Sea Level Deceleration: Inverted Barometer

Previously I showed that the “rise in the sea levels” was decelerating.  I did this using data from the University of Colorado “No Inverted Barometer Applied” data.  I was challenged in my choice of data as the Inverted Barometer data is adjusted for atmospheric disturbances (high and low pressure systems) that affect the satellite data.  I prefer to work with the unadjusted data which is why I made the choice I did.  I commented with a rough calculation that the inverted barometer gave even more deceleration than the unadjusted data and left it at that.

As I got busy with my move I left it at that.  I kept thinking more about it and decided to revisit the issue.  So I went back and re-did all the work and set it up so I would easily be able to apply the same methods to the different types of satellite sea level data.  My rough estimate that the inverted barometer (IB) is showing greater deceleration than the unadjusted data (No-IB) stands.  It is more refined now, but the result is clear.  There is no chance that the IPCC is correct that the sea level will rise 1m by 2100 based on anything seen in the actual data.

I started off in the same manner by taking 5 year trends of the IB data.

The Inconvenient Skeptic

The Inverted Barometer data with 5 year trends shown throughout the period. The decrease in rate is evident in the more recent data.

An acceleration would be present if the slope of the lines were becoming steeper over time.  A deceleration would mean that the slopes are becoming flatter over time.  Just from this chart it is clear which type of behavior is present in the IB sea level data.  Any claim that the sea level rise is “accelerating” is simply disproved by this very simple method.

If the 5 year rates are shown together the result is comparable to the results of the No-IB I did before.  It is clear that the rise is less in recent years.

The Inconvenient Skeptic

Recent periods show that the rate of rise is decreasing. That makes a 1m increase in sea level very unlikely.

There is a slight difference in the rates for the 5 year periods with the IB.  1997 has the highest rate of rise at 4.3mm/yr.  At that rate it would only take 231 years for the sea levels to increase 1m.  So at the very fastest rate recorded it would still be 2228 before the sea levels increased 1m.


The real problem for the IPCC predication is that the rate has been lower for every period since 1997.

The Inconvenient Skeptic

The trend in the rates is decreasing. That is the perfect description of deceleration. Technically deceleration is a negative acceleration, but only the IPCC would have the gall to be that misleading.

Much like gravity provides an acceleration for objects that are falling towards the Earth, the Earth is also giving the IPCC a decreasing rate in sea level rise over the past 10 years.  Far more significant is the fact that there has not ever been an increase in the rate of rise of the sea level.  Even in the period from 1995-2002 when the rate was higher, there was no indication that the rate was accelerating.  There was a constant rate of change that has strongly trended negative over the past 10 years.  There is no scientific basis for the statement that the sea level rise is accelerating.

The actual acceleration is -0.15 (mm/yr2).  That is a deceleration of 0.15 (mm/yr2)

The peak sea level from the IB will happen in about 15 years at about 46mm above the 2000 benchmark.  According the deceleration of the IB data the sea level in the year 2100 will be more than 400mm lower than it is now.  The more “accurate” inverted barometer data shows that the IPCC is even farther off in their prediction of the sea level in 2100.  If the deceleration remains constant (which I freely admit is unlikely) the sea levels up to the year 2100 will look like this.

The Inconvenient Skeptic

If the trend in the rates stays constant the sea levels will drop almost 400mm from where they were in 2000.

Both sets of data show that the sea level will drop over the next 100 years.  None of the sea level data shows any indication of accelerating in the positive manner.  If the sea level is the global fingerprint of global warming, then there is no indication of global warming.

On a final note, if the sea level is dropping, then there is only one place that water of that mass could disappear too.  It isn’t the atmosphere and it isn’t aquifers.  It is locked up in ice sheets and glaciers.

Posted in Ocean: Sea Level and SST by inconvenientskeptic on February 16th, 2011 at 4:04 pm.


This post has 6 comments

  1. Richard Feb 17th 2011

    I didn’t expect that the message would change from using the un-corrected value but it is good to see that it is so.

    The most worrying thing about all of the IPCC scenarios is that, if they are wrong and this is all mainly a long natural cycle that we are seeing and not CO2, then where does that leave us? Are we in fact at or near the upper limit of whatever natural cycles there are?

  2. T.G.Watkins Feb 17th 2011

    Thermal contraction as SST cool ?

  3. inconvenientskeptic Feb 17th 2011

    Thermal contraction is likely a major component. That said the seasonal component is related to snow in the Northern Hemisphere.

    The ocean evaporation rate is ~2.5 mm/day (as is precipitation) so it is reasonable that NH winter causes ocean drop and that is part of the seasonal signal.

    Here is some info on the inverted barometer…

  4. One of NOAA’s Climate Indicators is Glacier Mass Balance…

    It looks like glacier mass balance has been increasing since ~2003… Just about the same time that sea level rise began to decelerate.

  5. John,

    I’ve been linking to this post from other blogs – thanks for taking time to do this.

  6. garrymoore Nov 24th 2011

    hi to all theinconvenientskeptic.comers this is my first post and thought i would say a big hello to yous –
    speak soon

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