RSS
Image

Sea Level Deconstruction

30 Jan

The latest Sea Level data from the University of Colorado

http://sealevel.colorado.edu/files/2011_rel4/sl_ns_global.png

This is a response to Willis Eschenbach’s post at WUWT, http://wattsupwiththat.com/2012/01/29/hansens-sea-shell-game/ .  I thought I would check whether sea level rise is accelerating, or decelerating.  This is pretty easy to test.  I also superimposed the best fit sine wave to capture any longer term cyclical behavior.

I was unable to model anything that would allow best fit using an accelerating parameter on an exponential function.  Deceleration did improve the least squares error, with or without the sine wave.  The factors are shown in the chart below (click to enlarge):

Note that the recent data shows obvious deceleration, as the best fit sine wave and -acceleration factors both show.  Note also that the best fit trend is only 2.24mm/year, well under Hansen’s estimates.  The rest of the total impact is a cyclical element with an amplitude of 7.04mm and a 25.3 year wavelength (of the last cycle at least).  You can see that the residuals are well centered around zero.

And since Hansen is so willing to make projections of things that are NOT in the data, I’m going to take the liberty of doing all those things Willis tells us not to do in the following chart – project these same factors over the next 88 years to 2100:

So there you have it… Declining sea levels until 2019, then rising again to 2033, and pretty much down hill from there.  Hmmm…  If my projection is based on actual data, does that make mine more credible than those a “real” climate scientist?

 

Update 2013/11/30:

SineWaveSolver20131130SeaLevel.xls

Acceleration is still negative in 2013 after removing the main cyclical component.  Recovery from the 2011 sea level blip cut the acceleration in half.

SineWaveSolver20131130SeaLevel2.xls

 

About these ads
 
Leave a comment

Posted by on January 30, 2012 in Climate

 

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

 
Follow

Get every new post delivered to your Inbox.

%d bloggers like this: