A hidden Arctic cave holds secrets of our past and future

Mosley’s love When she was 12, Caves went on a family camping trip to Cheddar, Somerset. She first ventured into the murky, labyrinthine bottom of the Earth’s crust when the opportunity arose for a guided tour of some local caves. Crawling around in the muck, she was instantly hooked: she began saving money from the paper wheels so that on a future holiday to Somerset she could disappear into those caves again. “I absolutely love it,” Mosley said. “Other people might feel this way if they go to Venice, wandering the alleys and wondering what’s around the corner – you know, that excitement. I get it when I’m underground.”

A few years later, she began studying for a PhD in paleoclimatology, which combined two of her interests: spelunking and climate change. Caves are valuable in climate studies because many contain speleothems: a collective name for geological features formed by mineral deposits that form stalagmites, stalactites, and flowstones that hang from the cave ceiling, or resemble anthills The same rises from the ground. Over thousands of years, caverns have grown slowly as water from the outside gradually trickles into the roof of the cave. Deposits of the mineral calcite form the physical structure, forming individual hair-thin layers over time, somewhat like the growth rings of a tree. “Each drop of water carries a chemical signature that tells us about the processes that occurred on the surface as it was deposited,” Mosley explains. Calcite, oxygen, carbon, and even traces of soil, pollen, and vegetation trapped within it, come together to build a picture of past environments: the amount of carbon dioxide in the atmosphere, temperature, rainfall, and even the habitat surrounding the cave.

At the same time, the caves themselves preserve these valuable records to a high degree, making them a porthole into the past. “[Caves are] It is closely connected to the surface environment and is also well protected from the influence of the surface environment. “That means they’re sitting beneath the surface, silently recording changes that have occurred over hundreds of thousands or even millions of years,” Mosley said. Such stable environments can produce a largely complete, long-term detailed record of past climate . Compared to other climate archives, for example ocean sediments may be more susceptible to disturbance by animals, or ice cores that melt as temperatures rise.”[Speleothems] said Christopher Day, an isotope geochemist and paleoclimatologist at the University of Oxford who was not involved in Mosley’s study.

Advances in uranium-thorium radiometric dating techniques used to analyze caves now allow researchers to date individual rock formations down to a precision of about 20 years. Combined with the environmental information they contain, “we can tell with great certainty when something happens,” Mosley said. She is careful to emphasize that caves are only a small part of the bigger picture when it comes to climate records, but because they are so widely distributed across the planet, their cavities can help fill gaps where other archival measures do not exist. At the same time, their detailed records help build a richer global picture of past environments. “You can gradually work towards showing what the environment looks like on a global scale, but using information that is specific to each region,” Day said. This helps researchers discover broad climate trends and compare differences and relationships between regions, he explained.

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