28
BAMOS
Mar 2019
Article
Could Rising Temperatures Kill the
Priestley Cup?
Kimberley Reid
The Priestley Cup is the annual round robin soccer tournament
between Melbourne University, Monash, CSIRO and the Bureau
of Meteorology. It’s an afternoon of friendly competition
followed by pizza and drinks—a highlight on the AMOS
Melbourne Chapter calendar. After winning the Cup in 2016
and 2017, Melbourne University were vying for the hat-trick,
but no team name will be engraved on the trophy for 2018.
The tournament was supposed to be held on 7 December
2018, however due to a forecasted maximum temperature
for Melbourne of 38 °C, it was rescheduled for 1 March 2019.
Three months after cancelling and rescheduling the Priestley
Cup because of hot weather, the AMOS Melbourne Committee
agreed to cancel the event again due to a forecasted maximum
temperature for Melbourne of 37 °C.
The sequence of events had many keen AMOS soccer players
scratching their heads. What are the odds of two 37+ degree
days coinciding with the Priestley Cup in one year? Using the
daily maximum temperature data from AWAP already saved on
my computer, I decided to do the maths*.
I selected a 0.25° x 0.25° grid space over the University of
Melbourne, where the Priestley Cup is held, and counted the
number of days between November and March with a maximum
daily temperature (T max ) equal to or greater than 37 °C for a 30-
year period (1984–2014).
1. P(T max >= 37 on any day)=
= 0.0228
Equation 1 says that the probability of the maximum
temperature exceeding 37 °C on one day between November
and March is about 2%. But, the 2018 Priestley Cup’s fate was
sealed by two extremely hot days.
2. P(T max on two independent days >=37) = 0.0228 x 0.0228
= 0.00052
Number of days with a maximum
temperature equal to or greater than
35 °C, 1984–2017, at a grid space over
the University of Melbourne
Equation 2 tells us that the chance of the Priestley Cup being
cancelled twice in one year is 0.05%. In other words, you have a
higher chance of being born with an extra pinky finger than for
the Priestley Cup to be cancelled twice in one year due to two
37 °C+ days (Buck-Gramcko, 1998).
I repeated the calculation for 35 °C and above days, since it’s
likely we’d cancel the Priestley Cup under those conditions too,
and found the probability of the Priestley Cup being cancelled
twice in one year rose to 0.5%.
The graph below shows the number of days with a maximum
temperature at or above 35 °C from 1984–2017, at a grid
space over the University of Melbourne. While there is high
interannual variability, the long-term trend is clear, Melbourne
is experiencing more hot days. With this trend likely to continue
under a warming climate, the chance of the Priestley Cup being
cancelled will increase too…unless we move it to winter.
Reference
Buck-Gramcko, D., 1998. Congenital Malformations of the Hand
and Forearm. Churchill-Livingstone.
*This analysis is for entertainment purposes and is not
peer-reviewed.