Climate

Pressures

In the years since the Bureau of Meteorology records began in 1942, annual average air temperatures at the Cairns Aero Station have trended up by about 1 °C. 2021/22 was a warmer than average year, with an average annual maximum temperature of 30.5 °C, 1.4 °C higher than the average since 1942. Additionally, there were 12 days recorded over 35 °C, twice as many as the previous year, and far exceeding the average of 3.3 days per year. The average annual minimum temperature was high as well, at 22 °C, compared to the all-years average of 20.8 °C.

In 2021/22, rainfall at Cairns Aero Station was 32% below the previous year and 11% below the average since 1942, with records showing just 1,729.2 mm over the year.

Higher than average ocean temperatures led to a marine heatwave in February 2022, with mass coral bleaching observed across 91% of the Great Barrier Reef (GBR). This was the fourth such event since 2016, and the first to occur during a La Niña cycle, normally associated with cooler waters. The Great Barrier Reef Marine Park Authority’s Reef Snapshot described the pattern of bleaching across the region around Cairns as varying from major to severe. Much of the coral is expected to recover in the absence of further heat stress.

The ocean continues to absorb most of the heat caused by greenhouse gases, which can cause ocean acidification and sea level rise - the latter increasing risks to coastal infrastructure, community values and ecosystems.