Clear and cold

Yesterday dawned clear and cold. The rain had stopped; the stratus was gone. The day offered many delights, a few of which are below.

Birds improve their insulation by fluffing feathers. This heron has fluffed the feathers on its breast and belly.

Cold air over the (warmer) water causes vertical temperature gradients that result in both mirages and convection. The strange structure near the centre of the picture is a portion of the cable ferry at Harrop. Most of the hull has vanished; the bridge is seen right way up and inverted; the whole thing appears to be floating above the surface of the water. Turbulence from the convection has further garbled its image.

As the Sun sets in the west, an eastern ridge provides a backdrop for both shadow and reddened sunlight.

The backdrop for the transition from shadow to reddened sunlight is now the atmosphere, itself. The dark lower region is the Earth’s shadow. The pinkish upper region is called the anti-twilight arch. Although Sphinx Mountain is no longer in direct sunlight, it nevertheless also appears coloured. This is the alpenglow: the snow is illuminated by the pinkish skylight.