El Nino and La Nino and water levels for the berg

Hi Guys

Here is an interesting link to El Nino and La Nino phenomena, and shows the relative intensities of the two. ggweather.com/enso/oni.htm
I am looking for those in the know if they can give me an educated idea what the next 5 to 10 years would look like in the berg and South Africa as a result of these phenomena.

Thanks
K

Link?

The state of the Pacific is predictable 3 to 6 months ahead based on the propagation of Kelvin waves along the thermocline in the Pacific. Good places to find out about these forecasts are IRI ENSO advisory.
iri.columbia.edu/our-expertise/climate/forecasts/enso/current/

The system has little to no predictability beyond 12 months.

However there is a tendency for the Pacific to undergo quasi decadal variability where there is a run of La Niña events over about 10 years and then a run of El Niño events. This is called the Pacific Decadal Oscillation. The mechanisms behind it are not well understood unlike those for La Niña and El Niño.
The PDO seems to be switching to a phase of El Niño events. This would bias summers in SA to be hotter and drier but there is little confidence in such statements because we don't properly understand the mechanism behind the PDO.

Further to tiska's observations, ENSO appears to be entering a weak La Niña which could mean above average rainfall for the summer rainfall areas. For more info on SA Weather Services 'predictions' for this summer, go to WaterWise/SAWS

At a desktop now rather than my phone - so I will elaborate a bit on the PDO
"However there is a tendency for the Pacific to undergo quasi decadal variability where there is a run of La Niña events over about 10 years and then a run of El Niño events."
More accurately, when the PDO is in a phase that favours El Nino, there are strong El Nino events but La Nina events that occur tend to be weak. When the PDO is in a phase that favours La Nina, there are strong La Nina events but the El Nino events that do occur tend to be weak. It is likely that we have recently completed a phase of stronger La Ninas (with weak El Nino events from time to time) which leads to wetter conditions over SA and entered a phase of stronger El Ninos (with weaker La Ninas) which means a switch to hotter, drier summers. This last El Nino was a strong one and marked the possible switch in PDO phase. The El Nino features a lot of heat released from the ocean into the atmosphere and leads to a globally averaged warm year. A lot of records of high temperatures across the planet have been broken over the last 18 months as a result of this. During the other PDO phase, with stronger La Nina events, heat is taken up by the oceans. The global temperatures did not increase much during the most recent PDO phase featuring the strong La Ninas (and weak El Ninos).

A single La Nina event normally lasts 18-24 months. A single El Nino event normally lasts about 18-24 months. Both El Nino and La Nina events peak around December. Whether an El Nino or La Nina event is developing is most difficult to predict in the Boreal Spring (April/May). This is known as the Spring Predictability Barrier.

Thanx for the info so far. Here is that lil that i forgot to add. ggweather.com/enso/oni.htm



The attached graph of events from that site makes it quite clear. I recall the 82/83 water restrictions we had in durbs, and the 84 cyclone demoina that followed. Are cyclones part of the cycle, or just localised events, the graph shows a weak la nina, so just wondered?

The graph also shows that after a very strong el nino event, it seems to get a little easier for a few years. ito intensity. The trough between peaks has been the longest between 97/98 and 2015/16. The 2016 spike certainly seemed to be a really strong one, which could indicate that they will weaken for the next 6-10 years give or take. It also seems to show that there could be a strong wet season this coming December and on into 2017.

Or is this to a simplistic understanding of the system?