unsustainable

Unsustainable describes practices, systems, or trends that cannot be maintained indefinitely without causing long-term harm to ecosystems, resources, or human well-being. It contrasts with sustainability, which seeks to meet present needs without compromising the ability of future generations to meet theirs. Unsustainability can manifest when resource use exceeds natural replenishment, when pollution or waste overwhelms environmental carrying capacity, or when economic and social systems rely on inequitable or unstable foundations.

Common domains of unsustainability include energy, food, water, land, and urban systems. Examples are heavy dependence on nonrenewable fossil fuels, overfishing, deforestation, groundwater depletion, soil degradation, biodiversity loss, pollution, and waste that accumulates faster than ecosystems can absorb. Social and economic aspects—such as high inequality, chronic poverty, or fiscal practices that rely on diminishing assets—can also be unsustainable if they undermine resilience or future options.

Measurement of unsustainability often uses indicators such as ecological footprints, resource depletion rates, pollution loads, biodiversity indices, water stress, and climate indicators like carbon budgets. These metrics help compare current trajectories with planetary boundaries or long-term ecological and social resilience.

Causes of unsustainability typically include rapid population growth combined with rising per capita consumption, market failures, governance gaps, and insufficient investment in restorative technologies or institutions. Responses aim to shift toward sustainability through renewable energy, energy efficiency, circular economy principles, sustainable agriculture, improved water management, pollution controls, and policies that reflect true environmental and social costs.

Debates around the term reflect its normative aspects and context-dependent nature, with discussions about feasible paths, equity, and the pace of transition.