"If the area hadn't been covered by a glacier all these thousands of years, these tree remnants would never have made it. The finds yield information indicating that the 20th century was probably the warmest century in 7,000 years. The fact that the climate is so unique during the last century means that we must question whether this could be 100 percent the result of natural mechanisms," says Leif Kullman, professor of physical geography, who is directing the project.
Pines and birches grew on the site of the glacier during parts of or perhaps the entire period between 11,800 and 7,000 years ago. This is shown by carbon 14 dating of the remains of trees that have now been uncovered. During that period, the glacier did not continuously exist, and the climate was warmer than at any time afterward.
All in all, there are four finds, parts of birch and pine trunks, that have been uncovered under the shrinking glacier in the Lapland mountains. In most cases they are well preserved, but they are degrading rapidly as they come in contact with air and water. As early as 2003, tree remnants of a similar age were found in Sylarna, in Jämtland province. They have completely crumbled into dust at this point. The warmer climate during the last century, which is the reason the tree remnants have now seen the light of day, may therefore be unique in the perspective of many millennia.
The oldest tree, a pine, lived and died on the site of the Kårsa glacier around 12,000 years ago. The area is 400-450 meters above today's timberline. This discovery places the thawing of ice at the end of the latest ice age in an entirely new perspective.
"Previous research indicated that Lapland was covered with ice at this time. These finds show that the ice melted and life returned much earlier than we previously thought," says Leif Kullman.
The researchers are now continuing their examination of glaciers in northern Lapland and Västerbotten (West Bothnia). This ongoing research is part of a larger project that comprises glaciers throughout the entire range of mountains in Sweden. The project is funded by the Swedish Research Council and is directed by Professor Leif Kullman, Umeå University.
NASA looks to solar eclipse to help understand Earth's energy system
21.07.2017 | NASA/Goddard Space Flight Center
Scientists shed light on carbon's descent into the deep Earth
19.07.2017 | European Synchrotron Radiation Facility
Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.
For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...
What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.
To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...
The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....
A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...
Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision
Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...
21.07.2017 | Event News
19.07.2017 | Event News
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