Implications of Precipitation Particle Properties for Improved
Understanding of Ice-Nucleating Particles in West Texas
Abstract
This study was conducted to assess precipitation particle properties,
including ice-nucleating particle (INP) concentration (L^-1 Air), in
West Texas, where the semi-arid climate prevails and typically
<40 inches of rainfall coincides per year. Further, the West
Texas region is dominated by deep convective clouds, where INPs play a
crucial role in hailstorm and thunderstorm processes (e.g., Li et al.,
2017; Rosenfeld et al., 2008). In this study, we looked into major
precipitation events observed throughout the year in 2018 and 2019 in
the Texas Panhandle area. More specifically, to characterize immersion
freezing efficiency (T > -25 degree C) of our precipitation
samples, we used a cold-stage instrument called West Texas Cryogenic
Refrigerator Applied to freezing Test (WT-CRAFT) system (Hiranuma et
al., 2019). Additionally, a disdrometer is used to look into the
relationship between INP concentration, intensity and size of
precipitation particles. An indigenously developed Internet of Things
(IoT) air quality sensors were also used to compare ambient air quality
(i.e., particulate matter concentrations) and meteorological conditions
to the measured INP concentrations. Overall, the study’s preliminary
results show a reasonable correlation between INP concentration and
precipitation properties (i.e., intensity). We also find a high ice
nucleation efficiency at higher temperatures (i.e., T > -15
degree C), which can be attributed to the biological INPs from local
agricultural sources. The results also suggest that INPs play an
important role in the precipitation particle size. These findings may be
important in artificially varying the severity of the precipitation by
varying the INP concentration in the West Texas region.