Rapid population growth has seen another billion humans added to world population in just the 11 years since 2011. In tandem with dramatic economic growth and accelerating climate change, these are placing unbearable pressures on the biosphere, foreshadowing a near future of famines, forced migration, economic collapse and endless conflict, as I outlined in the Business Post in late November.
FRITZ HABER is hardly a household name, yet the German chemist’s invention in the first decade of the 20th century arguably changed the course of human history.
His breakthrough was in creating ammonia, or chemical nitrogen. Initially, it allowed Germany to continue to produce explosives as well as fertilisers, after the British had imposed a naval blockade during World War I.
Haber also developed chlorine as a poison gas, which the German army deployed to deadly effect along the Western Front. Despite this, in 1918 he received the Nobel prize for chemistry for his invention, known as the Haber-Bosch ammonia process.
Prior to the industrial revolution, the human population had never exceeded 600 million. Having risen sharply during the 19th century, by the first decade of the 20th, it had plateaued at around 1.6 billion. The limiting factor was food production, which at the time depended heavily for fertiliser on limited supplies of animal manures and guano, a nitrogen-rich excrement from sea birds.
The Haber-Bosch process enabled the mass production of cheap agricultural fertilisers, and with it, an explosive expansion in human population far beyond what had been long understood to be the maximum carrying capacity of the planet.
Were it not for Haber’s invention, in all likelihood at least five of the eight billion people alive today would never have been born, and only a fraction of the more than 100 billion livestock in the world today could exist.
Half of all the habitable land on Earth is now used to feed our vast livestock herds, and for crop production for direct human consumption. The impacts on the biosphere have been profound.
Since the advent of human civilisation, an estimated 83 per cent of wild mammals have been lost. Some 70 per cent of all birds on Earth today are poultry and just 4 per cent of the world’s mammals are wild – humans and our livestock make up the other 96 per cent, according to a major assessment published in 2018.
Every day, around half a million babies are born worldwide. This number exceeds all the surviving great apes in the world today. “Humans are 10,000 times more common than we should be, according to the rules of the animal kingdom,” Professor Steve Jones, a British geneticist, has said.
Humanity’s evolutionary success has revolved around sequestering resources and vanquishing predators, from the largest to the microscopic, which had for millennia held our numbers in check and in balance with other species.
Our ability to exploit the almost god-like energy embedded in fossil fuels, in tandem with our creation of artificial nitrogen allowed one species, at least for a while, to slip the shackles of its evolutionary niche and rapidly establish an astonishing planetary hegemony.
Since 2011, it has taken just 11 years for the global population to increase by a billion – the equivalent of adding the entire population of Germany every year since. While the population growth rate is slowing, its sheer momentum means that, barring calamities, there will likely be close to ten billion people alive later this century.
However, one paradox that we as a species have never fully squared is that exponential growth both in human numbers and in our resource consumption is manifestly incompatible with the finite limits of a single planet.
While many countries have now reached zero population growth, or are in slight decline, the regions where growth is fastest, including sub-Saharan Africa and south-east Asia, are also among the most vulnerable to the impacts of a rapidly warming planet.
On current trends, global food production is set to drop by at least a third by 2050 as a result of climate breakdown, a senior UN official told the COP27 conference in Egypt last week. This tallies with scientific estimates of up to a billion people being forced to migrate by mid-century due to extreme temperatures, coastal inundation, famines and widespread desertification.
While the world’s poor have contributed almost nothing to the climate crisis, they are already suffering disproportionately from its impacts. There is egregious carbon inequality in the fact that the world’s richest 1 per cent account for more than twice the total emissions of the poorest four billion.
Since 1950, the global economy has grown eightfold, far outstripping population increase and lifting many out of poverty, yet the fruits of this economic El Dorado have been very unevenly distributed.
Over 250 million girls and women worldwide do not have access to contraception services and as a result, more than half of all pregnancies every year are unplanned. Strong investment in meeting this need would be a highly cost-effective and humane way of easing pressure on humanity and the natural world.
While the benefits of stabilising and beginning to reverse human population growth to ease the burgeoning global food crisis are obvious, scientific evidence on the related need to decisively shift away from livestock-based agriculture is equally clear. Today, four fifths of the world’s farmland is dedicated to livestock production, yet this creates less than a fifth of global food calories and only a third of protein.
Efforts to feed ten billion humans in a climate-altered future without destroying what remains of the natural world will be among the greatest challenges of the coming decades. Unless it is accompanied by a rapid transition towards mainly plant-based diets, our shared future may well be one of global hunger and chaos as ecosystems fail and societies collapse.