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Re: [pct-l] Snow, Fire, Griz, GPS

At 09:10 PM 3/27/98 -0800, Dave wrote:

>Well, OK ,except the big flood year began the same.   And the warm rains
>caused an early meltdown.  We will see.

You are mistaken about cause and effect here. Here is my post from a few
weeks back:

even if precipitation falls in the form of
rain it won't melt much snow. Rain adds some energy to the snow pack, but
overall the effect of rain on snow is negligible. For example, it takes 8
inches of rain at 50 degrees F to melt just 1 inch of snow (water
equivalent). According to Linacre (1992), factors for melting snow in order
of importance are: 1. direct solar radiation 2. warm wind (convection) 3.
condensation and rain. Studies in California show that in April and May the
net irradiance (direct solar radiation) is about 3 times the convective
energy flux (wind). What does this mean for snow melt in an el-nino year?
If solar radiation is reduced due to cloudy days etc. then the snow pack
will receive significantly less energy overall on a daily basis. The result
is that the snow pack will persist until it reaches a point where
additional energy actually melts the snow, which will be much later in the
spring.

Yeti

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Cc:            pct-l-digest@saffron.hack.net
From:          Jacob B Barowsky <fsjbb@aurora.alaska.edu>
Date:          Sat, 28 Mar 1998 16:03:06 -0900 (AKST)
Subject:       Re: [pct-l] Snow, Fire, Griz, GPS
Content-type:  TEXT/PLAIN; charset=US-ASCII

On Sat, 28 Mar 1998, mark dixon wrote:
 
> even if precipitation falls in the form of
> rain it won't melt much snow. Rain adds some energy to the snow pack, but
> overall the effect of rain on snow is negligible. For example, it takes 8
> inches of rain at 50 degrees F to melt just 1 inch of snow (water
> equivalent).  

If I understand you correctly this means 8" of rain will melt approximatly
10" of snow. Although rain may not be as effective at melting snow as
sunshine it is hardly negligable.

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