The rounds of snow and ice experienced over the past couple of weeks have left many communities in the Tri State in a slushy mess. Although the plows have cleared through most streets, many front yards and retail parking lots continue to have lumps of snow scattered throughout. Even as temperatures rise beyond the freezing-mark, eye sores of dirty snow and ice are still seen, why is that?
The progression of melting snow works in two phases. One phase is actually warming the snow and ice to 32 degrees. Multiple external variables could limit this; such as the diurnal sun angle, cloud coverage and ground temperatures (grassy areas vs black pavement). The second phase is a called Latent Heat of Fusion. This refers to energy transferred between a body and its surroundings, defined by the occurrence or non-occurrence of temperature change; they depend on the properties of the body. Simply put, the larger the mass of snow is, the longer it will take to melt. One real-world example is observing how quickly a single cube of ice melts compared to a bag of ice under the same condition. The larger mounds of snow left behind from plowing will take much longer to melt and evaporate compared to lesser amounts.
If you are completely fed up with seeing snow altogether, our sunny weather this week will work in your favor. One thing to highlight is albedo. Albedo is the measurement of how reflective an object is on a scale of 1 to 100. Fresh snowfall has one of the highest albedo ratings of 99. However, due to the salt, sand and general road traffic the fresh snow has turned into lumps of dirty snow which lowers its albedo level. A lower albedo level increases the chance for the leftover snow to absorb and trap radiation from the sun which will allow for faster melting.
The forecast in the coming days also calls for breezy and warmer conditions which will enable even more rapid evaporation and melting.