Earth Is Becoming Greener. Is Nature Recovering?
Updated: Oct 9
In 2025, global vegetation greenness reached a new record. [1] The same year, catastrophic fires in Los Angeles, South Korea and Europe killed more than 90 people and forced over 300,000 evacuations, while Canada's boreal forests suffered extreme fire emissions for a third year in a row. [2]
Just because the planet is getting greener doesn’t mean it’s getting healthier or better equipped to cope with environmental challenges.
What the satellites do and don't show us
In 2016, a landmark study combined three satellite records of leaf area and found significant greening across roughly a quarter to a half of the world's vegetated land between 1982 and 2009. Less than 4% showed browning. [3] Using ten ecosystem models to test four possible drivers (CO₂, nitrogen deposition, climate change and land cover change), the researchers attributed about 70% of the greening trend to CO₂ fertilisation. [3]
Modelling does carry uncertainty, and different factors drive greening in different places. In the 2016 study, climate change was particularly important at high latitudes, while changes in land use mattered most in regions such as south-east China and the eastern United States. [3] Yet the greening trend has continued.
Despite a fall of around 6-7% in human CO₂ emissions during the pandemic, atmospheric CO₂ continued to rise in 2020 because we were still releasing more than forests, oceans and other natural sinks could absorb. [4] That year's unusually strong greening reflected a mixture of rising CO₂, warming, reforestation and temporarily favourable rainfall in the tropics. [5]
In 2025, average greenness across the world's vegetation reached a new high. Increases were observed across 68.2% of vegetated land, particularly in grasslands and croplands, [1] but it's important to note that individual years are heavily shaped by rainfall and temperature. In this particular study the 68.2% figure tells us how much vegetated land became greener that year, not what caused it.
It also tells us very little on its own about whether biodiversity or ecosystem condition is improving. What matters is knowing what's growing, why it's growing, and what kind of ecosystem belongs there. A heathland filling up with trees isn't ecological recovery, and neither is a species-rich meadow being taken over by vigorous grasses or scrub. These habitats developed under particular combinations of geology, soil fertility, hydrology, grazing and disturbance, and many of the species in them depend on the habitat remaining open.
Plants need more than carbon
Higher CO₂ concentrations around many plants can increase photosynthesis, growth and productivity. It can also improve water-use efficiency, because plants can get the carbon they need while keeping their stomata (the tiny openings in leaves) less open. [6]
But carbon is only one ingredient. In order to thrive, plants also need nutrients, water, suitable temperatures and healthy soils, while coping with competition, disease, drought and fire.
Once another resource becomes the limiting factor, extra CO₂ doesn't produce a proportional increase in growth. A plant short of nitrogen, for example, can't turn extra carbon into extra biomass, however much is available. [6]
Why not settle for a new ecological normal?
Ecosystems have always responded to changing conditions. Species move, populations expand and contract, and communities reorganise. But there are two reasons why simply leaving nature alone may not always be enough.
First, many of the landscapes we're asking to adapt aren't starting from a healthy, intact state. We've fragmented habitats, altered rivers, drained wetlands, changed soils, introduced some species and removed others, and built roads, towns and intensive farmland across routes that species might otherwise use to move.
Second, restoration doesn't have to mean recreating a landscape exactly as it looked a century ago, which in a changing climate may not even be possible.
Good restoration can repair ecological processes, reconnect habitats, restore hydrology and improve the condition and diversity of ecosystems, so that nature has more room to respond to whatever comes next. The latest international restoration standards still centre on the recovery of native ecosystems, using reference models to guide recovery while accounting for environmental change, including climate change. [7]
Sometimes the best intervention is to step back and allow natural regeneration. Sometimes active management is needed because the processes that once allowed recovery have been disrupted. The aim isn't to stop nature changing. It's to give nature a better chance of adapting.
Greening, drought and wildfire together
Behind the global picture is a constantly shifting patchwork of greening and browning. In 2024, global greenness hit what was then a new record, yet about a third of vegetated land showed browning, with hot, dry conditions causing pronounced declines in parts of southern Africa, Ukraine, the Congo rainforest and the Amazon. [8]
Yet 2025's new record for greenness coincided with severe regional wildfire disasters. However, in the satellite fire record used by the researchers, the area burned globally was the second lowest since 2002, about 16% below the long-term average. [2] Regional catastrophes and global totals can tell very different stories.
