96 DISCOVERMAGAZINE.COM
for which drawings or written notes previously would
have been used.
But it took until the late 1950s for the true potential
of repeat photography to emerge, when two scientists
at the University of Arizona set out to study the ecol-
ogy of the Sonoran Desert. Because they wanted to
understand large-scale change over the long term,
including how decades of agriculture had affected
biodiversity, simply taking multiple pictures over
time at a single site wasn’t enough: They needed
photos going back to before they were born.
So instead of beginning their research outdoors,
bioclimatologist James Hastings and botanist
Raymond Turner started working in library archives,
retrieving Sonoran Desert photographs from as early
as the 1880s. Some pictures were taken for scientific
purposes, others for surveying or for documentation
of the landscape. After rephotographing 300 sites over
1 vertical mile of land, they published The Desert Mile,
a book that not only transformed knowledge of the
desert but also alerted other scientists to the value of
historical imagery.
“Once you start looking at old photographs, you look
at things a whole different way,”
says Robert Webb, a retired U.S.
Geological Survey hydrologist
and repeat photographer who
worked closely with Turner on
a second edition of the book,
published in 2003. “You start
to realize there’s a whole other
dimension, which is time, and it
makes you recognize that there’s
a dynamism to these systems.”
Because such change is
universal in the natural world,
and because photography is
now 180 years old, recapitula-
tion of historical photographs
has gained traction in many
fields. Webb has used old
photos to study the behavior
of waterways such as the Colorado River and to see
how vegetation has changed in the Grand Canyon.
Others have investigated the breakup of polar ice
sheets and the retreat of Alaskan glaciers in the wake
of climate change.
“Repeat photography is very different from many
scientific techniques because it can not only be used
to answer a number of research questions, but can
also generate a lot of research questions,” says Webb.
With a location, an archive and a camera, researchers
expose themselves to whole new realms of inquiry.
NEW TOOLS, NEW GROWTH
After two summers of scrambling around Jasper
National Park, Higgs thought he was finished with
cameras and mountaineering in 1999. As an ecolo-
gist, he appreciated repeat photography — even
more so as he learned about Webb, Turner and his
other predecessors — but he was eager to return to
his everyday work on ecosystem restoration. It was
an accident of history that pulled him back into
the archives and led him to found the Mountain
Legacy Project.
Unlike most of Europe and the U.S., Canada was
still largely terra incognita in the late 19th cen-
tury. Eager to build railways opening up the land
to mining and settlement, the government sought
to map thousands of miles of rugged terrain at an
unprecedented rate. Laying down chains to measure
distance on the ground — the standard surveying
technique of the period — was far too laborious, and
it was practically useless for plotting elevation in a
mountainous region. As the government grew impa-
tient, a surveyor named Edouard Deville proposed
trying out a method invented in his native France:
With the help of an optical device called a theodolite,
which measures angles, a surveyor could translate a
comprehensive set of panoramic photographs into an
accurate topographic map.
Deville and his successors succeeded, charting
most of Canada between the 1880s and the first
decades of the 20th century. Once their maps were
complete, the photos were no longer needed. The
heavy glass-plate negatives were set to be destroyed,
but they ended up misfiled in an Ottawa warehouse
(perhaps intentionally diverted by a far-sighted civil
“You start
to realize
there’s
a whole
other
dimension,
which is
time, and it
makes you
recognize
that
there’s a
dynamism
to these
systems.”
— Robert Webb,
hydrologist and
repeat photographerTHE
MO
UNTAINLE
GA
C
Y
PR
O
JECTHISTORY LESSONS
The Canadian
Rockies’ Opabin Peak
and surroundings,
in 1908 and 2012.