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Global Crisis Response

Ecological Overshoot – a case of Global Crisis (GC)

Aggravating humanity’s existential crisis by exceeding planetary boundaries

Key ideas:

1. The overshoot concept

2. The connection to throughput, complexity and overreach (human enterprises)

3. Outlining the consequences of sustained overshoot (biosphere collapse)

The Overshoot concept

“Nature is going to require reduction of human dominance over the world ecosystem. The changes this will entail are so revolutionary that we will be almost overwhelmingly tempted instead to prolong and augment our dominance at all costs” [Catton – Overshoot, 1982]

Overshoot is the concept of living beyond our planetary means; of using resources faster than they can be replenished. The 2022 global ‘Earth Overshoot Day’ was July 28th; the day when our collective demand for Earth’s resources and services exceeded the amount that could be regenerated during this same year. Individually, our ‘Ecological Footprint’ (global average of 2.9 ha/person) exceeds available productive land. In short, we are now eating into natural capital to support our current lifestyles and population. Sudhir (the founder of GCR) puts it well when he says “In economics parlance – when expense exceeds income consistently then one relies on savings, loans or some lottery-thus paving the way for debt burden for future generations. So think of healthy eco-systems, functional eco-system services as ‘savings’& ‘loans’ and fossil fuels as ‘one-time lottery’”.

All habitats have a maximum carrying capacity - the number of species that can be supported indefinitely in a given environment - which depends on the environment not becoming too degraded to support the species in question [overshoot – Catton]. Carrying capacity relates to the number of individuals as well as the manner of living. A larger number of people living lightly or a smaller number of people living large can be supported, but not both. It is a false premise that carrying capacity can be exceeded by “accepting” the environmental damage caused by too large a population with too large a set of demands; damage to the biotic and abiotic environment results in a decline in critical life-support systems resulting in an overall reduction of carrying capacity [overshoot – Catton].

Humanity has several times artificially extended carrying capacity. First, by growing at the cost of other species - using up resources which are therefore denied to other species. As a consequence, our collective biomass and that of our domesticated animals, now accounts for 97% mammalian biomass, far exceeding that of wild mammal species (3%) [Bar-on et al 2018]. Not surprisingly proportion was exactly opposite at the start of the ‘agricultural revolution’ some 10,000 years ago.

Secondly, we did so through technological innovations, from the use of fire (which made available new food types) to the Industrial revolution [Catton, overshoot]. Discovering that we could exploit fossil fuels to release massive amounts of energy was a one-off expansion of carrying capacity that cannot be repeated.

Finally, human societies exploit ‘phantom’ carrying capacity to expand beyond their own borders. When existing acreage has been used (farming, logging, fishing etc.), we went on to import or take resources from elsewhere, expanding carrying capacity through the use of “ghost acreage”. Britain and Japan for example, with small land-masses and dense populations, overcame limitations through trade, colonization and empire building, with far-reaching consequences on human societies.

There are resources we rely on for our essential needs (fresh water, food, shelter, medicines etc.) and others we use to support our way of life. These resources do not come from nowhere – we extract them from the planet – and when we have finished with them they do not disappear. This “flow of raw materials and energy from the global ecosystem’s sources ... (mines, wells, fisheries, croplands), through the economy, and back to the global ecosystem’s sinks ... (atmosphere, oceans, dumps)” [] can be termed throughput (Tp).

The 5 processes of the economy (comprising Tp) are:

● Extraction (of resources from the planet);

● Production,

● Distribution,

● Consumption (of goods);

● Excretion (of waste, pollution, heat)

We will always need essential resources to grow, maintain health, and reproduce; our shelters will always need materials; our societies will always need services and goods, but there are limits to the rates at which sources can be renewed and sinks can absorb waste.

These limits occur within planetary boundaries, which are the thresholds below which we have a “safe operating zone” [Rockstrom 2009]. Nine interlinked planetary systems have been suggested, of which at least 4 have been transgressed (climate change, biosphere integrity, land-use change and biogeochemical flows) [Rockstrom 2008, Steffen 2015]. While the planetary boundary concept exists on a global scale, an ecological footprint can be calculated for an individual person or population, measuring personal consumption of source materials and sink services [].

