London, ON – New research shows that dust from meteoroids entering the atmosphere may play a larger role in affecting the planet’s weather than previously thought.
In a study released in this week’s issue of the journal Nature, Peter Brown of the University of Western Ontario and member of an international research coalition which includes scientists from Australia and the US, asserts that dust particles from meteoroids are in fact larger than previously thought.
As much as 90-99% of a meteoroid disintegrates upon entry into Earth’s atmosphere, leaving behind it a trail of dust. What happens to this dust has gone relatively unstudied, with scientists assuming the meteoroids disintegrate into nanometre-sized particles that are too small to affect Earth’s climate.
By studying an asteroid descending off the coast of Antarctica in September 2004, Dr Brown and his colleagues discovered that most of the meteoroid mass disintegrated into a cloud of particles, each a few microns in size. The larger micron-sized particles are in fact big enough to significantly interact with sunlight.
The work implies that larger meteor events than the one observed over the Antarctic, which might deposit millions of tonnes of dust, could lead to substantial local and global effects to the climate through warming of the stratosphere and even influence cloud production in the lower atmosphere.
With approximately 50-60 metre-sized meteoroids hitting Earth every year, Dr Brown notes it will be important to analyze the larger regional footprints meteoroid dust leaves on our environment and weather patterns. Researchers will use data acquired from this discovery to publish future papers, including some focused on possible negative effects to the ozone layer.