In the United States, obesity-related health problems are soaring. The standard revolving door has gone from six to eight feet, and hauling our ampler butts costs airlines a quarter-billion more in fuel than it used to. The proportion of normal-weight Americans is at an all-time low.Ah yes, the confusion of correlation and causation. In the classic statistics text (at least for me) "How to Lie with Statistics", Darrel Huff uses the example of the correlation between the price of rum in Jamaica and preachers salaries. A pretty strong relationship with no particular causal mechanism, except both are a response to monetary inflation.
But what's a fat book got to do with the state of the Chesapeake Bay? Around the world, coastal waters have gotten fat. "Eutrophic," or overfertilized, is the technical term, from the Greek for well-fed. Dead zones like the bay's occur in more than 40 regions of the world.
It's intriguing to compare graphs tracking these declines to graphs in Messrs. Power's and Schulkin's book that track the U.S. upsurge in fatness...
Of course, the relationship between human nutrition and eutrophication in the bay is really no coincidence. The Bay is eutrophied for two related reasons. First, the number of people in the Bay watershed, spewing nutrients in sewage and in the air, and from nutrients used in agriculture.
The large number of people that the Bay supports is due to nutrients, nutrients used to raise adequate crops to feed humanity. Without added nutrients, particularly fixed nitrogen, we simply couldn't grow enough food to support all our people (or alternatively, we could convert all arable land to farmland). Look around you, who do you want to starve to death?
This is not the say that we shouldn't dispose of our wastes properly (it's practically a sin to was the fixed nitrogen in sewage by blowing it off into the air (denitrification) when it could be reused to grow more crops). And we should manage our fertilization so as to waste as little as possible by spilling it into the Bay.
But the holier than thou attitude about people and the bay is tiring. Tom, if you really feel that way, do your part to save the Bay by leaving. May I suggest North Dakota? The farmers there will really appreciate the message.