SYSTEMS CHANGING CLIMATE
Facing up to increased climate variability As the north warms researchers are looking across the Tasman for suitable alternative forage species. Delwyn Dickey reports.
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orthland, New Zealand and New South Wales in Australia, don’t look that much alike. Red earth and a bunch of bouncing marsupials are certainly missing from the Kiwi scene. But we have more in common than you might think. As the climate warms, farmers from other parts of the country can look to other districts to see what their future climatic conditions might look like and adapt their farming operations accordingly. But farmers in the north are heading into uncharted territory. Northland already experiences about 55 days a year, between November and April, when soil moisture is too low to maintain plant growth without irrigation, according to the National Institute of Water and Atmospheric Research (NIWA). With an extra 20 to 30 days a year with 36
temperatures over 25 Celsius likely by 2040 and a whooping 40 days a year possible in 70 years, the Northland climate is moving into a league of its own, with no comparable area we can look to for climatic conditions. Unless we look across the Tasman. “Northern New Zealand’s climate is becoming more similar to central and southern Victoria’s,” Professor Yani Garcia with the University of Sydney told delegates at the Resilient Pastures Symposium recently. “In the future it may be more similar to current central and northern New South Wales (NSW).” The modelling systems used showed that while the climatic suitability for dairy of the mid and north coast of NSW and South East Queensland clearly decreases by 2050, it improves markedly for Tasmania and the Manawatu, and even more so for Canterbury and parts of Southland.
Professor Yani Garcia from the University of Sydney.
By 2050 these models show Northland with a similar climate to the Sydney Basin today, Garcia says, and to the NSW coastline areas more generally, with Waikato’s climate similar to Northland today. Rainfall is becoming more irregular and unpredictable, with Victoria, NSW and Queensland particularly, being hit hard by two unprecedented extreme droughts in
Dairy Exporter | www.nzfarmlife.co.nz | September 2021
