Feeding the city — or more accurately, feeding the 65M people in the UK, let alone the world population of 7.5bn and rising — involves a realistic look at the trade-offs we need to make.
This is why, with one slide and a couple of minutes, the last of the matters in the acronym S C A R E D is about costs.
These costs come in (at least!) two categories:
There’s some info above about the global costs of three key inputs to our food system, soil, water and energy. To bring such global matters into our minds at our personal geographic level, here are a couple of factoids, both relevant to UK agricultural production:
The Committee on Climate Change reported in 2013 that the UK top soil loss is 1-3cm per year since 1850. And that includes in the ‘breadbasket’ of the UK, East Anglia where, to anyone’s eyes, the dykes appear feet higher than they were in the early 1970s when I first visited there. Not true, the dykes aren’t higher; the land is lower as there is less of it. If top-soil loss there is 2cm a year, the land has lost 94 centimetres (over three feet) of top soil.
The only long-term viability for food security is, as said earlier, water security. All irrigation systems over time dry out. We’re lucky here in the UK, it rains a lot. Only about 2% of UK agricultural produce depends on irrigated water.
The problem is that the most fertile of arable areas, yup, East Anglia again, is in the driest part of the UK. The area is now classed as ‘semi-arid’; it’s where water is increasingly scarce.
Sure, water can be transported. But it’s heavy stuff, a mere cubic metre of water, a large, deep, bathful, weighs a tonne. Yet here in Birmingham, many of us depend on six reservoirs in and around the Elan Valley for our water supplies, gravity fed through a 88-mile, century-old feat of engineering. But where could the water come from for south east England. Kielder Water is over 300 miles away.
Arid places have an additional problem. The top soil rapidly become friable, dusty, easily blown away. And if there’s sudden rainfall, it floods easily, eroding the soil still further.
The UK Global Food Security 2017 report Environmental tipping points and food system dynamics gave two case studies, the first being ‘East Anglian Dustbowl’, the conditions for which are by no means far-fetched (pp 16-17).
The other, currently a low probability, high impact event, is a collapse in AMOC, the North Atlantic Overturning Circulation (pp 17-20). If we continue on our current carbon emission trajectory, the probability of an AMOC collapse is 50-50.
The global agri-food system has a key role in determining whether or not it happens. If it does happen, it will:
“span (at least) Europe, Central and South America, Sub-Saharan Africa, and India. Potential impacts on the global food system include a reduction in EU yields of approximately 30%, 10% of losses in rice yields in India, reduction in soya and sugar production in Latin America, and eliminating the potential to produce food in large parts of the Sahel . . . William Nordhaus has suggested that AMOC collapse could cause a 25-30% reduction in global GDP (akin to the Great Depression but permanent), but no one really knows what this figure is (Nordhaus and Boyer, 2000). Suffice to say, the prospect of an order of 10% irreversible reduction in global GDP is sufficient to radically change the outcome of cost-benefit analyses.”
Local ££-costs now
If all that appear to scary, too remote, to theoretical to think about, our food system now costs thee and me a potentially crippling amount. Most food sector profits leave the city, these costs are mostly locally borne. And they are huge:
For every £1 household food spend, £0.90 is spent on dealing with its dietary effects. The dietary effects, that is, that lead to obesity and its associated morbidities, and alcohol harm (see this blogpost for where these figures come from).
This £0.90 figure doesn’t take account of dental or mental health costs (as I couldn’t find ’em!).
Nor does it take account of the costs of recycling packaging; an extrapolation from Coca Cola’s UK sales stats indicates that Birmingham has to somehow deal with 132M cans and bottles from this company alone.