CPD Climate of the Past Discussions CPD 1814-9359 Copernicus GmbH Göttingen, Germany 10.5194/cpd-4-1159-2008 Millennium-long summer temperature variations in the European Alps as reconstructed from tree rings Corona C. 1 Guiot J. 1 Edouard J. L. 2 Chalié F. 1 Büntgen U. 3 Nola P. 4 Urbinati C. 5 CEREGE, UMR 6635 CNRS/Aix-Marseille Univ., BP 80, 13545 Aix-en-provence cedex 4, France IMEP, UMR 6116 CNRS/Aix-Marseille Univ., BP 80, 13545 Aix-en-provence cedex 4, France Swiss Federal Research Institute WSL, Zuercherstrasse 111, 8903 Birmensdorf, Switzerland Università degli Studi di Pavia, Dip. Ecologia del Territorio a degli Ambienti Terrestri, Via S. Epifanio, 14, 27100 Pavia, Italy Università Politecnica delle Marche, Dip. SAPROV, Forest Ecology and Management, Via Brecce Bianche, 60131 Ancona, Italy 07 10 2008 4 5 1159 1201 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.clim-past-discuss.net/4/1159/2008/cpd-4-1159-2008.html The full text article is available as a PDF file from http://www.clim-past-discuss.net/4/1159/2008/cpd-4-1159-2008.pdf

This paper presents a reconstruction of the summer temperatures over the Greater Alpine Region (44.05°–47.41° N, 6.43°–13° E) during the last millennium based on a network of 36 multi-centennial larch and stone pine chronologies. Tree ring series are standardized using an Adaptative Regional Growth Curve, which attempts to remove the age effect from the low frequency variations in the series. The proxies are calibrated using the June to August mean temperatures from the HISTALP high-elevation temperature time series spanning the 1818–2003. The method combines an analogue technique, which is able to extend the too short tree-ring series, an artificial neural network technique for an optimal non-linear calibration including a bootstrap technique for calculating error assessment on the reconstruction. About 50% of the temperature variance is reconstructed. Low-elevation instrumental data back to 1760 compared to their instrumental target data reveal divergence between (warmer) early instrumental measurements and (colder) proxy estimates. The proxy record indicates cool conditions, from the mid-11th century to the mid-12th century, related to the Oort solar minimum followed by a short Medieval Warm Period (1200–1420). The Little Ice Age (1420–1830) appears particularly cold between 1420 and 1820 with summers are 0.8°C cooler than the 1901–2000 period. The new record suggests that the persistency of the late 20th century warming trend is unprecedented. It also reveals significant similarities with other alpine reconstructions.

 References Anderson, T. L., Charlson, R. J., Schwartz, S. E., Knutti, R., Boucher, O., Rodhe, H., and Heintzenberg, J.: Climate forcing by aerosols–A hazy picture, Science, 302, 1679–1681, 2003. Auer, I., Böhm, R., Jurkovi\'c, A., Lipa, W., Orlik, A., Potzmann, R., Schöner, W., Ungersböck, M., Matulla, C., Briffa, K., Jones, P., Efthymiadis, D., Brunetti, M., Nanni, T., Maugeri, M., Mercalli, L., Mestre, O., Moisselin, J.