Sea Level Predictions Revisited
UPDATE #1: A more succinct paper written by Nils-Axel Morner further supports my claim on sea level deceleration can be found in this PDF :
Here is Morners Bio:
Renowned oceanographic expert Nils-Axel Mörner has studied sea level and its effects on coastal areas for some 45 years. Recently retired as director of the Paleogeophysics and Geodynamics Department at Stockholm University, Mörner is past president (1999-2003) of the INQUA Commission on Sea Level Changes and Coastal Evolution, and leader of the Maldives Sea Level Project.
UPDATE #2: In addition to both Nils-Axel Morner and Houston & Dean, a supporting paper on sea level deceleration comes from Australia:
by P. J. Watson
Here is excerpt of that abstract:
“These long records have been converted to relative 20-year moving average water level time series and fitted to second-order polynomial functions to consider trends of acceleration in mean sea level over time. The analysis reveals a consistent trend of weak deceleration at each of these gauge sites throughout Australasia over the period from 1940 to 2000.”
So what we have here is 3 papers, all showing a deceleration of sea levels, in 3 different regions around the globe, an no one is talking about it.
Hence, I will talk about it here.
Since my last post, Sea Level Predictions, I felt it was necessary to key in on some new key points.
Reuters released this ‘alarmist’ article by Deborah Zabarenko, Environment Correspondent, entitled:
WASHINGTON | Wed Feb 16, 2011 5:51pm EST
“(Reuters) – Rising seas spurred by climate change could threaten 180 U.S. coastal cities by 2100, a new study says, with Miami, New Orleans and Virginia Beach among those most severely affected.”
But on the other side of the issue comes a scientific article from the Journal of Coastal Research:
ABSTRACT HOUSTON, J.R. and DEAN, R.G., 0000. Sea-level acceleration based on U.S. tide gauges and extensions of previous global-gauge analyses. Journal of Coastal Research, 00(0), 000–000. West Palm Beach (Florida), ISSN 0749-0208. Without sea-level acceleration, the 20th-century sea-level trend of 1.7 mm/y would produce a rise of only approximately 0.15 m from 2010 to 2100; therefore, sea-level acceleration is a critical component of projected sea-level rise. To determine this acceleration, we analyze monthly-averaged records for 57 U.S. tide gauges in the Permanent Service for Mean Sea Level (PSMSL) data base that have lengths of 60–156 years. Least-squares quadratic analysis of each of the 57 records are performed to quantify accelerations, and 25 gauge records having data spanning from 1930 to 2010 are analyzed. In both cases we obtain small average sea-level decelerations. To compare these results with worldwide data, we extend the analysis of Douglas (1992) by an additional 25 years and analyze revised data of Church and White (2006) from 1930 to 2007 and also obtain small sea-level decelerations similar to those we obtain from U.S. gauge records. ADDITIONAL INDEX WORDS: Global climate change, Sea level rise.
The one statement that stands out is, “…. we obtain small average sea-level decelerations.”
And in their concluding statement, this quote is made:
“It is essential that investigations continue to address why this worldwide-temperature increase has not produced acceleration of global sea level over the past 100 years.”
Lets look at sea levels in a different way, other than the way we are told by the MSM (Main Stream Media).
Following in the direction of Houston and Dean, I wish to provide some of my own analysis of sea level trends.
New Orleans has become the poster child for accelerated sea levels since Hurricane Katrina.
What I believe is that rising sea levels for New Orleans, or any region, supposedly effected by AGW, are not properly documented or presented by MSM.
My first graph I would like to present is a current view of annual sea level rise for North America:
(All of the visual aids and data presented below are courtesy of NOAA Tides and Currents)
Current Sea Level Rise for North America
The above graph shows, using upward and downward pointing arrows, the annual trend for sea level anomolies, with the New Orleans region showing the most dangerous rise. The long red arrows, make it quite obvious.
Lets look more closely:
Popup Text for New Orleans
The popup text denotes a 3 foot rise in sea level for a 100 year period, using a 9.24 mm/year mean annual trend since 1947.
Lets now look at the interannual trend since 1980:
Reprinted from NOAA Tides and Currents website
The interannual trend suggests, that while sea level rise for New Orleans(Grand Isle Region), is still rising, it is rising at a slower pace than the 9.24mm/year of annual mean since 1947. So, while the sea level rise for New Orleans is continuing a upward trend, the rise has been slowing down for the last 30 years.
Update #3: Something that also has not been considered is subsidence. Based upon this report by ASCE, land mass is sinking in the Orleans Parrish, anywhere from .15 to 1.0 inch a year. These figures, if introduced into the sea level deceleration, would show not only a lower sea level rise, but an even stronger sea level deceleration.
A Report by the American Society of Civil Engineers
Hurricane Katrina External Review Panel
However, due to major flood control structures being built upstream
on the Mississippi River and levees being built around New Orleans, fresh
layers of sediment are not replenishing the ground lost by subsidence. The
natural subsidence has also been exacerbated by groundwater withdrawals,
petroleum production, development, and other factors. Based on data
collected by the United States Geological Survey from benchmarks located
primarily in Orleans Parish (1951-1995), subsidence has been estimated to
occur at an average rate of about 0.15 to 0.2 inches per year, although rates in
excess of 1 inch per year occur in some locations
This is quite opposite from what MSM and the alarmism they report. What we hear from MSM is that due to rising Co2 emissions, global temperatures will accelerate the rate of sea level rise for the next 100 years or more. This is simple not true.
At the other end of the spectrum, Juneau, Alaska sea levels have been dropping. Take a look:
Juneau Popup from NOAA Tides and Currents website
The mean annual sea level trend for Juneau is -12.92 mm/year since 1936. Most of the decline in sea levels for Juneau is attributed to subduction of plate tectonics. But lets take a look at the interannual variation anyways, for analysis purposes:
Image Provided from NOAA Tides and Currents
The trend here is a rate of decrease in sea level decline. While this data may or may not contribute for a trend in rate of decrease in sea level rise, we are presented with data suggesting that there doesn’t seem to be any homogeneous trend for sea levels.
Geological factors, i.e. subduction, erosion, volcanism, and sedimentary deposits all play a role in how sea levels are effected, at a global level.
The purported 3mm/year rise for global sea levels rise, due to global warming, is misleading at best.
If we take into account geological anomalies and the rate of decline in interannual variations in sea level, we may or may not have any rise of sea levels at all. We may be seeing a trend of less sea level rise, but more studies need to be undertaken.
All I suggest is we start looking at other ways to view how the environment is effected by cycles, and not put ourselves in a position in blaming Co2 emissions for everything wrong with this planet.
Good Day !