EIGHT BILLION PEOPLE ON EARTH

LITTLE NEWS AND OVERCROWDING ?

We are now eight billion humans on the planet. According to UN models, humanity crosses this milestone on Tuesday, November 15, eleven years after passing that of seven billion, on October 31, 2011.

For some, this announcement is to be welcomed as proof of the improvement in the living conditions of individuals on a planetary scale. For others, it brings its share of concerns and questions.

How far will population growth go ?

And as world leaders come together at COP27 to find solutions to climate change, will the planet be able to support and meet the needs of a growing population ?

“We are awaiting the birth of the eight billionth inhabitant of planet Earth. This event must both allow us to marvel at the progress in health, which has made it possible to extend lifespan and considerably reduce maternal and infant mortality rates, but must also sound like a reminder of our shared responsibility. to take care of our planet", summed up the UN Secretary General, Antonio Guterres, on 11 November.

Symbolic bar of 8 billion

Eight billion people on Earth. According to United Nations estimates, the world population will cross this symbolic threshold of eight billion on Tuesday, November 15, 2022.

The number has doubled in almost fifty years, compared to the four billion human beings who inhabited the planet in 1975. The curve will continue to climb in the years to come, to a peak of 10.4 billion people, which should be reached by the end of the 2080s.

A decline should then begin until the end of the century, according to the latest UN projection, entitled “World Population Outlook 2022”, released in July.

59% of the world's population now live in Asia

4.7 billion of the planet's eight billion inhabitants now live in Asia, where the two most populous countries in the world are located: China, with 1.4 billion inhabitants, and India. Note that this ranking between the two giants should be reversed by 2023.

The Asian continent represents 59% of the world's population, compared to 18% for Africa, 9% for Europe, 8% for Latin America and the Caribbean, 5% for North America and 1% for l 'Oceania.

The countries with the highest population growth are mainly in the regions of South Asia and sub-Saharan Africa.

Demographic growth is especially important in Africa – it is “ the countries of sub-Saharan Africa which should contribute to more than half of the increase projected until 2050”, according to the Department of Economic and Social Affairs of the United Nations.

Some countries stand out with very rapid changes in their birth rate. If we compare these two maps produced by the World Population Prospects, the demographic dynamics of all the continents have dropped, even if some maintain a high rate.

But others, like Kenya, are well ahead of their neighbours. Although it was already declining, in 2011 its fertility rate was still at its highest, at more than 35 births per 1,000 people. Today, its demographic transition is nearing completion:

in 40 years, Kenya thus went from 8 to 3.8 children per woman, this is what is called the demographic transition. The example of Kenya, however, retains a high average compared to Europe, for example.

European countries find their balance between 1.3 and 1.9 children per woman. However, the fertility rate in sub-Saharan Africa remains at 4.7 children per woman according to AFD.

As a result, if the demographic transition in Africa advances, in particular thanks to much lower infant mortality than before, the African population should reach 2.4 billion inhabitants in 2050, estimates INED reports. More than half of the world's population growth will then take place in Africa.

South and Southeast Asia are also experiencing significant growth, but again the dynamics are changing.

If China completed its demographic transition more than ten years ago, it is now India's turn to see its birth rate plummet. The country, with 1.3 billion inhabitants, is almost on a par with China...but in 2021 its birth rate has just fallen below the replacement level for the first time. The country should therefore decrease after a peak reached around 2070.

Conversely, there are eight countries to concentrate more than half of the world's population expected in the coming decades. These are the Democratic Republic of Congo, Egypt, Ethiopia, India, Nigeria, Pakistan, the Philippines and Tanzania.

However "most of the population growth is behind us"

According to UN projections released in July, world population is expected to peak in the 2080s and then stabilize at around 10.4 billion. “Ten billion may seem enormous, but it is ultimately a small increase if we compare it to that of the last sixty years”, affirms Gilles Pison, specialist in world demography, professor emeritus at the National Museum of Natural History and adviser with the National Institute for Demographic Studies (INED).

The symbolic bar of the first billion people on the planet had been crossed in 1800, that of two billion in 1927 then that of three billion in 1960. dizzyingly, with population growth of 2% per year. At the dawn of the 2000s, there were six billion of us on the planet, six times more than two hundred years earlier,” explains the demographer.

“Since then, the population has certainly continued to grow, but less and less quickly. Today, population growth is only 1%. And it will most certainly continue to decline. »

"The threat of a 'demographic bomb' that some feared is receding", for Gilles Pison.

“Most of the population growth is even behind us. »

But above all, once the ten billion mark has been reached, the population should stabilize and then begin to decrease slowly. For good reason, according to the UN, the fertility rate should drop from 2.3 children per woman, on average, in the world today to 2.1 in 2050. It would then stabilize at 1.8 in 2100 – the threshold that marks the end of generational renewal.

Birth control ?

