The El Niño–Southern Oscillation (ENSO) shapes global climate patterns yet its sensitivity to external climate forcing remains uncertain. Modeling studies suggest that ENSO is sensitive to sulfate aerosol forcing associated with explosive volcanism but observational support for this effect remains ambiguous. Here, we used absolutely dated fossil corals from the central tropical Pacific to gauge ENSO’s response to large volcanic eruptions of the last millennium. Superposed epoch analysis reveals a weak tendency for an El Niño–like response in the year after an eruption, but this response is not statistically significant, nor does it appear after the outsized 1257 Samalas eruption. Our results suggest that those models showing a strong ENSO response to volcanic forcing may overestimate the size of the forced response relative to natural ENSO variability.
Bibliographical noteFunding Information:
This research was supported by the Peter Voss Postdoctoral Fellowship in the Institute at Brown for Environment and Society, Brown University, as well as the University of Texas at Austin, Institute for Geophysics Postdoctoral Fellowship, both awarded to S.D.; by NSF Marine Geology and Geophysics awards 0752091, 1502832, and 1836645 to K.C.; NSF OCE award 0752585 to C.D.C. and K.C.; and NOAA grant NA18OAR4310426 to J.E.G.