Thin boundary layer Arctic mixed-phase clouds are generally thought to precipitate pristine and aggregate ice crystals. Here we present automated surface photographic measurements showing that only 35\% of precipitation particles exhibit negligible riming and that graupel particles $\geq1\,\rm{mm}$ in diameter commonly fall from clouds with liquid water paths less than $50\,\rm{g\,m^{-2}}$. A simple analytical formulation predicts that significant riming enhancement can occur in updrafts with speeds typical of Arctic clouds, and observations show that such conditions are favored by weak temperature inversions and strong radiative cooling at cloud top. However, numerical simulations suggest that a mean updraft speed of $0.75\,\rm{m\,s^{-1}}$ would need to be sustained for over one hour. Graupel can efficiently remove moisture and aerosols from the boundary layer. The causes and impacts of Arctic riming enhancement remain to be determined.

Last modified

• 10/25/2024

Creator

• Garrett, Timothy J.
• Fitch, Kyle E.

Contributors

• Shkurko, Konstantin
• Talaei, Ahmad
• Gaustad, Krista
• Maahn, Maximilian

Subject

• Atmospheric sciences
• Computational research
• Arctic research

Language

• English

Identifier

• https://doi.org/10.7278/s50dva5jk2pd

Keyword

• computational research
• radiative transfer
• microwave radiometer
• liquid water path
• graupel
• Alaska
• atmospheric radiation measurement
• water vaper
• atmospheric sciences
• arctic

Date created

• Code creation: 2016-12-08 to 2018-06-09
• Processed: 2017-06-27
• Processed: 2019-03-20

Location

• Oliktok Point, Alaska, United States

Resource type

• Software or Program Code
• Dataset

Source

• NASA

License

• CC BY NC - Allows others to use and share your data non-commercially and with attribution.