Forests are far more than vast stretches of green covering. They are critical sources to climate stability, biodiversity conservation and sustainable livelihoods. Yet forest climate resilience around the world is under increasing pressure due to the growing human activities.
While many people tacitly appreciate the intrinsic and aesthetic value of forests and trees, governments and policymakers struggle to take firm action to protect them, companies and environmental organizations pledges to restore them; however, the pressures from expanding road networks, forest degradation and land-use changes continue to threaten forests in many regions, through both state-sanctioned and illegal activities. The warning signs are becoming harder to ignore.
The challenge to forest climate resilience is particularly enormous between 2015 and 2025, where the world lost more than 40 million hectares of forest, including about 16 million hectares of primary forests, which are especially important for biodiversity and climate stability. And now, climate change is creating another threat: even forests that remain standing may become increasingly hot and hostile to the species living beneath their canopies.
Forest Climate Resilience: Reasons Behind The Forest Crisis
The value of forests cannot be measured only in hectares. They are also a lifeline for people, underpining efforts to reduce poverty and hunger, protect water supplies, support clean energy and provide livelihoods for well over a billion people. Yet many forest-dependent communities continue to face limited economic opportunities and weak access to markets. This makes forest conservation inseparable from human development.
A forest cannot be protected indefinitely if the people living around it have no secure alternatives to destructive land use. Successful restoration therefore needs to include local communities, Indigenous knowledge, economic opportunity and long-term stewardship.
The money gap is one of the clearest warnings concerns finance. At a time when the world needs greater collective action on environmental challenges, geopolitical tensions and short-term national interests are making international cooperation more difficult.
Development assistance fell by 23% between 2024 and 2025, the largest annual contraction on record, according to the source material. Meanwhile, private financial institutions provided US$8.9 trillion in financing to companies with high deforestation risk.
Environmentally harmful agricultural subsidies reached approximately US$406 billion annually, while finance directed toward protecting forests amounted to only about US$84 billion. The imbalance is stark.
The world already has much of the knowledge and many of the policy tools needed to protect forests. What remains urgently necessary is stronger institutions, innovative financing, political commitment and cooperation across sectors and borders.
Even standing forests are beginning to heat up
The forest crisis does not end when trees survive. Inside a healthy forest, the canopy performs a remarkable climate-control function. Leaves block sunlight, retain moisture and create cooler, more stable conditions beneath the trees.
For countless tropical species, this shaded understory is not simply comfortable habitat. It can be essential for survival. But climate change may be weakening this natural thermal shield – forest climate resilience. New research from Southeast Asia suggests that the combined effects of global warming and habitat degradation could push forest understory temperatures to unprecedented levels during the coming decades.
The implications are profound. A forest may still appear green from above while conditions beneath its canopy become increasingly dangerous for animals, plants and fungi.
Forest canopies are losing their cooling power
Previous research in Malaysian Borneo has shown that degraded forests can become more exposed to surrounding climate conditions. When logging removes portions of the canopy, more sunlight reaches the forest floor and less moisture is retained. Heat can then penetrate more deeply into the ecosystem.
Researchers wanted to understand how this thermal buffering capacity could change as global temperatures rise and development pressures continue. In a new study published in Geophysical Research Letters, researchers combined temperature measurements from 46 forest sites across Southeast Asia with satellite observations and climate-model projections. The results were unsettling.
By 2050, peak daytime temperatures inside forests could rise by an average of 1.4°C to 2.1°C, depending on the climate model used. In several areas, temperatures could exceed anything recorded in recent decades.
Under a moderate climate-mitigation pathway, more than half of Southeast Asia could experience peak understory temperatures beyond historical maximums. Under a high-emissions scenario, that area could expand to roughly two-thirds of the region.
For wildlife, a few degrees could change everything
Many tropical species already live close to their physiological heat limits. That means even seemingly modest additional warming inside forests could influence survival, reproduction, behaviour and interactions between species. Species that cannot move to cooler environments – or lack the physiological or behavioural ability to regulate their body temperatures – could be particularly vulnerable.
The threat will not be evenly distributed. Higher-altitude forests in parts of Myanmar and Laos may receive some protection from the cooling influence of elevation. Meanwhile, lowland areas of northern Cambodia, southeastern Indonesia and Borneo could face some of the strongest increases. In these areas, peak daytime temperatures could rise by as much as 4°C above baseline levels without stronger action to reduce greenhouse-gas emissions and development pressure.
A hotter forest could trigger a chain reaction
The danger extends beyond individual animals. Changing forest microclimates can affect food availability, water cycles, decomposition, nutrient cycling and the ability of forests to store carbon. Over time, these changes could weaken ecosystem resilience and reduce the services forests provide to people and nature.
This is why forest conservation cannot focus only on tree numbers. A forest is not simply a collection of trunks and leaves. It is a complex web of relationships between climate, soil, water, plants, animals and microorganisms. Destroy part of that system, and the consequences can spread far beyond the original damage.
Protecting Forest Climate Resilience
Researchers say conservation planning must increasingly account for future thermal stress. One promising approach is to identify micro-refugia — areas where temperatures are likely to remain relatively stable despite warming elsewhere.
Upland forests could become especially important because elevation may provide a natural cooling advantage. Intact forests should also receive strong protection because healthy canopies provide greater thermal buffering and may serve as climate refuges for biodiversity.
In areas expected to warm rapidly, restoring forest structure and improving connectivity between habitats could help species adapt and move toward more suitable conditions. But conservationists warn that temperature is only one piece of the puzzle. Humidity, wind, sunlight exposure and interactions within ecosystems can also determine how species respond to a changing forest climate.
The world cannot plant its way out of the forest crisis
The growing popularity of tree planting has created enormous public enthusiasm for restoring forests. But the evidence presented here points to a deeper truth. Planting trees is not the same as restoring a forest. A successful restoration project must consider biodiversity, ecosystem structure, water, soil, forest climate resilience and the needs of local communities.
And protecting existing forests is often just as important as planting new ones. A mature forest already contains complex ecological relationships that may take decades or centuries to develop. Losing it and replacing it with rows of young trees does not immediately recreate what was destroyed.
A global problem demands global cooperation
Forests were once treated primarily as domestic resources. Today, that approach is increasingly inadequate. Climate change, biodiversity loss, deforestation and forest degradation cross national borders. Smoke from wildfires travels across regions. Carbon released from forests affects the global climate. Species depend on habitats that may span several countries. International cooperation is therefore not an optional extra. It is essential.
The Global Forest Goals report shows that progress is possible, but it also demonstrates how far the world still has to go. The choice before humanity is becoming clearer. We can continue treating forests as commodities to be cleared, fragmented and exploited — while attempting to repair the damage later. Or we can recognize forests for what they truly are: living climate infrastructure, biodiversity refuges and essential foundations of human well-being.
The forest is warning us
A forest can look healthy from a distance and still be under profound stress. Its canopy may remain green. Its rivers may still flow. Birds may still call from the branches. But beneath the leaves, temperatures are rising.
The warning is not only about trees. It is about the hidden climate system that forests create for countless forms of life — and about the possibility that climate change could eventually overwhelm even nature’s own cooling mechanisms. The good news is that the future is not yet written.
Researchers have identified cooler refuges. Conservationists know that intact forests provide stronger protection. Restoration can rebuild damaged landscapes. Communities can become powerful stewards. Governments can strengthen policies. Financial institutions can redirect investment.
The tools exist. What is needed now is the political will to use them. Because saving forests is no longer simply about saving trees. It is about protecting the living systems that help make Earth habitable.
