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Tree Rime

This is a picture a took when I went to school in an early morning in late fall. The intricate shapes of the beautiful conical ice crystals on a tree branch are caused by several factors. When the air temperature is below freezing and there is enough moisture in the air, water vapor will condense directly into ice crystals. If the ambient temperature is low and the humidity is high, the ice crystals that form are usually more complex and intricate like the one in picture. During the formation process, ice crystals tend to form first on the raised or pointed parts of the surface of the object because these parts are more likely to lose heat, allowing water vapor to condense faster. This effect is particularly evident on natural structures such as branches, because the tips and edges of the branches provide an ideal environment. During the growth process, ice crystals will naturally arrange themselves according to the symmetry and electrical properties of the molecular structure.