Here is a very cool article by researchers in Australia and Norway, Long-Term Sea-Level Fluctuations Driven by Ocean Basin Dynamics. It reminds us that historical sea levels have been 170 meters higher than they are today. (By my calculation, that would make Indiana beachside property.) Of course, sea levels have also been far lower than they are today. Lots can happen in just 900 million years.
Sea level changes are part of earth’s natural rhythm as the intensity of the sun changes over time. We need to stop whining about change and learn how to deal with it. Next time people in New Jersey notice that their feet are getting wet, I suggest they move a little more to the west.
Earth’s long-term sea-level history is characterized by widespread continental flooding in the Cretaceous period (145 to 65 million years ago), followed by gradual regression of inland seas. However, published estimates of the Late Cretaceous sea-level high differ by half an order of magnitude, from 40 to 250 meters above the present level. The low estimate is based on the stratigraphy of the New Jersey margin. By assimilating marine geophysical data into reconstructions of ancient ocean basins, we model a Late Cretaceous sea level that is 170 (85 to 270) meters higher than it is today. We use a mantle convection model to suggest that New Jersey subsided by 105 to 180 meters in the past 70 million years because of North America’s westward passage over the subducted Farallon plate. This mechanism reconciles New Jersey margin–based sea-level estimates with ocean basin reconstructions.