As Happ notes, “The gorilla in the climate change closet is ENSO. Until the mechanism responsible for the fluctuation in tropical temperatures that feeds into global temperatures is described and the resulting contribution to global temperature is quantified we have no hope of quantifying the temperature change that is due to ‘anthropogenic’
Global warming advocates made much of the warm temperatures and lack of snow for parts of the recent Winter Olympics in Vancouver. Skeptics pointed to the cold and snow on the east side of the continent. The pattern was created by the waves in the Polar Front separating cold polar air from warm tropical air pushing north on the west side and south on the east side.
El Nino in the Pacific enhanced the situation. Everything about the winter was normal but that is not what alarmists claim.
Historical El Nino
Many incorrectly think El Nino is a new phenomenon resulting from global warming. Scientific awareness and its influence on global climate are new, but people who sailed the Pacific like the Inca knew it well. Spanish sailors knew and named it after the little Christ child because it occurred near Christmas. The opposite pattern, La Nina, means a little girl.
Inca priests went high in the Andes in the spring to study the Pleiades star formation. They used the difference between a clear or shimmering cluster for a rainfall prediction and when to plant potatoes. Atmospheric conditions vary between unstable and stable conditions as the Pacific Ocean switches between El Nino and La Nina. These determine the precipitation pattern Quinn and Neal produced a detailed record of El Nino events from 1522 to 1987 in a publication ironically edited by Raymond Bradley and Phil Jones of CRU notoriety.
Sir Francis Drake was a first class navigator but needed someone who knew the Pacific currents when he rounded Cape Horn in 1579. He captured a Spanish vessel and used the navigator de Moreno to avoid the El Nino currents and reach the west coast of Canada. De Moreno became ill near Oregon and was put ashore to increase his chances of survival. He promptly walked to Mexico and reported his story to Spanish authorities.
Science of El Nino
Early in the 20th century Sir Gilbert Walker produced the first scientific discussions of alternating wind patterns in the Pacific subsequently named the Walker Circulation.
In 1924 he introduced the term Southern Oscillation (SO), which is now used as an Index (SOI) to measure the difference in pressure between Darwin in Australia and Tahiti.
Figure 2 is a schematic of El Nino and La Nina showing the reversal of surface ocean currents that creates alternating warm and cold water on each side of the Pacific. Precipitation patterns are also affected and countries like Australia use ENSO to try and make accurate weather forecasts.
They are forecasting a decline in the current El Nino. Others are not so sure, which underlines the problems with understanding the mechanisms. Read more.