http://www.nature.com/nature/journal/vaop/ncurrent/full/nature14565.html
Timing and climate forcing of volcanic eruptions for the past 2,500 years M. Sigl, et al. Nature (2015) doi:10.1038/nature14565 08 July 2015 Abstract Volcanic eruptions contribute to climate variability, but quantifying these contributions has been limited by inconsistencies in the timing of atmospheric volcanic aerosol loading determined from ice cores and subsequent cooling from climate proxies such as tree rings. Here we resolve these inconsistencies and show that large eruptions in the tropics and high latitudes were primary drivers of interannual-to-decadal temperature variability in the Northern Hemisphere during the past 2,500 years. Our results are based on new records of atmospheric aerosol loading developed from high-resolution, multi-parameter measurements from an array of Greenland and Antarctic ice cores as well as distinctive age markers to constrain chronologies. 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Volcanoes of the World 3rd edn, (University of California Press, 2010) Download references Author information Abstract• References• Author information• Extended data figures and tables• Supplementary information Author footnotes Present address: Laboratory of Radiochemistry and Environmental Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland M. Sigl Affiliations Desert Research Institute, Nevada System of Higher Education, Reno, Nevada 89512, USA M. Sigl, J. R. McConnell, N. Chellman, O. J. Maselli & D. R. Pasteris Department of Earth and Space Sciences, University of Washington, Seattle, Washington 98195, USA M. Winstrup Space Sciences Laboratory, University of California, Berkeley, California 94720, USA K. C. Welten School of Geography, Archaeology and Palaeoecology, Queen's University Belfast, Belfast BT7 1NN, UK G. Plunkett & J. R. Pilcher Yale Climate and Energy Institute, and Department of History, Yale University, New Haven, Connecticut 06511, USA F. Ludlow Swiss Federal Research Institute WSL, 8903 Birmensdorf, Switzerland U. Büntgen Oeschger Centre for Climate Change Research, University of Bern, 3012 Bern, Switzerland U. Büntgen, H. Fischer & S. Schüpbach Global Change Research Centre AS CR, 60300 Brno, Czech Republic U. Büntgen Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA M. Caffee & T. E. Woodruff Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, Indiana 47907, USA M. Caffee Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark D. Dahl-Jensen, J. P. Steffensen & B. M. Vinther Climate and Environmental Physics, University of Bern, 3012 Bern, Switzerland H. Fischer & S. Schüpbach Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, 27570 Bremerhaven, Germany S. Kipfstuhl Department of History, The University of Nottingham, Nottingham NG7 2RD, UK C. Kostick Department of Geology, Quaternary Sciences, Lund University, 22362 Lund, Sweden F. Mekhaldi & R. Muscheler British Antarctic Survey, Natural Environment Research Council, Cambridge CB3 0ET, UK R. Mulvaney The Laboratory of Tree-Ring Research, University of Arizona, Tucson, Arizona 85721, USA M. Salzer Contributions M. Sigl designed the study with input from J.R.M., M.W., G.P., and F.L. The manuscript was written by M. Sigl, M.W., F.L., and J.R.M., with contributions from K.C.W., G.P., U.B., and B.M.V. in interpretation of the measurements. Ice-core chemistry measurements were performed by J.R.M., M. Sigl, O.J.M., N.C., D.R.P. (NEEM, B40, TUNU2013), and by S.S., H.F., R. Mulvaney (NEEM). K.C.W., T.E.W., and M.C. completed ice core 10Be measurements. F.M. and R. Muscheler were responsible for the NGRIP ice core 10Be measurements. M. Sigl, M.W., B.M.V., and J.R.M. analysed ice-core data and developed age models. F.L. and C.K. analysed historical documentary data. G.P. and J.R.P. performed ice-core tephra analysis and data interpretation. U.B. and M. Salzer contributed tree-ring data. D.D.-J., B.M.V., J.P.S., S.K., and O.J.M. were involved in drilling of the NEEM ice core. TUNU2013 was drilled by M. Sigl, N.C. and O.J.M., and the B40 ice core was drilled by S.K. and made available for chemistry measurements. D.D.