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Temperature, density, and pressure. This is mainly used to draw isopycnal
lines on TS diagrams, hence the dual meanings for salinity and temperature,
depending on the value of eos."><meta property="og:description" content="Compute Practical or Absolute Salinity, given in-situ or Conservative
Temperature, density, and pressure. This is mainly used to draw isopycnal
lines on TS diagrams, hence the dual meanings for salinity and temperature,
depending on the value of eos."></head><body>
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      <h1>Seawater Salinity From Temperature and Density</h1>
      <small class="dont-index">Source: <a href="https://github.com/dankelley/oce/blob/HEAD/R/sw.R" class="external-link"><code>R/sw.R</code></a></small>
      <div class="d-none name"><code>swSTrho.Rd</code></div>
    </div>

    <div class="ref-description section level2">
    <p>Compute Practical or Absolute Salinity, given in-situ or Conservative
Temperature, density, and pressure. This is mainly used to draw isopycnal
lines on TS diagrams, hence the dual meanings for salinity and temperature,
depending on the value of <code>eos</code>.</p>
    </div>

    <div class="section level2">
    <h2 id="ref-usage">Usage<a class="anchor" aria-label="anchor" href="#ref-usage"></a></h2>
    <div class="sourceCode"><pre class="sourceCode r"><code><span><span class="fu">swSTrho</span><span class="op">(</span></span>
<span>  <span class="va">temperature</span>,</span>
<span>  <span class="va">density</span>,</span>
<span>  <span class="va">pressure</span>,</span>
<span>  eos <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/options.html" class="external-link">getOption</a></span><span class="op">(</span><span class="st">"oceEOS"</span>, default <span class="op">=</span> <span class="st">"gsw"</span><span class="op">)</span></span>
<span><span class="op">)</span></span></code></pre></div>
    </div>

    <div class="section level2">
    <h2 id="arguments">Arguments<a class="anchor" aria-label="anchor" href="#arguments"></a></h2>


<dl><dt id="arg-temperature">temperature<a class="anchor" aria-label="anchor" href="#arg-temperature"></a></dt>
<dd><p><em>in-situ</em> temperature (\(^\circ\)C), defined
on the ITS-90 scale; see “Temperature units” in the documentation for
<code><a href="swRho.html">swRho()</a></code>.</p></dd>


<dt id="arg-density">density<a class="anchor" aria-label="anchor" href="#arg-density"></a></dt>
<dd><p><em>in-situ</em> density or sigma value (\(kg/m^3\))</p></dd>


<dt id="arg-pressure">pressure<a class="anchor" aria-label="anchor" href="#arg-pressure"></a></dt>
<dd><p><em>in-situ</em> pressure (dbar)</p></dd>


<dt id="arg-eos">eos<a class="anchor" aria-label="anchor" href="#arg-eos"></a></dt>
<dd><p>equation of state, either <code>"unesco"</code> (see references 1 and 2)
or <code>"gsw"</code> (see references 3 and 4).</p></dd>

</dl></div>
    <div class="section level2">
    <h2 id="value">Value<a class="anchor" aria-label="anchor" href="#value"></a></h2>
    <p>Practical Salinity, if <code>eos="unesco"</code>, or Absolute Salinity, if
<code>eos="gsw"</code>.</p>
    </div>
    <div class="section level2">
    <h2 id="details">Details<a class="anchor" aria-label="anchor" href="#details"></a></h2>
    <p>For <code>eos="unesco"</code>, finds the practical salinity that yields the given
density, with the given in-situ temperature and pressure.  The method is a
bisection search with a salinity tolerance of 0.001.  For <code>eos="gsw"</code>,
the function <code><a href="http://teos-10.github.io/GSW-R/reference/gsw_SA_from_rho.html" class="external-link">gsw::gsw_SA_from_rho()</a></code> in the <a href="https://CRAN.R-project.org/package=gsw" class="external-link"><span class="pkg">gsw</span></a>
package is used
to infer Absolute Salinity from Conservative Temperature.</p>
    </div>
    <div class="section level2">
    <h2 id="references">References<a class="anchor" aria-label="anchor" href="#references"></a></h2>

