If you got all your news from Twitter, the message today from Nicola Sturgeon on the effect of 'Brexit' on Scotland is stark, and deeply worrying.

This is how she put it on the social media site:

However, if you look at that link to which the Tweet takes you the picture is rather more nuanced - though the SNP's political opponents might use a less polite word.

Allow me to quote from the Scottish government press release to which the link leads you:

Leaving the European Union is projected to cost the Scottish economy up to £11.2 billion per year and Scottish public finances up to £3.7 billion per year. Analysis published by the Scottish Government today, drawing on research by a range of external organisations, suggests that by 2030, Scottish GDP is projected to be between £1.7 billion and £11.2 billion per year lower than it would have been if Brexit does not occur. Tax revenue is projected to be between £1.7 billion and £3.7 billion lower.

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Now that, most people will agree, is a bit different. Scotland's Gross Domestic Product could drop by between £1.7bn and £11.2bn. That's a big variation, and it's by 2030.

Similarly with the possible loss of revenue which could between £1.7bn and £3.7bn lower. Quite a large difference if you were talking about possible cuts of that order in public spending.

If you look at the government document the figures are a gathering together of estimates from various academic bodies. They are estimates of what might happen, not what will happen.

And they even include estimates from the UK Treasury - much ridiculed by Ms Sturgeon during the EU referendum for it's 'Project Fear' warnings, which she said would backfire.

Isn't this Ms Sturgeon's pre-referendum rhetoric coming back to haunt her? Well no say the Scottish government.

Scottish government sources I've spoken to say "Yes the figures do vary, we accept that but they show everyone agrees that Scotland will take a big hit if nothing is done ahead of leaving the EU."

And there's a wider argument which the SNP administration is pursuing here too.

Credit: PA

Tomorrow sees the publication of what is called GERS - Government Expenditure and Revenue Scotland.

It will show that with the decline in the north sea oil revenue there is a big multi-billion gap between what is raised in Scotland in taxes and spent by both the Scottish and UK governments.

The opposition politicians will say that the figures once again prove the benefit of Scotland being part of at least one union - the United Kingdom.

Although she did not comment on the GERS figures specifically, Ms Sturgeon today got her retaliation in first, or at least ahead of publication.

Ms Sturgeon said:

"What has changed from the last GERS publication is the context, the fact that we now face the prospect of being taken out of the EU. "What the publication today shows very clearly is that if we are removed from the EU, that challenge gets harder and the situation gets worse" >

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She added:

"So Scotland faces a choice, do we allow that situation to become harder by being taken out of the EU, or do we seek ways of protecting our EU membership so that we can continue in that context to face up to that challenge?"

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So today's publication is being seen as having two purposes. First, to fire another shot over the bows of the UK government over 'Brexit'.

Second, to try to get into context - from an SNP point of view - what most people expect to be a bad set of GERS figures tomorrow.

And it will no have escaped you that all of this is, as ever, wrapped up with the constitutional question.

Ms Sturgeon repeated today her prediction that a second indepedence referendum is "highly likely".

Her opponents say all of this - the Brexit publications, the GERS pre-buttal (political speak word) have one aim: to pave the way for that referendum.

The First Minister says she's just doing what all good governments should do - looking at the options, studying the evidence.

So what to economic experts thing of the figures?

Professor David Bell of Sterling University says there is a consensus among economists that "...BREXIT will have a negative effect on the economy for the kinds of reasons laid out in the Scottish Government paper."

But making projections as far ahead as 2030 need to be "taken with a pinch of salt".

He points out that Scotland exports around £11.6 billion worth of goods to the EU and £15.2 billion worth of goods to the rest of the world. And that Scotland's exports to the EU have been fairly static for the last decade.

And he adds that exports to the rest of the world have been growing more quickly. Total UK exports to the EU were £220 billion in 2015: Scotland’s exports to the EU are much less than its population share of UK exports.

Prof Bell then asks: "So will it have as big an impact in Scotland as the paper suggests?"

His answer: "The paper itself uses existing estimates of the effects of BREXIT for the UK as a whole and scales these down to the implications for Scotland.

"At the moment, such is the uncertainty around the nature of the BREXIT settlements over trade and migration, that any specific estimates, especially those going as far as 2030, have to be taken with a pinch of salt."