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Climate change represents one of the most profound environmental challenges confronting our planet in the 21st century. While its impacts on human societies are increasingly documented, the effects on biodiversity and ecosystems are equally devastating and far-reaching. This comprehensive article examines how climate change is reshaping the natural world, threatening species survival, disrupting ecosystems, and fundamentally altering the biological fabric of our planet.
Understanding Climate Change and Its Drivers
Climate change refers to long-term shifts in global temperatures and weather patterns. While climate variability is a natural phenomenon that has occurred throughout Earth’s history, the current trajectory of climate change is unprecedented in its speed and scope, driven primarily by human activities since the Industrial Revolution.
The Science Behind Climate Change
The Earth’s climate system is warming at an alarming rate. Earth has already warmed about 1.8 F (1 C) since the Industrial Revolution. This warming is primarily caused by the accumulation of greenhouse gases in the atmosphere, which trap heat and prevent it from escaping back into space. The consequences of this warming extend far beyond rising temperatures, affecting precipitation patterns, ocean chemistry, sea levels, and the frequency and intensity of extreme weather events.
Primary Causes of Climate Change
Human activities have accelerated climate change through several key mechanisms:
- Burning fossil fuels: The combustion of coal, oil, and natural gas for energy releases massive amounts of carbon dioxide and other greenhouse gases into the atmosphere.
- Deforestation: The clearing of forests, particularly tropical rainforests, eliminates crucial carbon sinks while simultaneously releasing stored carbon.
- Industrial processes: Manufacturing, chemical production, and other industrial activities contribute significantly to greenhouse gas emissions.
- Agricultural practices: Modern agriculture, particularly livestock farming and rice cultivation, produces methane and nitrous oxide, potent greenhouse gases.
The Escalating Biodiversity Crisis
Biodiversity—the variety of life on Earth encompassing species diversity, genetic variation, and ecosystem complexity—faces unprecedented threats from climate change. The scale and speed of biodiversity loss have reached crisis levels, with implications that extend far beyond the natural world.
The Magnitude of Species Loss
The statistics surrounding biodiversity loss are staggering. Approximately 1 million species are at risk of extinction, threatening vital ecosystem services and exacerbating public health risks globally. Even more alarming, species extinctions are currently 10 to 100 times higher than the natural baseline, indicating an extinction rate that rivals historical mass extinction events.
The average abundance of native species in most major land-based habitats has fallen by at least 20% since 1900. This decline represents not just the loss of individual species, but the unraveling of complex ecological relationships that have evolved over millions of years.
Climate Change as an Emerging Dominant Threat
While land-use change has historically been the primary driver of biodiversity loss, climate change is rapidly emerging as the dominant threat. Climate change could become the main driver of biodiversity decline by the mid-21st century, according to large-scale modeling studies.
Research published in 2025 reveals a concerning milestone: climate change has been identified as the leading threat to species listed under the Endangered Species Act. This represents a fundamental shift in the threats facing imperiled species and underscores the urgency of addressing climate change.
Climate change is playing an increasingly important role in the decline of biodiversity. The impacts are already visible across the globe. Climate change has altered marine, terrestrial, and freshwater ecosystems around the world, causing the loss of local species, increased diseases, and driven mass mortality of plants and animals, resulting in the first climate-driven extinctions.
Species Extinction Risks Under Different Warming Scenarios
The relationship between global temperature rise and species extinction is not linear—it accelerates dramatically with each degree of warming. The risk of species extinction increases with every degree of warming.
Recent comprehensive research synthesizing over 450 studies provides sobering projections. If greenhouse gas emissions are managed in accordance with the Paris Agreement, nearly 1 in 50 species worldwide—an estimated 180,000 species—will be at risk of extinction by 2100, but when the climate model’s temperature is increased to a 4.9 F (2.7 C) rise, 1 in 20 species around the world would be at risk of extinction.
The IPCC has documented that the risk of species extinction increases with warming in all climate change projections, being about 10-times greater for endemic species from 1.5°C to 3°C above pre-industrial levels. Endemic species—those found nowhere else on Earth—face particularly severe risks, with ~100% on islands, ~84% on mountains, ~12% on continents and ~54% in the ocean projected to be threatened with extinction due to climate change.
Habitat Loss and Range Shifts
Climate change is fundamentally altering where species can survive. Higher temperatures have forced animals and plants to move to higher elevations or higher latitudes, many moving towards the Earth’s poles, with far-reaching consequences for ecosystems.
