bands in the tail feathers of young Grasshopper Sparrows

A detailed look at the Pallid Bands in the tail feathers of young Grasshopper Sparrows. Photo courtesy: W. Alice Boyle

The study came about by accident, Dr. Ross says the team was doing other research in the area when they noticed the high rate of pallid bands in the Grasshopper Sparrows. (What a great example of how fluid science can be!!) Dr. Ross told me, “This study represents the opportune accident that scientists often don’t plan for and, therefore, don’t report. We have encouraged the scientific community to follow suit and report such findings because as a connected network we can be assured that in any given year severe weather will strike an existing field study. From such events we can gain insight into what the impacts of current severe weather patterns are now and, from this insight, we can start to predict how intensifying and expanding severe weather patterns will impact wildlife populations under a changing climate.”

Forget the Doppler, Use a Warbler

Oklahoma is right in the heart of tornado alley, of course, and doppler radar salesmen probably have a field day in the Sooner state. Well, maybe our illustrious meteorologists should add a few golden-winged warblers to their storm predicting arsenal.

A recent study published in Current Biology shows that songbirds can “hear” a storm come from miles and miles away. The study reports that golden-winged warblers left the southern part of the United States last April just before a massive tornado outbreak. The birds went to Colombia (the country, not to South Carolina), then came back to eastern Tennessee only a few days later.

Researchers believe the songbirds heard the storm’s infrasound. That’s a very low pitched sound created as the storm begins to build. According to the Newsweek article, the line of thought that birds use infrasound isn’t new. It’s believed homing pigeons used it as well. But this is the first time scientists have hardcore data backing up the claim.

Could you imagine Bob the weatherman going to the TV station’s roof to check on his golden-winged warblers instead up pulling up that fancy-schmancy Doppler radar? Yeah, me either.