CLIMATE AND CIRCULATION 
by 
Dr. William C. Boicourt 
Horn Point Environmental Laboratories 
Dr. Boicourt: I'm to address the climate and circulation 
of the Chesapeake Bay. Given the brief time, I'd like to 
consider climate in a narrow sense — the interannual 
variability. In order to cover the other aspects of climate, I 
am going to take a certain amount of professorial license and 
assign reading in the 1941 Yearbook of Agriculture entitled 
"Climate and Man." 
I want to quickly convey how the Chesapeake Bay moves, how 
we're doing as scientists in providing a description of the 
Chesapeake Bay circulation, and how we can use this under¬ 
standing to try to reduce the uncertainty in assessing the 
long-term trends in the health of Chesapeake Bay. 
The Chesapeake Bay is the archetypical estuary for physical 
oceanographers. It dominates the physical oceanographic litera¬ 
ture to the point where my colleagues in Europe bridle at the 
fact that they have to either come here and work on the Bay or 
at least compare their small, unimportant estuaries to the circu 
lation of Chesapeake Bay. To be fair, some of my colleagues 
from across the water have come to the Bay and have done rather 
well in providing new insight into estuarine circulation. 
For a description of the circulation (which most of you know 
well), we describe a simple experiment: 
Here we have a basin. On the left-hand side is freshwater, 
on the right-side is saltwater, and there is a partition separat 
ing the two. To put this experiment in perspective, I should 
explain that even physical oceanographers perform it. I used to 
consort with a bunch of decidely elitist oceanographers who 
described themselves as geophysical fluid dynamicists at an 
institution up in Massachusetts that goes down to the bottom of 
the ocean to find Titanics. They conducted this experiment in a 
rather different manner — the basin was a gin bottle and the 
two fluids were ethanol and paint thinner. The results are 
basically the same, and provide more insight than you might 
expect at first. Your intuition says that saltwater is heavier 
than freshwater. 
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