Nature is absorbing our carbon, but not reliably
The Global Carbon Budget 2025, produced by more than 130 scientists, estimates that over 2015-2024 the land sink absorbed around 21% of human CO₂ emissions and the oceans another 29%. [9] Together, that's roughly half of our emissions taken up by natural sinks instead of staying in the atmosphere. Without them, atmospheric CO₂ would be rising considerably faster. Earlier budgets put the land share higher and the ocean share lower, a reminder of how uncertain sink estimates still are.
Land and ocean sinks aren't fixed. They vary from year to year with temperature, rainfall, drought, fire and patterns such as El Niño. And there are signs that a changing climate is already making the job harder: averaged over 2015-2024, climate change and climate variability together left the land sink about 25% smaller than it would otherwise have been. [9]
The land sink in 2024 was the lowest since 2015, though preliminary estimates suggest it recovered in 2025. [9] Warming can reduce plant productivity in some regions while increasing the carbon returned to the atmosphere through ecosystem respiration. [9] In addition, decomposition and fire can release carbon stored in organic matter back into the atmosphere, meaning that even forests that grow quickly may not store that carbon permanently.
The Amazon shows how regional the picture can be. Aircraft measurements taken between 2010 and 2018 found southeastern Amazonia to be a net carbon source. The researchers linked the weakening carbon balance in the eastern Amazon to extensive forest loss and climatic changes that have made conditions hotter and seasonally drier. [10] The world can become greener while climate change and land degradation make some ecosystems less effective at absorbing carbon.
Protecting existing forests, restoring damaged woodland, allowing natural regeneration, restoring peatlands and rebuilding carbon-rich soils can all help keep carbon out of the atmosphere or increase its storage in landscapes. But we can't assume nature will keep picking up the bill.
Should we plant billions of trees?
Planting trees can be extremely valuable in the right place. Restoring native woodland, allowing natural regeneration and expanding existing forests can store carbon while providing habitat and other benefits. But planting trees on species-rich grassland, heathland or functioning peatland can damage ecosystems that are valuable precisely because they aren't woodland.
Any good restoration project should ask what landscape belongs there, how its hydrology works, which species depend on it, what its land-use history has been, and how resilient it's likely to be in the climate that's coming. The objective shouldn't be to maximise the number of leaves visible from a satellite. It should be to restore functioning ecosystems.
What the greening is telling us
Rising CO₂ has contributed to more vegetation across large parts of the planet. Forests, grasslands and other ecosystems are taking up enormous quantities of carbon. Yet the same evidence shows why simple environmental metrics can mislead.
More vegetation doesn't automatically mean more biodiversity. More photosynthesis doesn't necessarily mean more long-term carbon storage. And a physiological benefit from extra CO₂ doesn't cancel out the consequences of the warming that extra CO₂ causes.
The question isn't whether CO₂ is simply good or bad for plants. It's what happens to whole ecosystems when we change one of the fundamental ingredients life depends on while also changing temperature, rainfall and disturbance around them.
Nature can help us enormously, but it can't indefinitely compensate for ever-rising fossil-fuel emissions. Plants can help us deal with the carbon we've already put into the atmosphere. They can't give us permission to keep putting it there.
Greenness is something we can measure from space. Ecological recovery is something considerably more complicated.
References
Anniwaer, N. et al. (2026). Vegetation greenness in 2025. Nature Reviews Earth & Environment, 7, 209–212.
Jones, M.W. et al. (2026). Wildfires in 2025. Nature Reviews Earth & Environment, 7, 334–336.
Zhu, Z. et al. (2016). Greening of the Earth and its drivers. Nature Climate Change, 6, 791–795.
Blunden, J. & Boyer, T. (2021). State of the Climate in 2020. Bulletin of the American Meteorological Society, 102 (8), S1-S10.
Zhang, Y. et al. (2025). Earth's record-high greenness and its attributions in 2020. Remote Sensing of Environment, 316, 114-494.
Ainsworth, E.A. & Long, S.P. (2005). What have we learned from 15 years of free-air CO₂ enrichment (FACE)? A meta-analytic review of the responses of photosynthesis, canopy properties and plant production to rising CO₂.New Phytologist, 165, 351–372.
Gann, G.D. et al. (2026). International principles and standards for the practice of ecological restoration. Third edition. Restoration Ecology, 34, e70441.
Gui, Y. et al. (2025). Vegetation greenness in 2024. Nature Reviews Earth & Environment, 6, 255–257.
Friedlingstein, P. et al. (2026). Global Carbon Budget 2025. Earth System Science Data, 18, 3211–3288.
Gatti, L.V. et al. (2021). Amazonia as a carbon source linked to deforestation and climate change. Nature, 595, 388–393.
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