How often do you mow your lawn in winter? It may seem like an odd way to start a conversation about drought, but the answer helps explain why our current drought has not broken, despite recent rain \u2013 and why spring lamb may be more expensive this year.<\/p>\n
Southern Australia has been short of rain for 16 months. Western Victoria, the agricultural regions of South Australia<\/a> (including Adelaide) and even parts of western Tasmania are suffering record dry conditions. Those rainfall measurements began in 1900 \u2013 126 years ago.<\/p>\n Serious deficiency means among the driest 10% of such periods on record, severe deficiency means among the driest 5%. Illustration: Bureau of Meteorology\/The Conversation<\/p>\n Fewer and less intense rain-bearing weather systems have been crossing the southern coastline since February 2024 compared with normal. Put simply: the land has not received enough big dumps of rain<\/a>.<\/p>\n But June has finally brought rain to some drought-affected regions; there\u2019s even an emerald green tinge to the fields in certain agricultural areas. But it\u2019s now too cold for plants to really grow fast<\/a>, meaning farmers will be carting hay and buying extra feed for livestock until the weather warms in spring.<\/p>\n Too little, too late<\/p>\n This month, some areas received good rainfall<\/a>, including places near Melbourne and, to a lesser degree, Adelaide. City people may be forgiven for thinking the drought has broken and farmers are rejoicing. But drought is not that simple.<\/p>\n Unfortunately, the rainfall was inconsistent, especially farther inland. The coastal deluge in parts of southern Australia in early June didn\u2019t extend far north. Traditionally, the start of the winter crop-growing season is marked by 25mm of rain over three days<\/a> \u2013 a so-called \u201cautumn break\u201d. But many areas didn\u2019t receive the break this year.<\/p>\n The lack of rain (meteorological drought) compounded the lack of water in the soil for crops and pasture (agricultural drought). Parts of Western Australia, SA, Victoria, Tasmania and southern New South Wales had little moisture left in their soils<\/a>. So some rain is quickly soaked up<\/a> as it drains into deeper soils.<\/p>\n To make matters worse, autumn was the warmest on record<\/a> for southern Australia, after its second-warmest summer on record. This can increase the \u201cthirst\u201d of the atmosphere<\/a>, meaning any water on the surface is more likely to evaporate. Recent thirsty droughts, such as the 2017\u20132019 Tinderbox Drought in NSW<\/a>, were particularly hard-hitting.<\/p>\n Some areas may have experienced \u201cflash drought<\/a>\u201d, when the landscape and vegetation dry up far quicker than you would expect from the lack of rain alone. By May, areas of significantly elevated evaporative stress<\/a> were present in south-eastern SA, Victoria, southern NSW and northern Tasmania<\/a>.<\/p>\n Wilmington in South Australia in December 2024. Photograph: Rural Aid<\/p>\n In late May<\/a> and early June \u2013 and again this week \u2013 there have been winter dust storms<\/a> in SA. Such dust storms are a bad sign of how dry the ground has become.<\/p>\n Some regions no longer have enough water to fill rivers and dams (hydrological drought). Water restrictions<\/a> have been introduced in parts of south-west Victoria and Tasmania<\/a>. The bureau\u2019s streamflow forecast<\/a> does not look promising.<\/p>\n A green drought<\/p>\n Remember that lawnmowing analogy? The winter chill has already set in across the south. This means it\u2019s simply too cold for any vigorous new grass growth and is why you are not mowing your lawn very often at the moment.<\/p>\n Cool temperatures, rather than just low rainfall, also limit pasture growth. While from a distance the rain has added an emerald sheen to some of the landscape, it\u2019s often just a green tinge. Up close, it\u2019s clear there is very limited new growth; rather than abundant and vigorous new shoots, there\u2019s just a little bit of green returning to surviving grasses. This means very limited feed for livestock and, to make matters worse, sometimes the green comes from better-adapted winter weeds<\/a>.<\/p>\n There will be a lot of hay carting, regardless of rainfall, until spring, when the soils start to warm up once again and new growth returns. This all adds up to fewer stock kept in paddocks or a big extra cost in time and money for farmers \u2013 and, ultimately, a more expensive spring lamb barbecue.<\/p>\n Is this climate change?<\/p>\n Southern Australia (southern WA, SA, Tasmania, Victoria and southern NSW) used to experience almost weekly rain events in autumn and early winter; cold fronts and deep low-pressure systems rolling in from the west brought the bulk of the rainfall<\/a>.<\/p>\n Now there is a far more sporadic pattern in these regions. Rainfall in the April to October crop and pasture growing season has declined by approximately 10% to 20% since<\/a> the middle of last century. The strongest drying trend is evident during the crucial months between April and July<\/a>.<\/p>\n Further reductions in southern growing season rainfall are expected by the end of this century, especially in south-western Australia. South-eastern regions, including southern Victoria<\/a>, parts of SA and northern Tasmania, also show a consistent drying trend<\/a>, with a greater time spent in drought every decade.<\/p>\n The decile map shows where rainfall is above average, average, or below average for this period compared to all years from 1900 (when reliable national rainfall records began) to 1993. Photograph: Bureau of Meteorology\/The Conversation<\/p>\n Drought is complex. Just because it\u2019s raining doesn\u2019t always mean it has rained enough, or at the right time, or in the right place. To make matters worse, a green drought can even deceive us into thinking everything is fine.<\/p>\n Breaking the meteorological drought will require consistent rainfall over several months<\/a>. Breaking the agricultural drought will also require more warmth in the soils. Outlooks suggest we may have to wait for spring<\/a>.<\/p>\n Andrew B. Watkins is an associate research scientist at the school of Earth, atmosphere and environment at Monash University<\/p>\n<\/li>\n Allie Gallant is an associate professor at the Australian Research Centre of excellent for weather of the 21st century at Monash University<\/p>\n<\/li>\n Pallavi Goswami is a postdoctoral research fellow in atmospheric science at Monash University<\/p>\n<\/li>\n This article includes scientific contributions from David Jones<\/a> and Pandora Hope<\/a> from the Australian Bureau of Meteorology.<\/p>\n<\/li>\n\n