-M., Begert, M., Müller-Westermeier, G., Kveton, V., Bochnicek, O., Stastny, P., Lapin, M., Szalai, S., Szentimrey, T., Cegnar, T., Dolinar, M., Gajic-Capka, M., Zaninovic, K., Majstorovic, Z., and Nieplova, E.: HISTALP – historical instrumental climatological surface time series of the Greater Alpine Region, Int. J. Climatol., 27, 17–46, 2007. Bard, E., Raisbeck, G., Yiou, F., and Jouzel, J.: Comment on "Solar activity during the last 1000 yr inferred from radionuclide records" by Muscheler et al (2007), Quaternary Sci. Rev., 26, 2301–2308, 2007. Becker, M.: The role of climate on present and past vitality of silver fir in the Vosges mountains of northern France, Can. J. Forest Res., 19, 1110–1117, 1989. Begert, M., Schlegel, T., and Kirchhofer, W.: Homogeneous temperature and precipitation series of Switzerland for 1864 to 2000, Int. J. Climatol., 25, 65–80, 2005. Böhm, R., Auer, L., Brunetti, M., Maugeri, M., Nanni, D., and Schöner, W.: Regional temperature variability in the European Alps: 1760–1998 from homogenized instrumental time series, Int. J. Climatol., 21, 1779–1801, 2001. Brázdil, R., Pfister, C., Wanner, H., Von Storch, H., and Luterbacher, J.: Historical climatology in Europe–State of the art, Climatic Change, 70, 363–430, 2005. Briffa, K. R., Jones, P. D., Bartholin, T. S., Eckstein, D., Schweingruber, F. H., Karlén, W., Zetterberg, P., and Eronen, M.: Fennoscandian summers from AD 500 – temperature-changes on short and long timescales, Clim. Dynam., 7, 111–119, 1992. Briffa, K.R., Schweingruber, F. H., Jones, P. D., Osborn, T. J., Harris, I. C., Shiyatov, S. G., Vaganov, E. A., and Grudd, H.: "Trees tell of past climates: but are they speaking less clearly today?", Philos. T. Roy. Soc. B, 353, 65–73, 1998. Briffa, K. R., Osborn, T. J., Schweingruber, F. H., Harris, I. C., Jones, P. D., Shiyatov, S. G., and Vaganov, E. A.: Low-frequency temperature variations from a northern tree-ring density network, J. Geophys. Res., 106, 2929–2941, 2001. Brunetti, M., Maugeri, M., Monti, F., and Nanni, T.: Temperature and precipitation variability in Italy in the last two centuries from homogenised instrumental time series, Int. J. Climatol., 26, 345–381, 2006. Büntgen, U., Esper, J., Frank, D. C., Nicolussi, K., and Schmidhalter, M.: A 1052-year tree-ring proxy of Alpine summer temperatures, Clim. Dynam., 25, 141–153, 2005. Büntgen, U., Frank, D. C., Nievergelt, D., and Esper, J.: Summer temperature variations in the European Alps, AD 755-2004, J. Climate, 19, 5606–5623, 2006a. Büntgen, U., Bellwald, I., Kalbermatten, H., Schmidhalter, M., Freund, H., Frank, D. C., Bellwald, W., Neuwirth, B., Nüsser, M., and Esper, J.: 700 years of settlement and building history in the Lötschental/Switzerland, Erdkunde, 60/2, 96–112, 2006b. Büntgen, U., Frank, D., Wilson, R., and Esper, J.: A test for tree-ring divergence in the European Alps, Glob. Change Biol., 14, 2443–2453, 2008. Carrer, M. and Urbinati, C.: Age-dependent tree-ring growth responses to climate in Larix decidua and Pinus cembra, Ecology, 85, 730–740, 2004. Carrer, M. and Urbinati, C.: Long-term change in the sensitivity of treering growth to climate forcing in Larix decidua, New Phytol., 170, 861–872, 2006. Casty, C., Wanner, H., Luterbacher, J., Esper, J. and Böhm, R.: Temperature and precipitation variability in the European Alps since 1500, Int. J. Climatol., 25, 1855–1880, 2005. Chuine, I., Yiou, P., Viovy, N., Seguin, B., Daux, V., and LeRoy Ladurie, E.: Grape ripening as an indicator of past climate, Nature, 432, 289–290, 2004. Cook, E. and Kairiukstis, L.: Methods of dendrochronology, Kluwer, Dordrecht, 1990. Cook, E. R., Briffa, K. R., and Jones, P. D.: Spatial regression methods in dendroclimatology: A review and comparison of two techniques, Int. J. Climatol., 14, 379–402, 1994. Cook, E. R., D'Arrigo, R. D., and Mann, M. E.: A