Guest Post by Willis Eschenbach [Painting above, “Uneasy Sea” by Gennady Vytor]
It is not the sea that sinks and shelves,SOURCE
That rock and rise
With endless and uneasy motion,
Now touching the very skies.
For the last forty years or so we’ve been treated to endless scary claims that the rate of sea-level rise is increasing and coastal cities are all going to drown. I’ve shown that part of this hysteria is due to improper splicing of the four sequential satellite records of the sea level. Here are the four records, along with their respective trendlines.
Figure 1. Four satellite sea level records and their linear trends.
As you can see, the first two satellites (Topex and Jason-1) agree, as do the second two satellites (Jason-2 and Jason-3). However, the satellite pairs greatly disagree with each other.
In response to this disagreement between satellites, the “scientists” have just spliced the four records together, ignored the disagreement of the trends of the earlier and later satellites, and declared that the sea level rise is accelerating. Here’s that bit of scientific malfeasance.
Figure 2. The University of Colorado’s improper splicing of the satellite records, claiming acceleration of sea level rise. SOURCE
In the past, I looked at the question of sea level acceleration in a different way. I took the main three global sea level estimates (Jevrejeva, Church & White, and Ray & Douglas), and I looked at the 30-year trailing acceleration. By “trailing acceleration” I mean pick a point in time and look at the acceleration (or deceleration) over the previous 30 years. I repeated this procedure for each year of the record. Here’s that result.
Figure 3. Thirty year trailing acceleration, three global sea level estimates.
This shows something quite curious. Rather than either steadily accelerating or decelerating, the rate of sea-level rise has markedly sped up and slowed down a couple of times over the period of record.
Today I realized that there’s another way I could approach this. To explain it, first let me make a small diversion.
The underlying problem with determining the rate of sea level rise is that the tide gauge sea-level records are not corrected for the rising and falling of the land. Here are some examples:
Figure 4. Sample of longer (75-year plus) sea level records. Colors indicate that I don’t think science should be in boring black-and-white.
Hmmm … you can see the challenge. In some areas, like the region around the North Sea (e.g. first 4 records, left column), the land has been relieved of a huge burden of ice since the last glaciation. As a result, it is rebounding upwards faster than the sea level is rising. And that means that the relative sea level is falling. And along the east coast of the US, the reverse is happening—the land is sinking, so the relative sea-level rise is exaggerated. Finally, in a number of areas, removing either oil or water from underneath the land is causing subsidence. As a result … you can’t trust the tide gauges. All they can give you is the relative sea-level change, not the absolute change.
The second challenge is that most sea-level records are fairly short. Here’s a histogram of the records by length (total years of observations).
Figure 5. Histogram of lengths of all sea level records. Colors as in Figure 4.
My insight today was that I could first detrend all of the long sea-level records. Then I could calculate the 30-year trailing trends, and from those, I could calculate the 30-year trailing acceleration.
So that’s what I did. Out of a total of 1,544 extant tide-gauge records, only 135 of them have records of 75 years or longer. I took those, detrended them, and calculated the average 30-year trailing trends.
Figure 6. Average 30-year trailing trend, 135 detrended 75-year or longer sea level records.
As you can see, the trends have gone up and down, but there’s no apparent overall increase. The largest rate of rise was around 1915.
Finally, as a check on my calculations of the trailing trend, I used the LOWESS smooth to calculate the 30-year trailing acceleration and added it to Figure 3 above.
Figure 7. As in Figure 3, but including the acceleration calculated from the trends shown in Figure 6.
Given that I’m only using a small subset of less than 10% the 1,544 records, I’m quite happy with that result.
A few notes. First, all of those results show that there is no steady acceleration of the rate of sea-level rise that for years we’ve been sternly warned was coming soonest. The rise of the sea level has been quite uneven, accelerating in some decades and decelerating in other decades.
Next, given that we have only sparse information on the rate of vertical land rise or fall at the individual locations of the 1,544 tide stations, determining a global absolute (not relative to land) sea-level rise is somewhat of a guessing game. As evidence of this, here are the rates of sea-level rise from the three global records shown above, those of Jevrejeva, Church and White, and Ray and Douglas.
Figure 8. Average sea-level rise rates, 1900 – 1990. I have used the data only up to 1990 to avoid the scientists’ nasty habit of splicing the corrupt satellite record (see Figure 1) onto the end of the tide gauge records.
My conclusion? Comrade Obama’s two seaside estates, one in Hawaii and one in Martha’s Vineyard, as well as Bill Gates’ $43 megabuck seaside estate in San Diego seen below …
… are in no danger of being submerged, no matter how loudly they scream about the so-called “CLIMATE EMERGENCY”.
Protip: Regarding the climate, you can relax and enjoy life until the day somewhere in the misty future when the people aggressively lecturing you about your “carbon footprint” stop buying beachfront estates and flying private jets.
And for me, I’m going out now, back up the ladder to continue pressure-washing the walls. When will it be done? I can’t think of it that way, doesn’t work for me. Instead, every day when I finish up and stow the tools, I just tell myself “Another tile in the mosaic” and keep going … if I looked at the whole job I might just walk away, but this way I’m always walking toward the fire.
My very best to everyone,
As Is My Custom: I ask that when you comment you quote the exact words you are referring to. This helps avoid many of the misunderstandings that plague the intarwebs.
Further Info: Given that the ocean looks like the painting at the head of the post, how can we measure sea level accurately? The answer is the “stilling well”, used for hundreds of years. It’s a vertical pipe with only a tiny hole at the bottom for the water to enter and leave. As the name suggests, it “stills” the vertical motions and gives us an accurate sea level at any instant. Heres NOAA on the subject.