While Wisconsin more so conjures images of snow and cold (and cheese) than it does the ocean, it actually has a spectacular coastline along Lake Michigan that undergoes traditional coastal geomorphology processes.
Cave Point County Park in Door County, Wisconsin features great examples of wave-cut platforms (shown in the above photos).
Wave-cut platforms are the remnants of previous cliff lines. As the waves roll in, they continually pound against and erode the cliffs, causing undercutting–cutting deeper and deeper in the rock until a cave forms (shown below).
Due to the force of gravity and freeze-thaw cycles weakening the rock above the undercut areas, mass wasting erosion of the existing cliff face occurs, leaving behind a flat platform at sea level.
The cliff will continue to retreat as these erosional processes take place, progressively leaving behind these bedrock ledges.
the colours rippling through these night skies are from atmospheric airglow and the gravity waves passing through them. airglow is the result of chemiluminescence in the thermosphere, where ultraviolet radiation from the sun excites atoms, mostly oxygen and nitrogen, which emit photons (or varying wavelengths of light that correspond to a colour on the visible spectrum) as they collide to form new molecules like nitric oxide.
airglow can look rippled when gravity (or buoyancy, and not gravitational) waves pass through the atmosphere. whether from the updraft of a storm or air moving over mountainous terrain, a wave can form in a stable layer of the atmosphere, which grows as it rises from the lessening atmospheric pressure.
striped icebergs form as meltwater refreezes in crevasses atop glaciers before air bubbles can become trapped in the ice, which is later calved into icebergs, or when supercooled seawater freezes inside cracks beneath an ice shelf, which then becomes visible when the iceberg breaks off and flips.
over time, the weight of accumulated snow contorts and curves these blue bands of ice, as does erosion from waves and wind. dust and volcanic ash falling on the iceberg can darken the ice, while dissolved organic compounds entering from below can shade it towards cyan.
accumulated snow also compresses air bubbles trapped in the iceberg, thus preventing them from otherwise interfering with the passage of light. and because water absorbs photons from the red end of the visible spectrum much better than the blue end, bubble free ice takes on a blue colour.
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