Most of the following was written early Saturday morning,
February 7th…
With fresh snow outside, one might think the sound that I
hear on the rooftop might be reindeer hooves, however it is the sound of wet
snow falling from the trees. So far this storm has brought us high winds, wildfires,
finally snow, and now rain.
Friday evening, Feb. 6 at 9:14 pm (weather report from the top of Mammoth Mountain)
Winds have decreased significantly since last night, but it’s still quite
breezy out there. I get so excited with major storm events. It brings people
together. I woke up one morning in northern Minnesota to 3+ feet of snow
burying my car. People were walking to the grocery store with sleds to carry
the food back home. Everyone just came together to help each other out. Storms
test our strength, our ability to adapt, resiliency to come back. I feel secure
knowing that I have the options of walking to work, taking the bus, and a
closet full of clothes to trudge through the snow (as was the case Saturday
morning) or to bow my head against the rain (as was the case Sunday night).
Although exciting, extreme weather events will unfortunately
become more common as the earth’s climate continues to change. Small shifts inthe average distribution of temperatures, precipitation and other climatevariables can substantially change the frequency and intensity of extreme events. From this recent storm event came tragedy: overturned trucks on the
highways (wind), cars in ditches (snow/ice), and communities evacuated (fire). And
the next thing to watch out for: avalanches.
At the Welcome Center we were lucky to hear a presentation
on avalanches from Sue Burak with the Inyo National Forest. Biggest take away
that I learned: Wind loading = avalanches.
What is wind loading?
Wind will bring snow from the windward (upward) side of
obstacles (ex: a ridge), and deposit the same snow on the leeward (downwind)
side.
Wind can deposit
snow 10 times more rapidly than snow falling from the sky. Also, wind-drifted
snow when it comes to a rest is often much denser than other non-wind loaded
snow, due to being ground up as it bounces along the ground. Ergo: wind loading
adds a significant amount of weight on top of other buried snow layers, and
forms a slab that can fracture quite easily. (info from the National Avalanche Center)
After storm events, Sue will go out and dig snow pits to
test the stability of the snow, and write a “Snowpack Summary” that is shared publicly.
A snowpit is dug vertically into the snowpack in order to observe the varying
snow layers and potentially perform stability tests, such as the compression
test (Isolate a column of snow, lay the blade of the shovel flat on top, begin
tapping progressively harder on the shovel blade until the column fails).
All of humanity will want to get out and enjoy this snow,
the first since Christmas time, but will their avalanche beacons be charged? Will
everyone know how to use them? Turn them on? Locate their buried friends? Will
people dig proper snow pits to check for avalanche danger?
The following story is a few years old, and it’s quite
lengthy, but if you have time to spare, it shares a story of an avalanche in
Washington in a way that demands respect for Mother Nature.
Social dynamics within a large group… I experienced that
while climbing the Middle Teton in Grand Canyon National Park in a group of
six. (Hail, thunder, etc…) Bad decisions are too often made. I’m lucky that all
in our group returned safely.
So back to avalanches, to ensure the safety of skiers,
snowboards and other snow enthusiasts, the Ski Patrol at Mammoth Mountain acts
as the towns rooster, waking everyone up at 6:30 am with the sounds of a WWII Howitzer,
intentionally triggering avalanches in the early morning when the mountain is
still closed (more on the howitzer here)
Now if only California would receive a few extreme snow fall
events (instead of extreme drought and unusually high temperatures)…
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