The Climate Underground
THE ENTRANCE TO TITAN CAVE, east of Cody, Wyoming, is hidden on a wide plateau of sagebrush and juniper surrounded by ridge after ridge of craggy mountains. The distant peaks were snowy when I visited in late May, and a slight breeze stirred the desert air. I was with a group of five scientists whose research would take them underground into a grand chamber of stalagmites and stalactites, or speleothems, formations created by occasional drips of water starting hundreds of thousands of years ago or more. They fill Titan’s main room with delicate flutes and hulking, lopsided formations that look like something from a sea floor. Hundreds of broken pieces lie scattered around the cave, like piles of bones, while others stand tall, rough stone pillars connecting the floor to the ceiling.
The night before our descent, Jessica Oster, an associate professor of earth and environmental sciences at Vanderbilt University, and one of her graduate students huddled around a laptop open on the bed of the student’s motel room in Cody, trying to recall the route to Titan’s location on a Bureau of Land Management parcel. Oster, kneeling in front of the computer, sighed. “I’m less worried about this part and more worried about the door,” she said, anxiety bringing a lilt to her voice. “I just want everyone to have fun.” After a moment, she added, “And stay alive.”
The scientists had visited the cave before, but never without a BLM employee guarding its entrance. The door is a heavy metal panel, a couple of feet across, that’s supposed to be kept locked. But the BLM cave coordinator would be at an all-day helicopter training, so he’d dropped off a key to the door — along with a sledgehammer. We were on our own.
Lilacs were just starting to bloom in the small towns we drove through on our way to Titan. The scientists pointed out different rock layers through the windows: red siltstone and shale, with names like the Chugwater and Goose Egg formations. Eventually, we reached the top of the plateau, and parked a few yards from the cave mouth.
The researchers stepped around their vehicle and each other, packing up gear, pulling on boots, duct-taping headlamps to helmets. Anticipation combined with the knowledge that we weren’t supposed to pee underground meant we took turns ducking behind the scrubby bushes. Earlier, Cameron de Wet, a graduate students, had printed out tiny paper maps of the cave for each of us. Now he carefully adjusted items in one of two blocky blue rectangular bags that held the pieces of a scientific instrument — the reason for the trip.
One of the scientists had analyzed calcium carbonate formations from Titan Cave — stalagmites, the pillars that grow from cave floors — and found that some were around 400,000 years old or older. Stalagmites accumulate from the bottom up, preserving the chemical composition of the water that forms them as it drips from the cave ceiling, often from the tip of what looks like a stone icicle — a stalactite. Researchers can use those chemical recordings to infer what the climate was like when the stalagmites formed. But working all this out is complex, and requires understanding the present-day chemical relationships among rainfall on the surface, the
