Mars On Earth: Learning about past climate conditions in the High Arctic

Note: The following story first appeared in the Mars Society’s “Martian Chronicles” newsletter.

The Canadian High Arctic is a distinct region of our
planet in the way that it supports life, responds to shifts in
the climate, and affects the environments of the rest of the
globe. Investigation of High Arctic climate and
environmental change is needed to better understand their
global effects and to monitor this
pristine and sensitive region. This
necessitates an understanding of
the region’s natural variability and
of how it has changed through time.
Given the remote and isolated
nature of this area, it is not
surprising that this past climate
data from the High Arctic is sparse.
However, through a recent increase
in scientific activities geared at
understanding High Arctic climate
change, this is slowly changing.

One method of retrieving
long-term past climate data in the High Arctic involves
tapping into the wealth of information trapped in the
sediment record at the bottom of the existing (e.g. Sapphire
Lake in Haughton Crater) and extinct lakes (e.g. Haughton
Crater which became a lake post-impact, but has since
drained out) found on Devon Island and other High Arctic
sites. Essentially the sediment reads like the pages of a
great climate book, since through time organic and inorganic
fallout from within and around the lake accumulates and
provides a historical climate record that would otherwise
be unattainable. By taking a sediment core of the lake we
can acquire this precious information. This type of research,
aimed at the study of lake history, is termed paleolimnology.

The biological remains of diatoms, for example,
found within these sediment cores, can be used as biological
mechanism to track and
understand past climate
change. Diatoms are
unicellular algae with glass
(siliceous) cell walls, and are
used as biological indicators of
past climate change, since their
populations will shift as their
environment shifts, thus
allowing us to infer changes in
a lake’s climate history. They
preserve exceptionally well in
the sediment record, and their
remains can be incredibly
ornate and beautiful (see Feb 1999 National Geographic
for more info).

The High Arctic is a beautiful and pristine region,
and through further paleolimnological studies we hope to
better understand its climate history as a tool for predicting
and managing future climate change in this sensitive area.
Darlene and Marianne
extracting a sediment core.