servations</a></li>
<li class="toc-h3 nav-item toc-entry"><a class="reference internal nav-link" href="#Annualize-the-observation-fields">Annualize the observation fields</a></li>
<li class="toc-h3 nav-item toc-entry"><a class="reference internal nav-link" href="#Regrid-the-observation-fields">Regrid the observation fields</a></li>
<li class="toc-h3 nav-item toc-entry"><a class="reference internal nav-link" href="#Crop-the-observations-fields-to-make-the-problem-size-smaller">Crop the observations fields to