They’re already starting to appear — right in your neighborhood and perhaps right in your yard. I call them tree doughnuts. They’re the circles of thawing that appear around the bases of deciduous trees every year about this time.
The dark bark of the trees absorbs the increasing heat of the sun’s rays and radiates that heat, melting the snow around the base of the tree. At first, the snow merely widens away from the tree. That allows the sun to penetrate farther down, radiating more heat to the snow and widening the circle of meltdown.
Eventually, this microclimate of melting expands, revealing a few inches of forest floor around the tree. It looks as if each tree is wearing a doughnut. Sometimes, you’ll see a whole hillside of trees, each encircled by its little apron of earth. As the spring thaw continues, the circles widen and soon all the snow is gone.
It’s just one more subtle part of the transition from winter to spring in the North.