You are an Australian or African farmer whose crops have been turned to dust by the third successive year of drought.

You are a low-altitude ski resort in the French Alps, staring at yet another winter of snowless slopes.

You are a British houseowner, whose pretty riverside home became uninsurable and lost two-thirds of its value after the authorities designated it in a zone liable to floods.

What do you do?

Well, today, you'd probably just shrug your shoulders and blame bad luck or the gods of weather. In the future, though, you may prefer to phone your attorney.

Governments, oil producers, coal-fired power plants or their corporate inheritors, even auto companies which make gas-guzzling SUVs -- all are tempting targets for climate-change lawsuits in the future, says a small but growing body of legal opinion.

"Litigation on climate-related damage is clearly on the horizon," says Richard Lord, a senior London attorney in commercial law.

He draws a parallel with lawsuits on tobacco and asbestos that were initially tossed out of court, but doggedly returned and decades later resulted in damages in the tens of billions of dollars.

But these sums would no doubt be dwarfed by any ruling that found a government or corporation deliberately promoted use of a damaging greenhouse-gas pollutant, was obstructive about cleaning it up or covered up knowledge about the threat.

"If generally accepted scientific assessments are accurate, global warming is likely to be the most expensive environmental problem ever," says Andrew Strauss, a professor of international law at Widener University Law School in Delaware and Pennsylvania.

"Determinations are going to have to be made about who is going to bear these costs... (and) litigation will very likely play a role."

Just five years ago, the idea of suing the US government, Exxon, Ford or some other big promoter or user of fossil fuels because of global warming would have raised a guffaw.

Everyone agrees with the "polluter pays" principle -- it's only fair that if someone pours sewage into a river or dumps toxic waste at sea or in the fields, he should be liable for damages.

So, by this line of thinking, if oil, gas and coal release carbon dioxide (CO2) into the atmosphere, and if CO2 traps solar heat and changes the climate system, why shouldn't those who have suffered from the damage get redress?

But, at that time, legal action seemed ludicrous.

For one thing, the available science was poor. It was unable to prove that extreme weather events were caused by the burning of fossil fuels rather than by some natural oscillation in the climate system, of the kind that the world has experienced many times in its past.

And another obstacle was how to apportion blame. If a pollutant crosses borders and is caused by a fuel willingly used by everyone, how can a specific government or corporation be held responsible for it?

Today, the blame question remains unsettled, but the scientific hurdle has shrunk significantly.

Evidence that climate change is already underway has strengthened. Research has boosted the probability link between specific bouts of extreme weather and rising greenhouse-gas emissions. And scientists are becoming more skilled at calculating how and where climate change will strike.

As a result, several volleys of lawsuits have now been fired in the United States, while in Europe, one case has been filed and several more are expected in the coming months.

These do not focus on compensation but, instead, on the first steps of establishing responsibility, corporate or political.

Twelve US states and several cities are suing the Environmental Protection Agency (EPA) over its refusal to classify greenhouse gases as pollutants under the US Clean Air Act.

In July last year, eight US states and the city of New York filed a suit against the five biggest American power companies, arguing that their CO2 emissions are a public nuisance that should be curbed.

Green groups are also suing US export credit groups for funding fossil-fuel projects abroad, a move mirrored by activists in Germany.

The United States is the biggest target in the activists' crosshairs.

It is the world's greatest source of greenhouse gases, a profligate user of fossil fuels and refuses to join the UN's Kyoto Protocol on curbing these emissions.

More usefully, from the greens' view, it also has a tradition by which successful litigation often leads to changes in government policies.

James Connaughton, chairman of the White House's Council on Environmental Quality, was asked in a recent visit to Paris whether he had given President George W. Bush any assessment of the risk to the United States from climate litigation.

"Absolutely!" said Connaughton, himself an attorney who helped sue the asbestos industry.

He added though: "Endless litigation in America typically has not solved fundamental problems... it's probably the least effective and the most expensive tool (of public policy) we have, which is why you need to get on with better economic policies, with smarter investments in technology, and creating an environment where investments in those technologies can occur."

Lord says the first batch of US lawsuits probably have a low chance of success given their novelty and the persistence of blanks in scientific knowledge.

But, he believes, their outcome could well set down vital precedents such as whether a court is competent to rule on such cases, what kinds of scientific evidence or interpretations are judicially acceptable.

The legal road ahead is very long and it may be many years before any lawsuit succeeds, but the spectre of massive liability claims is now being taken seriously, says Lord.

"If the (scientific) scenario pans out as expected in the next 20, 30 years, it will be very difficult for (CO2) emitters to say they could not have foreseen what was going to happen.

"There has been a very significant change in the oil companies' attitude, which in the past was basically to brazen it out, saying there's no such things as climate change, it's a green-extreme, politically-inspired plot," he says.

"From anecdotal evidence, it's fairly sure that the oil industry is now taking it seriously and taking legal advice."

All rights reserved. � 2005 Agence France-Presse. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by Agence France-Presse. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of Agence France-Presse.