Encore - Hair Ice

November 07, 2015


Take a look back at some of the EPODs our viewers found particularly eye-catching. Today, and every Saturday EPOD invites you to rediscover favorites from the past. Saturday posts feature an EPOD that was chosen by viewers like you in our monthly Viewers’ Choice polls. Join us as we look back at these intriguing and captivating images.

Photographer: Helga Schöps
Summary Authors: Helga Schöps; Jim Foster

February 2010 Earth Science Picture of the Day Viewer's ChoiceThe photo above showing a particularly beautiful example of hair ice was found in the Black Forest of southern Germany, near the town of Schwarzwald. Similar to needle ice, hair ice (in German it’s called Haareis) is a type of frost flower usually formed in dead or rotting wood and leaves during episodes of high humidity and low temperatures. According to Dr. Gerhard Wagner in Switzerland, hair ice is related to the presence of a fungus. For this type of frost to occur, water or fluid within the stems of certain plants is exuded to the surface by capillary action whereupon it immediately freezes. In some instances, the fluid, which isn’t sap, oozes to the air/bark surface via a fracture in the woody material. Under just the right circumstances, amazingly delicate needles of ice are created. Photo taken on February 16, 2007.