El Niño Warning | Expert explains expected disruptions to weather patterns and impacts

Added: 2026-06-07

[00:00:00]United Nations weather agency has forecast a potentially strong El Nino event in the upcoming months warning it could drive up global temperatures and increase the risk of extreme weather conditions. El Nino is a periodic warming of the sea surface temperatures in the central and eastern Pacific Ocean typically lasting between 9 and 12 months according to the world meteorological organization. For more on this now and what this means what's possible in terms of the impact of it we speak to Dr. Herman van Niekerk who's a senior lecturer in the department of geology at the University of Johannesburg. Thank you so much for your time sir. We really do appreciate it doc to chat about a very important conversation here. I mean how significant is it that you even have the United Nations warning of a potentially strong El Nino event and what indicators are there specifically for scientists currently observing that suggest it could intensify in the coming months?

[00:01:04]>> Um yeah, good morning. Thank you for getting me in to talk about this and you know just to start off of course I'm a geologist and people will want to know why is a geologist talking about weather and it's it's interesting because first of all you know as geologist we are for also deal of course at looking at weather in the past by looking at rocks but in my specific case we are also geologist that work in Antarctica and for us looking at the weather is extremely important because you know our life might depend on the weather.

[00:01:38]So I just want to put that out there so that the meteorologist don't get really get upset with me.

[00:01:42]Yes, um you know these like you said these El Nino occurrences you know happen between two to every two to seven years and it is basically a disruption as you said of the sea surface temperatures in the Pacific Ocean.

[00:01:59]Um presently, people are expecting it to be very severe by looking at the sea surface temperatures.

[00:02:07]Usually, when the sea surface temperatures are around about 0.2 to 0.9° C warmer on average, it's basically what they refer to as a normal um El Niño. But in this case, it looks like it is going to be more than 2° and some researchers actually say that it could be even worse.

[00:02:31]And of course, there was a couple of these so-called super El Niño occurrences and the last one that we experienced in South Africa was 2015-2016.

[00:02:41]And we will all remember that was also basically the time that the Western Cape basically went to day zero >> Yeah.

[00:02:47]>> because of the severe drought.

[00:02:49]So, these super El Niños really disrupt, of course, the weather patterns all over the world and different parts of the world is affected differently.

[00:03:00]And in our case, we typically see that it is a lot drier um than usual. Where other parts of the world, for instance, in North America, they might experience a serious snowfalls >> Yeah.

[00:03:13]>> and other parts of the world a lot of rain. So, it's really disruptive. And of course, these disruptions, especially combined with what's happening in the world at the moment with the war in Iran and the shortages of fuel, could really have very, very serious implications for the world.

[00:03:31]>> Yeah, and I mean, with global temperatures already at elevated levels, how could a stronger El Niño event further accelerate, you know, warming trends and what world impacts, you touched on it slightly, might this have on regions, specifically such as Southern Africa, including heat waves, drought, or even flooding?

[00:03:53]>> Yeah, look, I mean the the fact that you start getting this tremendous upwelling of um you know, warm ocean water um in the Pacific in areas where it's typically a lot cooler, specifically on the western side of of South America also will of course release a lot more heat into the atmosphere.

[00:04:12]Which of course could result in that 20 27 um might be one of the hottest years that we have experienced so far.

[00:04:22]Combined with the fact that we already sitting at higher global average global temperatures.

[00:04:29]And um regarding what this might have for specifically South Africa is that you know, our farmers and so forth already under pressure due to high diesel prices. And now if we combine this with the potential of a severe drought um food security might become a a major concern. And of course we already have a lot of people in South Africa that are hungry. And I think that we have to be very careful. I mean I'm speaking completely out of my field now that we might actually start seeing civil unrest if this is really as serious as what are predicted to might actually occur.

