The weather bureau has just declared an El Niño

After months of anticipation, weather authorities have officially declared an El Niño event active in the Pacific. This natural climate pattern is characterized by warming sea surface temperatures and changes in wind patterns across the Pacific Ocean, directly impacting weather systems globally. During El Niño, the trade winds that normally blow from east to west along the equator weaken, causing a shift in storm activity that can pull moisture and rain away from regions like Papua New Guinea. Historically, major El Niño events have brought severe droughts, water shortages, and devastating frosts to Papua New Guinea. The Bureau of Meteorology officially declared El Niño on June 16, noting that past events have coincided with some of the driest and hottest weather recorded in the Pacific and Australia. El Niño events occur about every three to seven years and can last from six months to two years, typically ramping up in winter and spring before easing in autumn. The declaration requires scientists to observe at least three specific criteria: sea surface temperatures in the central Pacific Ocean must be greater than 0.8°C above average, trade winds must be weaker than average for the past four months, and the Southern Oscillation Index must be lower than -7. Additionally, most global seasonal forecasting models must predict warm ocean temperatures for at least three months. While the declaration signifies current conditions, it is not a forecast. On average, past El Niño events have been associated with warmer maximum temperatures and drier winter and spring conditions across Australia, particularly in the east. The north of the country tends to experience fewer tropical cyclones and a delayed monsoon season. Counterintuitively, El Niño can also lead to colder minimum temperatures and increased frost due to less cloud cover.