Sun Showers and Sunshine Floods

I often, beside the sea, used to gaze out at curtains of rain under clouds, like a skate under a foot.

I’m not sure whether these count as sun showers.  They are instances of rain seen at a distance, rain that can be enjoyed in sun, rain that is not falling on me.

The New York Times of June 21 has an article (sent to me by Howard Wilk) about “Sun Showers”: rain falling apparently without a cloud to fall from, though probably from a cloud that has moved away or has dissipated.

Minnaert’s delightful book on The Nature of Light and Color in the Open Air may well have a chapter on this.  Combinations of rain and sunlight can produce beautiful scenes – indeed, the rainbow, from sunlight behind you on rain in front of you, is a special case.

And the Scientific American of June had a piece (page 21, based on a report by the National Oceanic and Atmosphereic Administration) about “sunshine floods.”  These are high seas that inundate the land in the absence of apparent immediate cause such as storms.  America’s northeast and Gulf coasts have been seeing rising numbers of them.  At Norfolk, Virginia, they occurred two days a year in the 1980s; now, nine days a year.  They are an effect of global sea rise, and especially of the massive loss of Antarctic ice and the thermal expansion of ocean water.  NOAA has made a study of local flood risks along the coast, to an unprecedented level of detail, so as to help local authorities prepare for emergencies.

While politicians such as Senator James Imhofe deny that there is such a thing as global warming, city officials are already having to build earthen dikes and lay water-permeable pavements in hope of defending Norfolk against the floods.