Page 18 - AlertDiver_Winter2013

After thousands of dives — many remote, under ice or
in the company of dangerous animals, I thought I had
conquered all my diving fears. That’s when I got an
assignment for National Geographic that put me back
into dive school. To the viewer, it may seem like the images we make
for National Geographic are “found objects”: opportunities that
appear in front of our cameras that we just happen to snap because
we are at the right place at the right time. Sure, sometimes it happens
that way, but for the most part every image I have made starts at
the drawing board. I spend weeks or even months doing research,
preparation and planning before I ever get to push the shutter.
My own creative process demands that I work backward. I first
imagine the shot I want. I sketch it on a piece of paper; I talk to other
photographers, scientists and explorers; I roam the Internet looking for
specific locations, boats, experts, equipment, tides, the position of the
sun, the weather — every possible variable that might affect my shot.
With some images it takes months or even years for all the pieces to
come into place. It is not that I am posing or staging things; I work hard
to make sure I am at a place and time in which things are happening.
And this is how I find myself in the jungles of Mexico’s Yucatan
Peninsula with a knot in my stomach.
The shot I want to make demands that I dive almost 100 feet
deeper than I ever have before (to approximately 300 feet) and that
I work inside a flooded cave in the pitch black. I will have to rappel
my camera, my rebreather and myself down a 70-foot line just to
reach the start of the dive.
I have come to Playa del Carmen, Mexico, to learn how to cave
dive at great depths using a rebreather. This morning my instructor,
Matt, is teaching me how to navigate blindly inside the guts of a
flooded cave. It doesn’t take long for my mind to start playing tricks
which ran aground in 1827 while being chased by
the British warship Nimble, which was patrolling
Florida waters to enforce the ban on the slave
trade. NABS divers surveyed the second of three
possible locations for the Guerrero in 2010 and
2012, and they plan to return to South Florida to
investigate — and potentially rule out — a third
location near Carysfort Reef in the Upper Keys.
Unlike the Bell, which is an easily identifiable
wreck, Altmeier said the likely Guerrero site is
disarticulated, which means the artifacts are
scattered over a large area. “There’s nothing
definitive, and there may never be,” she said. But
during survey dives on the site, the NABS team
identified period-appropriate artifacts.
Haigler outlined the steps the team takes
underwater: Survey the entire site to establish its
boundaries. Decide how to orient the baselines,
which run the length of the wreck. Set clips at
equal distances along the baseline. Put pin flags
next to artifacts or points of interest.
Next is trilateration, which employs “three
points to locate a point of interest relative to the
baseline, which we set in what we perceive to
be the middle of the wreck,” Haigler said. Then
the team members sketch each point of interest.
“That’s when it really gets challenging,” said
Haigler. “You’re hovering, you’re looking, you’re
measuring, and you’re drawing underwater” — all
while maintaining perfect neutral buoyancy so as
not to damage the site or kick up silt.
“Most of what we’re doing is data collection
that will aid the archaeologists in fully determining
what is there,” Washington said. Using computer-
aided design and the expertise of Gayle Patrick,
a NABS member and architect, over the course
of weeks the collected data is turned into a site
map like the one the group completed of the likely
Guerrero site.
The NABS divers’ work on the Guerrero was
featured in a recent episode of Miami public
television station WPBT’s “Changing Seas” series,
which will be available online atwww.changingseas.
tv. The “Sunken Stories” episode follows the divers
as they learned to survey and when they returned to
the water to look for the Guerrero.
— Karen Quist
DIVE SLATE //
16 | winter 2013
Occupational
Hazards
In pursuit of the images he
needed, National Geographic
photographer Paul Nicklen
undertook cave, rebreather
and deep-trimix training to
get the job done.
The Hannah M. Bell
Harold Appleyard
Cristina Mittermeier