Project Ideas
Project COLDSTORM
The Convective Origins and Localized Dynamics of Snowfall Through, Observations, Research, and Modeling experiment (Project COLDSTORM) would seek to understand the complexities of convective snowfall events, which are marked by sudden changes in wind velocity and direction, as well as intense snowfall. These events are major hazards during winters due to their swift onset, high precipitation rates, and reduced visibility, prompting the National Weather Service to issue warnings. These convective snowfall phenomena are typically found in areas with lake effect snow, near cyclone cold fronts, and between the boundary of an extratropical cyclone’s dry slot and comma head region (where convective cells are ingested into the commahead region on the warm side). A notable challenge in predicting these events is the absence of a comprehensive observational network, especially in regions with insufficient radar coverage. There's a limited body of literature and data on these high-impact, cold-season convective events. COLDSTORM would employ aircraft, mobile radars, and surface instruments to gather detailed observational data. The primary objective would be to delve deep into the multi-scale processes affecting these events' predictability and variability. The study would address questions about the characteristics of different convective snowfall events, the thermodynamic environment's role in shaping these events, the multi-scale processes' contribution to their predictability, and entrainment's role in altering the convective environment.
SLOPE
In the 1980s, researchers conducted studies on wintertime orographic clouds over the San Juan Mountains. However, despite these efforts, there remain significant gaps in our understanding of their influence on local dynamics and microphysics. This is especially true for a mountain range with much higher and jagged terrain. The San Juan Mountains play a crucial role as a tributary to the Colorado River, supplying vital water resources to the broader Southwest region. The intricate relationship between atmospheric dynamics and cloud microphysics, particularly the feedback mechanisms connecting them, demands further exploration. Additionally, the effects of these microphysical properties on local weather patterns, especially precipitation, remain ambiguous. From a water resource standpoint, while we possess some understanding of how these dynamics affect snowpack accumulation and melt, the comprehensive effects of shifting climate conditions on these processes are still elusive. Considering these knowledge gaps, there's a pressing need for an extensive meteorological field study over the San Juan Mountains. This project could be called SLOPE or the Study of Localized Orographic Precipitation Enhancement and include airborne and ground based radars. Such a project would not only expand on recent findings from wintertime orographic field campaigns, like SNOWIE, but would offer invaluable insights for future water resource management in the region.
Atmospheric River Microphysics Project
Atmospheric rivers are a critical water resource to the western United States. Comparing their microphysical characteristics over the ocean and inland regions would be critical to understanding moisture flux into water starved regions of the intermountain Western United States. Field experiments studying atmospheric rivers have primarily targeted the Northeast Pacific. This region has a high frequency of landfalling extratropical cyclones, combined with strong orographic enhancement that help make high‐impact precipitation events. Several recent studies have measured the properties of ARs in that region including the California Land‐Falling Jets Experiment (CALJET), Pacific Land‐Falling Jets Experiment (PACJET), and California Water Service (CalWater), etc. These studies have primarily focused on obtaining dropsonde measurements to better understand the thermodynamic and kinematic structure of atmospheric rivers. Microphysical processes within atmospheric rivers have been interpreted primarily based on spaceborne and ground‐based vertically pointing radar analyses and/or surface‐based disdrometer measurements of drop size distribution. These studies together show that precipitation from landfalling northeast Pacific atmospheric rivers in mountainous regions can be characterized as a “seeder‐ feeder” process. Although significant progress has been made in interpreting microphysical processes from a remote sensing perspective, studies have not directly measured particle size distributions and habits through the depth of atmospheric rivers. I would like to help coordinate a large-scale field campaign effort that deploys rawinsondes and collects microphysical measurements across numerous heights in order to sample different particle growth layers and capture how bulk microphysical characteristics change with depth over the ocean and over the terrain within atmospheric rivers. Potential studies include comparing dynamical and microphysical processes within inland penetrating atmospheric river cloud cover with that sampled over ocean, looking at the large-scale and mesoscale dynamics within atmospheric rivers using airborne vertically pointing radar data, how bulk measured microphysical properties vary with depth within atmospheric rivers, how microphysical properties vary as a function of atmospheric river intensity (measured using IVT).
