Frost-free Days - Why Give a Hoot?

Living in Aspen has more than enough perks, from the incredible skiing in the winter to endless backpacking in the summer. The amazing snow and the beautiful sunny days makes you grow accustomed to the weather patterns and the climate of the area.

As a Naturalist and avid outdoor lover I couldn’t help but wonder, how is the warming of our planet affecting the Aspen area? A few naturalists and I dug into some data, provided by NOAA and Colorado Basin River Forecast Center, for the Independence Pass Snotel Site and found a noticeable change in frost-free days in the recent past. There are a lot of climate change numbers, from temperature increases to carbon emissions, it’s hard to keep up with all of the numbers. Focusing on the Aspen region we looked at the number of frost-free days recorded at the Independence Pass Snotel Site. Now, you maybe asking yourself: what exactly are frost-free days? Well, frost-free days are the number of days in a year with minimum temperatures above freezing (0° Celsius). 

This data was collected by the Natural Resource Conservation Service of the USDA.

The above record shows a linear increase in the number of frost-free days at the Independence Snotel site from 1986 to 2010. Starting with only 27 frost-free days in 1986 it has been hiking up to 53 days in 1992, 84 in 2000 and onward to 106 frost-free days last winter in 2010. It is hard to look at this data and not think, how does this impact our seasonal snowpack? How will more forst-free days affect our forests? Our rivers? Weltands? Fishing? White water rafting? Agriculture? And, what will this graph look like in twenty years?