An exactly dated time series of almost 900 year length was established, exhibiting the medieval warm period, the little ice age between the 16th and 19th century as well as the transition into the modern warm phase.
Moreover, Ingo Heinrich from the GFZ German Research Centre for Geosciences and colleagues revealed that the modern warming trend cannot be found in the new chronology.
"A comparison with seasonal meteorological data also demonstrates that at several places in the Mediterranean the winter and spring temperatures indicate long-term trends which are decreasing or at least not increasing", says Ingo Heinrich. "Our results stress the need for further research of the regional climate variations."
It seems that especially temperature reconstructions derived from extreme sites such as high mountain zones and high latitudes do not always correctly reflect the climate of the different geographical regions. The past temperature variations in the lowlands of central Europe and in the Mediterranean are not well understood yet. The analysis of carbon isotope ratios (13C/12C) in tree rings aims to close this research gap. By focusing on the months January to
May the researchers detected the period in which the trees shift from dormancy in late winter to re-activation of growth in early spring. The carbon isotope ratios measured in individual tree rings largely depends on the environmental conditions; thus, the varying tree-ring isotope values are good indicators for changes in the environment. The carbon isotope ratios in the trees from Turkey indicate a temperature sensitivity of the trees during late winter to early spring. In cold winters the cambium and the leaves are damaged more than usual and the following recovery in spring takes longer. Low spring temperatures further delay the photosynthesis or slow down the rate of photosynthesis, with negative effects on the cambial activity.
Ingo Heinrich, Ramzi Touchan, Isabel Dorado Liñán, Heinz Vos, Gerhard Helle: „Winter-to-spring temperature dynamics in Turkey derived from tree rings since AD 1125", Climate Dynamics, October 2013, Volume 41, Issue 7-8, pp 1685-1701, DOI 10.1007/s00382-013-1702-3
Pictures in a printable resolution can be found here: http://www.gfz-potsdam.de/medien-kommunikation/bildarchiv/klimaforschung/dendrochronologie/
F.Ossing | EurekAlert!
GPM sees deadly tornadic storms moving through US Southeast
01.12.2016 | NASA/Goddard Space Flight Center
Cyclic change within magma reservoirs significantly affects the explosivity of volcanic eruptions
30.11.2016 | Johannes Gutenberg-Universität Mainz
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy