Here is something that we are likely to see less and less of with the accumulation of greenhouse gasses.
Living in a cold climate with somewhat restricted caving opportunities the ice formations are a special treat – though – keeping in mind, the bats hibernate through the winter in many caves and so dont cave in known bat caves during the colder months – waking bats at the wrong time could kill them.
The above spike towered up beneath the surface well after the surface snow had melted. My caving partner and I made a late spring exploration in one of our favorite caving areas to enjoy this unusual phenomenon.
In alpine and polar regions cave ice develops much as it would under regular circumstances however the formation of temperate region cave ice is a more complicated process.
In a multi entrance cave that has entrances at different elevations the air flow changes with the climate. In colder months the freezing air is drawn through the lower openings and vented out the top. In the summer the process is reversed. Obviously there needs to be a greater flow of cold air through the cave than warm, hence, “A colder climate than the temperature” (Emil Silvestre – Perennial Ice in Caves in Temperate Climate and its Significance) – though sadly as has been pointed out, there is no longer such a thing as temperate caves that are showing an increasing balance of ice accumulation – everything is melting.
Where I live – an area once referred to as “The Cave Desert” there are many examples of “the ice box phenomenon”. The Niagara Escarpment is riven by deep crevices and they act as pools where cold air can accumulate and preserve ice well into the summer months. The cold air trap is most usually found in single entrance caves that dip down at a steep angle – eg. a crevice cave. Cold air slides down as it is heavier and warm air is pushed out the top of the shaft. The entrence to these ice box traps needs to be large enough to allow a suitable exchange of air to overcome the “geothermal flux” – the rock is in need of constant cooling from above as it maintains its own ambient temperature from the crust beneath.