Precipitation Efficiency by Storm Type in km-Scale Climate Simulations and Satellite Observations

Precipitation efficiency (PE), the fraction of cloud condensate converted into surface precipitation, is a key metric for understanding Earth's hydroclimate but has been challenging to observe and evaluate in models. Using satellite-retrieved ice water path (IWP) and precipitation estimates, we assess PE in a 4-km convection-permitting climate simulation across six North American storm types: small-scale, intermediate, and mesoscale convective systems, tropical cyclones, extratropical cyclones, and atmospheric rivers. The simulation reproduces observed PE characteristics and IWP-precipitation relationships across all storm types. The agreement between IWP-based and an alternative PE estimation method leveraging saturation adjustment is better for convective storms that produce a lot of cloud ice. PE varies by storm type, with tropical cyclones exhibiting the highest PE and least sample variability. PE also evolves over storm lifetimes, showing lower values during initiation and decay. Our results support the use of km-scale models for realistic PE analysis.