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

• 07/21/2020

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

Date created

• Code creation dates from 20161208 to 20180609
• Processed between 20170627 and 20190320

Location

• Oliktok Point, Alaska, United States

Related url

• See readme files

Resource type

• Software or Program Code
• Dataset