If you’re native to Colorado like I am, it’s pretty obvious that our winters are not what they used to be and our summers feel like they’re drying up.
Although I’ve grown up here, I am no expert on weather, climate change or even snow for that matter. I am, however, interested in learning more about this beautiful frozen powder and how the lack thereof affects us in more ways than one.
Explaining Snowpack
In mountainous areas that experience a winter, precipitation falls from the sky as temperatures drop below-freezing and layers of snow accumulate on the ground. For months these subsequent layers of snow compress, each one form a different snowfall, to create a snowpack.
The Significance of Snowpack
Studies in recent years show that seasonal snow trends of fall and spring months are resulting in less than average annual snowfall totals. Warmer winters are also preventing solid snowpack from forming in the Rocky Mountains. As a result of this, the Western United States has become a global snow-drought “hotspot” that suffers from raging wildfire seasons and a shortage of essential water supply.
As mountain snowpack melts, water is slowly released into streams, rivers and lakes. In total, it supplies up to 50% of the world’s freshwater and around 75% of water to the American West. Snowmelt directly impacts the Colorado River, which provides water and power to seven different states and is an essential resource for the warmer months to come.
How is it Measured?
Snowpack is measured in snow/water equivalent and the amount of water released by snowmelt varies depending on the density of the snow. For example, 3.8 centimeters of water per 30 centimeters of snow can be retained, unless high winds or warm temperatures prevent the snowpack from accumulating.
Currently, there are many ways scientists study the depth and weight of snowpack. One commonly used instrument, called a Snow Depth Sensor, works by transmitting ultrasonic pulses to and from a target surface while a temperature probe provides an air temperature measurement. These two readings give scientists an accurate reading of the depth of snowpack at a given location.
To track snowpack levels against historic averages, the United States Department of Agriculture and the National Resources Conservation Service (NRCS) releases updates on the current snow water equivalent to percent of normal. Organized by river basin, such as the South Platte, Colorado River, Arkansas River or Gunnison River basins in Colorado, these updates are a helpful resource to help us understand how each part of our state is faring and help us forecast river flows for summer months and beyond before the snowpack even begins to melt.
For Colorado residents, these resources can be found online at: https://www.nrcs.usda.gov/wps/portal/nrcs/main/co/snow/
It’s Our Lifeline
You don’t have to be an expert to understand how snowpack is a vital resource for both the environment and society. Disturbances in the snowpack cycle directly affect our agriculture, recreation and increases insect and fire risk to our forests.
As most Coloradans would say when we finally get snow, “Lord knows we need it!”