They saddled heavy equipment and moved along its ridges pind, in search of information that has remained hidden for thousands of years at the bottom of alpine lakes. On the way they met blizzards, and in some places polar conditions. IN Gistova Grammos in some places a sheet of ice covered the water, fragile enough to support the weight of men and equipment, but at the same time strong enough to make navigation difficult. They sank a makeshift drill and collected cylindrical sediment samples. In this mud, they will find the remains of volcanic ash, layers of dust from the Sahara, as well as pollen, hoping to uncover the secrets of climatic conditions that existed thousands of years ago.

The field count was carried out at the end of May in Gistovo, as well as on the high mountain lakes Smolika and Astraka. It was carried out in the context international interdisciplinary program PalAeolus, which brings together experts from Greece and abroad to present the paleoclimate and atmospheric circulation in Southeast Europe. A few months ago, they climbed Mount Olympus and took pieces of ice from the Snow Hole Cave.

They followed a similar procedure, collecting deposits from Fanari lagoons in the Rhodopes and Korission lagoons in Corfu. Some samples have already been sent for analysis to laboratories in France, Romania and Greece. Depending on the dating of the material, the researchers will try to reconstruct the climate, ideally for the last 5,000 years. “We are trying to understand the natural rhythm of the climate by combining records, innovative for Greece, from the alpine zone and sediments deposited in coastal lagoons,” Tells geologist-researcher Michalis Stillas..

OUR Aurel Persoyu, a researcher at the Romanian Academy of Sciences, explains that their mission is to reconstruct wind dynamics in Southeast Europe. By seeing climate changes that have prevailed in past geological periods, they will be able to better understand how they have affected past societies and cultures, as well as better understand climate change.

In samples of bottom sediments collected by scientists, the remains of volcanic ash, layers of dust from the Sahara and pollen were found.

Sample selection

“Alpine lakes are a depositional environment and record everything” says geologist Christos Pennos. who participated in the study. As he explains, finding layers of dust from the Sahara in these samples is an important paleoclimate indicator that will show exactly how weather systems work. Also, the volcanic ash residue they will be looking for is an indicator that may help them try to date the samples. Since the catchment area of ​​the highland lakes is small, only an earthquake or a major landslide could have disturbed the sediments, otherwise it is assumed that sedimentation conditions were smooth over time. Analysis of the samples in a laboratory in France, which has relevant experience with paleo-earthquakes in Turkey, will show whether the samples have been disturbed.

For the needs of sampling in high mountain lakes, a small inflatable boat was used, to which two wooden platforms with a winch and drilling equipment were attached. A transparent tube for collecting sediment was immersed in the deepest part of a high mountain lake and carefully removed the dirt.

“Both when collecting samples in caves and in alpine lakes, teamwork is necessary,” says Persoyou. In Pindos, the researchers were supported by shelter residents who helped them every step of the way, volunteer climbers from Grevena, and members Project LimnADs, within which measurements are made for the needs of other scientific research. This cooperation, as well as the support of local authorities and representatives of local authorities in the Rhodope and Corfu lagoons, was one of the achievements of the study, as also pointed out by Michalis Stillas. For a person with his performances, who has visited the most remote corners of the world as part of climbing or scientific expeditions, the study of high-mountain lakes is a novelty, an opportunity to “know unexplored Greece”.