Most of us are aware of the effect of physical geography on our lives to some extent. We know the difference between a hill and a valley, and have some awareness of the hazards that result from living on a flood plain in times of trouble. We may be able to see the effects of rain shadows in high deserts or the swampiness that results from poor drainage. We may speculate on the effects of a navigable rivers on the prosperity of some parts of the world or comment on the similarities of the fate of hill peoples across a wide part of the world. In all of these cases, we may look at the lie of the land and see how it affects the life of people by providing the constraints under which they operate. And if these constraints may be overcome, they are a reality that must be addressed.
Bathymetry is far less familiar to us than geography, for the obvious reason that the terrain of the earth is its surface, but the terrain of the ocean floor is beneath the surface. I became aware myself of the importance of bathymetry when I worked for several months as an undergraduate research assistant at the Tsunami Research Lab and struggled with lab data that showed the difference in wave run-up based on the bathymetry of the simulated harbor. The differences could be very dramatic. I noted, for example, that the historical dangers of tsunamis for Crescent City, California were in large part due to the particular features of the undersea terrain around this city, which could make any tsunami a particularly threatening one.
As human beings we are generally poorly aware of bathymetry except when it forcibly intrudes into our lives. Deep trenches, for example, are a sign of the the subduction of ocean plates underneath neighboring bodies of land, and present a sign of great risks for major earthquake activity. These deep trenches can be found in many places around the earth under the sea, but most of the time little attention is paid to them until the moment when a major earthquake occurs and someone comments briefly on the specific plates where these trenches occur, especially if they are close to a major metropolitan area. Whether we are dealing with earthquakes or tsunamis, often our lives are shaped (even dramatically) by what is beneath the surface and what cannot be seen unaided as we look on the apparently tranquil or rhythmic appearance of the surface of the ocean.
Issues of bathymetry are often involved in more than simply natural disasters as well. The question of the terrain of the undersea can influence questions of how desirable and wealthy in natural resources a particular area of the sea may be for the land powers who control it. Whether we are talking about barrier reefs or undersea oil rights or even the possibility of gold and other precious metals (if a cost-effective way can eventually be found of mining them from the sea), the terrain of the ocean plays a major role in determining the natural wealth that nations may enjoy, at least those nations which have access to the sea. A keen attention to the terrain of the ocean can influence choices of harbors and ports as well as provide opportunities for economic development based on the specific resources available in a given sea.
For human beings, bathymetry provides us with other useful lessons that are more symbolic in nature. As beings we are not like the terrain of the land, and we are more like the terrain of the ocean. All too often the risk factors of our lives as well as our talents and gifts, are underneath the surface. At least two of the blogs I read (and comment on) often are written by young women who are intelligent and present their written thoughts well but who on the surface are extremely shy and reserved. Those who only look at the peaceful and quiet surface would be ignorant of the intellectual treasures that lie underneath the surface of those seas. I suspect their experience is not unusual. We judge others all too often on what we see, never suspecting that their character may contain unexpected depth in areas we would simply not notice because it is not superficially visible. We must be sensitive to this fact, first admitting that what we see is not reflective of reality as a whole, and then patient enough to explore those depths gradually over time as circumstances allow. For that which cannot be seen and is not recognized is still there, and still real, and potentially even more dangerous or rewarding for the fact that their reality is not seen.