RQL's Blog 菜鸟成长记

The History of ENSO Studies


In fact, this is my presonal presentation in English class, which I think is important.

Recently, I am reading the book——Climate Change and Climate Modeling. A chapter of this book introduces the history of ENSO studies which I think is interesting.

As we all know, ENSO is a climate phenomenon which includes the oceanic and atmospheric part. It can affect global climate, leading to harsh winter, drought, flood and hurricanes. Due to the great importance of ENSO, I think most people here have to consider its influence in your research. Learn the history of its studies may be useful for you to fully understand it.

Long before climate scientists started to study ENSO, Peruvian fishermen knew how to read it in the water due to its influence on fisheries and other coastal phenomena. They named the warming that appears after Christmas in certain years as “El Niño” which means the child of Christ.

In 1923, Gilbert Walker published negative correlation of pressure in western and eastern Pacific Ocean when he was working in India on monsoon predictors. He later shows that this irregular oscillation is associated with changes in rainfall and winds. He names it the Southern Oscillation.

These pieces were developed independently until the 1969, when Jacob Bjerknes put them together and found: The Southern Oscillation and El Nino could be understood as two faces of the same phenomenon, soon known as the El Nino Southern Oscillation (ENSO). And he proposed the Bjerknes hypothesis to explain the development of EI Nino from the point of ocean-atmosphere interaction.

Not long after Bjerknes’ work, this guy notices that an increase in sea level height in the western Pacific tends to precede El Niño and notes the potential role of oceanic dynamics in communicating this to the eastern pacific.

After that, Oceanographers and atmospheric scientists gradually became aware that tropical regions have interesting dynamics that is very different from the typical midlatitude behavior that had been studied in traditional oceanography and meteorology, which led to the development in tropical oceanography and modeling.

However, in 1982–83, the second biggest EI Nino of the century catches experts unawares. This EI Nino event led to widespread flooding across the southern United States, droughts in Indonesia and Australia. The estimated economic impact was over US$8 billion.

As a result of this, the Tropical Ocean–Global Atmosphere program is launched during 1985-1995 which established an advanced ocean observing system to support research and forecasting of ENSO cycles.

Then, the ENSO theory and model are developed rapidly.

In 1997-98, when scientists successfully predict the biggest EI Nino of the century, El Niño becomes a household word.

上一篇 ITCZ review