Update on CROCODILE/ The controversial role of convective precipitation in tropical variabilities

In this talk we'll provide updates on regional Earth system modeling capabilities within CESM as part of the CROCODILE project. We will demo new integrated tools for rapid grid and forcing generation as well as CESM case setup. We would appreciate feedback on how to build community around these tools as well as ways that we can collaborate to include more CESM components!

The convectively coupled equatorial waves (CCEWs) play important roles in regulating the weather and climate systems around the globe. The convective processes, which are typically parameterized in these models, are essential to their simulation and prediction. We assessed the contribution of convective precipitation to the total precipitation rate related to CCEWs in three reanalysis datasets including ERA5, JRA- 3Q, and MERRA2, as well as in some selected CMIP6 models. Preliminary results show a large uncertainty in the convective precipitation contribution to CCEWs. For Madden-Julian Oscillation (MJO), the leading subseasonal variation in the tropical atmosphere, both ERA5 and MERRA2 exhibit a transition from domination by convective precipitation to a more dependence on large-scale precipitation in its lifespan. However, such transition is not seen in JRA-3Q and the selected CMIP6 models. As the large uncertainty in the reanalysis datasets prohibits solid conclusions from the analysis, in-situ or satellite observations are needed in our future work to validate the findings.