700 Year El Niño/Southern Oscillation (ENSO) Niño3.4 Index Reconstruction Li, J.; Xie, S.-P.; Cook, E.R.; Morales, M.; Christie, D.A.; Johnson, N.C.; Chen, F.-H.; D'Arrigo, R.D.; Fowler, A.M.; Gou, X.; Fang, K. Li, J. Xie, S.-P. Cook, E.R. Morales, M. Christie, D.A. Johnson, N.C. Chen, F.-H. D'Arrigo, R.D. Fowler, A.M. Gou, X. Fang, K. Atmospheric and Oceanic Circulation Patterns Reconstruction ENSO earth science/paleoclimate/climate reconstructions|tree ring (age,null,null,year Common Era,null,climate reconstructions|tree ring,null,null,N,null) earth science/paleoclimate/climate reconstructions|tree ring (sea surface temperature,ring width,null,degree Celsius,Nov-Jan,climate reconstructions|tree ring,anomalized,principal component analysis|regression analysis,N,reference period: 1971-2000 A.D.; calibration data set: Kaplan et al. 1998; principal components regression) earth science/paleoclimate/reconstructions (Nino3.4>LATITUDE >LONGITUDE ) The El Niño/Southern Oscillation (ENSO) is the dominant mode of interannual climate variability on Earth, alternating between anomalously warm (El Niño) and cold (La Niña) conditions in the tropical Pacific at intervals of 2-8 years. The amplitude of ENSO variability affects the occurrence and predictability of climate extremes around the world, but our ability to detect and predict changes in ENSO amplitude is limited by the fact that the instrumental record is too short to characterize its natural variability. Here we use the North American Drought Atlas - a database of drought reconstructions based on tree-ring records - to produce a continuous, annually resolved record of ENSO variability over the past 1,100 years. Our record is in broad agreement with independent, ENSO-sensitive proxy records in the Pacific and surrounding regions. Together, these records indicate that ENSO amplitude exhibits a quasi-regular cycle of 50-90 years that is closely coupled to the tropical Pacific mean state. Anomalously warm conditions in the eastern Pacific are associated with enhanced ENSO variability, consistent with model simulations. The quasi-periodic ENSO amplitude modulation reported here offers a key observational constraint for improving models and their prediction of ENSO behaviour linked to global warming. STUDY NOTES: An index of canonical El Niño/Southern Oscillation (ENSO) variability for the past seven centuries, derived from 2,222 tree-ring chronologies from Asia, New Zealand, and North and South America. The reconstruction targets the prior winter (November-January, NDJ) Niño3.4 index, and covers 1301-2005. SST anomalies (SSTAs) are relative to the mean of observed SSTs during 1971-2000. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Li, J. Investigator : Xie, S.-P. Investigator : Cook, E.R. Investigator : Morales, M. Investigator : Christie, D.A. Investigator : Johnson, N.C. Investigator : Chen, F.-H. Investigator : D'Arrigo, R.D. Investigator : Fowler, A.M. Investigator : Gou, X. Investigator : Fang, K. 2013-07-03 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/14632 https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/enso-li2013.txt https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/enso-li2013.txt English https://www.ncdc.noaa.gov/paleo/study/14632 https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/enso-li2013.txt Jinbao Li, Shang-Ping Xie, Edward R. Cook, Mariano S. Morales, Duncan A. Christie, Nathaniel C. Johnson, Fahu Chen, Rosanne D'Arrigo, Anthony M. Fowler, Xiaohua Gou, and Keyan Fang. 2013. El Niño modulations over the past seven centuries. Nature Climate Change, DOI: 10.1038/nclimate1936. Published online 02 July 2013 Li, J., S.-P. Xie, E.R. Cook, G. Huang, R. D'Arrigo, F. Liu, J. Ma, and X.-T. Zheng. 2011. Interdecadal modulation of El Niño amplitude during the past millennium. Nature Climate Change, Vol. 1, Issue 2, pp. 114-118, May 2011 doi:10.1038/nclimate1086 START YEAR: 1301 AD * END YEAR: 2005 AD -170 -5 -120 5