-J. and J.P.S. were responsible for NEEM project management, sample distribution, logistics support, and management. All authors contributed towards improving the final manuscript. Competing financial interests The authors declare no competing financial interests. Corresponding author Correspondence to: J. R. McConnell Extended data figures and tables Abstract• References• Author information• Extended data figures and tables• Supplementary information Extended Data Figures Extended Data Figure 1: Location of study sites. (414 KB) a, Map showing locations (blue circles) of the five ice cores (WDC, B40, NEEM, NGRIP and TUNU) used in this study. Sites of temperature-limited tree-ring chronologies (green)42, 43, 76, 77, 78 and sites with annual Δ14C measurements from tree-rings in the eighth century CE (red outline) are marked. b, Metadata for the ice cores, tree-ring width (RW), maximum latewood density (MXD) chronologies and temperature reconstructions used3, 12, 16, 17, 25, 35, 42, 43, 76, 77, 78, 82. m water equ. a−1, metres of water equivalent per year. Extended Data Figure 2: Volcanic dust veils from historical documentary sources in relation to NEEM. (127 KB) Time series of 32 independently selected chronological validation points from well dated historical observations of atmospheric phenomena with known association to explosive volcanism (for example, diminished sunlight, discoloured solar disk, solar corona or Bishop's Ring, red volcanic sunset) as reported in the Near East, Mediterranean region, and China, before our earliest chronological age marker at 536 CE. Black lines represent the magnitude (scale on y axes) of annual sulfate deposition measured in NEEM (NEEM and NEEM-2011-S1 ice cores) from explosive volcanic events on the new NS1-2011 timescale. Red crosses depict the 24 (75%) historical validation points for which NEEM volcanic events occur within a conservative ±3-year uncertainty margin. Blue crosses represent the eight points for which volcanic events are not observed. The association between validation points and volcanic events is statistically significantly non-random at>99.9% confidence (P < 0.001). ppb, parts per billion. Extended Data Figure 3: Timescale comparison. (412 KB) Age differences of the timescales NS1-2011 and GICC05 for the NEEM-2011-S1/NEEM ice cores (a) and WD2014 and WDC06A-7 for WDC (b). Differences before 86 CE (the age of the ice that is now at the bottom of the ice core NEEM-2011-S1) deriving from the annual-layer counting of the NEEM core are shown for major volcanic eruptions relative to the respective signals in NGRIP on the annual-layer counted GICC05 timescale. Marker events used for constraining the annual-layer dating (solid line) and for chronology evaluation (dashed lines) are indicated. Triangles mark volcanic signals. Also indicated is the difference between WD2014 and the Antarctic ice-core chronology (AICC2012)92, based on volcanic synchronization between the WDC and EDC96 ice cores. Extended Data Figure 4: Post-volcanic suppression of tree growth. (329 KB) Superposed epoch analysis for large volcanic eruptions using the 28 largest volcanic eruptions (a); the 23 largest tropical eruptions (b); the five largest Northern Hemisphere eruptions (c); and eruptions larger than Tambora 1815 with respect to sulfate aerosol loading (d). Shown are growth anomalies of a multi-centennial tree-ring composite record (N-Tree) 15 years after the year of volcanic sulfate deposition, relative to the average of five years before the events. Dashed lines indicate 95% confidence intervals (2 s.e.m.) of the tree-ring growth anomalies associated with the multiple eruptions. Extended Data Figure 5: Major-element composition for ice core tephra QUB-1859 and reference material. (172 KB) Shown are selected geochemistry data: SiO2 versus total alkali (K2O + Na2O) (a); FeO (total iron oxides) versus TiO2 (b); SiO2 versus Al2O3 (c); and CaO versus MgO (d) from 11 shards extracted from the NEEM-2011-S1 ice core at 327.17–327.25 m depth, representing the age range 536.0–536.4 CE on the new, NS1-2011 timescale. Data for Late Holocene tephra from Mono Craters (California) are from the compilation by ref. 90; data for Aniakchak (Alaska) are from reference material published by ref. 88; and data for the early Holocene upper Finlay tephra, believed to be from the Edziza complex in the Upper Cordilleran Volcanic province (British Columbia), are from ref. 89. (See Supplementary Information for the Upper Finlay tephra.) Extended Data Tables Extended Data Table 1: Ice-core dating (169 KB) Extended Data Table 2: Annual-layer results using the StratiCounter program (157 KB) Extended Data Table 3: Historical documentary evidence for key volcanic eruption age markers 536-939 CE (144 KB) Extended Data Table 4: Large volcanic eruptions during the past 2,500 years (173 KB) Extended Data Table 5: Post-volcanic cooling (211 KB) PDF files Supplementary Information (80 KB) This file contains a Supplementary File guide Supplementary Data 2 (1.3 MB) This file contains 3 Supplementary data tables – see guide for details. Excel files Supplementary Data 1 (21 KB) This file contains ice core meta data and 10Be results – see guide for details. Supplementary Data 3 (8.7 MB) This file contains data from Greenland ice cores– see guide for details. Supplementary Data 4 (6.6 MB) This file contains data from Antarctica ice cores– see guide for details. Supplementary Data 5 (46 KB) This file contains volcanic reconstruction data– see guide for details. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout.
