Snow Cover and Temperature

This video shows a snowy day where snow has melted on sidewalks and streets but remained on grassy areas. Snow reflects sunlight more than darker surfaces such as soil. Iowa’s winters self-perpetuate as the snow reflects the sun, keeping the temperature cooler. This, in turn, can influence climate over time. Understanding the role of snow in moderating climate is critical to understanding issues related to climate change and weather patterns. A decline in snow cover worldwide due to increased temperatures has consequences for future climate events.

• Why is there so much glare on sunny days when it snows?

• Why is it hard to look at snow when sunlight shines on it while it is not difficult to look at plain cement or grass?
• Why do skiers, snowboarders, and snowmobilers wear tinted glasses/goggles?
• How might the glare from the snow affect the temperature at the snow’s surface? 
• If they watch the video: Why would snow cause damage to the eyes?

Students could:

• Download a light meter app and use this to see what surfaces reflect light and what surfaces do not. Have them go outside and measure reflection from the snow, cement, lawn, buildings, etc.
• Make conclusions about how color, texture, etc. affect light reflection.
• Define the word, “albedo” and explain how it relates to the reflectivity of the sun from earth surfaces. How might albedo affect the overall temperature? Labs are available online at the University of New Hampshire Student Climate Data page.
• Investigate how might albedo affect the climate, what might be the effect of lots of snow or loss of snow (melting glaciers), what might be the effect of having low albedo on the earth, and what surfaces might keep the earth warm?
• Set up containers of different substances such as sand, dark soil, water, etc. and measure the temperature change over time if these are set in the sun (or under a bulb). 

• NASA Earth Observatory | Measuring Earth’s Albedo: NASA data and maps on Earth’s albedo.
• NOAA | Amazing Albedo: NOAA lab in which students use thermometers, white and dark paper, and lamps to measure differences in albedo between the light and dark materials. Connections are made to albedo in Antarctica.