This is an extract from Dr Christopher K Tucker's book A Planet of 3 Billion:

Mapping Humanity's Long History of Ecological Destruction and Finding Our Way to a Resilient Future – A Global Citizen's Guide to Saving the Planet, in which he discusses the unspoken elements of climate change, such as ocean dead zones and population growth.

What if climate change were twice as bad as the worst projections, and still only 1/10th of the problem that humanity has foisted on our planet? What if climate change had another half that was being systematically overlooked, which in fact made it twice as bad in both scientific and lay terms? What if climate change were only one of 10 forms of “human footprint” that are undermining the ecological carrying capacity of our planet and its ability to sustainably support our species? What if all of these topics were connected to an underlying problem – the doubling of the human population since 1970? Surely we would be having a very different public debate.

Almost half a century ago, the first Earth Day, on 22 April 1970, served as a catalyst that would bring together all manner of groups concerned with a wide range of issues including offshore oil spills, pesticides like DDT, industrial polluters, toxic waste, urban sewage, habitat loss, species extinction, litter, freeway expansion, air pollution, diminished water quality, and so much more. This grab bag of environmental issues had no real internal coherence, no structure by which it could be systematically understood. Still, by the end of the year, Senator Gaylord Nelson’s efforts led to the creation of the US Environmental Protection Agency, and the passage of the Clean Air, Clean Water and Endangered Species Acts. While, to some, this success may have signalled a societal shift that would lead to the restoration of our planet, it soon became clear that this effort was at best incomplete.

The realities of climate change, which by the mid-70s had been the subject of scientific inquiry for nearly a century, finally coalesced into a clear thesis that scientists like James Hansen and Wallace “Wally” Broecker elevated in to the public discourse only in the late 1980s. The legislative action resulting from Earth Day would no doubt had taken on a very different complexion had climate change science been more mature at the time. Instead, for the next few decades, climate change was largely ignored by the American political establishment, as a potent minority in Congress, and its corporate financiers, managed to tilt the public discourse on the subject toward “teaching the debate”, rather than addressing the well-known realities of climate change head on. It has been surprisingly easy for climate deniers to distract public discourse, as the reality has been communicated in rather obtuse scientific terms such as “350 parts per million” and “2°+ Celsius” – terms that even citizens with advanced degrees can find opaque and devoid of meaning.

Alas, climate change also has another, darker half that has been systematically overlooked.

Acidification and anthropophony

While the Intergovernmental Panel on Climate Change’s recent special report on Global Warming of 1.5°C was comprehensive in its assessment of the range of symptoms, one of these symptoms, I would argue, should be elevated in the public discourse. The only reason we have not already achieved 2°+ Celsius increase is because our oceans have absorbed so much of the carbon released in to our atmosphere by modern industrialized humanity. The result has been the acidification of the oceans, which threatens all life on Earth. The oceans, specifically their phytoplankton, generate the vast majority of our planet’s oxygen budget. And the acidification going on threatens to radically disturb, if not destroy, the phytoplankton composition of our oceans.

Those who focus on sea level rise, loss of species, extreme weather patterns, increased frequency of droughts and impending water crises are all correct. However, the acidification of the oceans is such a massive threat to humanity and our planet’s larger ecological carrying capacity that it should conservatively be considered a doubling of the climate change challenge that currently haunts the popular mind. Remember, our oceans constitute 70% of our planet’s surface, and 97% of its living space. And somehow, still, humanity’s collective waste has managed to induce a toxicity in our oceans that is well on the way to the levels of ocean acidification that induced previous mass extinctions. If this is taken seriously, then future climate change projections must be considered at least twice as bad as the current public discourse allows.

Image: Unsplash

Still, climate change, as vast a challenge as it is, is only a small piece of a much bigger puzzle. It is only 1/10th of the larger human footprint that is undermining the carrying capacity of our planet.

Humanity’s centuries of industrial and consumer waste, which has been absorbed by our atmosphere and our oceans, is only the first of at least five major forms of humanity’s persistent, accumulating wastes. The second is that, due to agricultural and urban runoff, ocean dead zones are growing in number and in size, metastasizing in a way that will crush vital marine ecosystems. Thirdly, the continuous and growing industrial production and application of endocrine disruptors, heavy metals and radioactive waste are creating an accumulating global footprint of persistent toxicity. Fourth, though we are numb to it, the growing anthropophony (ie the noise generated by human technologies) has managed to disturb and undermine the basic signalling mechanisms that many animals use for mating, hunting, navigation and so many other basic biological processes. And last, we have somehow allowed five continent sized garbage gyres to accumulate, which are choking out marine life while also injecting persistent waste in to our marine food chains.

A multitude of menaces

Of course, these five forms of accumulating persistent waste are only made possible by humanity’s industrialization of the global landscape. Within this sphere lie the other five of the 10 menaces to our planet and our species.

First, for thousands of years – but with blinding expansion over the past century – humanity has extracted materials from our planet to burn and combust, whether trees, coal or oil, in the process annihilating historic wildernesses. Second, we have engaged in increasingly industrialized agriculture that has led to continuous tooling and machining of an enormous swath of the Earth’s surface, eating into historic wildernesses while also driving enormous volumes of waste byproducts in to our environment. Third, we have deployed more and more manufacturing capabilities, each with insatiable appetites for natural resources, while generating not only industrial byproducts but epic waves of post-consumer waste. Fourth, we have expanded the reach of modern infrastructure, leaving no frontier inaccessible from human development, and transecting vital ecosystems all across the planet. And, fifth, as human habitats have become increasingly urban, suburban and exurban, we have paved our planet with impermeable surfaces that have fundamentally changed how water flows, where flora can exist, how animals move and mate, and how humanity exerts itself on the remaining natural wildernesses.

Climate change is bad – twice as bad as our worst projections. But it is only a 10th of the problem that humanity has foisted on our planet and its ability to support our species. It is time that we collectively recognized that these 10 challenges facing our planet are induced by the sheer size and weight of our species, Homo sapiens, by the ecological footprint of our industrialization of Earth’s surface, and by our relentless, prolific generation of accumulating, persistent wastes. While one might blame the ecological footprint that modern individuals exert, it is time that we pay attention to and openly discuss the historically unprecedented, explosive growth of our species over just the last century.

Soon after the mid-20th century, the human population surpassed 3 billion. It was 3.7 billion by the first Earth Day in 1970. And while our concerns over the environment and climate change have waxed and waned over the subsequent half century, we have seemingly ignored the more than doubling of our human population – as though it is exogenous to all our other environmental concerns. A total of 7.5 billion came and went in 2017, with the population growing nearly 90 million more each year since then. As it turns out, population is not exogenous to our environmental concerns. Rather, runaway population growth is the main driver of climate change.

It was a rare political alignment that was achieved 49 years ago on Earth Day. But that was only a fragile consensus around some of the symptoms – certainly not the cause. Since then, many of the symptoms have worsened, and have become politically polarizing after a half a century of demonizing the proximate causes. While a palpable “population taboo” seems to silence this discussion, it is critical that that we finally get down to first principles and each ask ourselves, in the words of Joel Cohen, “How many people can the Earth support?” Any honest accounting of the ecological debt that our species has incurred will demand that we, collectively, take action immediately in order to avert catastrophe by navigating our way to a lower population plateau over the coming century.

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