Earth's capacity Many scientists think Earth has a maximum carrying capacity of 9 billion to 10 billion people. [ How Do You Count 7 Billion People?] One such scientist, the eminent Harvard University sociobiologist Edward O. Wilson, bases his estimate on calculations of the Earth's available resources.
Recent estimates of Earth's carrying capacity run between two billion and four billion people, depending on how optimistic researchers are about international cooperation to solve collective action problems.
A trillion is a thousand billions. There are about 8 billion people now. That would be 125 times as many people as are on Earth now. Most scientists put the “carrying capacity” of Earth at around 10 billion people.
The Effects of Overpopulation
More people means an increased demand for food, water, housing, energy, healthcare, transportation, and more. And all that consumption contributes to ecological degradation, increased conflicts, and a higher risk of large-scale disasters like pandemics.
Overcrowding leads to further demand for limited resources and this, in turn, can lead to more conflict and warfare. As humans seek out more resources, they take over land that was once the habitat of other species leading to huge biodiversity loss.
Tech entrepreneur and multi-billionaire Elon Musk claims that underpopulation rather than overpopulation is the greatest threat that faces humanity, despite the current destruction of nature and the millions of people living in extreme poverty.
Earth's capacity
Many scientists think Earth has a maximum carrying capacity of 9 billion to 10 billion people. [ How Do You Count 7 Billion People?]
Yes, for two main reasons. First, people are rapidly displacing wildlife species across the globe, initiating a mass extinction event.
Our Ecological Footprint
Today, our global footprint is in overshoot. It would take 1.75 Earths to sustain our current population. If current trends continue, we will reach 3 Earths by the year 2050.
'We have been living beyond our means'
Vanessa Perez-Cirera, the global economics director at the World Resources Institute, pointed out that the world actually has the necessary resources to feed a world population of 8 billion — and potentially billions more, if we rethink our current land use practises.
The current world population of 7.6 billion is expected to reach 8.6 billion in 2030, 9.8 billion in 2050 and 11.2 billion in 2100, according to a new United Nations report being launched today.
Estimates vary, but we're expected to reach "peak human" around 2070 or 2080, at which point there will be between billion and 10.4 billion people on the planet.
No demographic data exist for more than 99% of the span of human existence. Still, with some assumptions about population size throughout human history, we can get a rough idea of this number: About 117 billion members of our species have ever been born on Earth.
The global population drop is in motion. An economist believes the diminishing birth rate will have a detrimental impact on labor supply. The reason for our impending global population shortage is attributed to falling birth rates because of increased living standards.
The world population continues to grow at an alarming rate that is breaking previous records every day. However, a new analysis claims that, in contrast to past predictions, the world's population may only reach its peak in 2050 at 9 billion people.
Together, China and India are home to more than one third of the world's population. For many decades, the size and growth of the Chinese and Indian populations have been a focus of global concerns about the rapid growth of the human population and its implications for sustainable development (United Nations, 2022c).
Geographer Chris Tucker estimates that 3 billion is a sustainable number, provided human societies rapidly deploy less harmful technologies and best management practices. Other estimates of a sustainable global population also come in at considerably less than the current population of 8 billion.
Limiting factors are resources or other factors in the environment that can lower the population growth rate. Limiting factors include a low food supply and lack of space. Competition for resources like food and space cause the growth rate to stop increasing, so the population levels off.
In response, population activists argue that overpopulation is a problem in both rich and poor countries, and arguably a worse problem in rich countries, where residents' higher per capita consumption ratchets up the impacts of their excessive numbers.
The pros of high population density include access to resources, cultural diversity, economic growth, increased demand for goods and services, and cost efficiency. The cons of high population density include limited resources, increased levels of pollution, social problems, and pressure on the natural environment.
Due to immigration, the decline in mortality rates, medical breakthroughs, and increased birth rates, populations will always increase and eventually gives rise to overpopulation.
Eventually, Earth's population could decline to between 6 and 7 billion people by the 22nd century, according to population researchers. One reason for the projected shift is the declining average number of births per woman, especially among more developed regions with more educated women.
Russia may be different. Its population is falling unusually fast and may drop to 130m by mid-century. The decline is associated with increased misery: the life expectancy at birth of Russian males plummeted from 68.8 in 2019 to 64.2 in 2021, partly because of covid, partly from alcohol-related disease.