Sea-Level-Rise Acceleration

Judith Curry’s latest thoughts (this is part of a series, to be continued).

The more times goes on, the less concerned I get about climate change (not that it may not change for the worse — that’s always a possibility — but in the sense that we really understand and can predict it). For example, consider the Iceland event of 1783. If that happened today, it would be much larger than anything we’ve been doing with CO2, and it’s entirely unpredictable.

As always, our best bet is to get as wealthy as possible so we’ll have the resources to deal with whatever the future holds. Instead the climate alarmists advocate polices that make energy needlessly more expensive (and hence everything more expensive, inhibiting economic growth).

[Update late afternoon]

Judith’s weekly climate roundup, which is usually interesting.

28 comments on this post.
  1. ken anthony:

    Has anybody noticed that we live on a ball? That means temperatures rising or falling is both good for some places and worse for others. As it’s always been. I can get more temperature change driving from a valley to a mountain in less than 100 miles than the whole earth will experience in anyone’s lifetime.

    Perspective is a wonderful thang.

  2. Curt Thomson:

    And inhibiting the poor from improving their circumstances, thereby ensuring their lives remain brutal and short. Leaving them with no other option than reproducing at elevated rates.
    Of course the left sees that as a feature: more people without agency dependent on a global elite for their survival.

    “Give us more of your property so that we can care for the untold billions that, because we’ve made energy so expensive, remain numerous, destitute and in need.”

  3. cthulhu:

    As the late Jerry Pournelle used to write, with cheap unlimited energy, all problems are shallow.

    If we were serious about this, we would be investing in advanced nuclear power development.

  4. NavyNuke:

    Or LEU nuclear-oil shale hybrid systems. I read a very interesting journal article on this approach a couple years back. Effectively tap the 1.5T barrels in the western US and watch global politics change.

  5. George Turner:

    If sea level rise were accelerating then the data would clearly show up in Earth’s spin rate as water’s mass was transfered from the arctic to the equator. The fact that there are zero published academic papers from astronomers claiming to have that independent confirmation of sea level rise tells me there is no unusual sea level rise.

    Stellar positions and atomic clocks can’t be fudged as easily as a satellite calibration or a stick shoved in the mud, and conservation of angular momentum isn’t something that has big fat error bars.

  6. Andrew_W:

    Interesting idea, but Earth’s rate of spin is slowing down as it’s braked by lunar and solar tidal action, do we know exactly at what rate it’s slowing?

  7. Andrew_W:

    I should have said: “Do we know excactly at what rate tidal action should be slowing it? If not, we can’t be certain how much to attribute to any changes in the Earth’s mass distribution, such as tectonic movement, natural water movement like currents, and of course SLR.

  8. ken anthony:

    Andrew, those are trivialities. Nothing you said invalidates George’s point. Which is that it’s an extremely accurate, measurable metric regardless of other factors that might play into it.

  9. Andrew_W:

    Ken, you say that because you didn’t actually get the point I’m making. The clocks are amazingly accurate, but without a similarly accurate knowledge about the rate of tidal slowing we can’t accurately distribute the observed slowing between the causes.

  10. Karl Hallowell:

    In other words, instead of looking for a relatively obvious measure of sea level rise, we should look for one that is probably well below the noise level (we’re looking at short term change in an already noisy parameter) – one of the classic ways of generating pseudoscience. And if the more easily to observe measure doesn’t show the expected degree of change, then why is its derivative expected to show that?

    Fundamentally, the “but we haven’t measured this thing yet” argument is an example of the argument from ignorance fallacy.

    And let us recall that the climate change debate is chock full of confirmation bias. We hear about all the data that can be contrived to support the position of panic, but not the data that isn’t so strongly in support.

    For example, where is the discussion of the likelihood that the long term temperature sensitivity of a doubling of CO2 is significantly lower than the advocated 3 C per doubling? That is, we’re not seeing a lot of positive feedback in climate systems to justify that number?

  11. ken anthony:

    I got your point and one more that you don’t. Tidal effects of the moon are NOTHING relative to what the effects of rising sees would be. George is making an indisputable point (that, due to lack of proportionality you choose to dispute.)

    You would find if you do the math that all these other causes you think are significant are not. We’re talking about a shitload of water that would be easily perceived in the rate of rotation well within the extreme tolerances we know them to be. Like George said, this is hard science, not social science..

  12. George Turner:

    Yes, we do know to a pretty tight degree. Munk’s paradox is that Earth’s 20th century spin rate data, up through the late 70’s, couldn’t be reconciled with the accepted sea-level rise. This paradox was later solved, with a much lower rate of rise (about 1.2mm/year as I recall) by coming up with a better model of magma shifts.

    Not only can they if ice is melting, they can tell whether it’s happening in Greenland, which changes the Earth’s spin axis. They can even detect shifts in atmospheric rotation around the artic. And yet, zero papers from the astronomers screaming that sea level rise is accelerating.

    Here’s a graph of 20th century day length variations. It has no obvious trend.

    Here’s another paper on day length variations since Babylonian times. Ancient astronomers kept notes on things like eclipses, which allows us to back calculate spin rates.

  13. Jim Davis:

    If sea level rise were accelerating then the data would clearly show up in Earth’s spin rate as water’s mass was transfered from the arctic to the equator. The fact that there are zero published academic papers from astronomers claiming to have that independent confirmation of sea level rise tells me there is no unusual sea level rise.