well-verified, multiproxy reconstruction of the Winter North Atlantic Oscillation Index since A.D. 1400, J. Climate, 15, 1754–1764, 2002. Crowley, T. J.: Causes of climate change over the past 1000 years, Science, 295, 270–277, 2000. D'Arrigo, R., Wilson, R., and Jacoby, G.: On the long-term context for late twentieth century warming, J. Geophys. Res., 111, D03103, doi:10.1029/2005JD006352, 2006. Dai, J., Mosley-Thompson, E., and Thompson, L. G.: Ice core evidence for an explosive tropical volcanic eruption 6 years preceding Tambora, J. Geophys. Res., 96, 17 361–17 366, 1991. Eddy, J. A.: The maunder minimum, Science, 192, 1189–1202, 1976. Efron, B.: Bootstrap methods: another look at the jackknife, The Annals of Statistics, 7, 1–26, 1979. Esper, J., Cook, E. R., and Schweingruber, F. H.: Low-frequency signals in long tree-ring chronologies for reconstructing past temperature variability, Science, 295, 2250–2253, 2002. Esper, J., Niederer, R., Bebi, P., and Frank, D: Climate signal age effects –Evidence from young and old trees in the Swiss Engadin, Forest Ecol. Manag., 255, 3783–3789, 2008. Etien, N., Daux, V., Masson-Delmotte, V., Stievenard, M., Bernard, V., Durost, S., Guillemin, M. T., Mestre, O., and Pierre, M.: A bi-proxy reconstruction of Fontainebleau (France) growing season temperature from A.D. 1596 to 2000, Clim. Past, 4, 91–106, 2008. Folland, C.K., Rayner, N.A., Brown, S.J., Smith, T.M., Shen, S.S.P., Parker, D.E., Macadam, I., Jones, P.D., Jones, R.N., Nicholls, N., and Sexton, D.M.H.: Global temperature change and its uncertainties since 1861, J. Geophys. Res., 28, 2621–2624, 2001. Frank, D. and Esper, J.: Temperature reconstructions and comparisons with instrumental data from a tree-ring network for the European Alps, Int. J. Climatol., 25, 1437–1454, 2005. Frank, D., Büntgen, U., Böhm, R., Maugeri, M., and Esper, J.: Warmer early instrumental measurements versus colder reconstructed temperatures: shooting at a moving target, Quaternary Sci. Rev., 28, 3298–3310, 2007a. Frank, D., Esper, J., and Cook, E. R.: Adjustment for proxy number and coherence in a large-scale temperature reconstruction, Geophys. Res., 34, L16709, doi:10.1029/2007GL030571, 2007b. Fritts, H. C.: Tree Rings and Climate, Academic Press, 1976. Grove, J. M.: The Little Ice Age, Methuen and Co., London, New York, 1988. Guiot, J.: Methods of calibration, verification and reconstruction, in: Methods of denrochronology, application in the environmental sciences edited by: Cook, E. and Kairiukstis, L., Dordrecht, International Institute for Applied Systems Analysis, Kluwer Academy Publications, 163–217, 1990. Guiot, J., Nicault, A., Rathgeber, C., Edouard, J.-L., Guibal, F., Pichard, G., and Till, C.: Last-millennium summer-temperature variations in western Europe based on proxy data, The Holocene, 15, 489–500, 2005. Harrington, C. D.: The Year without a Summer? World Climate in 1816, Canadian Museum of Nature, Ottawa, 1992. Holzhauser, H., Magny, M., and Zumbühl, H. J.: Glacier and lake-level variations in west-central Europe over the last 3500 years, The Holocene, 15, 789–801, 2005. Hughes, M. K. and Diaz, H. F.: Was there a "Medieval Warm Period" and if so, where and when?, Climatic Change, 26, 109–142, 1994. Jones, P. D., Osborn, T. J., and Briffa, K. R.: The evolution of climate over the last millennium, Science, 292, 662–666, 2001. Jones, P. D. and Mann, M. E.: Climate over past millennia, Rev. Geophys., 