Losing it

Europe map according to BBC Weather Foreacst S...
Europe map according to BBC Weather Foreacst Service (Photo credit: Cea.)

This has not been a great week for the “Yes” campaign in the forthcoming Scottish independence referendum.

Rational folk might put the reason why the campaign has hit trouble is because it has tried to fudge some pretty basic economic questions about the implications of Scottish independence and has been caught out doing so.

But, it seems, some leading supporters of Scottish independence have discovered the real reason – the BBC weather forecast.

Bella Caledonia, quite a big blog in Scotland, writes this:

the BBC constantly exposes us to a more blatant misrepresentation. And the insidious nature of this visual deception is totally inappropriate in the lead-up to the independence referendum.

In fact the BBC’s weather map is based on the image of the UK as seen from geostationary weather satellites. It accurately reflects the view from space and with the Atlantic dominating the weather we get in these islands, satellite imaging, and its accurate projection is absolutely central to good forecasting.

But Bella Caledonia know better:

I’ve done a bit of 3D graphics modelling over the years, and could see that the underlying issue wasn’t obvious to those debating the perspective. I wrote to the Scotsman pointing out that the BBC was being disingenuous. When you model a virtual 3D scene you have the freedom to put the camera wherever you like, and also to choose the virtual lens. Looking down from a great height with a standard lens would result in a faithful representation of the land masses. But what the BBC’s modellers had done was to use a wide angle lens and move the virtual camera position much closer to the south of England. This has the effect of making the nearer land masses bulge larger, and those further north to taper off rapidly in perspective.

 But, of course, this is not a “virual 3D scene” at all and the idea that you can “put the camera wherever you like” misses the point: people would surely prefer more accurate weather forecasts based on this spherical projection to less accurate ones which are on Mercator’s Projection.
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6 responses to “Losing it”

  1. “people would surely prefer more accurate weather forecasts based on this spherical projection to less accurate ones which are on Mercator’s Projection.”

    That’s a non sequitur. You base your forecasts on data, not map projections. You then project your data onto a map. Any map you like. The primary purpose of the projection isn’t anything to do with accuracy, but rather readability. However, in this case, by shrinking such a large area, a heck of a lot of accuracy is lost for people in that area. A weather forecast that has two symbols covering the whole of Scotland (over 200 miles, north to south) has no informational content.

    1. Is there a weather forecast with two symbols covering the whole of Scotland? That’s sounds like just another made up grievance.
      On the projection – the second law of thermodynamics is what matters here. You cannot make your forecast more accurate by making up data – which is essentially what you are suggesting. There is no “enhance this” button in real life.

  2. Bella Caledonia may be onto something. Growing up in New York, I struggled with supposedly scientific diagrams of the solar system that showed Earth orbiting the sun, when it is well known that New York City is the center of the universe.

  3. The picture in the article is not the one to which the second quote refers. The complaint is about a view of the British Isles that focuses on the south and places Scotland in the faraway distance. Like this… http://i.dailymail.co.uk/i/pix/2009/07/15/article-0-02A68EC30000044D-749_468x344.jpg

    1. It’s a far cop. I am using the picture Zemanta gave me – which, if I were the sort of nationalist who votes for UKIP I could claim was part of the great BBC Europhile conspiracy to make the UK look small in comparison to all those lands where they speak Foreign.
      Your picture is also wrong because it is of the original projection – one that hasn’t been seen on our screens for perhaps 8 years. So we’ve both failed.

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