A new study by the Optimum Population Trust (OPT) finds that the U.K. is drastically overpopulated and if everyone had to be provided for from entirely its own resources, only 17 million could be supported from a population of 60 million. I knew that the U.K. depended heavily on imported food, and during World War I, German submarine blockades threatened to starve their adversary by torpedoing British Merchant ships. At that time the population stood at just over 40 million, who were obviously very dependent on imports. I thought that now we produced around 60% of our food in total, but using modern agriculture which depends on oil and natural gas to run farm machinery and make fertilizers.
It is debatable just how much we will still be able to import in the future, as oil supplies become stretched and much more expensive - around the turn of the century, ships were powered by coal, and it might seem feasible to return to that means to drive them, although indigenous U.K. coal supplies, and how easy they will prove to extract in reality is another question. It is reasonable that we will be able to still import coal from Germany and Eastern Europe, however, for quite some years yet.
The OPT study have based their startling conclusion on the "carbon footprint" per capita, which suggests that a 70% reduction would be necessary, to maintain 60 million of us, requiring a gearing-down in the sophistication of our lives to that similar to developing nations. The number of population for the U.K. is projected to reach 65 million in a decade and to rise above 70 million by 2031, and yet even if we became carbon neutral the nation could support about 40 million at our existing quality of life. If the entire world population lived as a typical Britain, it would take three and a half planets to keep it going, which is similar to other west European nations but somewhat less than the 5 planets worth of resources if we all lived an American lifestyle.
The number of people living in the U.K. has increased by a factor of six since 1800 and by a fifth since 1950 causing relentless pressures of development on land and natural resources, and also impacts from the U.K.'s consumption of other world resources. What if anything can be done about it is another matter and certainly a political hot-potato than no political party has the temerity to address. As a mean, British parents are having less kids, down to a low of 1.63 per couple. It is suggested that couples should be encouraged to "stop at two children" and "to make greater efforts to prevent unwanted pregnancies, especially among teenagers."
London and the south-east of England are rated as being among the world's most densely populated regions, which I can believe since this is where I live. Interestingly, the U.K. is more densely populated than China - which is after all a very large area despite its own huge population. There are around 7.5 million London-dwellers, which has resulted in an increasing drive to move out into the countryside, with rural and suburban regions finding themselves under population pressure.
The OPT researchers conclude that, if there are no dramatic new forms of energy provision (which as seems likely there won't be, or not quickly enough to offset shortages of conventional energy sources such as oil and gas, which are imminent) , an environmentally sustainable U.K. population is probably under 30 million, or half of us, begging the uncomfortable question of what will happen to the other half? These conclusions are based on methods of ecological footprinting, but the underlying trouble is too many of us for the available resources, and is in fact a worldwide problem, not just for the U.K.
On the subject of resources, namely oil, I note that major oil companies such as Exxon Mobil, Shell and B.P. all reported falling production despite increasing spending on discovering and pumping the resource. The fall is thought to reflect the way increasing oil prices reduce the amount of money oil companies get back from production-sharing agreements with various governments, but also the decline in supply from ageing fields such as those under the North Sea. It is thought that the latter will cause serious difficulties in building overall production levels, particularly after 2012, which is the expected time of arrival for Peak-Oil. While there are considerable efforts being made, to develop 175 large new oil projects by 2012, it is debatable whether they will be able to offset high levels in decline from existing fields.
 "UK unable to sustain population, says study", By Joanna Corrigan. http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2008/02/18/npop118.xml
 "Top oil firms spend more but get less crude", By Alex Lawler. http://uk.reuters.com/article/companyNews/idUKL1216899220080214?symbol=BP.L