THE Nationals have waged a relentless war against the Federal Government's emissions trading plans.

Hardly a day goes by without Nationals stalwart Senator Ron Boswell - the cheerleader for the party's anti-ETS crusade - boxing a press release in the Canberra press gallery, bagging the ETS.

The message usually boils down to this: "Introducing an ETS before the world's big polluters have made similar commitments will impose higher costs on rural exporters and destroy jobs without having any impact on the climate".

There's a "dog whistle"' too: "Do we even need an ETS when there's no clear evidence of global warming, or that it's due to CO2 pollution by humans?"

They're the same messages Senator Boswell and other Nats have also been delivering in their electorates. And the campaign appears to be working.

A recent Newspoll survey found the Coalition had jumped ahead of the Government in rural Australia. The Government's ETS was no doubt a big factor.

Another poll of Liberal MPs by The Australian also found many were opposed to leader Malcolm Turnbull's intention to negotiate changes to the ETS when it re-appears in Federal Parliament next month.

This was all too much for former Government adviser on climate change, Prof Ross Garnaut, who has largely kept out of the public eye since completing his reports last year.

He launched an attack on what he called "climate sharks" exploiting ignorance about climate change in regional areas.

These climate sceptics were "preying on the vulnerability of people not in a position to be well informed themselves".

Predictably, Senator Boswell shot out another release saying the "real sharks" were climate change "touts" in the cities who stood to earn "big bucks" from an ETS on the backs of farmers.

The Government won't worry about losing rural support, its political fortunes tied squarely to the cities. And clearly there are political pluses for the Nats in railing against the ETS.

It's the Libs who are conflicted. They hold a lot of regional seats and these MPs are nervous about an ETS. So too are some of the party's urban conservatives.

Mr Turnbull's ultimatum to quit if the party doesn't back his ETS strategy means the issue has become a political flashpoint for the Liberals.