[00:05:10]>> Yeah. And I mean can you explain to us, you know, in practical terms how El Niño disrupts a normal weather systems, you know, for example how a change changes in the Pacific Ocean temperatures can influence rainfall patterns. I mean thousands of kilometers away such as you know, reduced rainfall in parts of the continent or increased storms elsewhere. Am I correct?

[00:05:36]>> Yes. Now, to try and explain it very simply, you know, usually where oceans are warm, you develop um you know, low pressure systems and of course then the the air will rise, and when it's cold, the air will come down, and that creates more high pressure systems. Now, the the usual situation is that you will have warm water towards the eastern or the western side of the Pacific Ocean, close to places like Indonesia [clears throat] and so forth, and colder water on the western side of South America. And that sets up a a circulation pattern where, of course, the the air is rising on the side of Indonesia, for instance, and the air is sinking on the side of South America. And that creates a circulation pattern, which we refer to as the Walker circulation. And you can imagine, if you think about boiling water in a pot, where it's hot, the water comes up, and when it's cooler on the on the sides, it goes down. Okay, and that, basically, in a very simple term, how, you know, um climate systems are driven by this hot and cooler parts in the Pacific Ocean.

[00:06:48]Now, every couple of years, for various reasons, and I'm not going to go into that, um this whole system is disrupted because it is mainly maintained by wind going from the east to the west over the Pacific that causes the upwelling of the hot water on the western side of the Pacific Ocean. But sometimes these trade winds get weakened, which then results in this hot water moving over the surface, and then upwells, yeah, you know, um so-called Kelvin waves on the western side of South America. And now you can imagine what's going to happen, cuz now suddenly you've got warmer water where it used to be colder. That means that this whole Walker circulation pattern is disrupted.

[00:07:33]So, this these convection cells start shifting.

[00:07:37]And that is, you know, impacts all over the world, because not only is the Walker circulation affected, but also the Hadley cells. But I mean this is getting really technical into the field of meteorology. But it causes shifts in climate patterns all over the world, which then of course is a complete disruption.

[00:07:54]Um yeah, I mean I can go really deep into this. But I can >> Yeah. And I mean we often hear about, you know, El Niño events typically lasting between 9 and 12 months. I mean, what determines the duration and intensity of these cycles? And you know, is there any scientific consensus, if I can, on whether climate change is making them more frequent or more severe?

[00:08:19]>> Um I don't know, you know, I think, you know, the the whole climate system is so complex that, you know, I think we have to be very careful to say whether climate change is actually making it severe. I think the the fact that, um you know, climate change is something that has happened throughout the history of our planet, and that's why geologists also look at forecasts of climate. But of course, yes, we do have an influence on this, and but it has been changing anyway since the last ice age. Um I don't think that climate change necessarily might make the the the it happen more frequently because this is part of a system. But the the El Niño can actually of course enhance the the effect of climate change, the fact that the Earth is hotter at the moment. But of course, like I said, when this hot water now wells up over a larger area and more heat is released in the atmosphere, it means that um temperature would be raised significantly all over the world during this time that it's going to last.

[00:09:20]Of course, you know, scientists look at the surface heat at a couple of locations, and they base, you know, the predictions on this. Um and it looks like, you know, typically that's where the name El Niño of course comes from, or little boy, because it typically peaks in in around Christmas and you know in the South Americans were seeing this for years so they said birth of Christ little boy El Nino. Um it looks like it will peak again around about December but you know and then of course it will start going down and whether this is going to how quickly this is going to happen that is all open to debate you know and of course at the moment predictions say that that this might happen but we've also seen um in the last season when we actually had a a La Nina that um it's very difficult to predict how quickly changes happen um until they actually happen. The system is so big that it's it's really difficult to to try and predict these things.

[00:10:18]>> 100% thank you very much Dr. Herman van Niekerk who's a senior lecturer in the Department of Geology at the University of Johannesburg speaking to us about the potential impacts of a strong El Nino event. We really do appreciate your time here on SABC News. Thank you very much indeed for that.