Bureau of Meteorology Declares El Niño Underway in Tropical Pacific

The Bureau of Meteorology declared on Tuesday that an El Niño is now underway in the tropical Pacific Ocean. The agency said the atmosphere has begun reacting to higher than average sea surface temperatures, with weakening east-to-west trade winds and pressure and cloud patterns consistent with the pattern. Forecasts point to a strong or very strong event, the bureau stated.

It noted that the strength of an El Niño is measured by sea surface temperatures in a defined region of the tropical Pacific and how far those temperatures exceed the long-term average. The bureau said past El Niño events have coincided with lower winter and spring rainfall across Australia’s eastern half, higher daytime temperatures in southern Australia, and an increased frost risk due to clearer skies.

It added that the strength of the event does not necessarily mean strong impacts on Australia’s climate.

U.S. government’s National Oceanic and Atmospheric Administration and the Japan Meteorological Agency have already declared the El Niño, though both use slightly different methods and thresholds than the Bureau of Meteorology. The bureau said the rise in ocean temperatures in the tropical Pacific has been rapid in recent months.

5C hotter, the bureau stated. It said the event is emerging in this warmer baseline and that unprecedented ocean temperatures are likely. The Climate Council described El Niño and greenhouse gas emissions from fossil fuels as a “dangerous double act” for Australia.

The bureau warned that climate change would amplify the effects on Australia, including the risk of extreme heat and bushfires. It also noted that El Niño events are linked with extreme weather around the world and can increase the risk of bushfires and coral bleaching on the Great Barrier Reef.