Raghu Murtugudde

University of Maryland
El Nino-Southern Oscillation is the most dominant mode of climate variability at interannual time-scales and has been a focus of research for many decades and prediction efforts for the last couple of decades. Despite the vast number of papers on all aspects of ENSO, ENSO variability, and ENSO diversity, and ENSO predictions and predictabilty, no model has an established record of consistently successful ENSO prediction. The 2012 Seasonal-to-interannual predictions offered another reminder of the severe limitations of the state-of-the art climate prediction models. The recharge-discharge oscillator remains the most robust paradigm for ENSO and it is clearly known by now that while every ENSO may offer a different surface expression, not much attention is paid to what if anything may remain commonto all events before the different flavors of surface expressions emerge. Teleconnections do differ based on the surface expressions or sea surface temperature anomalies and teleconnections tend to be the focus of most prediction efforts. Any real progress on reliable ENSO predictions may only be possible if the exact timing and cause of the onset is understood fully along with whether that process is common to all ENSOs. A hypothesis is offered for the onset and the discussion will explore if the process is common to all flavors of ENSO.