Sources we rely on include soil, land, water, forests, ecosystems, the seas, metals, non-metallic, minerals. Of these, many are renewable resources (those that are replenished in a human timescale), such as freshwater, which can be renewed within human lifespans. This varies geographically: in some regions water use exceeds the rate at which natural processes can replenish supply. 30% of all global freshwater passes through agricultural, industrial or urban infrastructure and this is predicted to reach 50% by 2050 [Albert et al 2020]. Soil in contrast, is a non-renewable resource and cannot be recreated within a human lifetime. When soil is lost, it is essentially gone for good. While for many of us soil is unremarkable, our societies and systems are critically dependent on the existence of healthy, fertile living soils as “the basis for food, feed, fuel and fiber production and for many critical ecosystem services” [FAO report 2015]. 75 billion tonnes of soil are estimated to be eroded annually from arable lands worldwide, while over 30% of land is “moderately to highly degraded” from erosion, salinization, compaction, acidification and chemical pollution [FAO report 2015; Borelli et al 2017].

At the other end of throughput are the sinks– including the atmosphere, oceans, lakes and rivers, seas and land – which absorb material waste, pollution and heat. Many global sinks are reaching levels beyond which they will no longer be able to accommodate our waste. The world’s oceans take up approximately 25% of the CO2 we have released; without which atmospheric CO2 levels would be far higher. Oceanic CO2 absorption has triggered alterations to pH and changes in chemical balance, which together are referred to as ocean acidification. In addition, our oceans also absorb industrial and agricultural chemical run-off, concentrated into coastal waters that many human societies depend upon. These changes in turn impact the marine ecosystem -from corals to plankton - with ongoing cascades up the oceanic food web [Doney et al 2009; 2020].

Overshoot occurs when throughput (Tp) is unsustainable and exceeds:

Replenishment rate of renewable resources (RR),

Depletion rate of non-renewable resources (NRR) and

Absorption rate and capacity of sinks

In this way economic processes are inextricably linked to the earth’s ecological processes of our planet.

Driving mechanisms for Overshoot

We are exceeding planetary boundaries and heading towards overshoot through multiple drivers, principle among which are overconsumption and increasing global population.

“The first “Warning to Humanity”... (1992), stated that developed nations are the largest polluters in the world today, and that they must greatly reduce their overconsumption to reduce pressures on resources and the global environment. Almost three decades later, high-income countries, and especially the richest sector of the population, continue to be the main consumers of natural resources and the main polluters” [Marin-Beltran et al 2021]

Overconsumption is the use of resources beyond those needed for basic needs. Economic growth has long been used as a corollary for well-being, with mass-consumption seen as the highest stage of a country’s “development”. Affluent global citizens drive resource demand through high personal consumption; as stakeholders and capitalists; and by driving societal norms, while capitalism drives companies to compete, incentivizing selling as much as possible [Wiedman et al 2021]. Status defining goods (positional goods) – cars, fridges, laptops - lock us into a race to the bottom with the pressure to keep up with ever changing status-markers. Western economic capitalist theory assumes human societies value material goods and mass consumption above all other non-material “good life goals”.

From 2000 onwards, water withdrawal increased by a factor of 6; food production by a factor of 5; fossil fuels and energy supply increased by factors of 15 and 14 respectively; metal extraction increased by a factor of 33 and non-metallic minerals by a factor of 50. [Marin Beltran et al 2021, citing the International Resource Panel]. Inefficient systems lead to wastage before consumption, while structural barriers lock in high levels of consumption through limited real choice of alternatives. Finally, substantial advertising drives continued consumption [Marin-Beltran et al 2021]. Taken together, these mechanisms drive overconsumption, even for people who are engaged and committed to pro-environmental action.

The second major driver is the size of the human population. Our capacity to reproduce far exceeds the available resource base. While the global human population is growing - predicted to reach 8.5 billion in 2030 [UN World Population Prospects 2019 report] - this growth is not geographically consistent. “Family planning, to relate population to world resources, is possible, practical and necessary. Unlike plagues of the dark ages or contemporary diseases we do not yet understand, the modern plague of overpopulation is soluble by means we have discovered and with resources we possess. What is lacking is not sufficient knowledge of the solution but universal consciousness of the gravity of the problem and education of the billions who are its victims.” - Martin Luther King [in a speech read by Coretta Scott King on his behalf, on his receipt of ‘The Planned Parenthood Federation of America – Margaret Sanger Award’,1966]

The dark mirror to excessive consumption by the world’s minority, is the continued poverty of the world’s majority [LTG]. Despite increased food production, a huge fraction of the global population are undernourished – and are underconsuming the Earth’s resources. Undernourished people account for >15% in some African countries, while obese adults reach >20% across all regions [Marin-Beltran et al 2021]. Globally there is not only overproduction and overconsumption, but also under-consumption and unequal distribution.

