Between 20% and 40% of the world’s land area is now degraded
The world is heading towards “catastrophic” environmental breakdown that will cost trillions of dollars, claim millions of lives and destabilise economies — unless governments rapidly change course, according to the United Nations’ most comprehensive global environmental assessment to date.
The Global Environment Outlook: Seventh Edition (GEO-7), released by the UN Environment Programme (Unep) at the Environment Assembly in Nairobi, draws on the work of 287 scientists from 82 countries.
“The scientific consensus is that following current development pathways will bring catastrophic climate change, devastation to nature and biodiversity, debilitating land degradation and desertification and lingering deadly pollution — all at a huge cost to people, planet and economies,” it said.
Instead, the report argues, the world can choose a different path. That alternative requires “whole-of-society and whole-of-government approaches” to transform the systems that underpin modern life, including the economy and finance, materials and waste, energy, food and the environment.
These shifts must be supported by behavioural, social and cultural change, including respect for indigenous and local knowledge.
Despite decades of international commitments, greenhouse gas emissions have continued to rise, increasing by about 1.5% a year since 1990 and reaching a new high in 2024. As a result, global temperatures are projected to exceed 1.5°C above pre-industrial levels in the early 2030s, exceed 2°C by the 2040s, and continue to rise thereafter.
On this trajectory, climate change alone could reduce global GDP by approximately 4% by 2050 and by up to 20% by the end of the century. These estimates exclude health impacts, biodiversity loss, and climate tipping points, implying that the actual economic damage would likely be far higher.
The costs are already visible, the report noted. Climate-related extreme weather events have caused an estimated $143 billion in annual damage over the past two decades. Between 20% and 40% of the world’s land area is now degraded, affecting more than three billion people, while about 24 billion tonnes of fertile soil are lost annually.
One million of the planet’s estimated eight million species are threatened with extinction, with wildlife populations declining across most regions.
Pollution remains the largest environmental risk to human health. About nine million premature deaths each year are attributed to pollution from contaminated air, water and soils.
The economic cost of health damage from air pollution alone was estimated at $8.1 trillion in 2019 — about 6.1% of global GDP — and could rise to between $18 trillion and $25 trillion by 2060 if current trends persist.
Meanwhile, solid waste volumes, already exceeding two billion tonnes per year, are expected to nearly double by 2050, while the eight billion tonnes of plastic waste already polluting the planet continue to accumulate.
Under a business-as-usual pathway, GEO-7 warns that environmental degradation will accelerate across all fronts. Land degradation is expected to continue at current rates, with the world losing fertile and productive land equivalent to the size of Colombia or Ethiopia each year.
At the same time, climate change could reduce per-capita food availability by 3.4% by 2050. Warm-water coral reefs are expected to face near-total loss at 2°C of warming, and air pollution would continue to claim more than eight million lives annually.
Yet the report stresses that these outcomes are not inevitable. Transforming key systems through coordinated, whole-of-government and whole-of-society action could deliver global macroeconomic benefits that begin to emerge around 2050, rise to about US$20 trillion per year by 2070, and continue to grow thereafter.
Central to this transformation is moving beyond GDP as the sole measure of progress. The report calls for economic indicators that also account for human wellbeing and natural capital, helping to steer economies towards circular production systems, clean energy, sustainable agriculture and large-scale ecosystem restoration.
While the transition would require substantial upfront investment — approximately $8 trillion annually through 2050 to achieve net-zero emissions and fund biodiversity conservation — the cost of inaction would be far higher.
GEO-7 presents two broad transformation pathways. One places greater emphasis on behavioural change, including reduced material consumption and shifts in lifestyles and diets. The other relies more heavily on technological innovation and efficiency gains.
Both, the authors note, depend on deep structural change across multiple sectors and cannot succeed in isolation.
The benefits include the potential to avoid up to nine million premature deaths by 2050, mainly through reduced air pollution.
Nearly 200 million people could be lifted out of undernourishment, more than 100 million out of extreme poverty, and an additional 300 million could gain access to safely managed drinking water. Biodiversity loss would slow by 2030, natural land areas would expand and exposure to climate-related risks would decline.
Achieving this future would require sweeping reforms, including phasing out environmentally harmful subsidies, pricing pollution and resource use more accurately, accelerating circular product design, rapidly decarbonising energy systems, reforming food production and diets, and scaling up conservation and ecosystem restoration.
Addressing energy access and poverty, and ensuring social and environmental safeguards in critical mineral supply chains, are also essential.
The report points to signs of progress — including the success of the Montreal Protocol in preventing up to 0.5°C of warming by 2100, improvements in air quality in parts of Europe, North America and China, growing forest carbon uptake and the expansion of protection and conservation of terrestrial and inland waters. But these gains, it warns, remain isolated and insufficient.