Observing and Characterizing High-Latitude Precipitation Processes: Perspectives From Space and Ground

October 31, 2024

Claire Pettersen

Hosted by Sue van den Heever

Abstract

High-latitude precipitation has widespread impacts on communities through regional ecology, hydrological planning, and socioeconomic effects. Accurate forecasts or projections of precipitation accumulation in numerical weather prediction or climate models are challenging due to uncertainties in parameterizations of cloud and precipitation processes. In this presentation, I feature recent findings from regime-based studies leveraging precipitation observations from both spaceborne platforms and ground-based instrument suites in high-latitude regions. Multi-instrument observations of clouds and precipitation can help better constrain processes in models and refine retrieval assumptions, leading to more accurate quantification of accumulation. I will highlight the advantage of long-term observations to examine key physical and dynamical precipitation processes through the lens of regime partitioning. Regimes are determined through distinct large-scale environmental conditions and precipitation properties and processes are investigated using remotely-sensed observations. Key findings demonstrate that regime-dependent characteristics show differences in precipitation frequency and location of occurrence, intensity, phase, and microphysical properties. Precipitation regimes are linked to significant seasonal and subseasonal, synoptic, and thermodynamic conditions such as atmospheric blocking, poleward moisture transport (e.g., atmospheric rivers), and cold-air outbreaks.