Canberra recorded the highest levels seen in more than 10 years during its 2021-22 pollen season, with experts monitoring the relationship between climate change and pollen closely.
ANU professor and co-creator of Canberra Pollen Simon Haberle said the territory recorded particularly bad results.
"Even compared to other parts like Melbourne and Sydney, and other areas in the south-east of Australia, Canberra had the highest recorded level this year for that season," he said.
The primary cause can be traced back to the La Nina period and ensuing wet weather, which stimulated grass growth throughout spring.
Mr Haberle said grass pollen had dropped off as expected in mid-late January, but the period during which tree pollen is present has extended.
"We have a short period of tree pollen in the air which is also allergenic and that includes the elm trees - the Chinese elms - and Casuarina or she-oaks."
"Those two trees, normally we see them only lasting a couple of weeks around mid-February, but this year, that period of tree pollen has actually extended for at least four weeks."
He said the abnormally long season of tree pollen was due to a very warm, late summer and early autumn.
"This has allowed some of the trees to actually produce flowers and pollen for a much longer period."
"So all this is telling us ... with global warming increasing warmer temperatures that can potentially extend the period of hayfever suffering."
Year-round surveillance was increasingly significant for this reason, Mr Haberle said.
"It's really important that we do keep on monitoring the pollen so we can get a better understanding of how it's changing through the global climate change era."
