Recently I was treated to a concert in my back garden by a Freddie Mercury tribute band. Despite living half a mile from the racecourse where the band was playing, I could hear every word with clarity.
For those who lived closer to the venue the concert was not as loud. The sounds they received were muffled by obstacles such as buildings and trees between them and the racecourse. But the guitar riffs that arrived in my garden had travelled an indirect route, bouncing off a layer in the upper atmosphere and maintaining more of their original oomph.
It’s a well-known phenomenon, and a nuisance for many, but now meteorologists are using it to better understand the elusive winds in the second layer of Earth’s atmosphere – the stratosphere.
Javier Amezcua, a meteorologist at Reading University, has been measuring the sounds from controlled explosions and deducing the pattern of upper-level crosswinds by calculating the amount the sound is blown off-course.
These winds are difficult to measure but play a big role in the weather, sometimes enabling polar air to seep to mid-latitudes, bringing severe winter weather to North America and Europe.
