El Niño Southern Oscillation (ENSO) has a history. Scientists sought for generations to explain the weather phenomena they noted in conjunction with the droughts that impacted India, China, Brazil, parts of Africa, and southeast Asia.

Solar energy along the Equator influences global climate. However, tropical areas “do not accumulate heat evenly” (226). Ocean currents and winds store this solar energy in multiple spots along the Equator. In the Pacific, trade winds from the east move warm surface water westward. A “Warm Pool” therefore appears in conjunction with an atmospheric “heat engine” called the Indo-Australian Convergence Zone (IACZ). This formation moves energy into the atmosphere from the ocean waters in the form of condensation. It is, essentially, a “cloud factory” in the Western Pacific Ocean (226).

ENSO happens when the trade winds reverse or stop, allowing the cloud factory to move east. The “Southern Oscillation” appears as barometric pressure in eastern and central Pacific region falls while it rises in the opposite direction. The Pacific Ocean warms off the Ecuadorian and Peruvian coasts, as does the Indian Ocean. When ENSO is strong, the monsoons in India and southern Africa fail, and rainfall decreases in northern China and Brazil’s Nordeste.