Check out this animation below:
Mike Eilts is the Chief Executive Officer and president of Weather Decision Technologies (WDT), the parent company of RadarScope, which offers the popular professional weather radar app for smartphones.
It is no surprise that Eilts was checking the radar — but what he found is a bit of a surprise.
First, a little bit of radar analysis background: In viewing the animation above, take note at what is happening. The early morning “ground clutter” nearly goes to zero, which indicates that the ground is warming due to sunrise, and the thermal inversion is almost gone. In the final frames, the radar “flares up” again, indicating the birds taking flight.
Accompanying the video on his Facebook page, Eilts wrote, “Earthquake! Video […] shows radar during earthquake, the large growth in echoes is birds taking off. Interesting things you can see on radar! What is interesting to me is that it appears that birds starting flying about 6:47, yet the 5.6 earthquake occurred at 7:03, what do they know that we do not know? #earthquake #RadarScope“
Though the radar imagery is focused on Oklahoma City, the earthquake referenced in Eilts’ post occurred in the city of Pawnee, located approximately 93 miles northeast of Oklahoma City and 55 miles northwest of Tulsa.
OK earthquake was rated a 5.6 magnitude, centered 14 km NW of Pawnee, OK, depth 6.6 km at 7:02 am. #okwx #arwx #earthquake
— NWS Tulsa (@NWStulsa) September 3, 2016
(MORE: Earthquake shakes Oklahoma Saturday morning)
Birds and other migratory animals are frequently detected on radar imagery, usually as an ever expanding “ring” during a radar loop.
Purple martins are leaving the roosts this morning, as indicated by the green rings on #ValleyWx radar #ALwx @TNwx pic.twitter.com/ZLhIWBS5C1
— Christina Edwards (@ChristinaWHNTwx) August 6, 2016
(MORE: ‘Bird rings’ detected on weather radar)
However, Eilts makes an interesting point: According to the radar, the birds dispersed approximately 15 minutes before the earthquake took place.
The U.S. Geological Survey states that the earliest record of animals fleeing before an earthquake is from Greece in 373 B.C., but it also notes that the majority of information regarding animal migration prior to earthquakes is inconsistent and anecdotal, requiring additional scientific research.