Frosted Rose

January 17, 2018

Hoarfrost_on_rose_DSC_2329red

PhotographerLorenzo Rigutti
Summary AuthorsHelena Zapolsky; Lorenzo Rigutti 

BOTTOM222Ice segregation on plants and other surfaces sometimes yields an ephemeral combination of fragility and cold beauty. Flowers coated with hoar frost are sometimes referred to as ice flowers. Note that frost flowers are different and have nothing to do with actual flowers. Hoar frost or rime forms on surfaces when the atmosphere is much colder than the surface and when water vapor is plentiful. Large temperature gradients drive ice crystal growth. The morphology of ice crystals is very sensitive to temperature, humidity and pressure. Needle-shaped ice crystals, such as shown here on the rose and net, grow only in a very narrow interval of temperatures (appearing when the temperature is about 23 F or -5 C), and when supersaturation of water molecules in the atmosphere is high. These conditions were fulfilled during the nighttime hours of December 30, 2016, in Bois-Guillaume, France. During winter, look around and admire this wonderful creation of nature. Ice flowers such as these are short-lived-- enjoy them while you can.

Photo Details: TOP: Camera: NIKON D7100; Exposure Time: 0.033s (1/30); Aperture: ƒ/5.6; ISO equivalent: 800; Focal Length (35mm): 157; Software: GIMP 2.6.11. Insert - same except: Exposure Time: 0.017s (1/60); Aperture: ƒ/5.3; ISO equivalent: 900; Focal Length (35mm): 112.