Regular readers know that I have been searching for the origin of the thermal expansion hypothesis.
By origin, I mean the seminal peer-reviewed paper that establishes that concept as a valid, i.e. falsifiable, hypothesis.
The suspicion I have is that the hypothesis seems to have been developed prior to ARGO floats and deep water measurement robustness which are required to properly assert such a hypothesis.
II. Questionable Use of Scientific Papers To Assert
Thermal Expansion Concepts
Thermal Expansion Concepts
Yet, even without that required factual background, the hypothesis is often expressed by questionable scientific sites as it is in the following quote:
"As the ocean warms, the density increasing causing the water to expand in volume. Thermal ocean expansion is one of the major contributors to sea level changes during the 20th and 21st centuries."(Climate Signals, [Wayback Machine Copy], emphasis added). This statement
The site link I quoted it from is promoted (they assert), by associates, decendants, or the like of one of the founders of Oil-Qaeda (J. D. Rockefeller) in the form of a philanthropy website (Rockefeller Philanthropy Advisors) to wit:
Climate Signals is a science information project of Climate Nexus, a non profit organization under the fiscal sponsorship of Rockefeller Philanthropy Advisors, a 501(c)3 organization.(Climate Signals, [Wayback Machine Copy] emphasis added). That website refers to a paper (Improved estimates of ocean heat content from 1960 to 2015), which is a questionable citation in the sense that the paper in no way substantiates the mantra "Thermal ocean expansion is one of the major contributors to sea level changes during the 20th and 21st centuries."
Originally launched in 2010 as an independent project, Climate Signals underwent graphic redesign and content expansion in 2016 as a project of Climate Nexus.
As is typical, the authors of the paper do not contemplate the deep ocean (the abyss), ruminating their hypothesis about heat content (not thermal expansion), using mainly the upper ocean level data, and certainly making no assertions about the validity of the thermal expansion mantra.
III. A Closer Look At The Paper
The main theme of the paper, IMO, is that the Earth's energy imbalance (EEI) and ocean heat content (OHC) have been underestimated:
"Earth’s energy imbalance (EEI) drives the ongoing global warming and can best be assessed across the historical record (that is, since 1960) from ocean heat content (OHC) changes. An accurate assessment of OHC is a challenge, mainly because of insufficient and irregular data coverage." [p. 1, PDF](ibid, "Improved estimates of ocean heat content from 1960 to 2015"). Thermal expansion is mentioned once in the paper (p. 8, PDF), and thermosteric is mentioned twice (p. 9, PDF), both without robust elaboration.
"However, ASL [altimetry sea level] is a combination of full-depth thermal expansion and ocean mass change and is not directly representative of OHC [ocean heat content] change. Further, ASL is a two-dimensional metric without depth information, but the ocean sampling changes markedly with depth." [p. 8, PDF]
If anything, the paper is contrary to the thermal expansion hypothesis I am posting about today:
We found that changes in OHC are relatively small before about 1980; since then, OHC has increased fairly steadily and, since 1990, has increasingly involved deeper layers of the ocean." - [p. 1, PDF](ibid). How can thermal expansion be relevant when heat content was "relatively small before about 1980," since "before 1980" is 80% of the 20th century, and we are only 17% into the 21st century (17% of 100 yrs, a.k.a. a century, is 17 years)? [20% + 17% of 200 years (20th,21st centuries=200yrs), is only 37yrs out of 200 yrs. "tail wagging the dog?"]
IV. The World According To Measurements
Today's graphs (Fig. 1 through Fig. 4) use the latest WOD in situ data (measurements) as well as the latest TEOS scientific thermodynamic software library, as well as robust Dredd Blog software, to generate CSV files.
The graph at Fig. 1 shows PSMSL tide gauge station in situ (measurements on location) details of sea level change compared with in situ thermosteric volume change.
The tide gauge station records show a sea level rise trend, while the thermal
The graph at Fig. 2 shows TEOS absolute salinity compared to old-school salinity.
The graph at Fig. 3 shows TEOS conservative temperature compared to in situ temperature.
The graph at Fig. 4 shows in situ tide gauge records of sea level change compared to TEOS calculated thermosteric sea level change.
These graphs, together with the data they are based on, falsify the hypothesis that thermal expansion is "the" or even "a" major cause of sea level rise in the 20th and/or 21st centuries.
There may be an increase in information about this due to an interesting, recently filed lawsuit (Exxon, Shell and other carbon producers sued for sea level rises in California).
The next post in this series is here, the previous post in this series is here.