“On the one hand the rich look askance at our continuing poverty--on the other, they warn us against their own methods. We do not wish to impoverish the environment any further and yet we cannot for a moment forget the grim poverty of large numbers of people. Are not poverty and need the greatest polluters?” Indira Gandhi [Prime Minister of India, Speech to the UN Conference on Human Environment, Stockholm, Sweden, 14 June 1972]

The unsustainable use of resources is often driven by poverty and desperation [LTG]. Despite the real and perceived impact of poverty on natural resources, “the world’s top 10% of income earners are responsible for between 25 and 43% of environmental impact. In contrast, the world’s bottom 10% income earners exert only around 3–5% of environmental impact” [Wiedman et al 2020 citing a 2016 paper thats behind a paywall]. Many studies have now shown that wealth and income inequality are key drivers of environmental degradation and biodiversity loss [Wiedmann et al 2021, Ripple et al 2020, see Mikkelson et al 2007]

Overshoot and the Megamachine

The ‘Megamachine’, represents “the system” that operates and runs our unsustainable and exploitative modern industrial civilization, with only one goal – to increase capital. This goal must be reached “at all costs, even if it means the death of the planet.” [Fabian Scheidler]. This global “machine” is not controlled or operated, but co-opts everyone, using up people and planet to “spit out money”. High throughput results in nothing more than money, which in itself has no value. Modern science, institutions, wage-labor and states all follow this model of growth, all are interlinked and form part of this global “megamachine”.

The operation of the Megamachine is possible due to the civilizational complexity (Cc) that is characterized by extremely calibrated synchronized functioning of the key-stone hubs including critical physical infrastructures, global banking & finance, trade, grid , IT, economy of scale etc. [David Korowics, 2011]. A disturbance or failure in any one hub can create a global cascading/synchronous failure of the entire Megamachine, making our complexity based system extremely vulnerable to shocks. For example, the highly interlinked global production and distribution system, with ever longer and more complex supply chains reliant on ‘Just in Time’ (JIT) supply mechanisms, is also increasingly vulnerable to shocks, as the Covid19 pandemic has shown. A form of ghost acreage, this “overreach” drives overshoot through artificially extending a nation’s carrying capacity by exploiting global resources. Electric cars are touted as a “bright green” solution to the climate crisis, yet the devastation of lithium mining will fall disproportionately on countries and peoples other than those who will drive the bright new cars. Where systems are more complex, feedback signals are weaker or distorted. Where we (the consumer) do not directly see or feel the consequences of the ecological devastation wrought to produce our commodities, we are unaware of the warning signs. We react slowly to the cause and the effects, if we react at all.

Many people believe in technological fixes that will push back planetary boundaries – endlessly increasing carrying capacity – even as we approach them. We are continuously creating new technologies, many of which provide clean(er) energy, greater efficiency and less waste; while better reduction, reuse and recycling of materials, are all positive steps to reduce source consumption. The environmental Kuznets curve hypothesis suggests that the detrimental impact on the environment caused by the early stages of economic development will level out and decline as the economy develops; while proponents of decoupling suggest we can promote economic growth while reducing natural resource use and greenhouse gas emissions. If these theories hold, are we now reaching a plateau of resource use and emissions? Can we continue to have economic growth, without overshooting planetary boundaries?

The Jevons paradox, or rebound effect, suggests that improvements in efficiency does not drive reduction of consumption. Rather, every time technology is used to expand carrying capacity, our demands increase in pace with savings made. Consider that the extraction rates of many different metals have increased 36% since 1900 [Marin Beltran et al 2021], while the digital revolution has led to “to more consumption and inequality and remained coupled with the indirect use of energy and materials, therefore sustaining resource-intensive and greenhouse-gas growth patterns” [Wiedman et al 2021]. Technology and growth-obsessed global economy together aggravate throughput, while technology on its own generates consequences for ecological systems, from sources to sinks. Firm believers in our technological prowess will only be convinced of overshoot once the rate of collapsing systems exceeds our problem solving skills [Randers 2012].

Consequences of Overshoot

Unsustainable levels of throughput (Tp) and civilizational complexity (Cc) will push the planetary boundaries to limits beyond which Earth system processes may shift into a new state.