Faced with this prospect, however, the question of what the planet can bear resurfaces. The anguish is not recent: from Antiquity, Plato and Aristotle worried, in their writings, about the destruction of forests and the disappearance of food sources. Later, in 1798, in his "Essay on the principle of population", Thomas Malthus was in turn alarmed by an imbalance between population and resources. But today, in the face of climate change, the fear is doubled, with both the fear that the planet will not be able to meet the needs of all the population, but also that the latter, too numerous, will end up destroying its habitat. .

“We are heading for disaster because the population is increasing much too quickly,” says Michel Sourrouille, author of the book Alerte surpopulation: le combat de demographie responsable (Édilivre editions). The 75-year-old man calls himself a Malthusian, advocating a drop in the birth rate so that population growth does not exceed that of resources.

“We cannot outlive the resources that the planet gives us”

Stabilizing the population, or even reducing it, is the solution to save the planet, thinks Michel Sourrouille: “We cannot outlive the resources that the planet gives us. It's the law of diminishing returns: the more resources we take from the Earth, the more we deplete it. In 2022, Overshoot Day – the date by which humanity has consumed all the resources the planet can regenerate in one year, calculated by the Global Footprint Network – has been set to July 28…

For many scientists, population growth is thus “one of the main factors of environmental threats”. For them, the answer is therefore simple: the human population must be reduced to alleviate the pressure on the planet. In France, the Responsible Demography association is campaigning, for example, to cap family allowances at two children. Same fight, in the United Kingdom, for the organization Population Matters.

A solution swept away by the demographer Gilles Pison. "To stop population growth suddenly, there are only three solutions: cause an increase in mortality - which no one wants -, move to another planet - which is unrealistic - or, effectively, control the birth rate" "However, this solution is just as unrealistic. It is an illusion to believe that it is enough to adopt birth control policies to see the world population drop. »

For Emmanuel Pont, engineer, more nuanced in his words and author of the book Should we stop having children to save the planet? (2022 , Payot), reducing the population is not the "priority"

Emmanuel Pont also points to the chronophagy of a birth control policy. “It takes a long time for the population to change. I had done the math, if we introduce the one-child policy in France, we will have to wait around 2100 for the population to be halved, he explains. Knowing that the objective is to achieve carbon neutrality in 2050, it will already be too late. »

Under no circumstances should authoritarian measures be imposed. An opinion shared by Emmanuel Pont: “In history, birth control policies have always gone wrong. There is a rather dark history of abuse of forced sterilizations, of eugenics finally. There is a fine line between deciding who has the right to have a child and who has the right to live… And it is also a policy that would be imposed on women, on minorities, once again. »

Stopping having children "to save the planet" also raises "philosophical questions about the right to procreation", he continues. “We're not going to put the fact of having children on the same level as consumer choices like flying or eating a steak… I find that this is a debate that quickly becomes slippery. »

24% of over 18s in some developed countries would however question their desire for a child because of the climate.

Some people have already chosen not to have children for ecological reasons. They are designated by the acronym "Gink", for Green Inclination No Kid in English, or people who claim not to want to have children to save the planet, and not to inflict on their offspring a life on a polluted Earth. and overheating.

Extremes to avoid, it seems to us.

“Changing our way of life”

Indeed for Emmanuel Pont as for Gilles Pison, the problem is less the increase in the population than our ways of living and consuming. "We must change our lifestyles, the political and economic mechanisms of society, the distribution of power and wealth between countries, the consumerist culture", details the first. “To fight against global warming, we must not be less, but we must strive, all together, for more sobriety and less consumption. “, underlines the second.

In 2015, an Oxfam report showed that countries with high birth rates – often also among the least developed – such as Pakistan (3.45), Nigeria (5.32) or Ethiopia (4. 15) represent only 3.5% of global CO2 emissions despite being home to 20% of the world's population. Conversely, the most developed countries, which have a low fertility rate, such as China (1.7), the United States (1.71) or European countries, emit 78% of CO2 while that they represent only half of humanity.

“In terms of food, for example, the planet has enough to feed ten billion people properly. Provided that he is not asked to feed them as the richest 1% eat today, with a diet that is too meaty and totally unbalanced,” continues Gilles Pison.

And this issue is all the more important since, in a few years, the maps of world demography will be completely reshuffled. India will become the most populous country and one in three people on the planet will live in Africa. “The challenge is to allow these countries to develop without becoming more aggressive for the environment. In this, the developed countries must now serve as models,” pleads the demographer.

“Furthermore, we now know that there is a correlation between improved living conditions and lower fertility. If we want to stabilize the world population, this will have to go through a reduction of inequalities, a fight against poverty, access to care and contraception everywhere in the world..."

Admittedly, but great disparities remain: in the West we are witnessing a suicidal drop in the birth rate, while in Africa an uncontrolled excess birth rate. The socio-economic and political consequences are likely to be significant.