Later today, the Trump administration is expected to announce the approval of the highly controversial Keystone XL pipeline.

The pipeline has been the subject of a major battle between environmentalists and the oil industry for years and was rejected by the Obama Administration.

We have known for a long time that Donald Trump is an oil-loving climate denier. But if you were feeling charitable and wanted to offer Trump a defence for his misinformed views, you could argue that his views were based on ignorance. Here was a busy man building a business empire who was not abreast of the facts.

He does not have that excuse any more. The man is President. He has an army of advisors. The problem for Trump is that his advisors are a subservient collection of ideologues who act as an echo chamber of climate denial.

But all Trump had to do was a quick Google this week and he would see that the climate is in trouble and that KXL will make things much worse.

Instead, Trump is set to drive us knowingly over the climate cliff. As my colleague, David Turnbull, pointed out yesterday, KXL fails the climate test.

As David noted: “Even the State Department’s own faulty review of the Keystone XL pipeline (written by a consultancy affiliated with the oil industry) showed that under a scenario in which climate change is taken seriously, the emissions associated with the Keystone XL pipeline would be the equivalent of adding 5.7 million cars to the roads each year.”

It is beyond ironic that Trump will approve the Keystone XL pipeline just days after the respected World Meteorological Organization (WMO) warned that we are moving into “truly unchartered territory” regarding climate change, with unprecedented heat levels, low ice at both poles and rising sea-levels.

2016 was the hottest year on record, with temperatures this high not seen for 115,000 years.

“Even without a strong El Niño in 2017, we are seeing other remarkable changes across the planet that are challenging the limits of our understanding of the climate system. We are now in truly uncharted territory,” said David Carlson, director of the WMO’s world climate research programme.

Prof David Reay, an emissions expert at the University of Edinburgh told the Guardian newspaper that the WMO report was “startling”, adding “The need for concerted action on climate change has never been so stark nor the stakes so high.”

Scientists were quick to criticise Trump: “While the data show an ever increasing impact of human activities on the climate system, the Trump administration and senior Republicans in Congress continue to bury their heads in the sand,” said Prof Sir Robert Watson, from the UK’s University of East Anglia and a former head of the UN climate panel.

It is worth pausing here.

The sentence from the WMO “Challenging the limits of our understanding” is deeply worrying.

To give you but one example: For a long time, scientists have been trying to understand the positive and negative feedbacks associated with climate.

Scientists have long been worried that as the Arctic melts it will release vast quantities of methane that was previously frozen in the tundra. Methane is a much more potent greenhouse gas than carbon dioxide.

As Truth-out reports this week: “A scientific study published in the prestigious journal Palaeoworld in December issued a dire — and possibly prophetic — warning, though it garnered little attention in the media. ‘Global warming triggered by the massive release of carbon dioxide may be catastrophic,’ reads the study’s abstract. ‘But the release of methane from hydrate may be apocalyptic.’

The abstract of the study adds: “The end Permian holds an important lesson for humanity regarding the issue it faces today with greenhouse gas emissions, global warming, and climate change.”

The lesson is simple – we cannot carry on drilling for oil and gas, releasing thousands of tonnes of carbon dioxide, which in turn causes the Arctic to melt leading to the release of methane which, the scientists warn may be “apocalyptic”.

Scientists are used to writing in measured language. So these types of warning are deeply worrying.

Yesterday, Vox reported on an article in Science which outlined a detailed “roadmap” for meeting the Paris climate goals of 2 degrees. As Vox said: It is so difficult and challenging, “it’s eye-opening.”

To have any faint hope of keping emissions to 2 degrees, one of the things that needs to happen is to cut emissions and fast: “Global CO2 emissions from energy and industry have to fall in half each decade. That is, in the 2020s, the world cuts emissions in half. Then we do it again in the 2030s. Then we do it again in the 2040s. It’s simple but staggering.”

The first phase, the scientists outline, over the next three years, is to “prepare for the herculean task ahead by laying vital policy groundwork.” And that means scrapping fossil fuel subsidies and new coal plants and new oil and gas infrastructure like KXL.

So if Trump approves KXL later today his is knowingly and deliberately putting us on a path above 2 degrees.

As Professor Sir Robert Watson says about Trump and his climate denying cabal: “Our children and grandchildren will look back on the climate deniers and ask how they could have sacrificed the planet for the sake of cheap fossil fuel energy”.