The Bureau of Meteorology (BOM) has recently announced a third La Niña, which may mean increased rains and risks of flooding on already saturated lands. A triple La Niña is not unprecedented, with two former examples occurring in 1998–2001 and 1973–1976.

UNSW experts are available to discuss the genesis of La Niñas, the historical precedents of triple events, the context in terms of climate change and the consequences for flooding.

  • Scientia Professor Matthew England from the UNSW Climate Change Research Centre says that a triple La Niña means a third summer in a row with increased likelihood of flooding rains and tropical cyclones.  He said in addition to that is a global warming signature, which has warmed the surface of the ocean globally by nearly a full degrees Celsius, which increases the moisture content of the atmosphere and further raises the chances of extreme flooding rain events.
  • Dr Nina Ridder is a research associate in the UNSW Climate Change Research Centre. Dr Ridder can comment on the general atmospheric conditions during a La Niña, and how it is related to rainfall and flood risk in Australia. She has unique insights into the risk of preconditioned events caused by rain on saturated soils and the occurrence of multiple heavy rainfall events affecting the same region in close succession, leading to floods that would not have occurred if the region hadn’t experienced above normal rainfall in previous seasons as seen in NSW in March and July this year. 
  • Dr Agus Santoso is a senior research associate at UNSW Science’s Climate Change Research Centre. Dr Santoso can discuss why La Niña happens, how it evolves, its being influenced by climate change and what the future holds for La Niña and El Nino. Contact: a.santoso@unsw.edu.au.
  • Professor Ashish Sharma from the UNSW School of Civil and Environmental Engineering can comment on the flooding implications of La Niña. He is an engineering hydrologist whose research is focused on the impact of climate change and variability on hydrological practice, developing hydrological models, designing flood estimation and water resources management. Contact: a.sharma@unsw.edu.au.
  • Dr Andrea Taschetto is a climate scientist and Associate Professor at UNSW Science’s Climate Change Research Centre, and a chief investigator at the ARC Centre of Excellence for Climate Extremes. Dr Taschetto can discuss climate variability related to the tropical Pacific and Indian Oceans (for example ENSO and IOD). Contact: Jesse Hawley, jesse.hawley@unsw.edu.au, 0422 537 392.