European Alps 944 Year Multiproxy Summer Temperature Reconstructions Trachsel, M.; Kamenik, C.; Grosjean, M.; McCarroll, D.; Moberg, A.; Brázdil, R.; Büntgen, U.; Dobrovolný, P.; Esper, J.; Frank, D.C.; Friedrich, M.; Glaser, R.; Larocque-Tobler, I.; Nicolussi, K.; Riemann, D. Trachsel, M. Kamenik, C. Grosjean, M. McCarroll, D. Moberg, A. Brázdil, R. Büntgen, U. Dobrovolný, P. Esper, J. Frank, D.C. Friedrich, M. Glaser, R. Larocque-Tobler, I. Nicolussi, K. Riemann, D. Air Temperature Reconstruction Little Ice Age (LIA) Medieval Climate Anomaly (MCA) earth science/paleoclimate/climate reconstructions|tree ring (temperature,null,null,degree Celsius,Jun-Aug,climate reconstructions|tree ring,anomalized|filtered,null,N,reference period 1901-2000 AD; gaussian filtered) earth science/paleoclimate/climate reconstructions|paleolimnology|tree ring (temperature,null,null,degree Celsius,Jun-Aug,climate reconstructions|paleolimnology|tree ring,anomalized|filtered,null,N,reference period 1901-2000 AD; gaussian filtered) earth science/paleoclimate/climate reconstructions|paleolimnology|tree ring (temperature,null,null,degree Celsius,Jun-Aug,climate reconstructions|paleolimnology|tree ring,anomalized|filtered,regression analysis,N,reference period 1901-2000 AD; gaussian filtered; partial least squares regression) earth science/paleoclimate/climate reconstructions|paleolimnology|tree ring (age,null,null,year Common Era,null,climate reconstructions|paleolimnology|tree ring,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleolimnology|tree ring (temperature,null,null,degree Celsius,Jun-Aug,climate reconstructions|paleolimnology|tree ring,anomalized,regression analysis,N,reference period 1901-2000 AD; partial least squares regression) earth science/paleoclimate/climate reconstructions|tree ring (temperature,null,null,degree Celsius,Jun-Aug,climate reconstructions|tree ring,anomalized,regression analysis,N,reference period 1901-2000 AD; partial least squares regression) earth science/paleoclimate/climate reconstructions|tree ring (temperature,null,null,degree Celsius,Jun-Aug,climate reconstructions|tree ring,anomalized,null,N,reference period 1901-2000 AD) earth science/paleoclimate/climate reconstructions|tree ring (temperature,null,null,degree Celsius,Jun-Aug,climate reconstructions|tree ring,anomalized|filtered,regression analysis,N,reference period 1901-2000 AD; gaussian filtered; partial least squares regression) earth science/paleoclimate/climate reconstructions|paleolimnology|tree ring (temperature,null,null,degree Celsius,Jun-Aug,climate reconstructions|paleolimnology|tree ring,anomalized,null,N,reference period 1901-2000 AD) earth science/paleoclimate/climate reconstructions|paleolimnology|tree ring (temperature,null,null,degree Celsius,Jun-Aug,climate reconstructions|paleolimnology|tree ring,anomalized|averaged,null,N,reference period 1901-2000 AD) earth science/paleoclimate/climate reconstructions|paleolimnology|tree ring (temperature,null,null,degree Celsius,Jun-Aug,climate reconstructions|paleolimnology|tree ring,anomalized|averaged|filtered,null,N,reference period 1901-2000 AD; gaussian filtered) earth science/paleoclimate/reconstructions (Greater Alpine Region>LATITUDE >LONGITUDE ) We present a multi-archive, multi-proxy summer temperature reconstruction for the European Alps covering the period AD 1053-1996 using tree-ring and lake sediment data. The new reconstruction is based on nine different calibration approaches and errors were estimated conservatively. Summer temperatures of the last millennium are characterised by two warm (AD 1053-1171 and 1823-1996) and two cold phases (AD 1172-1379 and 1573-1822). Highest pre-industrial summer temperatures of the 12th century were 0.3°C warmer than the 20th century mean but 0.35°C colder than proxy derived temperatures at the end of the 20th century. The lowest temperatures at the end of the 16th century were ~1°C lower than the 20th century mean. STUDY NOTES: Multiproxy summer temperature reconstructions for the European Alps covering AD 1053-1996, based on tree-ring and lake sediment data. Eight treering and lake sediment based proxies, from four different locations in the Greater Alpine Region, were utilized in the reconstructions. Nine different calibration approaches were used to reconstruct summer temperatures. The calibration period is 1760-1996, on JJA mean temperatures averaged over the region 43-49°N and 4-19°E, using gridded temperature data. Greater Alpine Region: ~43-49°N, ~4-19°E Table 1 Proxies used in this study. 