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Sea level rise has slowed. (It must be time to correct that data!)

Filed under the Semi-Satirical Press.

The Universe is surely conspiring against ecologicist scientists*. Their task is to convince the world that things are dire, and yet just as humans pump out more carbon dioxide pollution than ever before, many natural markers start behaving as if CO2 was having barely any effect at all. It’s all potentially so misleading.

A new paper by Cazenave et al 2014 digs deep to uncover the reasons for yet another unfortunate un-catastrophic trend change.

First, global surface temperatures stopped rising in the late 1990’s. Now, it’s become irrefutable that, for the last ten years, the rate of sea-level rise slowed by thirty percent. Seas were rising at 3.5mm a year up til 2003, then the rate fell to 2.2mm per year for the next eight years. This is exactly what ninety-eight percent of expert Global Climate Models did not predict. The slowing sea level rise is extra problematic because it forms the backbone of the excuse for the long pause in surface warming that wasn’t supposed to happen either.  The fact that it coincided with the global pause in surface temperatures was no comfort at all. The missing heat, after all, must be hidden in the oceans, and that must be causing the oceans to rise even faster than they were before (an obvious, inescapable fact of physics). So now climate modelers are forced to stack excuses — they need an excuse for the excuse. (It’s excuses-squared in the name of science.)

Fortunately, brave scientists have discovered a way to correct the data. The man-made global warming theory is as settled as ever, it is just that the PDO (Pacific Decadal Oscillation) has been affecting trends more in the last ten years than in the years before that (see Judith Curry’s discussion). The extra La Ninas after 2003 have drawn water from the oceans, and dumped it onto Brisbane and Somerset and that has been hiding the true man-made sea level rise. After corrections, the adjusted real sea-level rise is 3.3mm annually. The previous 3.5mm rise in the 1990’s has come down to 3.3mm. Thus and verily, the trend has not slowed at all, it’s really been linear for 20 years. (It was supposed to accelerate. I guess there are more adjustments to come?)

The implications are serious. Do we build sea-walls to deal with the actual sea-level rise (2mm a year) or the corrected sea-level rise (3.3mm)? Presumably a Senate Select Committee for Corrective Sea Services will have to be formed to review the implications. How about we build sea-walls to accommodate the actual rise, then measure those walls with climate-science-calipers and “correct” those measurements post hoc. Thus the corrected height of the sea-wall will always exactly match the corrected height of the sea. You know it makes sense…

But what the PDO giveth, the PDO can taketh away. If  La Ninas reduce sea-levels by dumping water over the land perhaps El Ninos raise the oceans artificially by drying out land-masses and keeping the water in the ocean? Apparently El Ninos rain more on the ocean, and La Ninas more on the land.

Ultimately the slowing sea level rise means one of two things. Either:

  1. It’s bad luck. The El Ninos caused a slightly faster sea level rise to occur in the 1990’s (so all the models overestimated the rise) then the La Ninas arrived and took away the fun just as skeptics were gaining momentum. Or:
  2. It was no accident, and conservatives and skeptics have control of the Pacific Trade Winds. (The bastards.)


Sea level, Global, 1994, 2000, 2014

GMSL rate over five-year-long moving windows   Figure 2: a, Temporal evolution of the GMSL rate computed over five-year-long moving windows shifted by one year (start date: 1994). b, Temporal evolution of the corrected GMSL rate (nominal case) computed over five-year-long moving windows shifted by one year (start date: 1994).


I must say its a marvel that climate scientists didn’t notice how El Ninos were raising sea-levels in the 1990’s. Incredibly bad luck that they didn’t think to ask skeptical questions of the rate back then. Everyone seemed happy (apart from Nils, anyway) to accept the rapid rise at the time. (It’s funny how the Climate ScienceTM downward corrections only seem to happen to the peaks years after the fact but the acceleration of trends occurs in real time.)  I don’t think this study tells us much that is definitive about sea levels, but it shows something about bureaucratized science driven by one-sided grants.

After all is said and done, let’s not forget that the raw satellite measurements of sea levels in the 1990s showed almost no rise at all. So the rise in the 1990’s is already almost entirely thanks to adjustments. These now are adjustments on adjustments.