<ol><li><p>Fofonoff, P. and R. C. Millard Jr, 1983. Algorithms for computation of
fundamental properties of seawater. <em>Unesco Technical Papers in Marine
Science</em>, <em>44</em>, 53 pp</p></li>
<li><p>Gill, A.E., 1982. <em>Atmosphere-ocean Dynamics</em>, Academic Press, New
York, 662 pp.</p></li>
<li><p>IOC, SCOR, and IAPSO (2010). The international thermodynamic equation of
seawater-2010: Calculation and use of thermodynamic properties.  Technical
Report 56, Intergovernmental Oceanographic Commission, Manuals and Guide.</p></li>
<li><p>McDougall, T.J. and P.M. Barker, 2011: Getting started with TEOS-10 and
the Gibbs Seawater (GSW) Oceanographic Toolbox, 28pp., SCOR/IAPSO WG127,
ISBN 978-0-646-55621-5.</p></li>
</ol></div>
    <div class="section level2">
    <h2 id="see-also">See also<a class="anchor" aria-label="anchor" href="#see-also"></a></h2>
    <div class="dont-index"><p><code><a href="swTSrho.html">swTSrho()</a></code></p>
<p>Other functions that calculate seawater properties:
<code><a href="T68fromT90.html">T68fromT90</a>()</code>,
<code><a href="T90fromT48.html">T90fromT48</a>()</code>,
<code><a href="T90fromT68.html">T90fromT68</a>()</code>,
<code><a href="computableWaterProperties.html">computableWaterProperties</a>()</code>,
<code><a href="locationForGsw.html">locationForGsw</a>()</code>,
<code><a href="swAbsoluteSalinity.html">swAbsoluteSalinity</a>()</code>,
<code><a href="swAlpha.html">swAlpha</a>()</code>,
<code><a href="swAlphaOverBeta.html">swAlphaOverBeta</a>()</code>,
<code><a href="swBeta.html">swBeta</a>()</code>,
<code><a href="swCSTp.html">swCSTp</a>()</code>,
<code><a href="swConservativeTemperature.html">swConservativeTemperature</a>()</code>,
<code><a href="swDepth.html">swDepth</a>()</code>,
<code><a href="swDynamicHeight.html">swDynamicHeight</a>()</code>,
<code><a href="swLapseRate.html">swLapseRate</a>()</code>,
<code><a href="swN2.html">swN2</a>()</code>,
<code><a href="swPressure.html">swPressure</a>()</code>,
<code><a href="swRho.html">swRho</a>()</code>,
<code><a href="swRrho.html">swRrho</a>()</code>,
<code><a href="swSCTp.html">swSCTp</a>()</code>,
<code><a href="swSR.html">swSR</a>()</code>,
<code><a href="swSigma.html">swSigma</a>()</code>,
<code><a href="swSigma0.html">swSigma0</a>()</code>,
<code><a href="swSigma1.html">swSigma1</a>()</code>,
<code><a href="swSigma2.html">swSigma2</a>()</code>,
<code><a href="swSigma3.html">swSigma3</a>()</code>,
<code><a href="swSigma4.html">swSigma4</a>()</code>,
<code><a href="swSigmaT.html">swSigmaT</a>()</code>,
<code><a href="swSigmaTheta.html">swSigmaTheta</a>()</code>,
<code><a href="swSoundAbsorption.html">swSoundAbsorption</a>()</code>,
<code><a href="swSoundSpeed.html">swSoundSpeed</a>()</code>,
<code><a href="swSpecificHeat.html">swSpecificHeat</a>()</code>,
<code><a href="swSpice.html">swSpice</a>()</code>,
<code><a href="swSpiciness0.html">swSpiciness0</a>()</code>,
<code><a href="swSpiciness1.html">swSpiciness1</a>()</code>,
<code><a href="swSpiciness2.html">swSpiciness2</a>()</code>,
<code><a href="swSstar.html">swSstar</a>()</code>,
<code><a href="swTFreeze.html">swTFreeze</a>()</code>,
<code><a href="swTSrho.html">swTSrho</a>()</code>,
<code><a href="swThermalConductivity.html">swThermalConductivity</a>()</code>,
<code><a href="swTheta.html">swTheta</a>()</code>,
<code><a href="swViscosity.html">swViscosity</a>()</code>,
<code><a href="swZ.html">swZ</a>()</code></p></div>
    </div>
    <div class="section level2">
    <h2 id="author">Author<a class="anchor" aria-label="anchor" href="#author"></a></h2>
    <p>Dan Kelley</p>
    </div>

    <div class="section level2">
    <h2 id="ref-examples">Examples<a class="anchor" aria-label="anchor" href="#ref-examples"></a></h2>
    <div class="sourceCode"><pre class="sourceCode r"><code><span class="r-in"><span><span class="fu">swSTrho</span><span class="op">(</span><span class="fl">10</span>, <span class="fl">22</span>, <span class="fl">0</span>, eos <span class="op">=</span> <span class="st">"gsw"</span><span class="op">)</span> <span class="co"># 28.76285</span></span></span>
<span class="r-out co"><span class="r-pr">#&gt;</span> [1] 28.76249</span>
<span class="r-in"><span><span class="fu">swSTrho</span><span class="op">(</span><span class="fl">10</span>, <span class="fl">22</span>, <span class="fl">0</span>, eos <span class="op">=</span> <span class="st">"unesco"</span><span class="op">)</span> <span class="co"># 28.651625</span></span></span>
<span class="r-out co"><span class="r-pr">#&gt;</span> [1] 28.65163</span>
<span class="r-in"><span></span></span>
</code></pre></div>
    </div>
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