Forecasting more than just rain

While those on the land definitely want to know about a developing El Nino, what they’d much prefer is a model for predicting liveweight gains.

As advanced as that may seem, it is actually in the sights of Australia’s senior scientists.

The future of climate modelling is in a detailed, tailored product that covers the key climate factors of individual cattle-producing regions including the expected pasture growth from predicted rainfall.

That will form the basis of an integrated system, incorporating analysis of data on everything from soil moisture and the quality of the pasture the year before to the current condition of stock, to predict liveweight gains.

Producers will be able to run simulations of different management strategies for the year ahead to estimate how much beef they can produce.

The CSIRO, with skills across real time soil moisture measurement, climate, agriculture, livestock, land and water and data analysis, has the tools to make it happen - the challenge is putting it all together and tailoring it to each region, according to CSIRO senior ocean research scientist Dr Jaclyn Brown, based in Hobart, Tasmania.

Dr Brown has been working on determining the value of season prediction models for the livestock industry under Meat and Livestock Australia’s investment in the Managing Climate Variability program.

Her first case study was the El Nino-dominated Dalrymple region of North Queensland and she is about to kick off an investigation of the Central Australian monsoon country around Victoria River Downs.

What she is finding is that climate prediction in Australia is more than just knowing whether it is going to be an El Nino year and what the rainfall forecast is.

“Rainfall isn’t necessarily what beef producers need forecasts of,” she said.

“It’s more useful to have a forecast of pasture growth and when in the year that pasture might grow.”

Speaking at a beef industry breakfast hosted by MLA in Brisbane, Queensland, this week, Dr Brown said early season pasture growth made a big difference to what producers could bank on in terms of producing beef in the Dalrymple study.

“It’s not the total rainfall that producers are making decisions on but rather when it falls,” she said.

“In an El Nino, there is rarely rain in winter but in a neutral year or a La Nina there can be early rain and being able to predict that early rain will make a big difference to overall liveweight gains.”

Historical data from the region showed years when liveweight gain was similar despite rainfall during the key July to March period varying to the tune of 400mm.

“So predicting winter rain will be more useful to the beef producer in El Nino-dominated regions,” Dr Brown said.

“But the key thing is, there is not one size that fits all across Australia.

“We need to replicate this work throughout all cattle-producing regions in order to develop models that are tailored to the key climate factors of each region.

“What producers want is certainty. We won’t be able to do that but we need to bridge the gap between what we can do and what producers need.”

Dr Brown said another point was that looking at past climate patterns was not necessarily going to be useful anymore.

“Climate change has altered our system and now it behaves in new ways we are still learning about,” she said.