 water_depth and  particle age.</p>
<section id="decaying-particle">
<h2>Decaying particle<a class="headerlink" href="#decaying-particle" title="Link to this heading">¶</a></h2>
<center>
  <video width="95%" controls muted autoplay loop src="../../_static/demos/demo60_SCHISM_3D_decaying_particle.mp4">
 </video>
</center><p>Decaying particle property used to size and colour  particles. <code class="docutils literal notranslate"><span class="pre">decay_time_scale</span></code> parameter = 3.5 hours.</p>
<ul 