@article{9d90ece912764fb19a11f3e5e304c5ab,
title = "The role of historical forcings in simulating the observed Atlantic multidecadal oscillation",
abstract = "We analyze the Atlantic multidecadal oscillation (AMO) in the preindustrial (PI) and historical (HIST) simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to assess the drivers of the observed AMO from 1865 to 2005. We draw 141 year samples from the 41 CMIP5 model's PI runs and compare the correlation and variance between the observed AMO and the simulated PI and HIST AMO. The correlation coefficients in 38 forced (HIST) models are above the 90% confidence level and explain up to 56% of the observed variance. The probability that any of the unforced (PI) models do as well is less than 3% in 31 models. Multidecadal variability is larger in 39 CMIP5 HIST simulations and in all HIST members of the Community Earth System Model Large Ensemble than their corresponding PI. We conclude that there is an essential role for external forcing in driving the observed AMO.",
keywords = "Atlantic multidecadal oscillation, CESM-LE, CMIP5",
author = "Murphy, {Lisa N.} and Katinka Bellomo and Mark Cane and Amy Clement",
note = "Funding Information: This research was supported by National Science Foundation grant NSF-1304540 to A.C. Clement and L.N. Murphy. We acknowledge the World Climate Research Program's Working Group on Coupled Modeling, which is responsible for CMIP, and we thank the climate modeling groups (listed in Table of this paper) for producing and making available their model output. For CMIP the U.S. Department of Energy's Program for Climate Model Diagnosis and Intercomparison provides coordinating support and led development of software infrastructure in partnership with the Global Organization for Earth System Science Portals. We also acknowledge the CESM Large Ensemble Community Project and supercomputing resources provided by NSF/CISL/Yellowstone. NOAA ERSSTv4 data and COBE SST data were provided by the NOAA/OAR/ESRL PSD, Boulder, Colorado, USA, from their web site at http://www.esrl.noaa.gov/psd/. We are grateful to Y. Kushnir and M-F. Ting for comments on an earlier draft of this manuscript and two anonymous reviewers who helped improve our manuscript.",
year = "2017",
month = mar,
day = "16",
doi = "10.1002/2016GL071337",
language = "English (US)",
volume = "44",
pages = "2472--2480",
journal = "Geophysical Research Letters",
issn = "0094-8276",
publisher = "American Geophysical Union",
number = "5",
}