Evaluating the Diurnal and Semidiurnal Cycle of Precipitation in CMIP6 Models Using Satellite- and Ground-Based Observations
The results highlight the improvement in the diurnal cycle of precipitation in CMIP6 models compared to their CMIP5counterparts, which can be attributed to the use of more sophisticated convective parameterizations.
Model simulated diurnal cycle of precipitation is compared to two ground-based (ARM) and three satellite-based rainfall products. We also quantify an encouraging consistency between the satellite- and ground-based precipitation measurements despite differing spatiotemporal resolutions and sampling periods, which provides confidence in using them to evaluate the diurnal and semidiurnal cycle of precipitation in climate models.
The diurnal and semidiurnal cycle of precipitation simulated from CMIP6 models are evaluated globally between 60°S and 60°N as well as at 10 selected locations representing three categories of diurnal cycle of precipitation: 1) afternoon precipitation over land, 2) early morning precipitation over ocean, and 3) nocturnal precipitation over land. Several CMIP6 models have shown a significant improvement in the diurnal cycle of precipitation compared to their CMIP5 counterparts, notably in delaying afternoon precipitation over land. We also quantify an encouraging consistency between the satellite- and ground-based precipitation measurements, which provides confidence in using them to evaluate the diurnal and semidiurnal cycle of precipitation in climate models.