A few years ago another question touched on the relative rates of sublimation versus melting in terms of snow and snow pack disappearance.

What was unusual about the answer is the huge range of variability in the results from different studies. One study claiming only 2% of ablation was due to sublimation and another claiming almost all of it was. I vaguely remember an extensive New Zealand study (not shown in the answer) that had a result showing about half of ablation is due to irradiation (sublimation).

Has this subject been revisited by more thorough-going studies that answer the question definitively?

In my own view, it would seem that "backyard" experiments could be done on snow drifts to answer this question. In my mind there should be no one single numeric answer but rather a table which relates several factors:

  • the underlying ground material and strata (sandy soil, rock, asphalt, etc)
  • the air temperature
  • the latitude and time (= inclination to the sun)
  • surface area exposed to sun
  • surface area exposed to ground
  • volume of frozen accumulation
  • type of frozen accumulation (dry snow, wet snow, ice)

Based on these factors it should be possible using the principles of thermodynamics and physical experiments to create tables (or equations) that define ablation in terms of these seven variables.

Has any study been done to do this computation?

  • $\begingroup$ I'm not surprised by the variability in numbers. In the paper you cite, the author explains how, the records from November and February show that sublimation is a somewhat episodic phenomenon. Ranging from below 0.05 mm/hr for several days to short `sublimation events' during which sublimation rates remain greater than 0.02 mm/hr for longer than 24 hours. These sublimation events are a result of Chinook conditions which are typified by warm, dry downslope winds and are common in the Colorado Front Range, particularly in fall. It would seem that sublimation rates are very location-specific... $\endgroup$ Mar 18 '17 at 19:26
  • $\begingroup$ ...and likely inconsistent over the long haul. There are certainly involved equations that already model sublimation of ice vs. solar radiation (see p.47 of Physical Properties of Snow inscc.utah.edu/~campbell/snowdynamics/reading/Pomeroy.pdf for a few basic constants). The problem with a chart or table, is that it's only good for a snapshot in time. A good corollary is a Windchill table: it might be good for telling you what the temperature "feels" like but says nothing about heat loss from a small Norwegian with a fast metabolism vs. a large Indian with a very low metabolism... $\endgroup$ Mar 18 '17 at 19:44
  • $\begingroup$ ....all this to say that for a given snow pack, you'd need the entire snow year's meteorological record to put a number on total loss due to sublimation. And even that number couldn't be extrapolated to a snow pack in another part of the same mountain range, or even a different slope on the same mountain. $\endgroup$ Mar 18 '17 at 19:52

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