Scientific American is my favored bedtime reading.  The only drawback to this habit is when articles about climate change cause insomnia.  This is not an infrequent occurrence, as SA is very diligent about beating the climate change drum & I’m listening carefully.

dust storms over baja california. photo courtesy of nasa

A recent article by Jeffrey Bartholet about dust was one of these occasions. I’d read Timothy Egan’s book The Worst Hard Time & heard about the debilitating ‘haboob‘ dust storms in Arizona last summer, but the idea that dust from Africa “is responsible for 75-80% of the dust that falls over Florida” and for the “fertility of the Amazon”   was a new concept for me.

It turns out that atmospheric dust -how & where it moves from & to – is a key factor in the earth’s climate, but one that scientists are just beginning to understand.  Dust affects how clouds form, & clouds in turn affect precipitation & regulation of earth’s temperature due to their reflective properties.  Huge clouds of dust are moving around the earth all the time – one region’s desert is another’s fertile soil.  It’s not at all clear what the relationship is between periods of more or less dust and climate change.  What does seem clear, though, is that our awareness of the nature and role of airborne dust will become more important into the future.

Which brings me to a footnote about household dust mites – another cause of insomnia, but this time from the opposite end of the dust spectrum.  The results of the digestive processes of these charming creatures are a common cause of rhinitis & other allergic symptoms, of which I am a long-time sufferer.  They live in human abodes everywhere in the world, and are particularly well adapted to a meal of shed flakes of human skin. Yum.  Better get used to it…seems like we humans are in a long-term relationship with household dust mites.

So – dust.  It’s not just one of those annoying things we need to wipe off our window blinds. Like most things, its more complicated than that.  As Robert J. Swap, co-author of early thinking about African dust, noted, “We need to honor the complexity of nature.”