In the absence of a strong ENSO event, global circulation patterns may be driven by the stirring of other spoons. At the moment, neither El Ni o nor La Ni a is happening. Conditions are pretty much normal. In other words, with no El Nino to stir the glass this season, predictions of what this winter will bring are dicey. ENSO is a cyclical change in surface-water temperatures of the Pacific Ocean near the equator.
Convection is the process in which air close to the surface is warmed and then rises.
As air rises from one region, air from surrounding areas is drawn in. The altering pattern of how this occurs over the Pacific with the occurrence of an ENSO event changes the way air circulates across the globe. When conditions are normal in the Pacific Ocean near the equator, strong winds push water to the west. An El Ni o begins when the winds blowing to the west slacken, Glantz said. The accumulated water in the west sloshes across the Pacific, dramatically warming the surface waters to the east.