Ice Leads in Antarctica
A network of cracks can be seen in ice in Antarctica (center right). These cracks, called leads, open when warmer conditions cause the ice to break apart, and refreeze when colder conditions are present.
The white swirls in the water are caused by ice forming in the presence of eddy-currents. These currents move in the opposite direction of normal water flow. As ice forms on the surface, it takes on the shape of the currents, making their movements visible to the naked eye.