Photo by Austin Curtis on Unsplash
Population
Our world has seen astounding population growth. In the last century, the global population has increased by 6 billion people and is currently growing at more than 200,000 people a day. The UN estimates that by 2057, there will be 10 billion people living on our planet with India, China and Nigeria the most populous countries.
This isn’t just because of the amount of births, it’s also due to longer life expectancy.
In 1900, the average global life expectancy of a newborn was 32. Today it is over 73. Human lifespan has more than doubled in the space of 125 years.
The good news is that the growth in birth rate has been slowing since the 1960’s due to declining fertility rates.
The absolute number of people on earth is projected to peak towards the end of the century at 10.4 billion in 2086, and then slowly reduce to about 10.3 billion in 2100, when fertility rates drop to a below-replacement level of 1.8 children per woman.
But that’s still over 10 billion people on one planet earth.
And population impacts aren’t just about sheer numbers of people, they are driven by how much each person consumes.
Photo courtesy of United Nations
Consumption
Per capita GDP has rocketed more than tenfold in the last five decades, fuelling demand for products and services which take a further toll on natural resources. The global north has historically had the highest consumption rates, but per capita consumption is projected to rise further as developing economies flourish and mature.
We now have significantly more people on the planet, living significantly longer, and consuming significantly more. Already, earth is under pressure.
So, what if our life expectancy doubled again due to a medical breakthrough that reversed ageing, like the ReJuve? And global life expectancy moved closer to 150 in a comparatively short space of time?
Forget those UN projections about the population levelling off.
A black swan event like the ReJuve could push those numbers off the scale.
Photo courtesy of Global Footprint Network
Humans, like all animals, need a place to live and food to eat. But we are eroding our planet’s resilience by impacting key earth system processes through land use change, biodiversity loss and climate change. Humans have become a global geophysical force: and not a beneficial one. Which is why this period in Earth’s history has been called the Anthropocene.
According to the Global Footprint Network we currently need 1.75 planets to support our population.
This ecological footprint measures how fast we consume resources and generate waste, compared to how fast nature can generate those resources and absorb our waste.
By 2030 - when the global population reaches an estimated 8.5 billion people - we will need 2 planets.
This challenge is highlighted through Earth Overshoot Day: the date in a given year that humanity has used more from nature than our planet can regenerate in that same, entire year.
Earth Overshoot Day occurred on August 1 in 2024.
One of the biggest problems is the rate at which we're transforming the natural landscape through building roads and cities, and converting land to grow food. Some estimates suggest that 75% of earth’s land and 66% of the oceans have been degraded by human activity.
Food production currently uses 40% of the Earth’s habitable land and is the leading cause of habitat loss as forests and grasslands are converted to farmland. The World Resources Institute estimates an area of new farmland twice the size of India will be needed to feed the global population this century. Nearly 75% of freshwater resources are devoted to food production.
Over half of the global population lives in cities, and this is projected to double by 2050, meaning two thirds of all people will be city residents, putting immense pressure on resources. The number of megacities, defined as containing more than 10 million people, is due to grow to 43 by 2030.
It is not clear how they will sustain the populations which depend on them.
Photo by Roya Ann Miller on Unsplash
“We have no time to wait. Biodiversity loss, nature loss, it is at an unprecedented level in the history of mankind. We’re the most dangerous species in global history.”
Biodiversity loss and extinction
A direct result of these changes is that species are going extinct at a rate between 100 to 1000 times above the natural rate.
It is estimated that a million wildlife species are facing extinction, and more than one in three tree species.
WWF’s Living Planet Index shows wildlife population sizes have declined by 73% in the last 50 years, driven by habitat loss and climate change. Their report warns that we are fast approaching global tipping points such as the potential collapse of the Amazon rainforest and the rapid melting of polar ice as well as the mass die-off of coral reefs, which could create shockwaves far and wide, impacting food security and livelihoods on a global scale. Passing these tipping points, the report warns, would “pose grave threats to humanity and most species, and would damage Earth’s life-support systems and destabilise societies everywhere”. What happens in the next decade will determine the future of life on Earth.
“The health of ecosystems on which we and all other species depend is deteriorating more rapidly than ever. We are eroding the very foundations of our economies, livelihoods, food security, health and quality of life worldwide.”
Sir Robert Watson, Chair of The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services.
So what is the solution? Less people?
Maybe. That demographic transition would happen naturally, in time, given the drop in birth rate, but not before we reach 10 billion people.
But it wouldn’t if we blow up those predictions with a radical extension to life expectancy.
Less and better consumption?
We could lower our ecological footprint by making better use of what we have and reusing or reducing waste.
Better tech?
We could undoubtedly reduce impacts by moving to cleaner energy and more sustainable production systems enabled by new technologies.
This requires a reworking of financial structures with a more equitable distribution of global resources and tech to give developing economies the incentive to make those transitions.
“We rely on nature for so much – the food we eat, the air we breathe, our mental health and well-being. If we pass these tipping points, we’ll be putting our societies, our economies, and the future of our children at risk.
It’s not too late to change course – this could be a turning point instead of a tipping point. As a G7 nation, the UK must take bold action to transform our finance, energy and food systems to protect our world. ”
