Northern Hemisphere 1,500 Year Regional MXD and TRW Tree-Ring Chronologies Stoffel, M.; Khodri, M.; Corona, C.; Guillet, S.; Poulain, V.; Bekki, S.; Guiot, J.; Luckman, B.H.; Oppenheimer, C.; Lebas, N.; Beniston, M.; Masson-Delmotte, V. Stoffel, M. Khodri, M. Corona, C. Guillet, S. Poulain, V. Bekki, S. Guiot, J. Luckman, B.H. Oppenheimer, C. Lebas, N. Beniston, M. Masson-Delmotte, V. Air Temperature Reconstruction earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Calimani mountains) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,standard,N,French Alps; negative exponential fit) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,standard,N,Sarejmek; negative exponential fit) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Coastal Alaska) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Firth River) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Indigirka) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,standard,N,negative exponential fit) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Sartan River) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Seward Peninsula) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Swiss Alps) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Taymir) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Jamtland) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Thelon) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Yamal) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Aktash_Valley) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Lac Romanel) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Solongotyn Davaa) earth science/paleoclimate/tree ring (age,null,null,year Common Era,null,tree ring,null,null,N,null) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,standard,N,Ary Ongorbynf River; negative exponential fit) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Athabasca) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Churchill) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Tatra Mountains) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Vikran) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Pyrenees) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Labrador) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,NScan) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,standard,N,Polar Ural; negative exponential fit) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,STREC Quebec) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Tornetrask) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Zolotica) earth science/paleoclimate/reconstructions (Northern Hemisphere Extratropics>LATITUDE >LONGITUDE ) Explosive volcanism can alter global climate, and hence trigger economic, political and demographic change. The climatic impact of the largest volcanic events has been assessed in numerous modelling studies and tree-ring-based hemispheric temperature reconstructions. However, volcanic surface cooling derived from climate model simulations is systematically much stronger than the cooling seen in tree-ring-based proxies, suggesting that the proxies underestimate cooling; and/or the modelled forcing is unrealistically high. Here, we present summer temperature reconstructions for the Northern Hemisphere from tree-ring width and maximum latewood density over the past 1,500 years. We also simulate the climate effects of two large eruptions, in AD 1257 and 1815, using a climate model that accounts explicitly for self-limiting aerosol microphysical processes. Our tree-ring reconstructions show greater cooling than reconstructions with lower spatial coverage and based on tree-ring width alone, whereas our simulations show less cooling than previous simulations relying on poorly constrained eruption seasons and excluding nonlinear aerosol microphysics. Our tree-ring reconstructions and climate simulations are in agreement, with a mean Northern Hemisphere extra-tropical summer cooling over land of 0.8 to 1.3C for these eruptions. This reconciliation of proxy and model evidence paves the way to improved assessment of the role of both past and future volcanism in climate forcing. STUDY NOTES: The proxy records are maximum-latewood-density and tree-ring width chronologies grouped in 30 clusters and that portray a significant local summer temperature signal. The proxy composite is calibrated and validated against June-August temperature anomalies from the CRUTEM4v and BEST networks 40-90N. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Stoffel, M. Investigator : Khodri, M. Investigator : Corona, C. Investigator : Guillet, S. Investigator : Poulain, V. Investigator : Bekki, S. Investigator : Guiot, J. Investigator : Luckman, B.H. Investigator : Oppenheimer, C. Investigator : Lebas, N. Investigator : Beniston, M. Investigator : Masson-Delmotte, V. 2015-09-02 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/19039 https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/stoffel2015nhtemp.txt https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/stoffel2015nhtemp.txt English https://www.ncdc.noaa.gov/paleo/study/19039 https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/stoffel2015nhtemp.txt Markus Stoffel, Myriam Khodri, Christophe Corona, Sébastien Guillet, Virginie Poulain, Slimane Bekki, Joël Guiot, Brian H. Luckman, Clive Oppenheimer, Nicolas Lebas, Martin Beniston, Valérie Masson-Delmotte2015Estimates of volcanic-induced cooling in the Northern Hemisphere over the past 1,500 yearsNature Geoscience10.1038/ngeo2526http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2526.html START YEAR: 500 AD * END YEAR: 2012 AD -180 30 180 90