“Although Earth’s complex systems sometimes respond smoothly to changing pressures, it seems that this will prove to be the exception rather than the rule. Many subsystems of Earth react in a non-linear, often abrupt, way, and are particularly sensitive around threshold levels of certain key variables. If these thresholds are crossed, then important subsystems, such as a monsoon system, could shift into a new state, often with deleterious or potentially even disastrous consequences for humans” [Rockstrom et al 2009]

A radical and potentially irreversible change in a system can be called a tipping point. These tipping points may only be recognised after-the-fact, while our limited understanding of ecosystems makes it difficult to predict in advance. Examples [Club of Rome 2020 Planetary Emergency report] include:

  • exceeding 2°C warming (increase in extreme weather conditions);

  • melting of Arctic summertime sea ice (which will amplify climate change);

  • drying and die-back of boreal forests (carbon emissions);

  • Amazonian deforestation (changing rainfall patterns across the Amazon basin);

  • shifts in the West African monsoon system;

  • disruption of the Gulf Stream.

One of the least understood of earth’s systems is the biosphere, or “totality of all ecosystems (terrestrial, freshwater, and marine) on Earth and their biota” [Steffen et al 2015]. Any area has thousands of species – of plants, animals, bacteria and fungi and other organisms – that each interact and play a role in shaping the environment in which they live. This inter-reliance between organisms and their physical environment means that an impact on one species will cascade into knock-on effects on other species.

Different species have different ecosystem functions, for example as primary producers (plants) or recyclers of waste (detritivores). Ecosystems with a greater diversity of species (biodiversity) have greater resilience, as they have multiple redundancy – more than one species performing a functional role provides an insulation from losses or shocks. This theory of functional diversity (of which we still have a very limited understanding ) suggests that the less diversity there is in a system, the less stable it is. [refs - Mace]. Genetic diversity is another indicator of biosphere integrity, representing the resilience to adapt to changes in the future [steffen et al 2015]. In agriculture, for example, maintaining diverse, locally adapted and traditional varieties of our common food-plants, increases our agricultural resilience in the face of a changing climate.

Extinction rates are used as a proxy for resilience in biological communities, since we do not yet understand the complexities of biological and functional diversity [Rockstrom et al 2009]. We are now in an age of the Sixth mass extinction, an unprecedented level of extinction driven by human actions. The 5 previous mass extinctions in Earth’s history, destroyed 70-95% of all species, necessitating millions of years of recovery [Ceballos et al 2017; 2020].

“When a species disappears, a wide range of characteristics is lost forever, from genes and interactions to phenotypes and behaviors. … Every time a species or population vanishes, Earth’s capability to maintain ecosystem services is eroded” [Ceballos et al 2020]

With a loss of biodiversity comes a loss of ecosystem services [Mace et al 2014], which are the advantages to humans provided by ecosystems, such as clean water, fertile soil, pest control and climate stability. Recent declines in insects for example, have resulted in a loss of “services” of pollination and pest control, and a critical food-web link. Not only are we heading once more for a silent spring, but we are undermining our own ability to produce food. Although ecosystems can tolerate some degree of extinctions and species loss, we do not know at what trophic levels, or which types of functional groups may be “safely” lost, or which losses may trigger non-linear or even irreversible changes to our global life-support systems [Steffen 2015].

Loss of critical ecosystem services - from scarcity of resources to the failure of sinks - will lead to failures of economic infrastructure and in turn societal collapse.

“Collapse is not an attractive future. The rapid decline of population and economy to levels that can be supported by the natural systems of the globe will no doubt be accompanied by failing health, conflict, ecological devastation, and gross inequalities.”[Limits to growth]

Scarcity is already being felt in many resources. Take freshwater, which is available (per capita) at less than half 1960s levels [Marin Beltran 2021], while ⅔ of the global population already experiences severe water scarcity each year [Albert et al 2020]. Water is also a limiting factor in industrial production and agriculture, while soil loss reduces agricultural productivity, and sinks such as global oceans are already under immense pressure. Failures and collapse will begin with increased restrictions and higher prices, though these may not be noticed immediately, due to time lags between production and consumption. One way or another we will be forced to reduce resource extraction. Fishing catch for example, could be limited to a sustainable level through preemptive legislation and down-sizing of the fishing industry, or fishing communities could be wiped our because there are no more fish on which to depend [randers 2012].

Industrial nations have been increasingly shifting their ghost acreage to exploit still-existing resources, such as the move of industrial fishing boats into the waters of West Africa [80-20 Development in an Unequal World] or the illegal mining of sand [Marin Beltran 2021]. Economically powerful nations can exert leverage for favorable trade, while scarcity of key resources can lead to increased militarization and violence [see].


