Snowmelt Pattern on Patio

April 09, 2013

Snow Patterns on patio

Photographer: Richard Ogilvy
Summary Author: Richard Ogilvy; Jim Foster

At first glance, the photo above shows what looks to be a particularly sloppy job of applying mortar, but in fact, it's what's left of a recent snowfall. It was taken the morning of March 19, 2013, from my home in Forres, Scotland, after a late season, overnight snowfall collected on a stone patio. Despite the chilly air temperature, residual heat from the previous day's sunshine stored in the stone slabs is melting the snow, thereby dramatically outlining the stone pattern. The mineral soil and vegetation in the spaces between the slabs don’t provide this heat sink and thus the snow lingers there until the current day’s solar energy melts it directly. Note that where the stone was more shadowed (at right) some snow remains, having previously received less sunshine.

Photo details: Camera Maker: FUJIFILM; Camera Model: FinePix S5000; Focal Length: 7.5mm; Aperture: f/4.0; Exposure Time: 0.0029 s (1/350); ISO equiv: 160; Software: Digital Camera FinePix S5000 Ver3.00. Photo taken at 8:30 a.m.