Tuesday, May 18, 2010

Inconvenient Truth: Sea Level Rise is Decelerating

Despite alarmist claims* to the contrary, according to both tide gauge and satellite altimetry data, the rate of sea level rise since 1900 (and over the past 6000 years according to paleologic data) has been decelerating, not accelerating. Carefully selected tide gauge data by Simon Holgate of the UK Proudman Oceanographic Laboratory is shown in his poster below, which notes that the rate of sea level rise decelerated in the second half of the 20th century (despite exponential increases in CO2 emissions):
Furthermore, the rate of sea level rise as determined by satellite altimetry (which is only available since 1992 and is calibrated to tide gauges) has also decelerated over the past 5 years from 3.2 mm/yr to only 1.5 mm/yr, about the same rate as calculated by Holgate for the period 1954-2003. Paleologic data also indicate sea level rise has greatly decelerated over the past 6000 years, and that sea levels have been rising naturally since the last ice age.
Al Gore apparently doesn't need to be concerned about his purchases of  a $4.5 million condo and $8.8 million villa, both near the Pacific ocean.

*The recent NAS letter states that man-made global warming is causing "climatic patterns to change at speeds unprecedented in modern times, including increasing rates of sea level rise and alterations in the hydrologic cycle."

1 comment:

  1. http://www.agu.org/pubs/crossref/2007/2006GL028492.shtml