An Account of the Climate as Told by the Trees
Researchers at the GFZ German Research Centre for Geosciences in Potsdam, Germany are reconstructing temperature data from trees in Turkey to better define and understand the climactic conditions. Researchers have confidently chronicled a block of time that reflects the medieval warm period including a little ice age between the 16th and 19th centuries up to the transition into the more modern warm phase in the mountains near Antalya, the coastal Mediterranean coastal region of Turkey. Researchers led by Ingo Heinrich from the GFZ have studied this time series using carbon isotope ratios reflected in the tree rings of the region.
Researchers have long been dogged with reconciling the differences between various extreme locations including high mountain zones and high latitudes from different geographical locations. However stable carbon isotope ratios (13C/12C) are clearing up the puzzlement and opening the door for greater historical understanding of climate change.
Beyond simply counting the rings to determine a tree's age, researchers are able to discern the temperature and precipitation for any given year. Each ring is unique, some are thicker and some are thinner yielding more in depth questions. By extracting a sample wood core from the Juniperus excels, researchers microscopically analyzed the early and late wood cells and the "variability in wood density and resin channels as a result of drought stress."
Therefore each ring tells its own individual annual climactic story. For instance, for a year when the winter was particularly cold, cambium and leaves are more severely damaged extending the amount of time it takes to evolve into spring. This action leaves its mark in the form of the tree’s historic record for the annual temperature and precipitation calculator. Similarly, when spring temperatures are consistently low, photosynthesis is delayed effecting development of the cambium.
"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."
As climactic historians, trees therefore become good predictive recorders for the future.
Read more: GFZ German Research Centre for GeosciencesPhoto Credit: Ingo Heinrich