br.big fix

UPDATED CSS:
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UPDATED HTML:
<div style="max-width:41em;">

<ul style="margin-left:0.2em;padding-left:0.2em">

  <li id="negative" style="margin-top:1em;margin-bottom:0.75em"><b>Negative (stabilizing/attenuating) feedbacks:</b>

    <ol style="margin-top:0.5em">

      <li id="planck">
        <p>Planck Feedback. The most fundamental feedback effect is simply that when the Earth's surface gets warmer, it loses heat faster, thereby reducing the increase in temperature.</p>
        <p><i>&ldquo;It is like pumping air into a tyre with a puncture: the harder you pump the faster the air escapes.&rdquo;</i>&nbsp;&ndash;<a href="http://archive.is/nUwyk#selection-227.166-227.265">Clive Best</a></p>

        <p>The simplest and easiest to quantify component of that effect is the radiative component,
        called &ldquo;Planck feedback.&rdquo; Radiative emissions from a warm body are
        <a href="http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/stefan.html">proportional to</a>
        the 4<sup>th</sup> power of the body's absolute temperature (temperature in Kelvin), according to the Stefan-Boltzmann law:</p>

        <p><span class=feedbackpath><b>E = &epsi; &sigma; T<sup>4</sup></b></span></p>
        <p>where:</p>
        <p><span class=feedbackpath>epsilon <b>&epsi;</b> is emissivity, [0..1] (function of frequency, unless perfect grey-body)<br>
          sigma <b>&sigma;</b> is the Stefan-Boltzmann constant, 5.670374419E-8 W/m<sup>2</sup>K<sup>4</sup><br>
          temperature <b>T</b> is in Kelvin<br>
          <b>E</b> = radiative emission in W/m<sup>2</sup>
          </span></p>

        <p>It is calculated that a uniform global temperature increase of
        1&deg;C would increase radiant heat loss from the surface of the Earth by about 1.4% (variously estimated to be 3.1 to <nobr>3.7 W/m&sup2;,</nobr> or <a href="AR5_Table_9.5_p.818.html#:~:text=Planck_fdbk">3.1 to 3.3 W/m&sup2; in the CMIP5 models</a>,
        or <a href="https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter07.pdf#page=46">3.0 to 3.4 W/m&sup2; in AR6 &sect;7.4.2.1</a>
          &mdash; it's <a href="Cronin2020_PlanckQJ.pdf">complicated</a>).</p>

         <p><span class=feedbackpath>warmer&nbsp;surface &rarr;&nbsp;more&nbsp;rapid&nbsp;radiative&nbsp;heat&nbsp;loss &rarr;&nbsp;cooler&nbsp;surface</span></p>

        <p>However, <a href="Koll2018_pnas.1809868115.pdf">Koll &amp; Cronin (2018)</a> report that...</p>
      </li>

      <li>(Another list element)</li>

    </ol>


  <li id="positive" style="margin-top:1em;margin-bottom:0.75em"><b>Positive (amplifying) feedbacks:</b></li>

</ul>

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