Earth4All model

Overview

The Earth4All model is a system-dynamics simulation of global society and economy developed by the Club of Rome team (Sandrine Dixson-Declève, Owen Gaffney, Jayati Ghosh, Jørgen Randers, Johan Rockström, Per Espen Stoknes) as the technical backbone of “Earth for All” (2022). Building on the legacy of the original Limits to Growth model (Club of Rome, 1972), Earth4All integrates energy, food, population, inequality, and Earth-system feedbacks into a single coupled model, then explores two contrasting futures to 2100.

The model differs from its 1972 predecessor by explicitly modelling inequality at global and regional levels, including the physical dimensions of Planetary boundaries, and distinguishing between economic activity and human wellbeing — treating GDP as an inadequate proxy for social progress.

The two scenarios

Too Little Too Late (TLTL)

The baseline extrapolation. Governments and institutions continue current policies with incremental improvements but no structural transformation. Outcomes by 2050–2100:

Global average income stagnates or rises modestly, but inequality keeps growing
Several billion people remain in poverty; social frustration builds
Multiple Planetary boundaries are crossed; climate destabilisation worsens
Societies face increasing turbulence, erosion of trust, and potential collapse dynamics
The model shows this trajectory is consistent with the Limits to Growth “business as usual” overshoot-and-collapse path

Giant Leaps

A transformation scenario in which five major policy packages are implemented in the 2020s with urgency. If enacted together and quickly enough, the model projects:

Extreme poverty eliminated by 2060
Inequality reduced to 1980 levels by mid-century
Global warming limited to ~2°C with strong probability of staying below
Improved food security and land restoration
Population growth slowing sooner due to women’s empowerment and education
Human wellbeing indicators rising even as material throughput is constrained

The five packages are the Giant Leaps framework. The key insight is that timing matters: the same five leaps enacted in the 2030s produce far worse outcomes than in the 2020s, because tipping-point dynamics amplify early action.

Turnover time and system inertia

A core finding of the Earth4All model is that social and economic systems have long inertia (turnover times of 10–40 years). This means:

Policies enacted today will not fully manifest for a generation
Delay is irreversible from a trajectory standpoint — not just “slower progress” but a permanently worse attractor
The 2020s are identified as the “decisive decade” in which the fork between TLTL and Giant Leaps is still navigable

Legacy of the Limits to Growth

The 1972 Limits to Growth (Club of Rome) was among the first quantitative models to show that exponential growth on a finite planet would lead to overshoot and collapse without systemic change. The Earth4All model updates this with five decades of additional data, finds the 1972 business-as-usual projections broadly accurate, and extends the analysis with inequality, wellbeing, and tipping-point dynamics.

Resources

2026-06-05 ◦ Earth for All — Dixson-Declève et al. (Club of Rome, 2022) — describes the model architecture, two scenarios, and policy implications in detail; technical model documentation available at earth4all.life

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Earth4All

Earth for All is the Club of Rome’s 21st-century answer to The Limits to Growth (1972). Using the Earth4All model, a system-dynamics simulation integrating energy, food, population, inequality, and Earth-system feedbacks, the authors explore two futures to 2100. In “Too Little Too Late,” incremental progress fails to prevent rising inequality and ecological destabilisation. In “Giant Leaps,” five simultaneous transformational policy packages — end poverty, tackle inequality, empower women, transform food, accelerate clean energy — deliver a stable, equitable civilisation within the safe operating space defined by Planetary boundaries.

Anthropozän

“Earth for All” (Club of Rome, 2022) uses the Anthropocene framing to argue that the question for the 21st century is not whether humans are reshaping planetary systems (they are), but whether that reshaping leads to collapse or to a stable, equitable civilisation. The Earth4All model and its Giant Leaps scenario represent an attempt to answer that question with a quantitative transformation roadmap.

Doughnut Economics

“Earth for All” (Club of Rome, 2022) can be read as a quantitative, policy-operational version of doughnut economics: the Giant Leaps are five policy packages specifically designed to lift humanity above the social floor while staying below the ecological ceiling. The Earth4All model provides the system-dynamics modelling that doughnut economics lacks — quantifying which interventions are necessary and in what order.

Giant Leaps

The Giant Leaps is the transformational scenario in “Earth for All: A Survival Guide for Humanity” (Club of Rome, 2022). It consists of five interconnected policy packages that, if implemented together with urgency in the 2020s, the Earth4All model projects can stabilise climate, eliminate extreme poverty, reduce inequality, and deliver a Wellbeing economy — all within the safe operating space defined by .

Limits to Growth

“Earth for All” (Club of Rome, 2022) is the spiritual and methodological successor to Limits to Growth. The Earth4All model updates World3 with:

Planetary boundaries

In “Earth for All: A Survival Guide for Humanity” (Club of Rome, 2022), Rockström and colleagues use planetary boundaries as the biophysical ceiling for their two scenarios. The “Too Little Too Late” (TLTL) scenario sees continued boundary transgression and societal turbulence; the “Giant Leaps” scenario designs five transformational policy packages — end poverty, tackle inequality, empower women, transform food, accelerate energy — specifically to bring humanity back inside or toward the safe operating space. See Earth4All model.

Wellbeing economy

The Earth4All model (see Earth4All model) uses wellbeing indicators alongside GDP to evaluate scenarios: the Giant Leaps scenario produces markedly better wellbeing outcomes while keeping resource consumption closer to Planetary boundaries.

Earth4All model

Overview

The two scenarios

Too Little Too Late (TLTL)

Giant Leaps

Turnover time and system inertia

Legacy of the Limits to Growth

Resources

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