Let it Snow: Why it Matters
This white, fluffy, and cold abundance falling from the sky brings a mixture of feelings and expectations for people worldwide. It can bring joy to those excited for school “snow days”, winter holidays, winter sports, and the scenic views of the silent, powdery, blank canvas of accumulated snowflakes throughout the environment. It can also bring irritation, frustration, and disgust from people not wanting the frigid weather, icy road conditions, car troubles, layers of clothing, and exhaustion following snow shoveling. But is all of this necessary? Can’t we just enjoy the beautiful, sunny, warming temperatures like that of spring, summer, and autumn year-round? Do we have to endure the annual snowfall? Yes, and here’s why.
What is snow?
Snow Albedo
The whiter the surface, the greater percentage of solar radiation (a) is reflected away from the Earth, with snow having the highest at 90%. Source: Our Winter World
With enough humidity and low temperatures to cross the freezing threshold of 0°C (32°F), water vapor bypasses its liquid stage and condenses directly into ice that forms in clouds. This ice gathers and freezes the surrounding water vapor in the air to form growing snow pellets that eventually fall to the ground.
Snow Albedo
In a time where global temperatures are getting warmer, glaciers are melting, and we’ve just experienced the decade’s hottest summers… snowfall is just what we need. Solar radiation (light energy and heat emitted from the sun) absorbed by the Earth’s surface causes warming if nothing protects it from the sun’s rays. Snow acts as the “sunscreen” that the Earth needs due to its albedo. Albedo is a Latin word meaning white, and snow’s white appearance helps the Earth to reflect 90% of the sun’s radiation into space instead of absorbing it, allowing the Earth to cool. Without it, Earth’s land can only reflect 10-20%, ice reflects 50%, and the open ocean reflects only 6%.
Water Supply
Along with reflecting solar radiation, snow is also one of our most important water sources. Snowmelt helps to supply our aquifers (underground freshwater storage) and dams with water that we use to drink, produce food, ship supplies, power electricity (hydroelectricity), and more.
While not all areas of the country receive snow, snowmelt from Northern, Midwestern, and Eastern states is crucial to those who rely on the downstream flow of this water source. Without abundant snowpacks, Western and Southwestern states are experiencing increasing bouts of droughts and wildfires due to the lack of water, dry air, dry soil, and growing heat temperatures. Although rainfall is helpful, snowmelt is absorbed by soil at a much slower rate, helping to nourish the soil over time in preparation for the following seasons of plant growth, while rainfall experiences immediate absorption but quicker evaporation leading to dryer soils and erosion. Rain can also cause too much absorption leading to more landslides and flooding in our Southern states.
Animal Survival
Many ecosystems and animals depend on snow and winter temperatures to prepare for important life cycles, seasonal changes, and migration and are physiologically dependent on the appearance and protection of snow. Like that of the snowshoe hare whose fur is adapted to turn white in the winter to camouflage from predators, but with winters becoming shorter, and snow melting sooner, these species are left exposed amongst their darker landscape. The reproductive cycles for birds are being disrupted due to the quickly changing weather conditions that are synchronized to their migration patterns, causing delayed/early breeding and low survival turnouts. Bats, a key environmental engineer, also face dehydration, food scarcity (from competition), and energy burnout if our winters keep decreasing while temperatures continue to rise. Many species of bats are temperature-sensitive like the Indiana Bat and Brown Bat, and with Tennessee being the home to 15 native bat species, the warming winters come at a high ecological risk when bats help with insect control, seed dispersal, pollination, and the establishment of cave communities through the nutrients provided in their guano (fertilizer).
So what’s in Knoxville’s Forecast?
El Niño & La Niña Explained. Source: Ocean Today (NOAA)
Last winter’s El Niño (a natural warming of the Pacific Ocean that causes more precipitation in the southern and eastern states, but increasing droughts in the west) helped produce one of Knoxville’s biggest snowstorms on record with an average of 8 inches of snowfall in January. With Knoxville usually experiencing an average of 4.6 inches of snowfall over the entire winter season, will this be the new normal? This is unclear as this winter season will see a weaker La Niña season (colder waters being pushed northward) that causes more drought conditions and warmer winters for the south, and wetter and colder conditions in the north. Studies are suggesting that warmer and snowless winters may be standard by 2040, leading to even harsher droughts in Tennessee and the country.
Snowless Winters in the Future? How to help
Conserve Energy: Unplug any unused appliances, turn off the lights in unattended rooms, wash clothes in cold water, use LED light bulbs, switch to energy-efficient appliances, utilize a smart thermostat, and practice mindful cooking.
Stay Informed: Keep up to date about climate issues regarding snowfall changes in your community, potential climate plans from your local and national policymakers, and look for opportunities to engage in creating a more sustainable future.
Travel sustainably: Try to avoid flying as the carbon emissions aid in snow and glacier melt, or opt for flights that offset their emissions if possible. Besides walking and biking, public transportation also aids in keeping our carbon emissions down drastically.
Adapt for the Climate: For those in agriculture, research, and plan to invest in a possible switch to crops that can grow in drier weather conditions.
Buy Sustainably: Support your local organizations and sustainable businesses that are helping to further the mission of zero waste and lowering their carbon emissions.