How many of us is too many?: Mridula Ramesh writes on the population matrix
Population and climate limit our strategic options – especially since we have doubled down on crops that do not suit our climate, pumping out so much groundwater to support them that we have altered the tilt of Earth’s axis.
Should we have more children? It’s a heavy question for a Sunday morning, but one that we must ask, in our current times.
In 2009, climate scientist Johan Rockstrom, along with 28 renowned scientists, introduced the idea of Planetary Boundaries, which serves as a kind of master health check for Earth. They defined boundaries as “safe limits for human pressure on the nine critical processes which together maintain a stable and resilient Earth”.
In 2009, we exceeded the recommended limits on at least two of these boundaries. By 2023, we had crossed these limits on six, including climate change, novel entities (microplastics, endocrine disruptors and their ilk), land-use change (think deforestation), freshwater change, biochemical flows (phosphorous and nitrogen) and biosphere integrity (we are in the midst of a sixth mass extinction; the last one being when the dinosaurs disappeared).
How much of this situation is attributable to the fact that there are “too many” of us?
According to History Database of the Global Environment (HYDE), a population land-use model, there were an estimated 19 million people on Earth 7,000 years ago, with 2.5 million living on the land that is currently India.
The database’s creator, Kees Klein Goldewijk of Utrecht University in the Netherlands, tells me this was estimated by hindcasting from later population estimates, using available literature. It was a broad stroke, not meant to be accurate at a regional level, but capable of helping us understand how land use, population and climate trade-offs might play out.
Comparing the database’s estimated carbon-dioxide concentrations at that time with CO2 concentration data from ice cores shows, if anything, that HYDE’s estimates are conservative.
This was a time when the strong Indian monsoon let rivers run full, making floodplain agriculture more productive. This likely helped India support larger populations: over the next 3,000 years, population would rise by nearly eight times, to reach 20 million.
Indeed, between 4000 and 2000 BCE, India quite possibly had the fastest growing population in the world, thanks, in part, to the agricultural marvels of the Harappan Civilisation.
These farmers mastered their local water, not by trying to control it but by shaping their cities and their diets to what the local land and climate supported. Technology, after all, is but the handmaiden of philosophy. When the philosophy was “Adapt”, water management and diets did. And so, when water was plentiful, the people gorged on wheat, but in a dry spell, they made do with foxtail millets, as archaeobotanical evidence shows.
Today, we are dazzled by shiny tech, ignoring the “winner-take-all” or “ignore-negative-externalities” philosophies operating behind many of them, and forgetting that philosophy, like climate, always comes home to roost.
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About 4,000 years ago, a study of snail shells from a lake in a Harappan-era settlement showed that the monsoon, our monsoon, weakened not for one or two years, but for two centuries. Together with other factors, this is believed to have led to the decline, or deurbanisation, of the civilisation that once flourished here.
Two millennia later, a climate shift may have played a hand in the fall of the Roman Empire. Closer to home, an interplay of climate and population appear to have shaped the many cities of Delhi, acting like a pendulum, pushing it from river to ridge and back again.
For example, Iltutmish established his city far from the Yamuna, in the defensible Lal Kot. But as the population grew, the people needed water, and so he built a tank called Hauz-i-Shamsi, in 1231. When that proved insufficient, the city began inching closer to the river.
As the Mamluks ceded to the Khiljis, a spell of weaker monsoons pushed the city closer to the river, prompting Alauddin Khilji to build another tank, Hauz Khas, to harness the rains. Even that was not enough.
As the Khiljis ceded to the Tughlaqs, the drought intensified, with famines killing thousands. “Rumours of cannibalism were current,” the historian Irfan Habib writes, in his 2001 book Economic History of Medieval India, 1200-1500.
A geological blink later, India was colonised. Between 1600 and 1700, forests turned to fields at a galloping rate. To the colonisers, driven by a philosophy of maximising revenue, this was free land. The bill for that “free” gift came due much later, as we shall see.
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In 18th-century England, the economist Thomas Malthus wrote that “the power of population is infinitely greater than the power in the earth to produce subsistence for man”.
Later in life, he taught young men headed to India as part of the East India Company that famine was a consequence of fast-growing populations. Did that particular instruction make colonial leaders less concerned with their role in famine amelioration?
The 19th century saw famines claim millions of lives. Deforestation, a fixed, cash tax, and the forest and market policies of the Raj made a dry stream flow less reliable, and pushed farmers to grow inedible or climate-unsuited crops. Did all this, paired with the export of grain while the masses starved, cause the death toll, or was it the Malthusian ogre of a growing population?
The next century saw India gain independence, after which the crude death rate (the number of deaths per 1,000 in a given year) began to plummet. It fell from 27 in 1941 to 15 in 1971, to 10 in 1991, and 7 in 2011. India, worried about its population, launched its National Family Planning Programme in 1952, the first country in the world to do so. And yet, while India’s birth rate fell, the population continued to boom.
Last year, ours became the world’s most populous country. That is not a bad thing, per se. Indeed, there are advantages to a large population: one Bengaluru is bigger than an Israel; one Delhi much larger than a Singapore. These tiny nations have spun wealth out of their vulnerabilities and so can we, if we play our cards, especially education and local policy, right.
However, per United Nations data, our numbers seem likely to swell by another 100 million by 2030 — just as the climate is changing again, asking us to make land use greener, leaving us less room to grow more crops or build on.
Where will these 100 million be housed, when our cities and towns are running out of green spaces and water bodies? Where will the land come from, to graze the animals and raise the crops they will need? Where will the cotton for their throwaway onesies be grown?
Population and climate both limit the strategic options we can take. With a smaller population and a friendlier climate, we could have taken our water for granted. Doing so now is tantamount to ritual suicide. Being blasé about food waste is a luxury we no longer have.
We may never (and I pray we never) experience famine again, but so many mouths to feed means that the smallest supply disruptions (a heatwave here or a flood there) will send prices soaring.
This is especially true since we have doubled down on crops that don’t suit their local climate, pumping out so much groundwater to support rice and sugarcane and the myriad others that we have altered the tilt of Earth’s axis.
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It’s more than food: we churn out cement, steel, cobalt, plastic, cotton and chemicals to give solidity to our ephemeral desires. The average Indian consumes only 1/10th the energy and the meat an American consumes, but the average Indian is consuming more, of late.
If that trend continues, then Houston, or rather Sriharikota, we have a problem.
It’s the defining trade-off for this generation: progeny or philosophy, somethings gotta give.
A decade ago, Samuel L Jackson, playing the eccentric villain Valentine in a Kingsman film, said: “When you get a virus, you get a fever. That’s the human body raising its core temperature to kill the virus. Planet Earth works the same way. Global warming is the fever, mankind is the virus. We’re making our planet sick. A cull is our only hope. If we don’t reduce our population ourselves, there’s only one of two ways this can go: The host kills the virus, or the virus kills the host.”
I don’t agree. There is a way for both host and “virus” to survive: we learn to co-exist. We evolve to become less lethal (as the variants of Covid-19 did), and use our resources more thoughtfully, in a philosophy that acknowledges that the environment matters.
Seeing the smog all around us, though, I wonder if that will happen fast enough.
(Mridula Ramesh is a climate-tech investor and author of The Climate Solution and Watershed. She can be reached on tradeoffs@climaction.net)