This is part of a larger project to investigate the carrying capacity of planet Earth. How many people can live on our planet in a sustainable manner, using renewable resources?
‘Carrying capacity’ is the upper limit of a population in given habitat. It is the ability of the habitat to provide the necessities of life for the population.
This is, of course, a difficult and ambiguous calculation, but it seems that the upper population limit would be several hundred billion. But even that number might be surpassed with technological innovation.
With any population level in the foreseeable future, food is not a limiting factor. Agriculture as currently practiced could provide good nutrition for many times the current population of 7 or 8 billion.
Hunger and famine, which tragically claim many human lives each year, are the results of distribution problems, not production problems. Instances of starvation or malnutrition are not due to a lack of food, but rather to a lack of delivery.
To the contrary, over the last century, production of food has exceeded the need for it. Deaths are the result of a failure to transport food to locations in which it is needed.
Slowing or stopping population growth would not reduce starvation. Even reducing the human population of the planet would not reduce starvation. Famine is the result of human nature; it is not the result of the planet’s carrying capacity.
If there were only 100 humans living on the planet, there could, and probably would, be starvation.
On the other hand, large-scale farming of seaweed would expand food supply beyond anything currently envisioned. Likewise, there is much underutilized fertile land which would expand food supply with traditional, land-based agriculture.
The earth’s mineral resources have barely been used in terms of iron and copper. The same is true of limestone for cement and concrete, and of clay for bricks.
The wise use of various energy sources will leave humans with clean air and clean water.
The works of Thomas Malthus, who wrote during the late 1700s and early 1800s, were misunderstood and misinterpreted to create a wave of concern in the 1960s and 1970s about potential ‘overpopulation.’
This misreading of Malthus led to alarmism in the popular imagination, seen in Paul Ehrlich’s The Population Bomb. Various governments formed ‘population control’ agencies and policies. Ironically, decreasing birth rates in many first-world nations led to economic misery as fewer workers had to provide for more retirees.
Declining birth rates also inhibited ‘green’ environmentally-friendly practices, as a shortage of young workers caused employers to find the most efficient practices instead of the most ‘green’ practices.
The question of our planet’s carrying capacity was not explored by the doomsayers of the 1960s and 1970s. Instead, it was simply assumed that this capacity had been reached. Paul Ehrlich’s book is filled with horrifying predictions of what would happen in the next decade or two.
Because the timeline for Ehrlich’s predictions has passed, and the disasters he predicted did not happen, researchers are carefully analyzing the question of Earth’s carrying capacity. No precise answer has been calculated, but it will be well above current population levels, and will be in the hundreds of billions.
