Officials from the government agency that is championing the fight against climate chaos have taken 1500 climate-wrecking flights between Scotland and England in the last year.
The Scottish Environment Protection Agency (Sepa) has been sending its staff on an average of five or six mainland air trips every working day - at the same time as urging everyone else to "fly less" to help save the planet.
The revelation has prompted a series of ferocious attacks from shocked environmental groups, who accused Sepa of being a "serial polluter". Sepa accepted that it hadn't "got the balance right".
Short-haul flights are by far the most polluting way to travel, emitting three times more carbon dioxide per passenger than trains. Every one of the 17 destinations to which Sepa's staff have flown since November 2005 is serviced by trains.
Sepa regards the climate change being caused by pollution as "the biggest environmental threat facing Scotland". The agency has recently stepped up its calls for action, warning on Friday that the country was "in danger of relying on luck" to combat the crisis.
The Sunday Herald asked Sepa, under freedom of information legislation, to provide details of every flight within mainland Britain taken by its staff on official business in the past year. Its response was a spreadsheet extending to 28 pages.
It detailed over 800 journeys, involving some 1500 individual flights. By far the most frequent trips were between Edinburgh and London, which is serviced by 20 trains a day, and can be reached in as little as four and a half hours by rail.
Sepa officials also flew often from Edinburgh and Glasgow to Birmingham, Manchester and a variety of other destinations in England and Wales.
There were also flights within Scotland, from Inverness to Edinburgh and from Aberdeen to Wick. On August 23, one Sepa employee took a return journey by air from Aberdeen to Newcastle.
The data released by Sepa also showed that its leaders sometimes chose to travel by air. Both the chairman, Sir Ken Collins, and the chief executive, Campbell Gemmell, recorded five return air trips in the last year, mostly from Glasgow or Edinburgh to London.
"These figures are shocking and Sepa's current practice is utterly unacceptable," said Dr Richard Dixon, director of WWF Scotland. Flying to London wasn't just environmental madness, he argued, it didn't even make business sense, as much more work could be done on a train.
Dixon added: "Sepa should be leading by example, instead they are doing the worst thing possible. Travel to London should be by train except in the most unusual circumstances."
Colin Howden, director of the sustainable transport campaign, TRANSform Scotland, accused Sepa of sending out contradictory messages. "Sepa is meant to be preventing pollution, not generating it," he said.
"It will be difficult to convince normal travellers to switch from air to rail when even organisations with a specific public role in tackling climate change show themselves to be doing nothing to change their travel behaviour."
Both WWF Scotland and TRANSform Scotland have strict environmental policies which permit staff to fly on business only as a last resort. None of their staff have made any journeys by air within Britain in the last year.
The internal environmental policy (pdf) of Sepa, which employs 1200 staff in 22 offices across Scotland, makes no specific mention of air travel. It just says that Sepa "will address the issue of energy use and emissions from all transport choices".
But it adds: "Sepa recognises that it occupies a unique position in respect of care for the environment and is committed to integrating high standards of environmental responsibility into all of its operations."
To guide others on how to be green, Sepa offers this advice on its website: "Fly less! Take a holiday at home, or use the channel tunnel to get to the continent - air travel produces three times more carbon dioxide per passenger than rail."
Gemmell argued Sepa had to travel to London to make sure that Scotland's voice was heard in environmental decision-making. "If our travel choices were easy, there would be no story," he told the Sunday Herald.
"We recognise that we haven't got the balance right, but we are at least striving to do so. Sepa takes its environmental impact seriously, and this is why we measure our performance and report on it openly every year."
Green MSP Mark Ruskell accepted that there might be some occasions when Sepa staff needed to fly. "But they have ratcheted up a phenomenal number of flights within the UK, undermining their message on how we must all take action to tackle climate change," he said.
"All government departments and quangos should be treating air travel as a last resort rather than a preferred means to go about their business."
This is not the first time that Sepa has been accused of making the wrong travel choices. Last month the Sunday Herald disclosed that it had billed the taxpayer for £1 million in car mileage last year, and in 2004 it came under fire for taking over 2000 flights to national and international destinations in a year.
Download a spreadsheet of Sepa's flights within mainland Britain here (100kB xls).