1 Late-wood density Lötschental (Switzerland) Büntgen et al., 2006 755-2004 Larix decidua All 2 Late-wood density Tyrol (Austria) Esper et al., 2007 1053-2003 Picea abies All 3 Tree-ring width Tyrol (Austria) Büntgen et al., 2005 848-1997 Pinus cembra All 4 Tree-ring width Alpine Arc Büntgen et al., 2009 951-2004 Larix decidua All 5 Tree-ring width Dachstein (Austria) Friedrich unpubl. 900-1996 Larix decidua All 6 Blue Intensity Dachstein (Austria) Friedrich unpubl. 813-1996 Conifer 1-31; 1-11; 11-31; 31-51 7 Chironomids Silvaplana (Switzerland) Larocque-Tobler et al., 2010 1007-2002 11-31; 31-51; >31; >51 8 Biogenic Silica Silvaplana (Switzerland) Blass 2007;Trachsel 2010 1181-1949 11-31; 31-51 Table 3 Numerical methods and error statistics of the nine calibration/reconstruction variants. Name #Freq.Bands Data Included #DataSeries Calib.Period RMSEP°C r2 Amp/RMSEP ReconPeriod Freq.band and stat.method w/Fig.3 colour code Variant 1 2 Tree-rings 1-6 1776-1981 0.76 0.61 6.44 1068-1981 1-31 (PLSR, Fig. 4d: green) and >31 (PLSR, Fig. 4e: blue); Fig. 4h: grey Variant 2 2 Tree-rings and lake 1-7 1776-1981 0.78 0.62 6.19 1068-1981 1-31 (PLSR, Fig. 4d: black) and >31 (PLSR, Fig. 4e black); Fig. 4h: black Variant 3 2 Tree-rings 1-6 1761-1996 0.8 0.61 6.26 1053-1996 1-31 (PLSR, Fig. 4d: green) and >31 (PLSR, Fig. 4e cyan); Fig. 4h: cyan Variant 4 2 Tree-rings and lake 1-7 1761-1996 0.76 0.62 6.74 1053-1996 1-31 (PLSR, Fig. 4d: orange) and >31 (PLSR, Fig. 4e: orange); Fig. 4h: brown Variant 5 2 Tree-rings 1-6 1761-1996 0.8 0.61 6.61 1053-1996 1-31 (PLSR, var stab, Fig. 4d: blue) and >31 (PLSR, Fig. 4e: green); Fig. 4h: pink Variant 6 2 Tree-rings 1-6 1761-1996 0.78 0.58 7.18 1053-1996 1-31 (CPS, var stab, Fig. 4d: cyan) and >31 (PLSR, Fig. 4e: green); Fig. 4h: gold Variant 7 1 Tree-rings 1-6 1761-1996 0.84 0.48 6.18 1053-1996 None (PLSR; Fig. 4, blue) h:orange Variant 8 4 Tree-rings and lake 1-7 1761-1996 0.76 0.66 6.91 1053-1996 1-10 (Fig. 4a, blue)/11-31 (Fig. 4b, blue)/31-51 (Fig. 4c, black; all OLSR) and >51 (PLSR, Fig. 4f, black); Fig. 4h: blue Variant 9 4 Tree-rings and lake 1-8 1776-1949 0.76 0.66 7.16 1173-1949 1-10 (Fig. 4a, blue)/11-31 (Fig. 4b, black)/31-51 ((Fig. 4c, blue; all OLSR) and >51 (PLSR, (Fig. 4f, black); Fig. 4h: coral NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Trachsel, M. Investigator : Kamenik, C. Investigator : Grosjean, M. Investigator : McCarroll, D. Investigator : Moberg, A. Investigator : Brázdil, R. Investigator : Büntgen, U. Investigator : Dobrovolný, P. Investigator : Esper, J. Investigator : Frank, D.C. Investigator : Friedrich, M. Investigator : Glaser, R. Investigator : Larocque-Tobler, I. Investigator : Nicolussi, K. Investigator : Riemann, D. 2012-06-13 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/12996 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/trachsel2012/trachsel2012temperature.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/trachsel2012/trachsel2012temperature.xls https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/trachsel2012/trachsel2012temperature.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/trachsel2012/trachsel2012temperature.xls English https://www.ncdc.noaa.gov/paleo/study/12996 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/trachsel2012/trachsel2012temperature.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/trachsel2012/trachsel2012temperature.xls Trachsel, M., C. Kamenik, M. Grosjean, D. McCarroll, A. Moberg, R. Brázdil, U. Büntgen, P. Dobrovolný, J. Esper, D.C. Frank, M. Friedrich, R. Glaser, I. Larocque-Tobler, K. Nicolussi, and D. Riemann. 2012. Multi-archive summer temperature reconstruction for the European Alps, AD 1053-1996. Quaternary Science Reviews, Vol. 46, pp. 66-79. doi:10.1016/j.quascirev.2012.04.021 START YEAR: 1053 AD * END YEAR: 1996 AD 4 43 19 49