She detailed her “concerns” in a letter to the game’s governing physique this week.
“To have the opportunity to compete for Great Britain in Australia is a privilege,” she wrote.
“When I started running, the prospect of me competing in the World Cross Country Championships would have seemed merely a dream. However, the reality of the travel fills me with deep concern.
“I used to be simply 9 when the COP21 Paris Climate settlement was signed. Now, eight years on, and world emissions have been steadily growing, sending us on a path to local weather disaster.”
The 16-year-old added she would “by no means be snug” flying and that it would cause her grief.
“Coming to a choice has not been straightforward, nevertheless little compares to the grief I might really feel taking the flight.”
In December, the 16-year-old dominated the European Cross Country Championships in Turin.
She set a national under-17 record for 3000-metres, and finished fourth in the 4000-metre race at the under-20s, going against athletes three years older.
The wins came despite the fact she missed much of her preparation because she was travelling.
Her 20-hour journey to the northern Italian city involved coaches, trains and cycling from station to station.
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FitzGerald has previously ruled herself out of competing at the European Under-18 Championships in Jerusalem.
Her concerns about travelling via aircraft stem from flight emissions; the aviation sector currently accounts for two per cent of emissions globally.
According to the International Civil Aviation Organisation (ICAO), one individual flying from London to Sydney by way of Singapore could be chargeable for 1.74 tonnes of CO2.
Source: www.9news.com.au