CLIMATE research has confirmed that the weather across the Wheatbelt is warming but not enough to bid farewell to frost.
An analysis of spring temperatures over the past 50 years across the region will be presented at the Department of Agriculture and Food’s Agribusiness Crop Updates, supported by the Grains Research and Development Corporation (GRDC) later this month.
Department research officer Ian Foster said the research, funded by The Department and GRDC, confirmed expectations of a warming trend across the region and that the risk of high temperature events were increasing.
However, the results relating to the incidence of frost were patchy.
The nineteen sites analysed, identified as most at risk of frost, ranged from Dalwallinu to Bencubbin and Katanning to Lake Grace and Salmon Gums.
Dr Foster said while spring minimum temperatures had increased by 0.5 °C across most of the State, the results showed that trends in more extreme temperature events had varied by location for the wheatbelt.
“Sites with stronger warming trends in spring, like Pingelly and Narrogin, showed a consistent decline in the risk of frost temperatures below 2°C,” Dr Foster said.
“However, those sites with a smaller warming trend or even cooling, such as Northam or Kellerberrin, showed an increase in frost risk.
“It’s interesting to note that the results were very scattered and there was no regional spread of consistent trends.
At half the sites, the last frost occurred earlier in the season but extended later by over a week at four other sites. There does not appear to have been a consistent decrease in frost risk in recent decades.”
The analysis also found there was an increase in the number of days with a maximum temperature of 34°C or more across the region.
“Most sites showed a positive trend in seasonal maximum temperatures, as well as a general increase in the risk of high temperatures,” Dr Foster said
The analysis found there also appeared to be little relationship between spring temperature trends and seasonal rainfall.
The research will help plant breeders develop more robust varieties and agronomists to develop improved crop management tools, or management options.
Dr Foster and his team now intend to investigate any correlation between locations, as well as defining how temperature risk changes under future climate scenarios to 2050.
The Department for Agriculture and Food’s 2012 Agribusiness Crop Updates, is on 28 and 29 February at the Pan Pacific Hotel in Perth.
