At temperatures above 35 degrees the human body’s ability to cool itself reduces, making it a common benchmark temperature for occupational health and safety experts, academic and government researchers.
The number of days over 35 degrees per year in Roma has nearly doubled from an average of 42 days per year from 1992–1997 to 68.5 days per year over the last five years. The amount of these extreme heat days could more than quadruple to a projected 185 days over 35 by 2090.
Days over 40 degrees are also projected to increase from a current average of four to five days per year to as high as 84 days annually by 2090.
Alarmingly, CSIRO and Bureau of Meteorology (BoM) projections also demonstrate an increase in the frequency of hot nights. Unless emissions are decisively reduced, CSIRO and BoM project about half of summer nights could be over 25 degrees by 2070 in Roma.
The impacts of more extreme heat are already being seen globally, with Europe, Russia, India and Pakistan all experiencing heat waves resulting in thousands of deaths.
Increased hot days would reduce productivity in important Queensland industries such as agriculture, construction and tourism. Roma specifically would see its large employment sectors of livestock and wheat crops greatly damaged.
Fortunately, CSIRO projections show that if emissions are reduced, the rises in extreme temperature days will be far lower. For instance, with a decisive reduction in emissions the rise in 40 degree days could be kept to around one third of the rise that could be expected otherwise.