66 SMITHSONIAN | April 2020
Researchers transport equipment on
a sled pulled by a snowmobile. The
main research sites lie within half
a mile of the Polarstern, but
others are as far as
30 miles away.BYLINESEsther Horvath, a Germany-based
photojournalist, is spending six months
aboard the Polarstern documenting
the MOSAiC expedition. This is her
fi rst assignment for Smithsonian.in Arctic ice and seawater she collected,
measuring the minuscule amounts of meth-
ane and other gases the microbes digest or
produce during their life cycles. She also col-
lected air samples to study how algae, bacte-
ria and other particles blown into the air act
as nuclei for ice crystals in the atmosphere,
“seeding” the formation of Arctic clouds—
clouds that in turn aff ect the amounts of
snow and sunlight that reach the sea ice.
The work poses countless challenges.
Fissures can form in the ice and block the
way to established research sites, forcing
the researches to fi nd alternative routes.
The temperatures plummeted to 20 degrees
below zero. In mid-November, a violent
storm opened up a new crack between the
Polarstern and its fl oe, knocking over a 100-
foot meteorological tower and threatening
to snap power cables. But spirits remained
high, according to Creamean , sustained by
the international camaraderie and even the
occasional soccer game on the ice.
During long hours in the ice-coring tent,
Creamean would occasionally step outside
and gaze at the moon or the stars and try
to take in the vastness of the Arctic night.
“Sometimes the blowing snow would spar-
kle, and you’d just be struck by the beauty
of it all,” she says. “To know that you were
one of the very few people who had ever
seen that, who had ever stepped foot up
there—it was awe-inspiring.”
In early January, Creamean fl ew home
to Colorado hauling an Igloo cooler packed
with samples of Arctic seawater, ice and air.
Over the coming months, she’ll identify the
bacteria, phytoplankton and other micro-
organisms in her samples from their DNA.
Then, she’ll mimic the process of cloud for-
mation in her lab , watching to see which
kinds of microbes most readily seed clouds
at subzero temperatures. Later, she’ll repeat
the process with samples brought back from
the Polarstern during spring, summer and
fall to observe how the makeup of the atmo-
sphere changes as temperatures warm, the
ice melts, and microbes in the surface water
are blown into the air. Eventually, she hopes
to pin down the precise role microbes in
the melting ice play in the formation of the
clouds. “It’s a small piece of the puzzle, but
it’s a crucial one,” she says. “If we can better
understand how clouds form, we can better
understand how Arctic weather and climate
is aff ected by diff erent processes—and how
those changes will aff ect all of us.”
Michelle Nijhuis is an award-winning science
reporter based in White Salmon, Washington.