Detecting the Emergence of Wintertime ENSO Teleconnection Changes in the GFDL SPEAR Large Ensemble

Abstract:

The impacts of the El Niño-Southern Oscillation (ENSO) are expected to change under increasing greenhouse gas concentrations, but the large internal variability of ENSO and its teleconnections makes it challenging to detect such changes in a single realization of nature. In this study, we explore both the internal variability and radiatively forced changes of wintertime ENSO teleconnection patterns through the analysis of 30-member initial condition ensembles of the SPEAR global coupled GCM, recently developed by NOAA's Geophysical Fluid Dynamics Laboratory (GFDL). We focus on the projected changes of the large-scale circulation, temperature, and precipitation patterns associated with ENSO and the timing with which these changes are expected to emerge from the noise of internal climate variability. We also examine the connections between teleconnection changes and changes in mean state and in ENSO properties.