THE Cambo field west of Shetland is a truly vast lake of hydrocarbons. It’s taken 52 years to extract around 45 billion barrels of oil and its equivalent in gas from the North Sea, and Cambo is thought to contain up to 800m barrels.

If it and 30 other planned offshore oil and gas schemes were given the green light, the transitory economic rewards would be substantial – but greater and far more long-lasting would be Scotland’s turbo-boosted contribution to melting icecaps, incinerated wildlife, flooded cities, dead coral reefs and refugee crises.

We can’t keep pumping out oil and gas. To do so would be deeply irresponsible.

So far, we haven’t even started the process of stopping, but we cannot defer any longer and the first step is saying no to extracting oil from new fields. Cambo is the test case: are the UK and Scottish governments prepared to be brave?

Now, at last, Nicola Sturgeon has budged. Though the decision on whether Cambo goes ahead is not hers – it’s up to the UK government – there has been enormous pressure on her to state her opposition. And this week, finally, she did: “I don’t think that Cambo should get the green light.”

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The First Minister has been edging towards this for months, urging Boris Johnson to “reassess” permission for drilling at Cambo in August and declaring her opposition to a policy of “maximum economic recovery” of North Sea oil in October.

Her long-awaited statement against Cambo came at Holyrood. It was an important moment. The leader of the SNP has finally accepted that even if Cambo’s oil is Scotland’s oil, and even if there would be hundreds of jobs attached to extracting it, it needs to stay in the ground.

To be clear, if drilling commenced at Cambo, extraction could still be going on years after Scotland had passed its target date to become net zero. No reasonable interpretation of the evidence on climate change allows for oil and gas to be pumped for decades into the future, as the UN and International Energy Agency have made very clear.

But that doesn’t make it easy for Ms Sturgeon, given the 64,000 well-paid jobs that exist in the oil and gas industry in the north east.

The Scottish Conservatives have reacted with haste and considerable cynicism to try and capitalise on the First Minister’s remarks, seeking to present her as selling out people’s jobs as a sop to the Scottish Greens, as if concerns about the climate crisis were just Marxist self-indulgence.

But even so, this is not quite the act of political self-sacrifice on Ms Sturgeon’s part that it might seem.

She will not be the one making the call on Cambo’s future, so in that sense, the First Minister is covered, politically. She can have a view, but is not accountable for the decision.

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She may be concerned about a Tory campaign in the local elections next spring that presents the SNP as having abandoned oil workers (unfair though that accusation would be), but she can weather that. There won’t be a UK election until at least 2023 and no Holyrood election until 2026, and the next decade will be dominated by humankind’s race to rein in rising temperatures. By 2026, supporting the development of new oil fields may seem as passé as allowing smoking in restaurants.

As for internal party politics, Ms Sturgeon has upset some of the SNP old guard, but younger members are far more likely to applaud her stance. As for an independence referendum, moderate middle ground voters – the ones who will decide a future referendum – won’t buy any economic prospectus for independence in the 2020s that puts oil at its heart.

So the political risk to Ms Sturgeon is not as great as it might seem.

The real question is how much further will she go?

The working assumption has been that the UK government will allow Cambo to go ahead. With COP26 over, experience suggests Mr Johnson will tire of being a climate champion, especially when it requires him to make difficult decisions. So if he does approve drilling, what would the First Minister do then – would she use Holyrood’s powers to prevent infrastructure supporting Cambo being built on the Scottish mainland?

That may be unlikely, but there are other things she could do. She could set a date for ending demand for oil and gas, so that industry and workers can prepare. After all, the end is inevitable: the only question is over timing.

And she must get the just transition right. The North Sea oil industry was always going to decline. No one could see what would become of oil workers after the demise of oil, until, ironically, climate change incentivised the creation of a new industry to replace it. The skills of oil workers are eminently transferable and so the renewables industry has given Aberdeen hope, but the just transition has to be well managed and well resourced.

There is one other possible trajectory here, one that is perhaps hinted at by the timing of Ms Sturgeon’s announcement. It is curious that she has finally declared against Cambo days after COP26 ended, when she could have won international plaudits for doing it during the conference.

So why now? Could it be that the Scottish Government has had wind of a plan by the UK government to come out against Cambo? The First Minister would certainly wish to avoid the impression that Boris Johnson had been bold enough to oppose the oil field when she was not. A decision against Cambo could have two potential advantages for the UK government: pushing Tory sleaze off the front pages, and allowing for other oil and perhaps coal developments quietly to be greenlighted while all the attention was on halting Cambo.

Alternatively, Ms Sturgeon made the announcement after COP26 simply because she wanted as little fanfare as possible. It would fit with her gradualist approach so far. She is also considering joining the Beyond Oil and Gas Alliance, a group of countries which have already come out against new oil and gas developments, and are working to phase-out fossil fuel extraction. This could be part of preparing the ground.

We shall see, but with Cambo, she has finally done the right thing. Now she needs to follow through.

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