Australia & New Zealand: Intense water deficits forecast for Tasmania, Top End NT, & New Caledonia

28 May 2019

THE BIG PICTURE
The 12-month forecast through January 2020 shows widespread, exceptional water deficits in Northern Territory reaching west to the Hamersley Range in Western Australia and north through the Kimberley region. Exceptional deficits are also forecast in Western Australia’s southern tip, with deficits of lesser intensity reaching north past Perth.

Moderate to extreme deficits are forecast along Australia’s southeastern coast from Adelaide past Melbourne, and deficits will reach exceptional intensity in Tasmania.

Primarily moderate deficits are expected scattered along the country’s eastern coast and through much of the Cape York Peninsula in the north, punctuated by some pockets of greater intensity between Sydney and Brisbane and near Rockhampton in Queensland.

Moderate surpluses are forecast for northeastern Queensland south of Townsville and northwestern Queensland east of the Selwyn Range. Intense surpluses are forecast in southeastern Northern Territory east of the MacDonnell Range.

Severe deficits are expected in New Zealand’s North Island, and deficits of varying intensity in pockets of South Island. In New Caledonia, exceptional deficits are forecast.

FORECAST BREAKDOWN
The 3-month maps (below) show the evolving conditions in greater detail.

The forecast through July indicates that widespread, exceptional deficits that have dominated much of Australia in prior months will shrink considerably. Exceptional deficits are, however, forecast in Top End, Northern Territory (NT) reaching west to the Ord River in Western Australia (WA), with primarily severe deficits throughout the Kimberley Region, moderating south through the Great Sandy Desert. Severe to exceptional deficits will trail around the southern shore of the Gulf of Carpentaria into Queensland (QLD) leading to moderate deficits just south of Cape York Peninsula. Some pockets of moderate surplus are forecast in the northeast just west of Cairns and south of Townsville in QLD.

In Australia’s southeastern quadrant, deficits of varying intensity are expected following the coast from Adelaide in the south to Brisbane in the east, with severe to extreme deficits near Melbourne and between Sydney and Brisbane. Moderate deficits are forecast for the Lachlan and Macquarie Rivers in New South Wales (NWS). Deficits will be intense in Tasmania. Intense deficits will increase in WA’s southwestern tip. In the center of the country east of the MacDonnell Range in NT, a large pocket of exceptional surplus will begin to transition, with conditions of both deficit and surplus (purple).

In New Zealand, severe to exceptional deficits are forecast for North Island, and some pockets of primarily moderate deficit in South Island. Deficits in New Caledonia will be extreme to exceptional.

From August through October, exceptional deficits will increase in northern NT and deficits will intensify in the Fitzroy and Ord River regions of northern WA, becoming exceptional. Severe deficits will persist in the Kimberley. Exceptional deficits will emerge in the tip of Cape York Peninsula. Deficits in WA’s southwestern tip will shrink and downgrade but will be severe. Along the southeastern coast of the country, deficits will moderate from Adelaide to Brisbane, but deficits will be severe in Tasmania. Exceptional surpluses are expected to re-emerge east of the MacDonnell Range in southeastern NT. Some moderate deficits are forecast for New Zealand and deficits in New Caledonia will downgrade from exceptional to severe.

The forecast for the final months – November 2019 through January 2020 – indicates moderate deficits across northernmost Australia, and some severe deficits in the southwestern tip of WA and in Tasmania. Some moderate deficits are expected in New Zealand and New Caledonia.

(It should be noted that forecast skill declines with longer lead times.)

IMPACTS
Australia will be importing a rare bulk wheat shipment from Canada this year, likely due to the prolonged drought in the country’s east. It will be the country’s first wheat import in over a decade. Drought has ravaged eastern Australian agriculture, creating one of the most expensive wheat markets in the world, recently at A$300 (USD $206) per ton. Importers who have typically bought Australian wheat are turning to other suppliers like countries in the Black Sea region; Indonesia, the world’s second-largest importer, bought record wheat supplies from Russia and Ukraine.

Eastern Australian wheat production is down about 45 percent from last year, causing the country’s largest bulk grain handler to suffer losses of $59m (USD $40.8 million).

Rainfall from ex-Tropical Cyclone Trevor moved through western Queensland’s waterways early this month, flooding catchments down into southern Queensland with floodwaters and filling the hearts of locals in South Australia with delight.

Dam levels in greater Sydney are dropping faster than they have in decades, prompting the city to consider implementing water restrictions if drought conditions don’t ease in the next few months. Since April 2017, water levels have dropped from 96 percent capacity to 55 percent capacity. if levels drop to 50 percent, Sydney households will be prohibited from hosing hard surfaces and be limited to watering gardens only during certain hours.

NOTE ON ADMINISTRATIVE BOUNDARIES
There are numerous regions around the world where country borders are contested. ISciences depicts country boundaries on these maps solely to provide some geographic context. The boundaries are nominal, not legal, descriptions of each entity. The use of these boundaries does not imply any judgement on the legal status of any territory, or any endorsement or acceptance of disputed boundaries on the part of ISciences or our data providers.

Subscribe to our monthly Water Watch List

Search blog categories

Search blog tags