Grazing cattle raise a cloud of dust as they scratch for food on a drought affected farm near Goulburn, about 170 km (105 miles) south-west of Sydney in this October 29, 2006 file photo. Across the world, speculators are increasingly looking to water as a new profit engine as supplies dwindle, caught between booming populations demanding more access and climate warming threatening its very availability. To match feature ENVIRONMENT-AUSTRALIA/WATER REUTERS/Tim Wimborne/Files (AUSTRALIA)
REUTERS/TIM WIMBORNE