Investigating Snow
Average North American and Eurasian Snow Cover

In some parts of the globe, snow is an annual fact of life, while in other places there is hardly ever a flake!


How does our snow cover across the Northern Hemisphere compare from year to year? The Rutgers University Global Snow Lab now offers maps showing snow cover today and historically.

Scroll through the dates to view snow cover for each month of the year. Try looking at today's snow cover and then what it looked like 1, 2, or 5 years ago on the same date.

snow map
Explore these questions:
* What does this "tell" you about snow cover?
* In which month is the largest area covered with snow? In which month is the smallest area covered with snow?
* Which parts of North America get the most snow? The least? How would you explain that?
* Which parts of North America get snow the earliest? The latest? How would you explain that?
* When does the snow cover seem to reverse direction? What do you think causes that?
* What other factors are also changing along with the seasons? How might these affect the amount of snow cover?
  1. Look closely at this map. It shows how long snow cover lasted (from 0 to 360 days), on average, during the same period.

  2. Explore these questions:
    * What does this "tell" you about the duration of snow cover in different parts of North America?
    * Why do you think these differences exist?
    * What other factors are also changing along with the seasons? How might these affect how long snow cover lasts?
    * What new questions do you have?