In this post I'm getting back to looking at Dave 'NC-20' Burton's narrative. We've been having a bit of a debate over at the comments section of WUNC's article by Dave Dewitt titled, "The Changing Carolina Coast: Managing the Threat of Rising Water." Dave jumps around a lot so I'm focusing on specific quotes. In this case I want to answer some of his responses to my previous post.
In that write up I included many links to sources indicating observed accelerating sea level rise, but NC-20 keeps trying to drag attention back to the last century and what he fancies "insignificant" sea level rise. He also makes much of "no coastal Sea Level acceleration," but he leaves out all the details since they would undermine his claims. I chose to look at those details and learn. In this post along with my commentary I'll be sharing authoritative sources so the interested can learn and decide for themselves.
Consider our Earth as a real physical entity, it's cryosphere (glaciers, sea ice) have been in a stable condition for the past few thousands of years, since the end of the last ice age. The documented warming of the past century acted to soften up and fracture that ice mass, like a block of ice left on a warm sidewalk. Of course melting (and water contribution) is slow during these initial phases of warming! That's no cause for ignoring what is happening this century.
Perhaps his biggest deception is making an issue of the stately rate of sea level rise during the last century, then pretending it's a guide to this century. Such deliberate misperceptions needs to be confronted.
NC-20 Burton writes: Thank you, CC for the links, and for verifying what I told you, even if you apparently didn't read it.
Also, please notice, it was no up-tick followed by a drop. It's been relentlessly uphill ever since. Thus NC-20 is left with nit-picking the "acceleration rate" during the previous century with all his might. All the while doing his best to ignore the observed acceleration in our 21st century.
Earth's processes don't march to NC-20's unrealistic expectations.
It's foolishness to expect an exact tracking between sea level rise and the sudden ramping up of greenhouse gases (read global insulation) during this past century. An appreciation for Earth's processes makes it abundantly clear why a bit of lag and variability is to be expected.
Here's another example of focusing on a sliver of reality and ignoring the big picture. Coastal sea level, is "Relative Sea Level". Dave thinks we should dismiss "Absolute Sea Level" because it often doesn't correlate with sea level changes along the coastline. That there are well understood reasons for this he also ignores.
NC-20 asserts that tide gauges are the gold standard and that we should throw out the satellite record, because it's subject to more corrections and revisions than Tide Gauges. He reveals his foolishness by pretending that Tide Gauges hardly undergo any adjustments. Look into it, you'll find out, as I did, that Tide Gauges need way more corrections that NC-20 dares hint at.
Historical Tide Gauge MeasurementsEdited: May 17, 2011~ ~ ~ ~ ~ ~ ~What is glacial isostatic adjustment (GIA), and why do you correct for it?Edited: July 29, 2011http://sealevel.colorado.edu/content/what-glacial-isostatic-adjustment-gia-and-why-do-you-correct-it~ ~ ~ ~ ~ ~ ~For a taste of the complexity of Tide Gauges:~ ~ ~ ~ ~ ~ ~~ ~ ~ ~ ~ ~ ~
In their echo-chamber it's expected to demonize "computer models" - in real life it's ludicrous. Nothing in modern science can happen without the use of computer models to help process data. Nor in real life. Planes couldn't be built and air traffic control would be impossible without "computer models" doing the heavy lifting - neither would weather maps or forecasts and so it goes, on and on from there.
As for the deeper question. It's true satellite's can't substitute for tide gauges any more than tide gauges can do a satellite's job.
They are not directly comparable because at the coast, the land itself, is moving up and down due to a variety of geological phenomena. There are other issues added into the mix to complicate deciphering tide gauge numbers: currents, prevailing winds, geography and such.
Comparison of From Glaciation to Global Warming - A Story of Sea Level Change
Satellite Altimetry to Tide Gauge Measurement of Sea Level: Predictions of Glacio-Isostatic Adjustment
I say this because he seems unaware that our global climate system had been settled into a wonderful plateau for the past many thousands of years. When he/they look at the paleo sea level chart that long running plateau makes not the slightest impression on them.
Inability to appreciate it’s significance doesn’t make it any less significant.
how much it costs is up to us
"Abstract We estimate the rise in global average sea level from satellite altimeter data for 1993–2009 and from coastal and island sea-level measurements from 1880 to 2009.
For 1993–2009 and after correcting for glacial isostatic adjustment, the estimated rate of rise is 3.2 ± 0.4 mm year−1 from the satellite data and 2.8 ± 0.8 mm year−1 from the in situ data.
The global average sea-level rise from 1880 to 2009 is about 210 mm. The linear trend from 1900 to 2009 is 1.7 ± 0.2 mm year−1 and since 1961 is 1.9 ± 0.4 mm year−1. ..."
Incidentally, here’s an interesting talk by Marco Olivieri about a new adaptive technique that extracts periodicities from time-series. Complex stuff, but quite interesting. These results also indicate accelerating sea level.
We explore the possibility to use EMD (Empirical Mode Decomposition) to improve the robustness of Global Sea level acceleration assessment for the last century. EMD is an adaptive technique that extracts periodicities from time-series. This was systematically applied to RLR monthly Tide Gauge data archived at PSMSL to determine the monotonic function that represent the a-periodic component of each time series. By implementing robust statistics and methods derived from econometrics we then reconstructed Sea level function at global and regional scale. A newly determination for the global mean sea level rise and its variations is proposed and discussed in terms of statistical significance for constant rates and constant acceleration with respect to abrupt changes occurring in a limited period of time.