42, RG2002, doi:10.1029/2003RG000143, 2004. Lamb, H. H.: Climate: present, past and future, London: Methuen, 1976. LeRoy Ladurie, E.: Histoire humaine et comparée du climat, Vol 1: Canicules et glaciers XIII–XVIII siècles, Fayard, Paris, 2004. Luterbacher, J., Rickli, R., Xoplaki, E., Tinguely, C., Beck, C., Pfister, C., and Wanner, H.: The Late Maunder Minimum (1675–1715) – A key period for studying decadal scale climate change in Europe, Climatic Change, 49, 441–462, 2001. Luterbacher, J., Xoplaki, E., Dietrich, D., Jones, P. D., Davies, T. D., Portis, D., Gonzalez-Rouco, J. F., von Storch, H., Gyalistras, D., Casty, C., and Wanner, H.: Extending North Atlantic Oscillation reconstructions back to 1500, Atmos. Sci. Lett., 2, 114–124, 2002. Luterbacher, J., Dietrich, D., Xoplaki, E., Grosjean, M., and Wanner, H.: European seasonal and annual temperature variability, trends, and extremes since 1500, Science, 303, 1499–1504, 2004. Luterbacher, J., Dietrich, D., Xoplaki, E., Grosjean, M., and Wanner, H.: European Seasonal Temperature Reconstructions. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2006-060, NOAA/NCDC Paleoclimatology Program, Boulder CO, USA, 2006. Mangini, A., Spoetl, C., and Verdes, P.: Reconstruction of temperature in the Central Alps during the past 2000 year from a d18O stalagmite record, Earth Planet. Sc. Lett., 235, 741–751, 2005. Mann, M. E., Bradley, R. S., and Hughes, M. K.: Northern Hemisphere temperatures during the past millennium: inferences, uncertainties, and limitations, Geophys. Res. Lett., 26, 759–62, 1999. Mann, M. E., Gille, E., Bradley, R. S., Hughes, M. K., Overpeck, J. T., Keimig, F. T., and Gross, W.: Global temperature patterns in past centuries: an interactive presentation, Earth Interactions, 4, 1–29, 2000. Mann, M. E. and Jones, P. D.: Global Surface Temperatures over the Past Two Millennia, Geophys. Res. Lett., 30, 1820, doi:10.1029/2003GL017814, 2003. Matulla, C., Auer, I., Böhm, R., Ungersböck, M., Schöner, W., Wagner, S., and Zorita, E.: Outstanding past decadal-scale climate events in the Greater Alpine region analysed by 250 years data and model runs. GKSS-Report 2005/4. GKSS Forschungszentrum in der Helmholtz Gemeinschaft, Geesthacht, 2005. Meehl, G. A., Washington, W. M., Wigley, T. M. L., Arblaster, J. M., and Dai, A.: Solar and greenhouse gas forcing and climate response in the twentieth century, J. Climate, 16, 426–444, 2003. Moberg, A., Alexandersson, H., Bergström, H., and Jones, P.D.: Were Southern Swedish summer temperatures before 1860 as warm as measured? Int. J. Climatol., 23, 1495–1521, 2003. Moberg, A.D., Sonechkin, M., Holmgren, K., Datsenko, N.M., and Karlen, W.: Highly variable Northern Hemisphere temperatures reconstructed from low- and high-resolution proxy data, Nature, 433, 613–617, 2005. Mitchell, T.D., Hulme, M., and New, M.: Climate data for political areas, Area, 34, 109–112, 2002. Mitchell, T.D. and Jones, P.: An improved method of constructing a database of monthly climate observations and associated high-resolution grids, Int. J. Climatol., 25, 693–712, 2005. New, M., Hulme. M., Jones, P.D.: Representing twentieth-century space – time climate variability. Part II: development of 1901 – 96 monthly grids of terrestrial surface climate, J. Climate, 13, 2217–2238, 2000. Ni, F., Cavazos, T., Hughes, M. K., Combrie, A., and Funkhouser, G.: Cool-season precipitation in the Southwestern USA since AD 1000: comparison of linear and non linear techniques for reconstruction, Int. J. Climatol., 22, 1645–1662, 2002. Nicault, A., Guiot, J., Edouard, J.