The Ski Area Snow Report: Fact or Fiction?

We’ve all had those days: The snow report is claiming an epic dump, but on the hill, it skis like only a few inches. What the heck? Is the snow report just a total lie? A publication in the American Economic Journal: Applied Economics decided to have a closer look.

Snow reporting is a challenging process. Things like elevation, wind, and aspect can cause the snow depth to vary significantly from one spot to another. Just because the snow stake is reading 12″ doesn’t mean there’s a foot evenly coating every part of the mountain. Even two snow stakes only a few feet apart can have different measurements. Some resorts, though, have gotten reputations for skewing the numbers regularly. Jonathan Zinman and Eric Zitzewitz from the Dartmouth College Department of Economics dug deeper into the data to see if this is genuinely deceptive advertising.

Zinman and Zitzewitz started their work by estimating resorts were exaggerating snowfall by 12-23% over government data sources.  Given that an independent data source may not be capturing the same snowfall as a resort microclimate, they hypothesized that within an individual resort’s reporting, new snow measurements would be greater on the weekends when potential skier traffic and revenue is the highest. They also looked at how terrain, resort competition, money back guarantees, and local population sizes affected reported snowfall.

Resort snowfall data was compiled for the winters of 2004-2005 through 2007-2008. Government snowfall data was captured for the same period using NOAA weather stations and the Snow Data Assimilation System (SNODAS), which provides high-tech snowfall estimates for a given area. To arrive at their conclusions, the two economists dove into some very heavy statistics work (that you can read about on your own).

The data suggest that on an average winter day, resorts are reporting 1.40 inches of new snow versus 1.22 inches recorded by SNODAS or 1.08 inches from NOAA/NOHRSC. This discrepancy is driven by resorts over-reporting on big powder days with eight or more inches of new snow.  Still, it’s a relatively small difference that could easily be accounted for by a resort microclimate and not deceptive advertising.

The two analyzed snowfall trends over the week to remove this direct comparison between resort and government snow data. While government snowfall data remained relatively flat, resorts reported the most snow on Saturdays, Sundays, and Mondays. On average, resorts reported about 0.5″ of extra snow on the weekends due to rounding up of measurements and exaggerating large storms. Half an inch doesn’t sound like much, but the inflated numbers were concentrated to only 30% of sampled days. This means many resorts are reporting accurately while others are stretching the truth. A more complex analysis suggests that when resorts do exaggerate, it’s by an inch or more. Even though Ullr doesn’t care that you only get to ski on the weekends, resorts have taken notice.

The “weekend effect” was seen to be slightly amplified by resorts with more expert terrain and those without money-back guarantees. The data showed an additional 0.14″ new snow was likely to be reported at such ski areas. As one would suspect, the price of exaggeration is much higher when you’re backing conditions with a guarantee.

Resorts with dense local populations and nearby competition would seem to have plenty of motive to inflate snowfall totals, but the results of this analysis were inconclusive. Depending on which measure of government snowfall was used (NOAA or SNODAS), the results differed.

What do you think? Does your local hill over-report, or are you lucky to live near a resort that under-reports? Those quiet 3-5″ days that end up knee-deep are hard to beat.

Reference:

Zinman, Jonathan, and Eric Zitzewitz Wintertime for Deceptive Advertising? (2016) American Economic Journal: Applied Economics, 8(1): 177-92.