A Robust Null Hypothesis for the Potential Causes of Megadrought in Western North America

被引:50
作者
Ault, Toby R. [1 ]
George, Scott St. [2 ]
Smerdon, Jason E. [3 ]
Coats, Sloan [4 ]
Mankin, Justin S. [3 ,5 ,6 ]
Carrillo, Carlos M.
Cook, Benjamin I. [3 ,5 ]
Stevenson, Samantha [7 ]
机构
[1] Cornell Univ, Dept Earth & Atmospher Sci, Ithaca, NY 14850 USA
[2] Univ Minnesota, Dept Geog, Minneapolis, MN 55455 USA
[3] Columbia Univ, Lamont Doherty Earth Observ, Div Ocean & Climate Phys, Palisades, NY USA
[4] Natl Ctr Atmospher Res, Climate & Large Scale Dynam Lab, POB 3000, Boulder, CO 80307 USA
[5] NASA, Goddard Inst Space Studies, New York, NY 10025 USA
[6] Dartmouth Coll, Dept Geog, Hanover, NH 03755 USA
[7] Univ Calif Santa Barbara, Bren Sch Environm Sci & Management, Santa Barbara, CA 93106 USA
基金
美国国家科学基金会;
关键词
EL-NINO; EQUATORIAL PACIFIC; ICE-AGE; CLIMATE; DROUGHT; VARIABILITY; TELECONNECTIONS; RECONSTRUCTIONS; OSCILLATION; EVOLUTION;
D O I
10.1175/JCLI-D-17-0154.1
中图分类号
P4 [大气科学(气象学)];
学科分类号
0706 ; 070601 ;
摘要
The western United States was affected by several megadroughts during the last 1200 years, most prominently during the Medieval Climate Anomaly (MCA; 800 to 1300 CE). A null hypothesis is developed to test the possibility that, given a sufficiently long period of time, these events are inevitable and occur purely as a consequence of internal climate variability. The null distribution of this hypothesis is populated by a linear inverse model (LIM) constructed from global sea surface temperature anomalies and self-calibrated Palmer drought severity index data for North America. Despite being trained only on seasonal data from the late twentieth century, the LIM produces megadroughts that are comparable in their duration, spatial scale, and magnitude to the most severe events of the last 12 centuries. The null hypothesis therefore cannot be rejected with much confidence when considering these features of megadrought, meaning that similar events are possible today, even without any changes to boundary conditions. In contrast, the observed clustering of megadroughts in the MCA, as well as the change in mean hydroclimate between the MCA and the 1500-2000 period, are more likely to have been caused by either external forcing or by internal climate variability not well sampled during the latter half of the twentieth century. Finally, the results demonstrate that the LIM is a viable tool for determining whether paleoclimate reconstructions events should be ascribed to external forcings or to "out of sample'' climate mechanisms, or if they are consistent with the variability observed during the recent period.
引用
收藏
页码:3 / 24
页数:22
相关论文
共 85 条
[41]   Support for global climate reorganization during the "Medieval Climate Anomaly" [J].
Graham, N. E. ;
Ammann, C. M. ;
Fleitmann, D. ;
Cobb, K. M. ;
Luterbacher, J. .
CLIMATE DYNAMICS, 2011, 37 (5-6) :1217-1245
[42]  
Graham NE, 2007, CLIMATIC CHANGE, V83, P241, DOI 10.1007/s 10584-007-9239-2
[43]   UNDERSTANDING EL NINO IN OCEAN-ATMOSPHERE GENERAL CIRCULATION MODELS Progress and Challenges [J].
Guilyardi, Eric ;
Wittenberg, Andrew ;
Fedorov, Alexey ;
Collins, Mat ;
Wang, Chunzai ;
Capotondi, Antonietta ;
van Oldenborgh, Geert Jan ;
Stockdale, Tim .
BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY, 2009, 90 (03) :325-+
[44]   POSSIBLE ROLE OF CLIMATE IN THE COLLAPSE OF CLASSIC MAYA CIVILIZATION [J].
HODELL, DA ;
CURTIS, JH ;
BRENNER, M .
NATURE, 1995, 375 (6530) :391-394
[45]   The Medieval Warm Period, the Little Ice Age and simulated climatic variability [J].
Hunt, B. G. .
CLIMATE DYNAMICS, 2006, 27 (7-8) :677-694
[46]   Reduced space optimal analysis for historical data sets: 136 years of Atlantic sea surface temperatures [J].
Kaplan, A ;
Kushnir, Y ;
Cane, MA ;
Blumenthal, MB .
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 1997, 102 (C13) :27835-27860
[47]   THE COMMUNITY EARTH SYSTEM MODEL (CESM) LARGE ENSEMBLE PROJECT A Community Resource for Studying Climate Change in the Presence of Internal Climate Variability [J].
Kay, J. E. ;
Deser, C. ;
Phillips, A. ;
Mai, A. ;
Hannay, C. ;
Strand, G. ;
Arblaster, J. M. ;
Bates, S. C. ;
Danabasoglu, G. ;
Edwards, J. ;
Holland, M. ;
Kushner, P. ;
Lamarque, J. -F. ;
Lawrence, D. ;
Lindsay, K. ;
Middleton, A. ;
Munoz, E. ;
Neale, R. ;
Oleson, K. ;
Polvani, L. ;
Vertenstein, M. .
BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY, 2015, 96 (08) :1333-1349
[48]   Climate change in the Fertile Crescent and implications of the recent Syrian drought [J].
Kelley, Colin P. ;
Mohtadi, Shahrzad ;
Cane, Mark A. ;
Seager, Richard ;
Kushnir, Yochanan .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2015, 112 (11) :3241-3246
[49]   Evolution of the sun's spectral irradiance since the Maunder Minimum [J].
Lean, J .
GEOPHYSICAL RESEARCH LETTERS, 2000, 27 (16) :2425-2428
[50]   Global Signatures and Dynamical Origins of the Little Ice Age and Medieval Climate Anomaly [J].
Mann, Michael E. ;
Zhang, Zhihua ;
Rutherford, Scott ;
Bradley, Raymond S. ;
Hughes, Malcolm K. ;
Shindell, Drew ;
Ammann, Caspar ;
Faluvegi, Greg ;
Ni, Fenbiao .
SCIENCE, 2009, 326 (5957) :1256-1260