Repurposing weather modification for cloud research showcased by ice crystal growth

Area of Science:

• Atmospheric Science
• Cloud Physics
• Weather Modification

Background:

• Accurate modeling of cloud processes is crucial for weather forecasting and climate projections, yet it remains a significant source of uncertainty.
• Laboratory studies of cloud processes are limited by their inability to replicate the complex conditions found in natural cloud systems.

Purpose of the Study:

• To investigate ice crystal growth rates in natural supercooled stratus clouds using glaciogenic cloud seeding.
• To bridge the gap between controlled laboratory experiments and complex natural cloud environments.

Main Methods:

• Conducted cloud seeding experiments in supercooled stratus clouds using an uncrewed aerial vehicle.
• Measured ice crystal growth rates 4-10 minutes downwind using in situ and ground-based remote sensing.

Main Results:

• Observed substantial variability in ice crystal growth rates, linked to variations in ice crystal number concentrations and supersaturation.
• Found nearly linear ice crystal population growth between 6 and 10 minutes for experiments at -15°C.
• Results suggest faster precipitation initiation than previously estimated due to high supersaturation in natural clouds.

Conclusions:

• Glaciogenic cloud seeding can be a valuable tool for fundamental cloud research, including ice growth and aerosol-cloud interactions.
• Findings contribute to improved cloud microphysics parameterizations for weather and climate models.
• This research advances the understanding needed for more accurate weather forecasts and climate projections.