A high-level whistleblower has told this newspaper that America's National Oceanic and Atmospheric Administration (NOAA) breached its own rules on scientific integrity when it published the sensational but flawed report, aimed at making the maximum possible impact on world leaders including Barack Obama and David Cameron at the UN climate conference in Paris in 2015.

The report claimed that the 'pause' or 'slowdown' in global warming in the period since 1998 – revealed by UN scientists in 2013 – never existed, and that world temperatures had been rising faster than scientists expected. Launched by NOAA with a public relations fanfare, it was splashed across the world's media, and cited repeatedly by politicians and policy makers.

But the whistleblower, Dr John Bates, a top NOAA scientist with an impeccable reputation, has shown The Mail on Sunday irrefutable evidence that the paper was based on misleading, 'unverified' data.

It was never subjected to NOAA's rigorous internal evaluation process – which Dr Bates devised.

His vehement objections to the publication of the faulty data were overridden by his NOAA superiors in what he describes as a 'blatant attempt to intensify the impact' of what became known as the Pausebuster paper.