As the 2015 Australian Open Tennis tournament gets underway in Melbourne, the organisers have updated their extreme heat policy to "ensure conditions are fair for all players". A roof has also been added to a third court.
The extreme heat policy is implemented at the referee's discretion. Once the policy is introduced, play can be suspended at the end of the current set in each match, or after an even number of games in the set have been played. Under previous guidelines, there was no set temperature to trigger the extreme heat policy, with the decision left entirely to referee's discretion. This led to criticism during the January 2014 tournament that the policy was not implemented transparently, with players complaining of "dangerous" and "inhumane" conditions.
The new heat policy takes into account the forecast once the ambient temperature exceeds 40°C, and the Wet Bulb Global Temperature reading (which takes into account humidity and wind direction as well as heat) exceeds 32.5°C. Above these levels, players are likely to absorb significantly more heat than they give off, leading to a risk of heat exhaustion.
Humidity is also an important factor, as moisture in the air inhibits the evaporation of sweat, the body’s first line of defence against overheating. Fluids lost to sweating need to be replaced, but this can be difficult under match conditions, meaning that overheating players also risk dehydration.
Australia has recently experienced its hottest month and hottest spring on record. In a report on the BBC Australia website, scientists are predicting that due to climate change, much of Australia will be subjected to longer, hotter and more regular spells of hot weather. According to Elizabeth Hanna, President of health sector organisation the Climate and Heath Alliance, Australian sporting authorities will need to start ‘heat-proofing’ their operations and need to rethink when and for how long competitions are played outside.
In the longer term, other sports such as cricket and long-distance road events such as running and cycling may also have to adapt to climate change.