|Sea Surface by Petr Kratochvil
Mean Sea Level is a way to express the elevation of the sea with wave motion and tide changes averaged out.
Geologic observation and artifacts narrate the story of the oceans.
Sedimentary and fossil records are often the key to estimating historic sea levels. Coral reefs are also accurate markers because they grow just below the prevailing sea level of the time.
There is sedimentary and fossil evidence that sea level was more than 21 meters (70 ft) higher 400,000 years ago than it is today:
...sedimentary and fossil evidence in the walls of a limestone quarry in Bermuda that documents a rise in sea level during an interglacial period of the Middle Pleistocene in excess of 21 meters above its current level. ~ Dramatic Rise In Sea Level And Its Broad Ramifications Uncovered
Ocean and Continents
|Western Interior Seaway
Even Castles made of sand, fall into the sea, eventually.The Western Interior Seaway was an inland sea that divided North American into two landmasses during the Mid-to-Late Cretaceous period. Vast carbonate deposits indicate the Seaway was warm and tropical.
~ Jimi Hendrix
The shallow Western Interior Seaway supported abundant marine life and early birds.
- Dramatic Rise In Sea Level And Its Broad Ramifications Uncovered. ScienceDaily, February 9, 2009.
- Exceptionally Rapid Ancient Sea Level Rise Illuminates Rate of Coming Changes. TreeHugger, June 6, 2012.
- New Study Lowers Estimate of Ancient Sea-Level Rise. ScienceDaily, March 14, 2012.
- Sea Levels Much Less Stable Than Earlier Believed, New Coral Dating Method Suggests. ScienceDaily, September 11, 2011.
- Significant Sea-Level Rise in a Two-Degree Warmer World. ScienceDaily, June 24, 2012.
- Western Interior Seaway. Wikipedia.