But the cross-Border operator’s move earned a rebuke from Scottish airline Loganair which said transport firms should focus on putting their own houses in order rather than “bashing” each other.
LNER’s campaign comes as the latest salvo against its rivals as part of a long-running battle initiated by its predecessors to persuade more air passengers to switch to trains to win more of the lucrative market between Scotland and London.
However, they are not thought to have previously attacked competitors with such bold imagery.
LNER said the relative size and weight of its train, car and aircraft sculptures reflected “the carbon emissions dumped into the atmosphere when travelling between London and Edinburgh via different modes of transport”.
It said artist Jamie Wardley had "spent over 100 hours creating the series to highlight the environmental credentials of train travel, which emits six times less emissions into the atmosphere than air travel.
“The sculptures of a car, train and plane and key landmarks in some of LNER’s most visited destinations – London, Edinburgh and Newcastle – aim to inspire and educate people on the huge impact that opting for greener modes of travel over the next year can have on the environment.”
LNER said it had used black sand “to make them as impactful as possible”.
The sand sculptures were unveiled at London King’s Cross Station on Wednesday and will be displayed at Newcastle Station from Friday and Edinburgh Waverley from Saturday.
LNER operates on the east coast main line between London and Edinburgh and on to Aberdeen, Inverness and Glasgow.
It said Britons generated an average of 949kgs of carbon a year through UK travel, comprising 554kg from flights, 290kg from car travel and 105kg from train trips.
Managing director David Horne said: “Adopting greener travel habits is something all of us can strive towards, and these sculptures are a fantastic visual representation of how the train is one of the most sustainable ways to travel, especially in relation to cars and planes.”
However, Loganair chief executive Jonathan Hinkles said the campaign was not the right approach.
He said: “The whole travel industry, not just airlines, has got a job to do around taking carbon out of the system.
"It would be more productive if every transport operator focused on how to reduce its emissions as opposed to bashing each other.
"The LNER campaign is disappointing because the rail industry still has a job to do in terms of the level of diesel rolling stock, a lot of which is of the technology where we have retired equivalent aeroplanes several decades ago.”
A spokesperson for Easyjet, which flies between Edinburgh and London, said: “This paints an entirely inaccurate picture.
"Easyjet’s emissions per passenger kilometre are around four times smaller than the factor applied by LNER.”
It said it was the only major European airline offsetting carbon emissions pending the development of zero-emission fuels.
Rivals British Airways said it was committed net zero carbon emissions by 2050, involving carbon offset, sustainable aviation fuel, hydrogen-powered aircraft and carbon capture technology.