Greenland Caves: Travel time to warm Arctic

A 12-centimeter-thick sample from a cave in northeastern Greenland gives unique insights into the Arctic climate of more than 500,000 years ago. The geologist and cave scientist collected Dr. Gina Moseley is on a research trip in 2015 for her palaeoclimatic research in one of the world’s most sensitive areas of climate change. The cave is located 80 ° North 35 km from the coast and 60 km from the edge of the Greenland ice sheet. It was part of the Greenland Caves Project, funded by 59 different sponsors including the National Geographic Society. Moseley and her team are interested in the history of climate and environment captured by the unique cave deposit. “Mineral deposits formed in caves, called speleothems, include stalagmites and stalactites. In this case we analyzed rock deposits, which form deposits similar to a page from a thin water film “, explains Moseley. It is very special to find such an investment in the Arctic Arctic at all, the geologist continues: “Today this area is a polar desert and the ground is frozen due to climate. create this bedrock, the climate during which this period must have been warmer and wetter than today.The period between about 588,000 to 549,000 years before this time is thought to have been cool throughout the world compared to today. However, the growth of the speleothem at this time shows that the Arctic was remarkably warm “.

Gina Moseley therefore clarifies the regional heterogeneities that need to be considered when studying climate change specifically for future developments in a warmer world. “Our results from warmer and wetter Arctic support modeling show that there were regional heterogeneities and that the Arctic was irregularly warm due to the Earth ‘s orbital relationship with the sun at the time. These warmer temperatures reduced the amount of sea ice in the Arctic, thus providing ice-free open waters where moisture could be evacuated and transported to northeast Greenland ” , adds the geologist from the University of Innsbruck. The palaeoclimate plateau speleothem offers an opportunity to extend the knowledge of Greenland’s climate and irrigation situation in the past beyond the 128,000-year boundary of Greenland’s deep ice rocks. The team used innovative techniques such as uranium-thorium emission that are able to extend the timeline much further back. “Because Greenland’s ice sheets are inclined towards the last glacial period and hence the cold climate, the speleothem chart provides a good balance of warm weather in the past” , Moseley says. “The Arctic is warming at more than twice the global average. It is very important to understand how this sensitive part of the world responds in a warmer world.”

Gina Moseley highlighted the importance of caves in northeast Greenland back in 2008 when she did her PhD in Bristol, UK. In 2015, she led a five-part-funded tour of five fans. The journey was a challenge: The crew first tried to fly as far as they could, then crossed a 20 kilometer wide lake in a rubber dinghy and then had to walk for three days to get to the caves. This was the first time such climate records had been made from caves in the Arctic and Gina Moseley received the prestigious START Award from the Austrian Science Fund (FWF) for her research, which allowed her to do new research. start six years. project. In July 2019, Moseley and her team returned to the Greenland Caves Project to northeastern Greenland for a three-week tour.

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GE Moseley, RL Edwards, NS Lord, C. Spötl, H. Cheng: A speleothem record of a moderately wet mid-Pleistocene climate in northeastern Greenland. Sci.Adv. 2021, 7: eabe1260 DOI: 10.1126 / sciadv.abe1260

Connection: https: //www.doi.org /10.1126 /sciadv.abe1260

Greenland Caves Project: http: // www.greenlandcavesproject.org

Innsbruck Quaternary Research Group: https: //quaternary.uibk.ac.at /