Examining the impacts of model resolution on convective cloud structure and characteristics

During my postdoc at the National Center for Atmospheric Research, Dr. Hugh Morrison and I came across a potential way to better examine the impacts of model resolution on convective clouds, specifically focusing on changes in updraft characteristics. After nearly 3 years, the work was finally completed and published (Lebo and Morrison 2015). The key difference to this approach is that we do not initiate the model with different resolutions; instead, we run the model with a typical resolution, output the fields, interpolate to a higher resolution, and restart the model with the fully developed fields but at a higher resolution. It turns out that this largely reduces the computational expense and provides a systematic way to examine the effects of resolution because all of the simulates begin with the same mature cloud field. Using this approach, we found that an optimal resolution of no more than 250 m is necessary for convective cloud systems (at least for continental squall lines). Future efforts are going to be focused on understanding the effects on downdrafts and entrainment using this new approach.