Friday, December 26, 2014

The Rich Get Richer

The Christmas storm was yet another where the rich (i.e., Little Cottonwood) just keep getting richer.  What kind of a Ponzi scheme is Mother Nature running this year?

As summarized by the National Weather Service, here are the snow totals for the storm so far showing very nicely the contrast from Little Cottonwood to Park City:

Snowbird: 24" (through 6 AM Friday)
Alta-Collins: 19" (4 AM Friday)
Alta UDOT: 15" (3 AM Friday)
Big Cottonwood Spruces: 12" (5 AM Friday)
Solitude: 9" (5 AM Friday)
Brighton Crest: 13" (7 AM Friday)
Canyons, 8800 ft: 12" (7 AM Friday)
Park City Summit: 6" (7 AM Friday)

Some of these numbers are real headscratchers for me.  Only 9" at Solitude and 6" at Park City Summit, but 12" at Canyons and 13" at Brighton?  I wish I planned on skiing today just to walk around the Park City Ridgeline to see what the heck is going on and whether or not these numbers are real or just an artifact of data representativeness. 

If we forget about that noise and instead concentrate on the signal, we see that this was yet another storm where Little Cottonwood cleaned up.  Snowfall totals are highest in Little Cottonwood and drop off as one moves to Big Cottonwood Canyon and then to the Park City side.  Although that's consistent with climatology, we've had several storms this year in which that signal has been highly amplified.  In other words, the contrast between Little Cottonwood and Park City has been larger than we might expect from climatology.  In other words, the rich get richer and the poor get poorer. 

This shows up fairly well in the SNOTEL data.  Through Christmas, Snowbird has a median snowpack snow water equivalent (SWE) of 10.7 inches.  However, it now sits at 14.1 inches, 132% of the median. 

Source: NWS
When we move into Big Cottonwood, the median snowpack SWE at Brighton drops to 8.0 inches, lower than Snowbird.  But while Snowbird is now above its long-term median, Brighton is just below its long-term median at 7.6 inches.  

Source: NWS
Finally, we jump across the Park City Ridgeline to the Thaynes Canyon SNOTEL.  Here the median is 7.8 inches, the lowest of the three sites.  The observed snowpack SWE is 7.0 inches, only 90% of median.  

Source: NWS
 There are no snowpack observations at low elevation on the Park City side, but I suspect this trend amplifies as you head further down the mountain as the snowpack in Park City is typically meager, but is especially so this year.

And here's another interesting thing that I hope someone skiing at Alta today can comment on.  We have an automated snow observing system operating in Albion Basin this year.  It measured about 3" of snow from 3 PM yesterday afternoon through this morning.  The Alta-Collins station got 8" in the same period.

Very interesting stuff. 

2 comments:

  1. It's also nice to see the lower elevation sites north of I-80 and in the Oquirrhs back above the median line. Snow depth is now greater at many of those sites than at Brighton, and snowfall probably rivaled the 24" at Snowbird base in many lower/mid elevation Oquirrh and Wasatch sites away from the Cottonwoods.

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  2. Hi Jim,

    Many of us believe that it snows more in Collins Gulch than it does in Albion Basin during a classic LCC storm. Ask Titus!

    -Chris in Alta

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