-L., and Brewer, S.: Preserving long-term fluctuations in standardization of tree-ring series by the Adaptative Regional Growth Curve (ARGC), Dendrochronologia, in press, 2008a. Nicault, A., Alleaume, S., Brewer, S., Carrer, M., Nola, P., and Guiot, J.: Mediterranean drought fluctuation during the last 500 years based on tree-ring data, Clim. Dynam., 31, 227–245, 2008b. Oerlemans, J.: Extracting a climate signal from 169 glacier records, Science, 308, 675–677, 2005. Oppenheimer, C.: Climatic, environmental and human consequences of the largest known historic eruption: Tambora volcano (Indonesia) 1815, Prog. Phys. Geog., 27, 230–259, 2003. Pauling, A., Luterbacher, J., Casty, C., and Wanner, H.: Five hundred years of gridded high-resolution precipitation reconstructions over Europe and the connection to large-scale circulation, Clim. Dynam., 26, 387–405, 2006. Pfister, C.: Monthly temperature and precipitation patterns in Central Europe from 1525 to the present. A methodology for quantifying man made evidence on weather and climate, in: Climate since 1500 A.D., edited by: Bradley R. S. and Jones, P. D., London, 118–143, 1992. Pfister, C., Kington, J., Kleinlogel, G., Schuele, H., and Siffert, E.: The creation of high-resolution spatio-temporal reconstructions of past climate from direct meteorological observations and proxy data, Methodological considerations and results, in: Climate in Europe 1675–1715, edited by: Frenzel, B., Pfister C., and Glaeser, B., 1994. Pfister, C.: Wetternachhersage, 500 Jahre Klimavariationen und Naturkatastrophen 1496–1995, Haupt Verlag, 1999. Rathgeber, C., Guiot, J., Roche, P., and Tessier, L.: Augmentation de productivité du chêne pubescent en région méditerranéenne française, Ann. Sci. Forest., 56, 201–209, 1999. Richman, M. B.: Rotation of principal components, J. Climatol., 6, 293–335, 1986. Robock, A.: Review of year without a summer? World climate in 1816, Climatic Change, 26, 105–108, 1994. Shindell, D. T., Schmidt, G. A., Mann, M. E., Rind, D., and Waple, A.: Solar forcing of regional climate change during the Maunder Minimum, Science, 294, 2149–2152, 2001. Sigurdsson, H. and Carey, S.: Plinian and co-ignimbrite tephra fall from the 1815 eruption of Tambora volcano, B. Volcanol., 51, 243–270, 1989. Wanner, H., Pfister, C., Brazdil, R., Frich, P., and Frydendah, K.: Wintertime European circulation patterns during the late Maunder minimum cooling period [1675-1704], Theor. Appl. Climatol., 51, 167–175, 1995. Wigley, T. M. L., Briffa, K.R., and Jones, P.D.: On the average of value of correlated time series, with applications in dendroclimatology and hydrometeorology, J. Clim. Appl. Meteorol., 23, 201–213, 1984. Woodhouse, C. A.: Artificial neural networks and dendroclimatic reconstructions: an example from the Front Range, Colorado, USA, The Holocene, 9, 521–29, 1999. Xoplaki, E., Luterbacher, J., Paeth, H., Dietrich, D., Steiner, N., Grosjean, M., and Wanner, H.: European spring and autumn temperature variability and change of extremes over the last half millennium, Geophys. Res. Lett., 32, L15713, doi:10.1029/2005GL023424, 2005. Zumbühl, H. J., Steiner, D., and Nussbaumer, S. U.: 19th century glacier representations and fluctuations in the central and western European Alps: an interdisciplinary approach, Global Planet. Change., 60, 42–57, 2008.