Various different research organisations and agencies, both local and international, have been consulted or have made pronouncements on the 2015 El Niño and its impact on southern Africa (especially in light of the current drought conditions) and this has made its way into the public domain through the media. These messages are often inconsistent and vary in their attribution of the current climate conditions in the region to the El Niño phenomenon. The facts are:

1. El Niño is a recurring natural climate phenomenon, while largely unpredictable at long time ranges (it is initiation is observable up to 6 months before) occurs relatively regularly every 2-7 years). It comprises an anomalous relative warming of the eastern Pacific Ocean and cooling of the western Pacific ocean due to a change in wind patterns. The opposite state is called La Niña. Together they are referred to as the El Niño Southern Oscillation (ENSO). The ENSO state (El Nino, La Nina and neutral) are all normal states of the climate system - which oscillates between these states - with each phase lasting between 1 to 2 years. The intensity of the state of ENSO varies (some events are larger in amplitude and longer lasting than others).
2. The ENSO state usually has a significant impact on world weather with extreme events (floods and droughts) occurring in various locations around the world in association with these varying states. The impact of ENSO on southern Africa is not exactly the same from one El Niño to the next, or from one La Niña to the next, but has some general features.
3. Mostly (but not exclusively) El Niño is associated with drought conditions (defined as less than long term average rainfall - these also range from mild to severe) in southern Africa. The size, duration and intensity of El Niño is not well correlated with the intensity and spatial extent of drought (i.e. a big El Nino does not necessarily result in a big impact in our region).
4. The 2015 El Niño is a relatively large event and is comparable to the very signficant1997/8 event. A smaller Niño event did manifest in the summer of 2014/2015 and the drought index for South Africa indicated mild to severe drought conditions over most of the country (i.e. last season's summer drought was mild to severe as measured by decreased rainfall relative to the long term average; the largest since 1995 for southern Africa as a whole) and thus the impact of that drought is what we are experiencing currently. Whether this year's summer half-year will also result in drought (measured as rainfall from October to March) remains to be seen. Rainfall of yesterday and today, for example, are not an indication of the breaking of the current drought cycle - around 100mm of rain consistently on a 10 day cycle is what is required to break the drought. Seasonal weather predictions and current understanding of ENSO suggest that it is likely that the coming mid-summer period of December to February will be associated with above-normal temperatures and below-normal rainfall.
5. Anthropogenic induced climate change, together with natural climate variability and a better understanding of the complex, socio-economic context in which ENSO occurs, are all critical elements to consider when explaining current weather phenomena. It is most likely that the enhanced greenhouse effect is contributing to 2015 being the warmest year on record globally- in combination with the presence of the strong El Niño event.
6. Researchers in South Africa, at the South African Weather Service (SAWS), Council for Scientific and Industrial Research (CSIR) and several universities, are conducting ongoing research into climate dynamics and extreme events (including ENSO and socio-ecological impacts) in order to understand the mechanisms and consequences of climate dynamics in the region on short to long term time scales.
7. Research uses climate models to understand the regional to local scale impacts to global teleconnections on the short (days), medium (weeks), long (seasonal) and multi-decadal (climate change) time scales. The main goal of the research is to develop the tools (and improve the models) to more accurately understand and project climate and various atmospheric interactions at these time scales and ultimately to better understand climate variability and its impact on society and the economy.
8. This El Niño event (and other anomalies) are also important scientific opportunities to test our climate models and learn (with appropriate observations) about their impacts on global climate dynamics and our social and economic system. This helps to improve skill in predicting, projecting and managing future events and prepare us for climate change scale impacts.
9. Although projections of future climate change over southern Africa are robust in some aspects (e.g. likely drastic increases in surface temperature under low mitigation) more uncertainty surrounding other aspects (e.g. rainfall futures over the eastern parts of South Africa) still exists. One important question is the interaction between climate change and El Niño and to understand the mechanisms by which a warmer atmosphere may manifest in regional climate systems (e.g. will a warmer climate result in more frequent and more intense ENSO events?).
10. South African researchers from SAWS, CSIR, various universities and other institutions are teaming up through a variety of research programmes (including ACCESS) to tackle these challenges.