El Nino seems to be reappearing

Forecasting weather for me can often be as error-prone as forecasting the market. Nevertheless I wish to show here some rather unsettling graphs.

The first is the El Nino Southern Oscillation Index:
This graph (courtesy of the Australian Bureau of Meteorology) is one tool used to predict and determine El-Nino or La-Nina conditions. Any result above 5 indicates La Nina favourable conditions and any result under 0 indicates favourable El Nino conditions. The number used in the index is the difference in Air Pressure between Tahiti and Darwin. A positive number means that the air pressure in Tahiti is greater, while a negative number means that the air pressure in Darwin is greater. Lower air pressure is associated with more rainfall. The fact that the index has moved into negative territory means that Air pressure in Tahiti is dropping below that of Darwin. This means that there is less likelihood of rain in South-Eastern Australia, which matches an El-Nino event.

But the ENSO graph above is not the only one to look at. Here's another important one:
This graph shows temperature throughout the equatorial region of the Pacific Ocean. You can see Papua New Guinea there in the West. If the graph went East more you would see Peru. What is important is the bottom graph which shows temperature anomalies. As you can see, the temperature of seawater in the Eastern Pacific near South America is heating up above normal. Warm seawater is more likely to produce rain while cool seawater is not.

Let me just put this simply, the conditions that we see here are typical of a developing El Nino weather pattern. This means more dry weather for South Eastern Australia, which will probably turn into the worst drought in Australia's history. Not good.

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