Monday, December 07, 2009
What is a Pressure Ridge?
A pressure ridge is formed where an ice sheet
is broken and one piece rides over the other.
The actual "pressure" is often provided by winds,
storms or ocean currents that can be many miles
distant acting on the edge of the ice sheet.
This evening, I took a tour of the Pressure
Ridges near Scott Base, with the Recreation
Department. I've seen them for years, but
had never had the chance to go on one of the
trips. In a word, they were FANTASTIC!
They extend for almost two miles along the
edge of the landscape and are eerily other-
worldly. In a way, the landscape reminds me
of Arches National Park, in Utah, but a much
colder, whiter version.
Along the way, we saw a mother and baby seal
that were lounging in the sun. In a few weeks
there will be dozens of these seals here along
the ridges, but for now, we only saw three.
We followed a group leader along "trails" that
had been approved by Scott Base and McMurdo's
outdoor safety group. The trail was fairly
sturdy, but I was glad I had my boot ice grips
and trekking poles. It definitely made for a
more fun experience, knowing that footing would
be solid. There were lots of mushy places though
as well and I buried my foot once in about a foot
of slush. Ugh.
It was also interesting to see Scott Base from
such a different angle.
The tours are ending this week as the ice is
becoming too unpredictable and slushy so I'm
glad I had the chance to experience this