High-resolution marine data and transient simulations support orbital forcing of ENSO amplitude since the mid-Holocene
نویسندگان
چکیده
Lack of constraint on spatial and long-term temporal variability the El Niño southern Oscillation (ENSO) its sensitivity to external forcing limit our ability evaluate climate models ENSO future projections. Current knowledge Holocene derived from paleoclimate reconstructions does not separate role insolation internal variability. Using an updated synthesis coral bivalve monthly resolved records, we build composite records seasonality interannual in four regions tropical Pacific: Eastern Pacific (EP), Central (CP), Western (WP) South West (SWP). An analysis uncertainties due sampling chaotic multidecadal centennial by short allows for objective comparison with transient simulations (mid-Holocene present) performed using different Earth System models. Sea surface temperature pseudo-δ18O are used model-data comparisons assess potential influence hydroclimate change records. We confirm significance minimum (HEM) 3-6ka compared low frequency unforced modulation ENSO, a reduction variance ∼50 % EP ∼80 CP. The approach suggests that increasing trend since 6ka can be attributed insolation, while underestimate orbital factor 4.7 data, even when accounting large Precession-induced seasonal range is positively linked lesser extent other regions, both observations. Our regional yields insights into past expression across Pacific. In SWP, today under Convergence Zone (SPCZ), was increased ∼200 during HEM, indicating SPCZ independent millennial time scales.
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ژورنال
عنوان ژورنال: Quaternary Science Reviews
سال: 2021
ISSN: ['1873-457X', '0277-3791']
DOI: https://doi.org/10.1016/j.quascirev.2021.107125