Orographic Rainfall

This research area focuses on identifying and synthesizing the common atmospheric and topographic ingredients that create environments conducive to heavy orographic rainfall in varied settings such as the U.S Rockies, European Alps, East Asia, India, Taiwan, and New Zealand. Understanding these shared synoptic and mesoscale conditions is crucial for improving quantitative precipitation forecasting and flood risk mitigation in complex terrain.

This theme centers on empirical characterization and improvement of precipitation measurement accuracy in mountainous terrain, emphasizing microphysical rain properties, disdrometer observations, and weather radar QPE algorithms. It analyses challenges introduced by dropsize distributions, vertical variability in rain microphysics, beam blockage, and complex terrain effects which impact remote sensing precipitation retrievals. Accurate characterization of these factors is essential for enhancing radar precipitation estimates and hydrological forecasting in orographically complex regions.

This research area examines the integration of high-resolution regional climate and weather models with orographic drag parameterizations and multi-scale terrain representation to reduce precipitation simulation biases in steep mountainous regions. It emphasizes how realistic depiction of mesoscale and sub-grid scale terrain features and atmospheric flow orographic interactions improve moisture transport, convective triggering, and precipitation distributions. These advances are pivotal for accurate forecasting and climate analyses in complex topographic domains.