Observations and measurements show that crystals remain relatively compact at low ice supersaturations, but become increasingly hollowed and complex as the ice supersaturation rises. Prior measurements at temperatures >−25°C indicate that the transition from compact, solid ice to morphologically complex crystals occurs when the excess vapor density exceeds a threshold value of about 0.05 g m−3. A comparable threshold is not available at low temperatures. A temperature-dependent criterion for the excess vapor density threshold (Δ
- Award ID(s):
- 2128347
- PAR ID:
- 10432354
- Date Published:
- Journal Name:
- Journal of the Atmospheric Sciences
- Volume:
- 80
- Issue:
- 2
- ISSN:
- 0022-4928
- Page Range / eLocation ID:
- 501 to 517
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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