Then and now: Coral comparisons offer clues to changing climate
June 26, 2015
By revisiting glaciers and coral reefs photographed years before, photographers harness the power of pictures and tell the story of an altered planet.
By David Arnold
The Daily Climate
One of the rewards of my climate work comes when I present my photo comparisons to high school students. I compare scenes of changes over the years to glaciers and hard coral reefs. I find older museum quality images, then return to the sites to reshoot the pictures as precisely as possible.
The reward comes about halfway through the presentation when I transition from ice to corals. First up is a 1995 shot of a resplendent elk horn coral located off St. Croix in the US Virgin Islands. Click and it dissolves into the gray boneyard you see today. Inevitably I hear feet shuffle and perhaps a gasp or muffled moan or two as if they have been sucker punched.
“YES!” I think to myself. Now I know these stewards of the future got it. Who knows? Maybe I even changed a life or three. And this gives me hope.
Such is the power of photographs.
My mission, and that of Double Exposure and its co-founder Gabriela Romanow, is to illustrate indisputably how the baseline is shifting above and below the waterline.
I return to duplicate the early work of others, striving for the same lighting conditions and camera angles, be my perches a mile high or 60 feet underwater. Double Exposure created a traveling exhibit of glacier comparisons that opened at the Museum of Science in Boston in 2008. We intend to do the same with corals. As the portfolio expands, I present the work in progress and I am always impressed how the coral images hurt most.
The glacier pictures from the Alps and Alaska are aerials that can encompass the area of a New England state. I’ve concluded the vertical distance offers the safety of emotional detachment. Bombardiers must feel the same way. But because of the quirky way that light behaves underwater, coral photography is done close up with wide-angle lenses. The relationship is far more intimate, in part because the coral polyp, which builds and lives in forests of calcium carbonate shell, is an animal.
They are not happy.
Hard corals are dying a death by one thousand cuts. Assailants range from local stresses such as shoreline pollution and overfishing to planetary scale climate-related assaults from heat shocks and acidification, which results from carbon dioxide uptake spurring decreasing ocean pH. (Eggshell, like hard coral, is made of calcium carbonate. To witness acidity at work, drop a morsel of eggshell in vinegar.)
More than 60 percent of the world’s reefs are in immediate and direct threat, according to the World Resources Institute, a global research organization. Almost 40 percent of hard corals may be too ill to recover. Out of sight, they may be out of mind. But coral decline is telling us something is very wrong with the water.
I often am re-shooting corals photographed by underwater pioneers from the pre-GPS era who never dreamed someone might want to retake their pictures. Frequently I am asked: “So how do you find these places again?”
The search started in 2010 one hundred miles inland. A central Maine resident had collected just about every issue of Skin Diver magazine printed between 1951 and 2002. My criteria were demanding. A candidate picture had to include a topographic feature to prove the comparison shot was legitimate. The photographer obviously had to still be alive. And he or she had to be willing to go through old slides, believe my project was worthwhile, and have the faintest idea where the picture was taken. The search continues. I probably bat .3 percent—one successful pairing per 300 pictures considered.
Luck helps. For example, one Steve Lucas of Siloam, Arkansas, invited me to his home four years ago to pore over old pictures. Into the late evening we poked through hundreds upon hundreds of slides looking for hard coral scenes that met my demands. Lucas, just 60 years old at the time, had not dived for many years because of diabetes he had had since birth. Nevertheless he could recall the dates, and sometimes the exact locations of pictures as he reveled in the memories they tapped.
One 1982 shot was of a mighty brain coral the size of a small car.
“Located off Key Largo. Must be one of the largest brain corals in the hemisphere,” Lucas said.
Back in the 1960s, someone had sunk a life-sized sculpture of Jesus off the Florida key to promote scuba tourism.
“Find the Jesus and swim about 50 feet in the direction of his raised left arm,” Lucas said.
Five days later he died.
Eventually I got to the Keys. Eventually I found Jesus and sighted down his extended left arm through the murky water and bingo, there was the coral behemoth precisely where Lucas said it would be. The monster was dead, its decaying surface is now the soft substrate into which species of soft corals root.
But as long as its carcass and those of a dozen others remain in my portfolio, they will remind me of the underwater pioneers, a coral world in stress, teenagers who understand, and the power of the photograph.
Photos: First comparison is large brain coral from Key Largo, Florida. Top photo from 1985, taken by Steve Lucas, and second photo taken by David Arnold in 2012.Second comparison is from Buck Island Reef National Monument in St. Croix. Left photo from 1995, taken by John Brooks (NPS), right photo taken by David Arnold in 2011.
Photojournalist David Arnold is a former staff reporter with the Boston Globe (25 years) and co founder of the website Double Exposure.
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