Ice takes on all sorts of interesting asymmetrical and geometric shapes, from the icy platelets above to the incredible parallel ice shelves of the Arctic. Ellesmere Island is famous for its ice shelves, but unfortunately they are diminishing rapidly in the face of global warming. Climate change caused alarming losses in summer of 2008, and scientists are concerned that this special ecosystem may soon be lost forever.
These amazing ice spikes, generally known as penitentes due to their resemblance to processions of white-hooded monks, can be found on mountain glaciers and vary in size. As this accelerates, deep troughs are formed, leaving peaks of ice standing between them. Chile is home to the rugged mountain terrain of the Andes and the severe weather extremes at different altitudes make for some stunning ice formations, like daggers looking ice field.
A rare phenomenon usually only seen in extremely cold countries, scientists generally accept that Ice Circles are formed when surface ice gathers in the center of a body of water rather than the edges. A slow moving river current can create a slow turning eddy, which rotates, forming an ice disc. Very slowly the edges are ground down until a gap is formed between the eddy and the surrounding ice. These ice circles have been seen with diameters of over 500 feet and can also at times be found in clusters and groups atdifferent sizes. (Photo by Brook Tyler)
Ice cave are a type of natural cave that contains significant amounts of ice. At least a portion of the cave must have a temperature below 0 °C (32 °F) all year round, and water must have traveled into the cave's cold zone. There are many ice caves throughout the world, but the Eisriesenwelt Ice Caves in Austria are some of the largest known to man.
The growth of a frozen waterfall can proceed only gradually, for progressive freezing of the flowing water. There are thousands of frozen falls around the world. The one located at Beijing's Myun County attracts tourists from all over the country as well as internationally. A beautiful display of nature's art at work.
"I call them Karra Spirals, after my wife Karra Strickland who discovered them in our yard," says French. "They were all over town, spiraling down the braided metal guy-wires on telephone poles. Here's the curious thing: The wires were spun clockwise, while the snow formations were spun anti-clockwise. The hardened snow spirals were rotated opposite of the metal wire's weave. We also noticed that spirals near the top of the wires were longer (~1 meter) than spirals at the bottom (0.1 - 0.3 meters)--perhaps because of gravity?"
Indeed, the changing wavelength of the spiral suggests gravity played a role in their formation. This could be how heavy snow sags under its own weight when it clings to a braided wire. Why the spirals should oppose the braid, however, is not obvious. Readers with explanations are invited to submit them for consideration.
Despite it looks, this is not really a tidal wave but ice created from glacial movements forming tidal wave looks. Pretty cool.
Snow crystals form when tiny supercooled cloud droplets freeze. These droplets are able to remain liquid at temperatures lower than -18 °C (0r °F), because to freeze, a few molecules in the droplet need to get together by chance to form an arrangement similar to that in an ice lattice; then the droplet freezes around this "nucleus."
Icebergs in the Antarctic area sometimes have stripes, formed by layers of snow that react to different conditions. Blue stripes are often created when a crevice in the ice sheet fills up with meltwater and freezes so quickly that no bubbles form. When an iceberg falls into the sea, a layer of salty seawater can freeze to the underside. If this is rich in algae, it can form a green stripe. Brown, black and yellow lines are caused by sediment, picked up when the ice sheet grinds downhill towards the sea.
Ice flowers are formed on new layers of sea ice, from saturated water vapors that come up from under the ice through cracks. In contact with the cold air, the vapors start to freeze and the salt on the surface of the ice begins to crystallize and serves as a nucleus for the frozen vaporized water. Thus, molecule by molecule the ice flowers begin to take shape. They have recently been recognized as the dominant source of sea salt aerosol in Antarctica and scientist suspect they may be the main cause of tropospheric ozone depletion during the polar sunrise. One of the most beautiful frozen wonders on Earth, ice flowers are still a mystery to many people.
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