Ponds
The seeds on ponds are mostly twigs or leaves, from which crystalline ice first grew within a supercooled water surface. Bacteria, fungi and dust in air or on the water surface can also initiate ice growth. These images are from late fall and early winter 2022 and 2023, when ice crystals formed, metamorphosed or melted several times, over, under and among colorful fall leaves.
Bladed Star With Dendrites: The blue color results from absorption of green and red wavelengths during internal reflections. The yellow is sunlight backscatter. These blades and mosaics are basic dendritic forms of fresh pond or lake ice. The long horizontal blade at left was about 110 cm long. Blades can be 2 meters long and comprise diagonal sections. The dendritic mosaics between the blades grew from the blades' sides as the blades lengthened. Note the seed twig in the star middle.
Blades Over Leaves: These blades range from 2 to 15 cm long. The greens (lilies), browns and oranges (oaks) are leaves just below the ice. Some blades grow from or join other blades.
Feathery Blades Growing From A Twig Seed: This telephoto makes these flat, horizontal crystal growths appear 3D, growing up from the base of the twig.
Dendrites and Blades Under An Overcast Sky: I took this on the afternoon of November 15, 2022. No sun, no color.
Sea Of Blades With Meltwater: The blades ranged from a few to 15 cm in length. The areas clear of crystallization are meltwater, with capillary fringes along edges and curving into corners.
Late Fall Polygons: These polygons occurred ten days after this pond first froze. The ice was up to 5 cm thick and isothermal at 32 degrees F. The polygons are recrystallized ice. Their formation was likely related to thermal convection caused by warm water. Within each polygon was a rough, star-like, clear-ice (aka black ice) formation commonly seen in spring when ice also becomes isothermal at 32 degrees F.
Melting Ice Blades With Seed Twig Over Fall Leaves. This image was taken almost directly overhead, and the seeding stump is in the middle. There are little melt pools on the blades, as evidenced by their elliptical outlines which are capillary fringes.
Near-shore Bladed Stars: This image shows melting in the lower third where thin black rings are troughs of a wavy pattern of capillary surface tension. The horizontal blade at left is about 14 cm long. Smooth blue areas are likely sky reflections. This photo was awarded an honorable mention in a local photography contest.
Shimmering Fall Through Broken Ice: Freezing also occurs during the spring. This image was taken on April 10, 2016, when the ice that had formed the past night began to break up.
Seed Twig And Triangle Of Blades: This image shows the curvature of capillary fringes in the meltwater between the triangle of blades. This photo appeared for February in the 2024 Geological Society of America calendar.
Leaf Edge Among Ice Blades
Ice Blade Cluster
White Moss-Blue Ice With Melt-Brown Leaf
Small Ice Blades Among Fall Debris
Advanced Metamorphosed Ice Blades With Edge Melt
Melt Margins, Decaying Ice and Fall Debris
Reeds Within Metamorphosed Ice
Metamorphosed Ice with Orange Leaf
Metamorphosed Ice-Star Blades With Seed Twig
Maze Of Metamorphosed Dendritic Ice
Metamorphosed Dendritic Ice Over Red Leaf
Metamorphosed Ice-Star Blades Without Seed Twig
Branch Upon Metamorphosed Ice
Moss And Leaf Upon Near Shore Ice
Golden Debris On Metamorphosed Ice
Blue Blades And Twig on Late Fall Leaves
Silvery Leaf And Metamorphosed Ice Blades
Transparent Ice Star
Silver Blades On Red With Seed Twig
Melting Ice Blades Among Fall Leaves
Silver Star On Red
Melting Ice Stars And Blades In Late Fall
Teal Star With Moss
Radial Blades Over Orange Leaves
Triangle of Blue Blades And Elliptical Capillary Fringes
Red-Blue-Green Star With Dendrites
Blue Capillary Ellipses On Ice Among Fall Leaves
Blue Capillary Swirls On Ice With Green-Veined Leaf
Fall Leaves Beneath Blue Capillary Ellipses On Ice
Blue Blades On Twig Head
Blue Blades On Twig Head Detail
Pipkrakes extruded from clay: These extrusions are obviously not "pond" ice but overlooked the north end of my photogenic pond. They are sometimes referred to as needle ice. They were about 10 cm long.
Blue pond ice blades and shards of blades, fall leaves and a log impregnated with blue ice. Image taken January 2, 2024, after yet another early winter warm spell.