GROWING inequality and pervasive poverty further lock countries into the cycle of higher population growth rates and increasing climate vulnerabilities. Some recent studies have inverted this proposition: without reducing social and economic inequalities, the population growth rate cannot be slowed down nor can climate vulnerabilities be reduced. Climate justice, therefore, rests on inclusion and equity in order to manage the population growth rate, demographic trends, and the sustainability of economic growth — besides achieving net zero emissions.

Dennis Meadows’ The Limits to Growth, released in 1972 by the Club of Rome, instantly became a controversial and influential book in environmentalism. Based on systems thinking, it drew attention to population and economic growth as the twin global challenges to sustainability. By integrating five elements — population, consumption of non-renewable natural resources, food production, industrialisation and pollution — the book argued that humankind was exceeding Earth’s carrying capacity. It espoused a neo-Malthusian agenda of limiting population growth and promoting sustainable economic development for life on the planet beyond 2100.

Since then, per capita GDP and population growth have remained the strongest drivers of carbon emissions. The Sixth Assessment Report of IPCC, released in 2022, has specifically identified high population growth as a “key impediment” to reaching the critical target of limiting global warming to 1.5 degrees Celsius above pre-industrial levels. Research examining the effects of different population projections on economic growth and energy use shows that reining in population growth and reducing reliance on fossil fuels can significantly decrease greenhouse gas emissions. Incorporating various population projections in climate models shows that higher population growth rates lead to higher carbon emissions.

It has been projected that slower population growth could lower emissions from 2.5 billion tons to 1.6 billion tons per year by 2050. It has also been argued that by 2100, these reductions could possibly reduce emissions by 37-41 per cent; it would also cost considerably less than the technological investments required to combat climate change.

Reducing the population growth rate alone will not solve the climate problem.

Yet, it must also be recognised that the population growth rate is only one of multiple drivers: reducing the growth rate alone will not solve the climate problem. Multiple factors contribute to climatic changes, and multiple actions are needed to address them. In other words, even if Pakistan were to become a net-zero emitter, it would not become climate-secure unless twinned with regenerating ecosystems. Population planning can help boost resilience and the effectiveness of other interventions. Above all, a robust population policy can empower people, especially women, and help improve lives that can make other actions far more effective.

Further, temperature rises will adversely impact everyone, as every additional person increases carbon emissions — albeit the rich far more than the poor. It will also increase the number of climate change victims, with the poor far exceeding the rich. A recent Oxfam study based on a survey of 125 billionaires has found that each billionaire was responsible for the annual emission of about three million metric tons of CO2; ie, over a million times the amount emitted by 90 per cent of the people. The report also estimated that 50pc-70pc of their emissions stemmed from their investments in 183 corporations, with a combined corporate equity value of $2.4 trillion. The study posits that “extreme inequality and wealth concentration undermine the ability of humanity to stop climate breakdown”.

Building on the legacy of Limits to Growth, the Club of Rome and several European think tanks have developed an intricate model, ‘Earth4All’, to explore two possible scenarios this century. These combine environmental, economic and social factors, including food production, income, taxes, energy and inequality. First, there is the ‘too little too late’ scenario that represents the current incremental changes. Second is the ‘giant leap’ scenario, indicating a global population drop to 6bn from the UN-projected 11.2bn if sustained investments are made in education and healthcare, along with transformative policy changes in food and energy security, inequality and gender equity.

With China, India and Bangladesh effectively curbing their population curves, attention is shifting towards Pakistan, a country of an estimated 487m by 2100. As Afghanistan and Pakistan are holding the world hostage on polio, Pakistan may become the ultimate road-blocker on curbing the global population growth rate.

Fifty years after Limits to Growth was printed, Pakistan has emerged as a textbook case on all five elements that were at the heart of the study. The population has increased four times from 62m in 1972 to 234m today. The rate of return on agricultural inputs has been declining, making several crops less viable. Plateauing soil productivity, loss of nutritional yield value and depletion of groundwater, forests and other resources have adversely affected the physical environment, eroded the carrying capacity of ecosystems and increased exposure to climate-induced disasters. It has also accelerated outward migration to cities, making Pakistan the most urbanised country in South Asia.

Finally, urbanisation and migration are the key drivers of Pakistan’s population dynamics and are central to discussions on climate risks, especially in the context of migration to urban and peri-urban areas. People migrate to unwelcoming and ill-prepared urban centres like Karachi, where they can only afford low-lying, flood-prone and marginal land, thus increasing their exposure to urban climate change risks. It is estimated that in Karachi, 64pc of the population lives in informal settlements.

The deficient provision of basic services weakens their capacity to adapt to climate change, resulting in victim-blaming of the poor since internally displaced migrants have a higher carbon footprint in an urban setting than they had in the rural areas before they migrated. Once in cities, their resilience level diminishes as they have fewer resources to cope with the adverse impacts of climate-induced hazards.

The ‘giant leap’ scenario of ‘Earth4All’ has lent support to voices from the Global South calling for cancellation of debt, reducing world inequality by raising carbon taxes on richer people and corporations, and decreasing hunger and poverty by respecting the carrying capacity of our ecosystems. The first step, as always, is preparing for equitable local governance.

The writer is an expert on climate change and development.

Published in Dawn, April 20th, 2023