Worse, Geoff Sherrington also points out that we haven’t measured half the deep oceans, there are mass hydrothermal vents which may be changing in trend and about which we have virtually no data.  “You cannot talk about ocean expansion until you have accurate measurement of the contributions from all sources. The bottom 50% is virtually unmapped.”

Jo says attributing sea level changes 2 kilometers down to “missing heat” from a trace gas 10 kilometers up is “not obvious”. Occams razor on Vodka.

For those who still want to investigate this paper, Graph S3 has the core of it apparently.

Rainfall, Sea level, Cazenave.

Figure S3: Black curve: mean detrended GMSL time series (average of the five satellite altimetry data sets) from January 1994 to December 2011, and associated uncertainty (in grey; based on the dispersion of each time series around the mean). Light blue curve: interannual mass component based on the ISBA/TRIP hydrological model for land water storage plus atmospheric water vapour component over January 1994 to December 2002 and GRACE CSR RL05 ocean mass for January 2003 to December 2011 (hybrid case 1). The red curve is the sum of the interannual mass plus thermosteric components. This is the signal removed to the original GMSL time series. Vertical bars represent the uncertainty of the monthly mass estimate (of 1.5 mm22, 30, S1, S3; light blue bar) and of the monthly total  contribution (mass plus thermosteric component) (of 2.2 mm, ref. 22, 30, 28, 29, S1, S3; red bar). Units : mm.


“Present-day sea-level rise is a major indicator of climate change1. Since the early 1990s, sea level rose at a mean rate of ~3.1 mm yr−1 (refs 2, 3). However, over the last decade a slowdown of this rate, of about 30%, has been recorded4, 5, 6, 7, 8. It coincides with a plateau in Earth’s mean surface temperature evolution, known as the recent pause in warming1, 9, 10, 11, 12. Here we present an analysis based on sea-level data from the altimetry record of the past ~20 years that separates interannual natural variability in sea level from the longer-term change probably related to anthropogenic global warming. The most prominent signature in the global mean sea level interannual variability is caused by El Niño–Southern Oscillation, through its impact on the global water cycle13, 14, 15, 16. We find that when correcting for interannual variability, the past decade’s slowdown of the global mean sea level disappears, leading to a similar rate of sea-level rise (of 3.3 ± 0.4 mm yr−1) during the first and second decade of the altimetry era. Our results confirm the need for quantifying and further removing from the climate records the short-term natural climate variability if one wants to extract the global warming signal10.”

Was this about the “missing energy”? Oh yes it was…

“The term missing energy is related to an apparent inconsistency between interannual variations in the net radiation imbalance
inferred from satellite measurements and upper-ocean heating rate from in situ measurements. Although progress has been achieved and inconsistencies reduced, the puzzle of the missing energy remains, raising the question of where the extra heat absorbed by the Earth is going. The results presented here will further encourage this debate as they underline the enigma between the observed plateau in Earth’s mean surface temperature and continued rise in the GMSL.”

An enigma, I note, that was made more enigmatic by these corrections rather than less so.

Cazenave et al may be right about the ENSO effects on sea-levels, but we know surface temps are not warming, and we know the ARGO buoys didn’t find the missing energy, and we know satellite measures of sea level showed the rate had slowed. The “enigma” is solved by accepting that man-made global warming is a minor force. Or we can do what bureaucratic-science does and adjust the adjustments and make excuses for the excuses until we get the answer our hearts and grants desired.

Last word goes to  Roger Sowell from Judith Curry’s site:

My favorite response to the problem of seas rising is, everyone just eat more fish. There are clearly too many fish in the oceans.









Cazenave, A.,  Dieng, H., Meyssignac, B., von Schuckmann, K., Decharme. B., & Etienne Berthier (2014)  The rate of sea-level rise, Nature Climate Change | Letter   [Abstract] doi:10.1038/nclimate2159


Other posts on Sea Levels:

*Ecologicist Scientist (definition): n. A scientist who uses eco-logic, meaning renewable anaerobic reasoning.

(Sorry, I didn’t set out to satirize this paper. It just happened..)

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