Do The Northern Lights Really Make A Noise?
For a long time, the answer to the question ‘what causes the Northern Lights?’ didn’t have a scientific answer. Throughout the ages, different groups of people created their own theories and mythologies regarding what this mysterious light display was, from the Romans believing them to be the incarnation of the goddess of dawn to the Norsemen believing they were fearless warriors riding into battle. However, we now know that – at least in simple terms – the Northern Lights are caused by solar winds interacting with Earth’s magnetic field.
But there is one aspect of the Aurora Borealis that, until recently, was thought to be another part of folklore and an embellished tale to make the natural phenomenon seem even more alluring. Many have said that the Northern Lights often make a sound when they appear, crackling and popping overhead. These stories were regarded as tall tales by those who didn’t witness the sounds, but could it be that they were really based on fact?
Scientists in Finland have not only confirmed that there is a noise created by the Aurora, but they have also figured out why it occurs. Those who have heard the sound in the past put it down to various things, including pine needles crackling as they discharged the static electricity in the air. However, it seems that it actually involves a layer of the atmosphere that few people outside the world of science and meteorology are aware of, an inversion layer.
During warm, still days, this layer builds and forms in a region of the atmosphere where temperature increases the higher you go rather than the opposite. After the sun sets, the inversion layer creates a sort of barrier that keeps negatively and positively charged particles either side from coming into contact with each other. If the Northern Lights then appear, the barrier is broken by the geomagnetic storm and the particles mix to create a crackling sound similar to that which you hear when receiving a static shock from the car door or an escalator rail.
The scientists from Aalto University in Espoo, southern Finland, proved this by figuring out that the sounds were emanating from around 250 metres above the ground. This is roughly where a typical inversion layer usually forms and means this is a very realistic explanation.
So there you have it. Not only are the Northern Lights a feast for the eyes, they can provide quite a show for the ears too. If you would like to see, and hear, them for yourself, we have a wide range of expedition cruises available that focus on this goal. Call us today for more details or to book your polar adventure.