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 DRAMATICALLY: FROM A FEW CENTIMETRES TO 5 METRES IN HEIGHT. INITIALLY,
THE SUN’S RAYS CAUSE RANDOM DIMPLES ON THE SURFACE OF THE SNOW. ONCE SUCH A
DIMPLE IS FORMED,
SUNLIGHT CAN BE REFLECTED WITHIN THE DIMPLE, INCREASING THE LOCALIZED SUBLIMATION.
AS THIS ACCELERATES,
DEEP TROUGHS ARE FORMED, LEAVING PEAKS OF ICE STANDING BETWEEN THEM.
Penitentes,
or nieves penitentes (Spanish for "penitent-shaped snows"), are a
snow formation found at high altitudes. They take the form of tall thin blades
of hardened snow or ice, closely spaced with the blades oriented towards the
general direction of the sun.
The
Maelstrom When you hear a name like maelstrom, you just know it’s about
something wicked. Introduced in English by Edgar Allan Poe from the Nordic
languages, from which it came from the Dutch word maelstrom (maalstroom in
modern spelling), it literally means crushing current, which is quite a very
good description.
These
odd structures really catch the attention, so much so I became curious and
researched the mechanism behind their formation and whatever else I could find
out about these strange formations. Interestingly they are first described in
the scientific literature by Charles Darwin who encountered penitentes near the
Piuquenes Pass in the Andes Mountains. Called 'snow
cups' or 'penitentes' due to their resemblance to pilgrims or
hooded religious figures the results can be startling in their strangeness. The
pillars can be taller than a person, but the tallest I have seen on Mauna Kea
this winter are about one meter, mostly just half a meter, I suspect they could
be taller if given a chance, but that is the depth of the remaining snow
fields.
The conditions for forming penitentes have been present at the summit
for the last couple months, and the process has been carving at the deeper
remaining snow fields on the tops of the ridges and north sides of the pu'us at
the summit. Currently entire snow fields of acres in size are carved deeply
with these penitentes in the summit area. This has resulted in entire gardens
of penitentes along the roads at the summit and another reason why the summit
continues to be such a beautiful and fascinating place.
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