Measured sea level rise drops 30% with “pause” greater than half of RSS measurement period.
Guest essay by Larry Hamlin
A paper titled “The rate of sea-level rise” published in Nature Climate Change on March 23 by Cazenave, et al. shows that during the last decade the rate of sea level rise has declined by about 30% during the period 2003 through 2011 to about 2.4 mm/year from the rate of 3.4 mm/year in the period 1992 through 2002. The paper argues that this decrease is the result of short-term natural climate variability which it attempts to remove to reveal the “true” global warming signal with the end result being to “adjust” the lower measured sea level rate upward.
Dr. Judith Curry addresses this new paper in her April 24th post “Slowing sea level rise” where she argues that there is no convincing way to adjust out the effects of El Nino/LaNina events from the measured sea level rise record and that natural variability has dominated sea level rise during the 20th century.
The crux of her arguments are presented below with the figure shown from the UN IPCC AR5 WGI report showing that sea level rise has varied significantly since 1900 in a manner which Dr. Curry concludes demonstrates dominance by natural climate variation forces.
The slowing in the measured rate of sea level rise during the last decade has occurred while the RSS satellite measured global lower-troposphere temperature record now has more than half of its 35+ year temperature record, which began data collection in January 1979, showing no global warming whatsoever since August 1996 as demonstrated in the graph below taken from an article in Real Science addressing this “pause”.
Dr. Curry draws the following conclusions based upon these measured and perhaps interrelated outcomes by noting:
“Once again, the emerging best explanations for the ‘pause’ in global surface temperatures and the slow down in sea level rise bring into question the explanations for the rise in both in the last quarter of the 20th century. And makes the 21st century of sea level rise projections seem like unjustified arm waving.”