Brexit, migration and climate pressures mean our ‘too big to fail’ global food chain could unravel

The UK’s clock has been set to Permanent Global Summer Time once more after a temporary blip. Courgettes, spinach and iceberg lettuce are back on the shelves, and the panic over the lack of imported fruit and vegetables has been contained. “As you were, everyone,” appears to be the message.

But why would supermarkets – which are said to have lost sales worth as much as £8m in January thanks to record-breaking, crop-wrecking snow and rainfall in the usually mild winter regions of Spain and Italy – be so keen to fly in substitutes from the US at exorbitant cost?

Why would they sell at a loss rather than let us go without, or put up prices to reflect the changing market? Why indeed would anyone air-freight watery lettuce across the whole of the American continent and the Atlantic when it takes 127 calories of fuel energy to fly just 1 food calorie of that lettuce to the UK from California?

The answer is that, in the past 40 years, a whole supermarket system has been built on the seductive illusion of this Permanent Global Summer Time. As a result, a cornucopia of perpetual harvest is one of the key selling points that big stores have over rival retailers. If the enticing fresh produce section placed near the front of each store to draw you in starts looking a bit empty, we might not bother to shop there at all.

But when you take into account climate change, the shortages of early 2017 look more like a taste of things to come than just a blip, and that is almost impossible for supermarkets to admit.

Add the impact of this winter’s weather on Mediterranean production, the inflationary pressures from a post-Brexit fall in the value of sterling against the euro, and the threat of tariffs as we exit the single market, and suddenly the model begins to look extraordinarily vulnerable.

Read more: The Guardian