<p>The heat content of a substance is known as <a href="http://en.wikipedia.org/wiki/Enthalpy" rel="nofollow">enthalpy</a>.  The international convention used for the <a href="http://www.teos-10.org/" rel="nofollow">Thermodynamic Equation of Sea Water</a> is maintained by the Joint Committee on the Properties of Seawater. </p>

<p>Equations for calculating the thermodynamic variables of sea water, humid air and other substances are set forth in <a href="http://www.teos-10.org/pubs/SIA_Paper_1.pdf" rel="nofollow"><strong>the Numerical implementation and oceanographic application of the thermodynamic potentials of liquid water, water vapour, ice, seawater and humid air – Part 1: Background and equations</strong></a> by R. Feistel, D. G. Wright,†, D. R. Jackett, K. Miyagawa, J. H. Reissmann, W. Wagner, U. Overhoff, C. Guder
,A. Feistel, and G. M. Marion. <em>Enthalpy of sea water is discussed in section 4.3.</em>   </p>

<p>One would need temperature, pressure and salinity information for each point in the ocean, and integrate specific enthalpy over the entire volume of the ocean. </p>

CC BY-SA 3.0
2014-04-24T20:52:17.297Z
2015-12-12T12:24:54.263Z
2015-12-12T12:24:54.263Z
DavePhD
<p>Potential enthalpy is the better variable. TEOS-10 functions render the main work as doing the <em>in situ</em> measurements. Fortunately, a great amount of that has already been done (<a href="https://blogdredd.blogspot.com/2018/11/in-search-of-ocean-heat.html" rel="nofollow noreferrer">In Search of Ocean Heat</a>).</p>

<p>One converts practical salinity or conductivity into Absolute Salinity, converts temperature into Conservative Temperature, and height (-depth) into Pressure.</p>

<p>Then the TEOS-10 functions can be used with those variables to calculate the requisite forms of enthalpy (specific enthalpy, dynamic enthalpy, potential enthalpy).</p>

CC BY-SA 4.0
2018-11-25T14:01:35.647Z
2018-11-25T14:01:35.647Z
Dredd
<p>This is similar to <a href="https://earthscience.stackexchange.com/questions/16/how-is-ocean-heat-uptake-measured">How is ocean heat content measured?</a>, but here I'm thinking about the total content rather than fluxes in the content between land and ocean.</p>

CC BY-SA 4.0
2022-02-12T11:29:02.130Z
7 years on. I've been attempting to determine this. I used Water at 0C as a reference. Ocean volume is about 3.3E8 cubic miles. Means depth is 3660 m. Temperature of top 200 metres varies from 0-30C with 20C as a rough mean. (This does not make a vast difference). Balance mean is about 4 degrees C. Mean of both layers is about 4.9C - say 5C. Convert to cc ( :-) ) and ue say 4.2 J/cc/K energy gives ~~~~= 2.5 x 10^28 Joule. | All ocean heating since 1970 is typically gives as about 20 x 10^22 Joule so 50 year heating is about 0.001% for whole period.  E&OE :-)
Russell McMahon
<atmosphere><ocean>
How do we measure the total heat content contained in ocean and atmosphere?
InquilineKea
# How do we measure the total heat content contained in ocean and atmosphere?

(Asked by: username_0 on 2014-04-15)

This is similar to [How is ocean heat content measured?](https://earthscience.stackexchange.com/questions/16/how-is-ocean-heat-uptake-measured), but here I'm thinking about the total content rather than fluxes in the content between land and ocean.

**Tags:** atmosphere, ocean

> **Comments:**
> **username_1**: 7 years on. I've been attempting to determine this. I used Water at 0C as a reference. Ocean volume is about 3.3E8 cubic miles. Means depth is 3660 m. Temperature of top 200 metres varies from 0-30C with 20C as a rough mean. (This does not make a vast difference). Balance mean is about 4 degrees C. Mean of both layers is about 4.9C - say 5C. Convert to cc ( :-) ) and ue say 4.2 J/cc/K energy gives ~~~~= 2.5 x 10^28 Joule. | All ocean heating since 1970 is typically gives as about 20 x 10^22 Joule so 50 year heating is about 0.001% for whole period.  E&OE :-)  

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## 2 answers

### Answer by username_2 on 2014-04-24. Score: 10

The heat content of a substance is known as [enthalpy](http://en.wikipedia.org/wiki/Enthalpy). The international convention used for the [Thermodynamic Equation of Sea Water](http://www.teos-10.org/) is maintained by the Joint Committee on the Properties of Seawater.

Equations for calculating the thermodynamic variables of sea water, humid air and other substances are set forth in [**the Numerical implementation and oceanographic application of the thermodynamic potentials of liquid water, water vapour, ice, seawater and humid air – Part 1: Background and equations**](http://www.teos-10.org/pubs/SIA_Paper_1.pdf) by R. Feistel, D. G. Wright,†, D. R. Jackett, K. Miyagawa, J. H. Reissmann, W. Wagner, U. Overhoff, C. Guder
,A. Feistel, and G. M. Marion. *Enthalpy of sea water is discussed in section 4.3.*

One would need temperature, pressure and salinity information for each point in the ocean, and integrate specific enthalpy over the entire volume of the ocean.


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### Answer by username_3 on 2018-11-25. Score: 2

Potential enthalpy is the better variable. TEOS-10 functions render the main work as doing the *in situ* measurements. Fortunately, a great amount of that has already been done ([In Search of Ocean Heat](https://blogdredd.blogspot.com/2018/11/in-search-of-ocean-heat.html)).

One converts practical salinity or conductivity into Absolute Salinity, converts temperature into Conservative Temperature, and height (-depth) into Pressure.

Then the TEOS-10 functions can be used with those variables to calculate the requisite forms of enthalpy (specific enthalpy, dynamic enthalpy, potential enthalpy).


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