Columbia, SC — Cold weather has definite drawbacks. People are generally confined indoors, as it is not comfortable to walk or exercise outdoors, and prolonged cold weather exacerbates the cabin fever that already afflicts us in winter.
Cold weather also costs money, as our heating systems have to do more work than in more temperate weather to bring our indoor temperature up to the same level. Increased usage puts a big burden on power plants, increasing their chance of breaking down and bringing cold and darkness to many.
However, there is one aspect of the low temperatures that is positive for society: They conserve water.
In colder weather, the evaporation of water from the land surface — lakes, ponds, rivers and other water bodies — is very close to zero. When coupled with winter rainfall or snowfall, this results in a positive water balance for the land surface.
And we all need this, in order for vegetation to grow and aquatic life to flourish.
Here’s why: Summertime evaporation from an open body of water can range from 4 cm and 7.5 cm per day. Over 30 days, this would be a loss of 1.2 meters to 2.2 meters of water in our lakes and rivers. Over the course of a S.C. summer, this would be at least 3.5 meters, or 11.5 feet. This is why, during periods of drought, we’ve seen water levels in neighborhood ponds drop low enough to see the bottom.
The cold weather we’re struggling through is conserving a lot of water, and we can expect to see higher lake and river levels in the spring. In addition, this surplus surface storage will result in a slow but steady recharge of ground-water aquifers. Coming after the hot summers of 2012 and 2013, this will provide some water relief to the Midlands.
Of course these cold temperatures make us long for warmer weather. In two months or so, spring will be here, and gone will be the days of brown lawns, bare trees and the silent cold. The grass will green, the trees will have leaves, the air will be filled with the sounds of birds singing, and the cold weather will be a distant memory. Until next winter … .
Department of Earth and Ocean Sciences, USC