photo: Bald Eagle Bluff/Creative Commons
Confirming and refining the situation regarding sea level rise (multi-meter by 2100 without steep emission reductions according to James Hansen, remember?): A new study in Proceedings of the National Academy of Sciences reconstructs sea level rise on the US Atlantic coast for the past 2,100 years and finds that since the 19th century rates have been higher than at any other point in that time period. What's more, they show a consistent link with changes in global temperatures. In examining the record of sea level rise for the past two millennia--this was the first continuous sea level reconstruction of the time period, it should be noted--the scientists found that sea level was relatively stable from 200 BCE to 1000 CE. From the 11th century through the 15th, sea level rose about half a millimeter annually, correlating with a period of warmer climate known as the Medieval Climate Anomaly. From then through till the late 19th century, during the cooler period known as the Little Ice Age, sea level rise halted. However, from the late 19th century, sea level rise has averaged more than two millimeters per year.
The savvier TreeHugger readers are probably wondering if there's anything new here. The newness and importance of this, as touted by the National Science Foundation's program director (NSF funded the research):
Having a detailed picture of the rates of sea level change over the past two millennia provides an important context for understanding current and potential future changes. It's especially valuable for anticipating the evolution of coastal systems, in which more than half the world's population now lives. (Science Codex)
More on Sea Level Rise
Roman Ruins Show Modern Sea Level Rise Didn't Start Until Industrial Revolution
Multi-Meter Sea Level Rise by 2100 Certain With Business-As-Usual Emissions: James Hansen