When the English poet Samuel Taylor Coleridge penned the line, Water, water everywhere not any drop to drink in the Rime of the Ancient Mariner, in 1798, water’s prevalence on this earth might have reached its apex.  Barely three hundred years had passed since Columbus demonstrated that the earth was much larger, rounder, and full of ocean than anyone thought, while a mere two hundred years later we were already feeling the pinch of our most precious resource.

This spring I am attending a most incredible series of lectures, Northeastern University’s Open Classroom series.  This semester’s theme is Climate Change. Challenges. Solutions.  Every Wednesday evening two or three speakers tackle topics such as mitigation, efficiency, fossil fuels, emerging energy options, and national security.  Yet every topic cycles back to water; our most predictable barometer of climate change. Our oceans are getting warmer, our storms are getting more violent, our sea levels are rising.  Water is essential to our existence here on earth, but it is getting less benevolent all the time.

Every Open Classroom speaker sheds new perspective on the climate issue.  But the single image that conveyed a whole new perspective to me was this diagram of the earth, presented by David Titley, Retired Rear Admiral, US Navy that annihilates the idea that we have water, water everywhere.  When we say that the earth is three-quarters water what we really mean is that we have relatively shallow puddles covering three-quarters of our surface.  But gather that water in one place, make it a single drop, and all the earth’s water creates an 800 mile diameter sphere; one thousand times smaller than the volume of the 8,000 diameter earth itself. Since the potable water on earth is less than 1% of what is available, all the drinkable water on the entire planet would fill an eight mile diameter sphere; the distance I ride my bicycle from my West Cambridge house to my Fort Point Channel workplace each day.

This is but one example of the insightful ways climate change is being presented in Northeastern’s series.  Classes end on April 17, but all the lectures are available online at http://www.northeastern.edu/policyschool/lectures-and-seminars/open-classroom/video-recordings.

Our world is more complex than that of the ancient mariner.  Water is expanding, yet it is hardly everywhere. Still, there is but a tiny drop to drink.

.