    Careful here, George, this is a sword that cuts both ways. One can also imagine Bill Nye saying something like, “Isn’t it strange that the global warming deniers never use the Earth’s rotation rate to rebut the notion that the sea level is rising and hence the planet is warming? Could it be the data doesn’t support their position?”

    I suspect that the answer would be the same in both cases: The effect from the claimed sea level rise would be well within the error bars of the measurements.

    But in any case we would have to see the data. Any claim that “The other guys aren’t using this data, therefore this data must support my position” is a total non sequitur.

  14. Rand Simberg:

    I can imagine someone being smart enough to say that, but not Bill Nye.

  15. wodun:

    I suspect that the answer would be the same in both cases: The effect from the claimed sea level rise would be well within the error bars of the measurements.

    An answer in the error bars would support the rational side because it would show no significant increase in sea level.

    Isn’t it interesting that someone comes up with a way to check widely held assumptions and the response is to point out the uncertainty of measurement? But pointing out the uncertainty of measurement regarding widely held assumptions can get one labeled a science denier and cast out of polite society.

  16. MikeR:

    So do the calculations and let’s see it. It’s an interesting idea, but you have to actually do it to use it as evidence.

  17. Andrew_W:

    Munk’s enigma

    https://www.zmescience.com/science/geology/earth-axis-rotation-sea-level-rise-053434/

    And absence of evidence isn’t evidence of absence.

  18. Leland:

    If evidence is absent, then the science is always just a theory without supporting evidence.

  19. Andrew_W:

    I was referring to George’s claim that an absence of papers on Munk’s Enigma was evidence that Earth’s current rate of spin doesn’t support the other evidence of SLR, of which there is plenty.

  20. wodun:

    Plenty of evidence with plenty of uncertainty from a wide range of factors. Each additional factor that feeds sea level determinations adds another layer of uncertainty, similar to the probability of product failures.

  21. George Turner:

    In this case evidence of absence is proof of absence. Conservation of angular momentum of an isolated system is conserved, down to the nth decimal place. The Earth has no unknown mechanical torques. There are the tidal forces from the moon and sun and those are known to an extreme degree of precision. Orbital mechanics doesn’t have fudge factors like tree rings do. You can plot a course to Mars a hundred years in the future and hit the target within meters. You can calculate Mars’ position in the sky thousands years in the past, and be exactly right.

    Interestingly, the extreme precision and accuracy of orbital mechanics and local physics (Newtonian mechanics) is what created so much faith in science. Climate alarmists exploit this trust even though they’re field offers typical scienctific results as “2 plus or minus 1, maybe plus or minus 1.5”, relaying on the trust built by physicists who freak out if a constant’s eighth decimal place isn’t nailed down.

    The Earth’s spin rate is one of those pieces of hard science that can’t be fudged. The unknowns are very slow geological shifts in the deep Earth. When we have a major plate slip, such was with the last Asian tsunami, they tell us how much it will affect the Earth’s day length because you can calculate that to sub-millisecond precision.

    The spin rate is an error check that can’t be bargained with or waved away. It’s hard physics.

  22. wodun:

    Curry’s post illustrates how complex the uncertainties are. It is good to see commenters here embracing uncertainty as well.

  23. MfK:

    I take issue with the concept of “global mean sea level.” To first order, it would be defined by a constant potential surface (constant “local gravity”). In hydrostatics, a fluid surface will seek that level…at least under certain ideal circumstances.

    The seas are not static, however, and I doubt if the constant potential surface (which is measurable to phenomenal accuracy) corresponds much at all to the actual time-averaged surface contour of the seas. Just as an example, anywhere there is a current, the level will be below the constant-potential surface. The density distribution of the oceans is a complete unknown, and sea level (locally and globally) depends on density. The change in surface level with respect to density is quite large – on the order of 4 meters per 1 kg/m^3 density change. That density change is only 0.0974%. It can be influenced by both temperature and salinity changes. We don’t have enough data worldwide to get a good handle on either, let alone both. And sources of change in both are not well characterized. For example, hydrothermal vents weren’t even known prior to 1977. They emit jets of supercritical water (density ~ 1/3 that of the surroundings), along with salinity-altering minerals. We have no idea how many there are, or what their contribution is.

    Finally, there is the matter of the volume of the basin in which all that water resides. It isn’t constant, and we have no accurate handle on how it is changing. But that probably (not definitely) has a larger effect on sea level than any other variable. To speculate that “global mean sea level” is rising is to speculate on something that may have no identity at all.

  24. Bob-1:

    http://sealevel.colorado.edu/content/what-definition-global-mean-sea-level-gmsl-and-its-rate

    What do you think?

  25. George Turner:

    The trouble is that their results aren’t in absolute numbers becasue they are measuring beyond the precision of their instrument and beyond the precision of the satellite’s orbit. So the results are adjusted to reach agreement with the guys who reanalyze the results of other guys who shove sticks in mud. As Judith Curry pointed out, estimates of prior 20th century sea-level rise have been adjusted downwards. The satellite data will be adjusted to reflect that because they can’t accurately and independently show changes on the order of a fraction of a millimeter per year.

  26. Bob-1:

    Did you see the graph on their main page? It shows change much larger than a fraction of a mm per year (starting in 1993).
    http://sealevel.colorado.edu/

  27. Bob-1:

    It is interesting to poke around the site, starting with the FAQ: http://sealevel.colorado.edu/faq

  28. MfK:

    This is better.

    http://www.esri.com/news/arcuser/0703/geoid1of3.html