What we see in these two slides is that when we have a warm north Atlantic and a cool eastern tropical Pacific we have the recent drought that we have experienced in the western United States
When we have opposite conditions in other words, cool North Atlantic sea surface temperatures and a warm eastern tropical pacific we have wet conditions in the in North America.
Like these children’s jump ropes, each of the three cycles – El Nino, the Pacific Decadal Oscillation and the Atlantic Multi-decadal Oscillation – fluctuate at different rates.