GabyUnderstanding Sea Level Variations
Typically, the height of land is measured in relation to sea level. For instance, the eastern peak of Mount Elbrus stands at 5,595 meters above sea level. This leads us to believe that the sea level is constant and unchanging, as it serves as our reference point. But is that really the case?
No, it’s not. Seas and oceans experience “tilts.” For example, the difference in sea level between the central part of the Baltic Sea and the Åland Islands is about 30 centimeters. At the same latitude along the Pacific coast of America, sea level is half a meter higher than on the Atlantic coast. Moving from south to north along the Atlantic coastline, one can observe a gradual increase in sea level—about 35 centimeters. Even at the exits of the Panama Canal, which is only 80 kilometers long, the average difference in sea level is around 20 centimeters.
What Causes Sea Level Inequality?
The unevenness of ocean water levels is influenced by many factors. The primary causes appear to be wind effects and temperature differences. If a layer of ocean water that is 4,000 meters thick is heated by one degree Celsius, the water level will rise by 30 centimeters. Conversely, cooling that layer by one degree will cause it to contract by 33 centimeters.
