The world’s 50 biggest oil companies are to pump 7m extra barrels a day over the next decade, a major new investigation has found.

Independent forecasters have calculated a dramatic uptick in output of the world’s most ubiquitous fossil fuel just as scientists urge massive cuts in carbon emissions.

Rystad Energy, a Norwegian consultancy commissioned by The Guardian newspaper, is predicting production will rise 8% between 2018 and 2030.

The United States - where President Donald Trump is refusing to sign international carbon reduction accords - will be the centre of the increase.

Americans already consume three times much carbon per capital as Scots and more than twice as much as the Chinese.

Texas alone will produce more oil than Saudi Arabia by 2030, the firm said.

Canada, where carbon emissions per capita are no better than in the US, is also expected to see more oil output.

Huge new drilling projects are expected in Argentina, Kazakhstan and in Arctic Russia.

Lorne Stockman, a senior research analyst at Oil Change International, told The Guardian, “Rather than planning an orderly decline in production, they are doubling down and acting like there is no climate crisis.

“This presents us with a simple choice: shut them down or face extreme climate disruption.”

Scientists believe the additional output will push global temperatures two-fifth of the way to a further 1.5C average rise. And that is when they predict calamitous storms and flooding.

Campaigners earlier this summer warned against proposed expansion of drilling in Scottish waters, not least west of Shetland.

Lang Banks, director of WWF Scotland, said: “Opening up even more of the North Sea and West of Shetland to oil and gas exploration is totally irresponsible and undermines other efforts to tackle the climate emergency.

“We instead need to see a just transition that enables us to harness the engineering skills currently deployed in the oil and gas industry and apply them to supporting a range of cleaner forms of energy production.

“The science is clear. To reduce the risk of dangerous global climate change, the vast majority of known fossil fuel reserves need to be left in the ground unburned.”

Ben van Beurden, the chief executive of Shell, insisted it was trying to be smart on global heating.

He said: “We believe … it is our role to make sure we make energy available with a lower carbon footprint, so that we help whether it is the aviation sector, the residential sector, the steel sector or the petrochemical sector to curtail and contain their greenhouse gas emissions.

“I believe philosophically – and I know this is a tough sell because there is a fringe that is in a different camp on this – that it is not for energy companies to curtail the use of energy.”