The term “dipole” implies a seesaw, inverse variations of an element at the extremities of an oscillation system. The Southern Oscillation and North Atlantic Oscillation are examples of such mainly standing oscillations in pressure. By contrast, for the sea surface temperature (SST) fields in the tropical Atlantic and equatorial Indian Oceans, the SST gradient was found to be closely associated with climatic anomalies, but there is no seesaw. Use the term dipole is misleading.
University of Wisconsin—Madison, Madison, Wisconsin