Australia is struggling with the effects of a five-year drought and no relief appears in sight. As Phil Mercer in Sydney reports on this World Water Day, some Australian experts fear the so-called "Big Dry" may become a permanent climate feature of the country in part due to global warming.

Australia is the world's driest continent. Drought has always been a part of life here.

But, even by Australia's standards, the current spell of extremely low rainfall has been extreme. It has lasted for more than five years so far.

Many towns and cities in the southern half of the continent are subject to severe water restrictions. Those who break the rules face fines of up to $150, and it is thought that more stringent controls on domestic use are only a matter of time.

Farmer Andrew Higham looks over his parched land in north western New South Wales, 14 Oct 2006

Five years is a long time, but experts like Professor Andy Pitman, a climatologist at Macquarie University, say the drought could actually go on for decades.

"The really scary thing is last time we had a drought of this intensity that lasted about five years - it lasted for about 50 years. And I really find it difficult to imagine what Australia would look like - or at least east coast Australia, where the major population centers are - what it would look like if this current rainfall regime was sustained for 40 to 50 years," said Pitman. "The politicians truly believe this is a five-year or six-year drought that will break sometime in 2007 or 2008. It mightn't break 'til 2050."

Conservationists here are linking the drought with global warming. They believe higher temperatures and low rainfall will now become permanent features across the country.

Farmer Gary Hallam says his land has been rendered useless by the drought. He can only hope people like Pitman are wrong, and the "Big Dry" will soon end.

"It's actually like standing on edge of a cliff," he said. "The grass should be a couple of foot high, and green and lush. And as you can see, it's just brown and dust. I'm hopeful that this is a cycle. Because if it is, if this is like the climate change what they're talking about, it'll eventually… make it unsustainable out here, whether you'd like it or not."

Cate Faerhrman from the Nature Conservation Council of New South Wales says the lack of water is likely to force some farming areas to be abandoned.

"We're in a state of emergency. I can imagine Australia being a desert in a few decades' time in some of these rural areas that are currently agricultural areas, they have been not managed correctly," said Faerhman. "The soil is blowing away, the rivers are drying up…Now is the time to look at the way we do these things though, and to see if we can save some of it.".

With harvests destroyed and livelihoods under threat, many typically tough and resilient farmers in the outback are experiencing mental depression. Mental health charities estimate that one farmer takes his life every four days, and special help lines have been set up for those who find it hard to cope.

The government has been sending out "drought buses", giving farmers a mixture of social counseling and advice on water-saving measures.

Jock Lawrie, president of the New South Wales Farmers' Federation, paints a dismal picture.

"You've got to understand that there are people out in some parts of our state that have gone to work for four or five years and haven't even earned an income. And certainly in the last year, with the winter crop failing to the extent it did, there's been some… massive losses," he said. "That combination on top of the drought and not earning any money, it is really hard on the emotions of people, there's no doubt about that."

Australia, which traditionally has some of the world's most erratic rainfall patterns, has experienced extremely dry periods before.

In the so-called "Federation Drought" of the late 1890s, many farmers lost their entire stocks of sheep and cattle, and were forced off the land.

Some climate experts believe that this drought, too, will pass, and Australians shouldn't be too alarmed.

Bill Kinimonth, a 40-year veteran of the Bureau of Meteorology in Melbourne and now a meteorology consultant, has a very different take on the "Big Dry." Unlike environmentalists and scientists who describe the situation as a grave emergency, Kinimonth insists that the gradual warming of the earth is part of a natural cycle.

"People have been carried away with that sort of description. We are presently in what we might call the optimum period, an interglacial where earth is warmer than it has been for the last sort of 20,000 years, and I think we should be making the most of it. The alternative is not very good - a cold, dry Australia particularly, and the last glacial periods were when a lot of the central Australian desert dunes formed because of the very dry conditions then."

Man-made or natural, the drought is teaching millions of Australians some harsh lessons about the uncompromising physical nature of their country. One senior politician recently suggested that farmers move to the rain-drenched north of the country.

There's no question that climate change is a reality, he said, and "we've got to take our farms where the water is."