Research Overview:
The Taymir Peninsula of northern Siberia (see map)is home to the world's northernmost trees. These trees, growing at the latitudinal treeline are sensitive to temperatures and provide valuable data on environmental and climatic processes along the Arctic. By looking at chronologies of annual ring-width and density variations, we are using these trees to reconstruct temperatures over the past centuries, or even millenia. These temperature records provide a long term perspective on climate variability and are important for understanding the climate system. These records are also important for addressing issues and providing context to answer questions on anthopogenic global warming and human impact on the environment.
Some of our major objectives are:
1) To develop long chronologies of tree growth from living trees and extend these records by incorporating dead trees that have remained preserved in the cold arctic air, by being buried in permafrost or alluvial deposits, or submerged in lakes and rivers.2) To obtain records from many different sites to learn more about differences in tree response at these sites. Also, by looking at different species we hope to learn about different 'seasonal windows' of tree response.
3) To investigate the shift in the way trees have been responding to temperature that has been observed within the 30 years.
Research Tidbits:
1) Several chronologies are in the final stages of development along the Kotuikan River. These include deciduous Dahurian larch chronologies, and an evergreen Siberian spruce site. We anticipate the evergreen and deciduous species will be influenced by different 'seasonal windows'.A photo of a Dahurian larch cross section that was preserved in permafrost shows how slowly trees grow in this extreme northern environment.
2)We are making significant progess in building an annually resolved long chronology of tree growth at the Lukunska River site. Currently we have a series composed of living and relict Dahurian larch which extends back to 1130 AD, and are still trying to incorporate more subfossil and submerged samples. A photo of Gordon Jacoby shows the joys of obtaining submerged samples.
3) In the recent Jacoby et al. (2000) paper a regional reconstruction of May- September temperatures was made by using chronologies from 4 different sites. This reconstruction shows the very cold 19th century as well as the unusually warm 20th century.
4) Here is Neil Pederson displaying a bunch of samples cut from dead trees during the 1999 field season. These helped to extend our record at the Lukunska River site.
Recent publications about our work in Siberia:
1) Jacoby, G.C., N.V. Lovelius, O.I. Shumilov, O.M.Raspopov, J.M. Karbainov, and D.C. Frank, 2000, Long-term temperature trends and tree growth in the Taymir region of northern Siberia, Quaternary Research , 53, 312-318.
2) D'Arrigo, R.D., C.M. Malmstrom, G.C. Jacoby, S.O. Los, and D.E. Bunker, 2000, Using tree rings to test NDVI-based estimates of forest production, International Journal of Remote Sensing, (in press).
3) Frank, D.C., G.C. Jacoby, N.K. Davi, J.M. Karbainov, I.J. Kirtsidely, N. Pederson, O.M Raspopov, and O.I. Shumilov, 2000, Long-term larch derived temperature reconstruction from the Taymir peninsula, northern Siberia, International Conference on Dendrochronology for the Third Millennium, 2-7 April, 2000, Mendoza Argentina, Abstract with Programs, p.124.
4) Jacoby, G.C., R.D. D'Arrigo, and G.P. Juday, 1999, Tree-ring indicators of climatic change at northern latitudes, World Resources Review (11) 1, 21-29.
5) D'Arrigo, R., G. Jacoby, M. Free, and A. Robock, 1999, Northern hemisphere temperature variability for the past three centuries: tree-ring and model estimates, Climatic Change, 42, 663-675.
Personnel:
Dr. Gordon Jacoby, David Frank, Nicole Davi & Neil Pederson
Tree-Ring Lab, Lamont-Doherty Earth Observatory
Dr. Nikolai Lovelius
Botanic Institute of RAS
Prof. Oleg M. Raspopov
S. Petersburg Filial Institute of Terrestrial Magnetism, Ionosphere and Radiowaves Propagation SPbF IZMIRAN
Dr. Oleg I. Shumilov
High-Latitude Geophysical Lab. of SPbF IZMIRAN
Dr. Irina Ju. Kirtsidely
Botanical Institute RAS
Some Related Tree-Ring Lab Pages
| Boreal Forest Studies | Research in Mongolia |
Acknowledgements:
This material is based upon work supported by the National Science Foundation under Grant No. ATM98-09230 and by the North Atlantic Treaty Organization (NATO)
Any opinions, findings and conclusions or recomendations expressed in this material are those of the authors(s) and do not neccessarily reflect the views of the National Science Foundation (NSF)
Voice: (845) 365-8517, Fax: (845) 365-8152
Last Updated: June, 2000 (David)