“Our species bloomed, and now we must expect crash (of some sort) as the natural sequel. What form our crash may take remains to be considered” [Catton, Overshoot]

Our recent ancestors “mis-constructed their good fortune” [Catton, Overshoot], believing in a limitlessness which they imagined permanent. Many years of economic growth-as-all-costs has left us with more people than ever, increasingly complex technologies demanding increasingly large amounts of energy, steady depletion of the Earth’s resources and the deterioration of many life-support systems. In addition, many of us have quality-of-life expectations that now far exceed our planetary means.

Overshoot is the logical consequence of the operation of the “Megamachine”, rather than an inconvenient side-effect (like they –it’s a design feature, not a bug). While overshoot can - and will - lead to the collapse of the current human society through exceeding planetary carrying capacity and earth system boundaries, abuse of sources and sinks could trigger the collapse in economic and globalized human networks even before we fully transgress our Earth’s ability to support us. Many experts, across many different fields of knowledge, concede that we have already entered overshoot, and must now focus on managing our decline/energy descent [Catton ‘overshoot, Jim Bendell ‘Deep Adaptation’, LTG 30 year update, Randers 2012, Siebert and Rees 2021]

“Once in unsustainable territory, human society would be forced to reduce its rate of resource use and its rate of emissions. This contraction could only happen in two ways: either through “De-growth/controlled collapse” organized by humanity, or through “un-controlled collapse” induced by nature or the market. The only thing that could not happen was for world society to remain forever in unsustainable territory, using more of nature every year than nature produces during that year.” [Randers 2012]

‘Business as usual’ (BAU) is a suicidal trajectory not just for humans but life in general. We still “have the opportunity to transform by design rather than through disaster.” [club of Rome 2020]

Global Crisis Response (GCR) was created to highlight the limitations of the mainstream environmentalism’s Risk avoidance & Mitigation strategy and lay emphasis on Risk preparedness, Risk-Management & Deep Adaptation strategies & policy responses. This approach assumes an inevitable Societal Collapse in the near term but acknowledges Biospheric Collapse as a probable event (more on this will be written in subsequent posts)

References (in approximate order of citation)

Catton, Jr, William R. (1980). Overshoot, the ecological basis of revolutionary change. Urbana: University of Illinois Press

Meadows, D. H., Randers, J., & Meadows, D. L. (2004). The limits to growth: The 30-year update.

Randers, Jorgen. (2012). The Real Message of The Limits to Growth A Plea for Forward-Looking Global Policy. GAIA - Ecological Perspectives for Science and Society. 21. 10.14512/gaia.21.2.7.

Meadows, D. H. (2015). Thinking in Systems. Chelsea Green Publishing.

Rockström, J., W. Steffen, K. Noone, Å. Persson, F. S. Chapin, III, E. Lambin, T. M. Lenton, M. Scheffer, C. Folke, H. Schellnhuber, B. Nykvist, C. A. De Wit, T. Hughes, S. van der Leeuw, H. Rodhe, S. Sörlin, P. K. Snyder, R. Costanza, U. Svedin, M. Falkenmark, L. Karlberg, R. W. Corell, V. J. Fabry, J. Hansen, B. Walker, D. Liverman, K. Richardson, P. Crutzen, and J. Foley. (2009). Planetary boundaries: exploring the safe operating space for humanity. Ecology and Society 14(2): 32.

Steffen, W., K. Richardson, J. Rockström, S.E. Cornell, 2015. Planetary boundaries: Guiding human development on a changing planet. Science 347: 736,

Wiedmann, T., Lenzen, M., Keyßer, L.T. et al. Scientists’ warning on affluence. Nat Commun 11, 3107 (2020).

Isabel Marín-Beltrán, Federico Demaria, Claudia Ofelio, Luis M. Serra, Antonio Turiel, William J. Ripple, Sharif A. Mukul, Maria Clara Costa (2021) Scientists' warning against the society of waste, Science of The Total Environment, 2021,(In Press, Corrected Proof)

Daly, Tony; Regan, Ciara and Regan Colm (eds.) (2016) 80-20: Development in an Unequal World, 7th edition, Bray: 80:20, Educating and Acting for a Better World and New Internationalist

Bar-On, Y; Phillips, R and Milo, R. 2018 The biomass distribution on Earth. PNAS 115 (25) 6506-6511;

Korowicz 2012. Trade Off: Financial System Supply-Chain Cross Contagion — A study in global systemic collapse

Albert 2020 Scientists warning to humanity on the freshwater biodiversity crisis

FAO 2015. Soil is a non-renewable resource.

Doney et al 2009

Doney et al 2020

Seibert and Rees 2021 (through the eye of a needle)

Seibert and Rees 2021 (rebuttal paper)


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