Climate

Month    Average Temp °C     Average Rainfall mm
January      27.5                              405.4
February     27.4                              434.2         
March        26.75                             424.3
April          25.35                              197.9
May           23.7                               99.1
June          22.7                               49.1 
July           21.3                               30.0
August       22                                  27.4
September 23.2                                35.3
October     24.95                               38.3 
November  26.4                                89.4
December  27.35                               175.6

The Great Barrier Reef has a tropical climate, with average temperatures in summer of between 24 and 33 degrees Celsius, in winter 14 to 26 degrees. Being a wet tropic climate, there are only 2 seasons, 'the green' and 'the dry'. The green season stretches from the first of the monsoonal rains (75% to 90% of the region's rainfall falls in the green season), usually in November, and ends in May. The region averages over 300 days of sunshine per year.

 

The Great Barrier Reef Marine Park Authority considers the greatest threat to the Great Barrier Reef to be climate change, causing ocean warming which increases coral bleaching. Mass coral bleaching events due to elevated ocean temperatures occurred in the summers of 1998, 2002 and 2006, and coral bleaching is expected to become an annual occurrence.  Climate change has implications for other forms of reef life—some fish's preferred temperature range leads them to seek new habitat, thus increasing chick mortality in predatory seabirds. Climate change will also affect the population and sea turtle's available habitat.