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U.S. East Coast Sea Level Acceleration: Recent Evidence from Tide Gauges. John Boon Virginia Institute of Marine Science Gloucester Point, Virginia 23062. Sea Level Trends: GMSL vs. RMSL. Linear Trend : Trend estimate from a fitted mmsl* time series of fixed length N.
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U.S. East Coast Sea Level Acceleration: Recent Evidence from Tide Gauges John Boon Virginia Institute of Marine Science Gloucester Point, Virginia 23062
Linear Trend: Trend estimate from a fitted mmsl* time series of fixed length N New York (The Battery), NY 1893-2011 (N = 119 yrs) * monthly mean sea level (seasonal cycle removed) Trend Estimate: 2.97 ± 0.09 mm/yr 1952
Serial Trends: Trend estimates from fitted series of fixed-length n < N ordered in time New York (The Battery), NY 1893-2011 (N = 119 yrs) * monthly mean sea level (seasonal cycle removed) Trend Estimate: 2.97 ± 0.09 mm/yr 1952
Sea Level Trends: GMSL vs. RMSL (n=10 years)
Serial Trends: Trend Estimates from Fixed-length Series Ordered in Time > 78 years
Principal Components Analysis (PCA) 1933-2011 mmsl x 8 stations for varying values of n
Serial Trends: PCA 60-year oscillation? (Chambers, Merrifield, and Nerem GRL 2012)
Constant Acceleration over 1969-2011? (relative sea level rise rate)
Boston, MA F = 89.67 ** Norfolk, VA F = 15.37 ** Charleston, SC F = 0.01 ns Critical Value: F = 6.69 99% confidence level
95% Confidence Bands about individual mmsl heights The 2011 La Niña: So strong the oceans fell Boening et al., GRL 2012
Acceleration: 0.300 mm/yr2 Linear Rate: 2.88 mm/yr
Acceleration: 0.186 mm/yr2 Linear Rate: 5.00 mm/yr
U.S. Army Corps of Engineers Sea Level Calculator 2100 5.85 ft 2050 2.07 ft 1.53 ft
Sea Level Acceleration U.S.-Canadian Atlantic Coast Tide Stations • RSL rise rate history informs serial trends • PCA identifies 60-year cycle in addition to • Period of near-constant acceleration that began about 1987 as evident from serial trends • Acceleration strongest in NE and progressively weaker toward Chesapeake Bay region • Expect mmsl 0.8 to 0.9 m above 1983-2001 MSL by 2050 between Norfolk and Boston • .. If acceleration remains constant