First point is true for glaciers. Neatly, the meltwater creates little
sinusoidal (right word? sine-generated) meander patterns on the ice, here
and there plunging in falls into caverns that shade through blue into
blackness. But not true in my experience with snowbanks during the
meltout. They drip. They absorb rain. Being isothermic, they discharge
water off the lower side of the snowbank. But water doesn't flow on them.
Second point is true.
Crispin wrote:
>There may be other factors. Unconsolidated snow is an extremely good
>insulator -- rain, by compacting the snow, may cause solar energy to
>be significantly more efficient at melting it.
True, and extra true because it lowers the albedo of the snowbanks. Snow
varies enormously in water content, down from Alta powder, which is 15 - 20
inches of snow per inch of water, to the state postulated above, where
rainwater has saturated the snowbanks until they begin to approach an inch
to inch correspondence of snow depth with snowwater depth.
Also, warm rain means
>warm air, and, while the specific heat of air is very low, there's
>lots of it -- the ratio of the volume of air to the volume of the
>rain is probably many thousands of times.
A good point. And there's no space in that moist air to take up snowwater
by sublimation -- a process not much considered, but which can rob a
winter's snowpack of much of its water in a week or so.
-- "But you and I, we've been through that...."
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