Subglacial Lakes
Adrienne is exploring East Antarctica!!!!
She heard there was a lake in the area
and she has been looking for it
everywhere!
I hope you can help her find it!
She is fascinated by lakes!
Maybe it is because she
comes from Ohio where
there are well over 1000
lakes!
1 2 6
7
5
3
4 9 8
OR maybe its because
she likes to snorkel?
OR maybe it is because she likes to
swim?
Yes that’s Adrienne swimming in a hole cut into the Ross Ice
Shelf in Antarctica. An ice shelf is a thick plate of floating
ice that forms where a glacier flows off the land.
credit: YoYo' Johnson for the Ice Stories Project, (c) Exploratorium, www.exploratorium.edu
Did you get an answer close to 152 cms?
Let’s have fun
with ice shelf
math!
That would be right IF
we were measuring
JUST what we can
see in the picture
….but with ice shelves
there is more…
From what you can see, how thick, from top to bottom,
do you think the ice is behind Adrienne? Ladder rungs
are generally one foot apart.* Can you use the ladder to
estimate ice thickness (height) in that area? Report
your answer in cms. *(1 inch is 2.54 cm)
~ 90% of the Ice Shelf extends
underwater!
10%
Water line
90%
Robin and Detlef are standing INSIDE the top 10% of the ice shelf !
Now estimate the TOTAL ice sheet
150 to 500
thickness in meters including both
metersthe
total
amounts above and below the water.
The Ross Ice Shelf
is THICK!
Scientists estimate
it ranges from 15 to
50 meters above
the water surface.
Can you
calculate in
135 to 450 meters
meters
the depth
below the ice!
of the ice sheet
that lies below
the water
surface?
But ice shelves are not subglacial lakes.
So what is a subglacial lake?
And where should we be looking?
‘Sub’ + ‘Glacial’ = Subglacial
A+B=C
Simple formula right?
Sub means ‘under’
Glacial refers to a glacier
Like this submarine is
‘under’ water
or ice sheet SO we are
looking for a lake underneath
a glacier…hmmm
But how far underneath?
Although Adrienne did
manage to swim in the
Ross Sea through a cut out
in the Ice Shelf, this was
under 15-50 meters (49164 ft.) of ice.
The lakes we are looking
for are under 3 to 4
kilometers (9843-13,123
ft.) of ice in the middle of
a glacier! She won’t be
swimming there!
15-50 m
3 to 4 km
How does water stay liquid under
all that ice?
Frozen lakes and ponds often
have water beneath a cover of
ice. Maybe you have even
skated on one?
But the Antarctic
subglacial lakes
Adrienne is looking for
are are NOT like any of
the lakes you might
have seen! These lakes
will be hard to find since
they are covered by a
HUGE ice sheet that
spreads over most of the
Antarctic continent. This
ice sheet is millions of
years old, and remember
it is up to 4 kms thick!
Let's try some activities and see if we can
find Adrienne’s missing lakes somewhere
under all that ice!
clicking on a photo below to start