UN IPCC AR5 WGI claims of increasing rates of sea level rise from 1971 to 2010 are unsupported
Guest essay by Larry Hamlin
NOAA has released new and updated mean sea level trend data for it’s Global Network Stations tide gauge locations which are inclusive of measurement data through 2013 (1),(2).
The data include long time period duration (in excess of 30 years) tide gauge station records covering the Hawaiian Islands, Alaska and the Pacific, Gulf Coast and Atlantic coastline regions of the U.S. as well as many other global wide coastal locations. This latest NOAA data shows unchanging linear trends in the rate of sea level rise worldwide with many of these records including 100 year and longer measurement duration periods.
The UN IPCC AR5 WG1 report claims that:
“It is very likely that the mean rate of global averaged sea level rise was 1.7 [1.5 to 1.9] mm yr–1 between 1901 and 2010, 2.0 [1.7 to 2.3] mm yr–1 between 1971 and 2010, and 3.2 [2.8 to 3.6] mm yr–1 between 1993 and 2010. Tide-gauge and satellite altimeter data are consistent regarding the higher rate of the latter period. It is likely that similarly high rates occurred between 1920 and 1950.” (3)
As discussed in detail below the latest mean sea level rise trend data from NOAA simply does not support IPCC assertions that mean sea level rise trends are increasing since 1971. The IPCC report describes the fact that individual location tide gauge measurement values can vary significantly from global average values (4) generally because of the consequences of location specific topography and geology related impacts.
But what the UN IPCC AR5 WG1 report completely fails to address is the fact that the long duration period NOAA mean sea level trend data behavior represent constant and unchanging linear records over time which present major challenges to IPCC claims of increasing sea level rise rates since 1971. The NOAA data is simply unsupportive of IPCC claims of increasing rates of sea level rise in recent decades.
Furthermore the unchanging and constant linear NOAA mean sea level trend records from worldwide tide gauge station data versus the UN claims of increasing rates of sea level rise based on satellite sea level data suggests the latter outcome is driven by anomalous analytical artifacts associated with the measurement and measurement analysis methodology not reflective of real world outcomes.
Since Obama and his “science?” advisers have decided to assert man made CO2 emissions driven sea level rise climate fear claims in speeches (5),(6) involving New York (Hurricane Sandy increased flooding impacts), Virginia and Florida (both with regard to increased high tide flooding impacts) it seems appropriate to examine in more detail the latest NOAA updated mean sea level trend data addressing the various coastline regions of the United States.
Starting with the Hawaiian Islands, the birthplace of Obama, we see below the primary long duration NOAA tide gauge station records at Honolulu and Hilo showing completely unchanging linear rates of sea level rise measuring between 6 to 13 inches per century (7). These NOAA records are presented in map location format and individually for ease of review. NOAA records show no increasing sea level rise acceleration in the Hawaiian Islands refuting claims that man made CO2 emissions are increasing rates of sea level rise here or in fact anyplace else on the globe.
Moving next to Alaska the primary long term NOAA tide gauge locations are shown for Adak Island, Seward, Sitka and Ketchikan (8). All of these records reflect constant linear decreasing rates of sea level rise driven by tectonic uplift forces which dominate this region (9). The tide gauge records of Adak and Seward show large step change impacts caused by the major earthquakes of 1958 (magnitude 7.3) and 1964 (magnitude 9.2) respectively at these locations. Man made CO2 emissions have no bearing on sea level rise impacts in Alaska.
The Pacific, Gulf Coast and Atlantic regions of the continental U.S. are shown next with primary long duration period NOAA tide gauge data reflecting unchanging linear rates of sea level rise varying between 3 to 12 inches per century (10) at these locations. Two outliers exist in this data at Astoria, Oregon and Galveston Pier 21, Texas. Astoria is experiencing constant linear declining rates of sea level rise driven by tectonic uplift forces (11) and Galveston is experiencing constant linear rates of sea level rise of about 25 inches per century driven by regional land subsidence due to long term oil and gas extraction (11).
There is simply nothing in these NOAA long duration mean sea level trend data records that supports claims that man made CO2 emissions are accelerating sea level rise at U.S. locations. Without belaboring the point the same holds true for locations worldwide as demonstrated by the latest NOAA global wide mean sea level trend data.
Obama made alarmist and absurd remarks at a recent address (6) claiming that man made CO2 emissions were contributing to sea level increases at Norfolk, Virginia and Miami, Florida such that high tides at these cities were causing increased flooding.
Shown below is the NOAA primary tide gauge data for Florida (12) for Pensacola, Key West, Miami and Mayport. The Miami sea level trend data terminates in about 1983 but the 50 year record up to that time is an unchanging linear record with a rate of increase of about 9 inches per century. The NOAA long period duration mean sea level trend records for the other Florida locations show similar rates of unchanging linear increasing sea level trends as Miami. There is simply nothing in the NOAA mean sea level trend data that supports Obama’s ridiculous remarks about Miami’s man made CO2 emissions caused increased flooding.
Obama’s equally ridiculous and absurd remarks about man made CO2 emissions caused increased flooding at high tide in Norfolk, Virginia were well addressed at WUWT (13). Shown below are the NOAA mean sea level trend data for Sewells Point and Portsmouth, Virginia which are both located very near Norfolk (14). Both records are unchanging linear trends with the Portsmouth 50 year long record terminating in about 1988. This region is significantly impacted by subsidence which contributes about 60% of the 17 inch per century linear rate of sea level rise at Sewells Point. NOAA data does not support claims that man made CO2 emissions are causing increased flooding at high tide in Norfolk, Virginia.
Obama has also made alarmist remarks alleging that man made CO2 emissions increased sea level rise resulted in greater flooding impacts during Hurricane Sandy in New York City (5). Shown below are NOAA long period duration mean sea level trend records for Kings Point and The Battery, New York and Atlantic City, New Jersey (15). The NOAA data shows clearly that sea level rise trends at these locations are linear and unchanging with the New York locations having rates of sea level increase of about 11 inches per century. The higher rate of sea level rise at Atlantic City location versus New York is the result of land subsidence (16). NOAA data shows that man made CO2 emissions have not caused increases in sea level rise that made Hurricane Sandy’s flooding worse.
Climate alarmists including Obama and his “science?” advisors are deliberately misleading, some might say lying, to the American people trying to push high cost, bureaucratic and completely ineffectual mandates for CO2 reductions here that won’t do anything to impact global climate or reduce the ever increasing global rise in utilizing economically advantageous coal fuel energy.
(3) UN IPCC AR5 WG1 SPM report, Section B.4 Sea Level, pg.11
(4) UN IPCC AR5 WG1, Chapter 13, FAQ 13.1, pg. 1149
(7) Hawaii: Honolulu,
(8) Alaska: Adak,
(10) Continental U.S.
San Francisco, California:
Los Angeles, California:
San Diego, California:
Galveston Pier 21, Texas:
Key West, Florida:
Charleston, South Carolina:
The Battery, New York:
(15) New York:
Atlantic City, New Jersey: