Collaborative Research: P2C2--The Role of El Niño/Southern Oscillation (ENSO) Nonlinearities and Asymmetries in Modulating Tropical Pacific Climate

University Of Illinois At Urbana-Champaign, Urbana IL

Investigators

Abstract

This collaborative project generally aims to develop a multi-scale model-proxy synthesis to explore the relationship between multi-decadal ENSO variability and tropical Pacific seas surface temperature (SST) gradients in past climates and help assess model skill in simulating these relationships in past, present, and potential future climates. The activity of El Niño/Southern Oscillation (ENSO) varies significantly at multi-decadal to centennial timescales, even in the absence of external forcing. Periods of increased ENSO activity may affect the mean state of the tropical Pacific, via a decrease of the zonal SST gradient due to residual heating from large El Niño events. In turn, ENSO-modulated multi-decadal variations of the zonal SST gradient can exert influence on global temperature trends. These causal links are argued to be poorly constrained in models and observations, at present. The merit of the project is high because it identifies an interesting scientific issue (i.e., the ENSO-mean state interaction) that is important for advancing our understanding the dynamics of ENSO and decadal climate variability that can benefit from using paleo-climate proxies. The anticipated results have the potential to aid in interpreting the decadal variability observed in the present-day climate and the selection of climate models that have the potential to make more accurate projections of future climate. The Broader Impacts involve the potential for creating increased confidence in theory and models of future climate in the tropics; helping create a new generation of earth scientists willing to bridge the divide between the worlds of modeling and paleoclimate data; support two early career female scientists; and support two doctoral students.