Farmers across Western Queensland are increasingly turning to scientific data to navigate a changing climate, with new analysis revealing significant shifts in regional weather patterns over the past five decades. This proactive approach is empowering producers to adapt traditional farming methods, ensuring the resilience and profitability of their operations.

Climate's Clear Shift Evident in Decades of Data

Scientists have meticulously examined 50 years of comprehensive weather records from key Western Queensland towns, including Boulia, Longreach, Barcaldine, Tambo, Birdsville, Blackall, Winton, and Windorah. The findings paint a clear picture of an evolving climate:

• Significantly hotter summers that are also extending for longer periods.
• A marked increase in the number of hot days and a reduction in cool nights.
• A discernible shift in seasonal timings, particularly concerning rainfall patterns.

Dr. Mahdiyeh Razeghi, an earth scientist at the University of Southern Queensland, underscored the clarity of these observations. "Our analysis specifically focused on critical indicators such as temperature, the frequency of hot days, the scarcity of cool nights, the timing of rainfall, evaporation rates, and the prevalence of extreme heatwaves," Dr. Razeghi explained. "The results unequivocally demonstrate a trend of more frequent heat extremes, fewer cool nights, and a definite alteration in seasonal cycles, particularly impacting rainfall timing across most of the studied towns."

Farmers Innovate Breeding Schedules for Survival

For wool producers like Peter and Kimble Thomas, who manage a 12,000-head merino enterprise near Ilfracombe, these climate shifts are not just statistics but daily realities shaping their livelihood. Traditionally, their lambing schedule involved lambing in May, but as summers intensified and prolonged, lamb survival rates began to suffer.

"We weren't getting great lamb survival coming out of the summer, lambing into May," Mr. Thomas recounted. In response, the Thomases trialled a new approach, shifting a portion of their ewes to a later joining, resulting in lambing in August. This strategic change ensured the majority of the ewes' pregnancy occurred during the cooler months of the year.

The trial yielded impressive results, with lamb survival rates increasing by a significant 20 per cent last year. While acknowledging that one positive season doesn't confirm a permanent trend, the improvement was compelling enough for the Thomases to commit to continuing the adapted schedule. "The heat effect of having our sheep pregnant over those hot summer months was a major concern," Mr. Thomas stated, highlighting the data-driven decision to overhaul their breeding calendar.

Bridging Data and On-Farm Decisions

The integration of climate data into practical farming decisions is being facilitated by initiatives like the UniSQ-led Southern Queensland and Northern New South Wales Innovation Hub. Bruce McConnel, the director of the hub, supervised the development of a Climate and Weather Trend Analysis tool specifically designed for Western Queensland grazing enterprises.

"While it's always been hot out here, the data shows it's now hotter for longer, and crucially, slightly hotter overnight," Mr. McConnel noted. "This information empowers producers to make more informed choices, such as moving lambing into an autumn period with a warmer winter, leading to better weight gains and a more productive, resilient system."

Further insights from the analysis reveal that the traditionally defined summer period is now stretching beyond its conventional boundaries. Geoff Penton from Desert Channels Queensland, a natural resource management group working to disseminate this vital data, elaborated on the extensions. "We’ve seen significant temperature increases during months like September, October, March, and April," Mr. Penton explained. "Across many of these towns, over the 50-year period, there's an increase of eight or nine days a month above 35 degrees Celsius in months such as October."

The rise in night temperatures is equally critical for livestock health and productivity. "The heat stress doesn't dissipate as much overnight, which can significantly impact live weight gains, fertility, and overall production," Mr. Penton warned. "This directly affects issues like calf and lamb survival, exacerbating heat stress and hydration challenges, ultimately impacting weaning rates and profitability."

Adapting for Enduring Productivity

Peter Thomas, initially skeptical about climate change, now fully embraces the need for adaptation. "In the past, I've been a bit dismissive about the changing climate, probably because of the year-to-year and season-to-season differences that masked the larger trends," he reflected. "But these observations clearly demonstrate how things have gotten hotter during specific times or months."

The Thomases recognise that adaptation, while necessary, often involves compromise. "We're avoiding a lot of sheep activity and pregnancies over the most intense heat, moving them to more favourable months," Mr. Thomas said. "The compromise is that we'll be lambing onto pasture that might not be as lush as what we’d see in May." Despite this, they view it as a calculated risk they cannot afford to ignore.

"It's not going to get any cooler or more favourable, so we simply have to adapt," Mr. Thomas concluded, emphasising the continuous need for improvement. "We must continually enhance our productivity just to stay in business and keep ahead of inflation. Any research into animal production or pasture management that can help us do that is incredibly valuable." Their journey exemplifies the proactive and data-driven approach essential for agricultural sustainability in a changing climate.