As we stand out in the smoking area here in Minnesota, we ponder the
deeper meaning of life. Todays question that came up has to do with
snow fall and the way it is accumulating on the vehicles in the
parking lot. Here is the scenario:

The wind is coming from the east so the snow is falling from the east
to the west. However the wetern side of the cars in the lot are being
covered with snow. We would expect the snow to accumulate on the
eastern side of the vehicles (impact side), but it isn't. One thought
was that due to the way the parking lot is setup that the cars next to
each other (in an east/west row) could cause the snow to be blocked by
the car next to it, but every car in the row has snow on the western
side.

My guess is it has to do with something like Bernoullis principle with
the wind creating a low pressure area as it moves over the eastern
side of the car and roof causing the snow to drop off as it passes
over, and accumulate on the opposite side of the vehicle.

Am I close, or have been standing out in the cold too long???

An answer should have a brief explanation about the physics behind
what's going on. (Don't make it too technical, I've already got brain
freeze from going outside to smoke so often) :-)

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Clarification of Question by cvenom-ga on 21 Jan 2005 12:09 PST

Pink,
Thanks for the quick response, but I got lost in that description
somewhere between "Introduction" and "References". (Classic line from
"A Fish Called Wanda" What was that middle part???) It was to
technical for me to understand. Thanks for the effort.

Hi cvenom....

I'm not a Researcher and I don't know the answer to your interesting question.
Just wanted to pop in and say I can really empathize with you for
smoking out in the bitter cold. Its freezing here where I am ( ON
Canada ) and we have the outside *smoker's ponderings* too. Good luck
with your question!

Steph53

This may be a bit on the "too technical" side, but it's worth a look:

http://www.eecs.berkeley.edu/~job/Papers/feldman-2002-MAW.pdf

Steph,
Non-smokers just don't realize how many solutions to the worlds
problems are solved in the smoking area. Remeber to layer-up before
venturing out!

How refreshing, Steph (and cvenom) smokes. Trust she likes a malt too.

You may be partly correct with Bernoulli, but another factor will be
the ?quality? of the snow. Here on the West Coast of Scotland, snow
usually lies on the facing side as it tends to be wet, especially if
there is a wind behind it. So it sticks to whatever it hits. Lighter,
whirly snow, will tend to lie in wind shadow areas, bit like fallen
leaves.

Nice to see that the University of California has put its expensive
finite element analysis software to good use. No mention of different
snow types in the paper so I guess snow has been standardised.

Best

Here's a link that discusses snow-fences:
http://www.agf.gov.bc.ca/resmgmt/publist/300series/307230-1.pdf

It suggests that solid objects should collect snow on both sides, but
perhaps cars don't because the wind can go underneath as well as over
top, keeping the windward side clear until hitting the turbulence on
the other side.

Having spent many winters in various parts of Ontario I can attest to
the efficacy of these fences. When I was but a lad, we moved to a
house in the country and were told by neighbours that we would have to
put up snow-fencing to have any hope of being able to keep the
driveway passable. The first year, we put the fencing up to block the
wind and keep the snow on the other (windward) side of the fence. We
quickly discovered the fallacy of this thinking, as huge drifts built
up across the driveway on the leeward side of the fence. Thank heavens
for kind neighbours with tractors!