Abstract
AbstractEl Niño-Southern Oscillation (ENSO) sea surface temperature (SST) anomaly skewness encapsulates the nonlinear processes of strong ENSO events and affects future climate projections. Yet, its response to CO2 forcing remains not well understood. Here, we find ENSO skewness hysteresis in a large ensemble CO2 removal simulation. The positive SST skewness in the central-to-eastern tropical Pacific gradually weakens (most pronounced near the dateline) in response to increasing CO2, but weakens even further once CO2 is ramped down. Further analyses reveal that hysteresis of the Intertropical Convergence Zone migration leads to more active and farther eastward-located strong eastern Pacific El Niño events, thus decreasing central Pacific ENSO skewness by reducing the amplitude of the central Pacific positive SST anomalies and increasing the scaling effect of the eastern Pacific skewness denominator, i.e., ENSO intensity, respectively. The reduction of eastern Pacific El Niño maximum intensity, which is constrained by the SST zonal gradient of the projected background El Niño-like warming pattern, also contributes to a reduction of eastern Pacific SST skewness around the CO2 peak phase. This study highlights the divergent responses of different strong El Niño regimes in response to climate change.
Publisher
Springer Science and Business Media LLC
Subject
Atmospheric Science,Environmental Chemistry,Global and Planetary Change
Reference71 articles.
1. McPhaden, M. J., Zebiak, S. E. & Glantz, M. H. ENSO as an integrating concept in earth science. Science (1979) 314, 1740–1745 (2006).
2. Neelin, J. D. et al. ENSO theory. J. Geophys Res Oceans 103, 14261–14290 (1998).
3. Taschetto, A. S. et al. El Niño Southern Oscillation In A Changing Climate 1st edn, 309–335 (American Geophysical Union, 2020).
4. An, S.-I. A review of interdecadal changes in the nonlinearity of the El Niño-Southern Oscillation. Theor. Appl. Climatol. 97, 29–40 (2009).
5. Cai, W., van Rensch, P., Cowan, T. & Sullivan, A. Asymmetry in ENSO teleconnection with regional rainfall, its multidecadal variability, and impact. J. Clim. 23, 4944–4955 (2010).
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