This geographic redistribution creates numerous challenges. Species with limited mobility, those confined to islands or mountaintops, or those with specific habitat requirements face the greatest risks. Mountain, island and freshwater ecosystems have the most at-risk species, likely because these isolated environments are surrounded by inhospitable habitats for their species, making it difficult or impossible for them to migrate and seek more favorable climates.
The IPCC has documented that half of 4000 species analyzed have shifted their distribution to higher latitudes or elevations in response to climate change. However, not all species can successfully relocate, and those that do often face new competitors, predators, or unsuitable conditions in their new ranges.
Vulnerable Species and Ecosystems
Certain taxonomic groups face disproportionate risks from climate change. Amphibians are the most threatened because amphibians’ life cycles depend heavily on weather, and are highly sensitive to shifting rainfall patterns and drought. Their permeable skin and dependence on specific moisture conditions make them particularly vulnerable to changing climatic conditions.
Freshwater species also face elevated risks. One-quarter of freshwater species are threatened with extinction, with prevalent threats including pollution, dams and water extraction, agriculture, invasive species, and overharvesting.
Trees, the foundational species of many terrestrial ecosystems, are also under severe pressure. 38% of tree species are threatened by a cocktail of threats including deforestation for urban development and agriculture, invasive alien species, and climate change.
Regional Variations in Extinction Risk
The impacts of climate change on biodiversity are not evenly distributed across the globe. Species in South America, Australia and New Zealand face the greatest threats. These regions harbor diverse species with narrow habitat ranges, limiting their ability to adapt or migrate as conditions change.
Conversely, some regions show different patterns. North America and Europe were characterized by moderate risks overall and lower Arctic risks (3 to 5%), as high-latitude species from the Arctic are generally characterized by larger range sizes and species with larger ranges are often more resilient to disturbance.
Ecosystem Collapse and Tipping Points
Beyond individual species extinctions, climate change threatens entire ecosystems with collapse—a transformation so profound that ecosystems lose their fundamental structure, function, and ability to provide essential services.
Understanding Ecosystem Collapse
Ecosystems have a certain level of resilience and can recover from human impacts with limited negative effects, but beyond a certain threshold or tipping point, sudden and radical disruption can occur, leading to ecosystem collapse.
Recent research suggests these collapses may occur faster than previously anticipated. Over a fifth of ecosystems worldwide are in danger of collapsing, and ongoing stresses and extreme events interact to accelerate rapid changes that may well be out of our control.
The Acceleration of Ecosystem Collapse
Multiple stressors acting simultaneously can trigger ecosystem collapse much sooner than single stressors alone. A “perfect storm” of continuous stress from factors such as unsustainable land use, agricultural expansion and climate change, when coupled with disruptive episodes like floods and fires, will act in concert to rapidly imperil natural systems.
Gradual climate change can be thought of as an ongoing “press”, on which the “pulse” of extreme events are now superimposed, and in combination, “presses” and “pulses” are more likely to push systems to collapse.
Examples of Ecosystem Collapse
Australia provides stark examples of climate-driven ecosystem collapse. Ecosystems across Australia have recently experienced catastrophic changes, including kelp forests shifting to seaweed turfs following a single marine heatwave in 2011, the destruction of Gondwanan refugia by wildfire in 2016, dieback of floodplain forests along the Murray River following the millennial drought in 2001–2009, large-scale conversion of alpine forest to shrubland due to repeated fires from 2003–2014, and mangrove dieback across a 1,000km stretch of the Gulf of Carpentaria after a weak monsoon in 2015-2016.
Coastal wetlands in Louisiana provide another concerning example. Coastal Louisiana’s wetlands have been endangered by a sea-level rise rate comparable to what is expected later this century, and this natural experiment indicates a 75% drowning of these wetlands by 2070 under current carbon emissions.
The Great Barrier Reef: A Case Study in Climate Impact
The Great Barrier Reef, one of Earth’s most iconic ecosystems, exemplifies the devastating impacts of climate change on marine biodiversity. This vast coral reef system, spanning 2,300 kilometers off Australia’s northeast coast, has experienced unprecedented stress in recent years.
Accelerating Bleaching Events
The frequency of mass bleaching events on the Great Barrier Reef has accelerated dramatically. The Great Barrier Reef has experienced mass coral bleaching events in 1998, 2002, 2016, 2017, 2020, 2022, and 2024, with seven events occurring in less than three decades, six of them since 2016.
Prior to these years, there is no evidence of such widespread events in the Great Barrier Reef’s 500-year coral record history, highlighting how unprecedented the current situation is.
The 2024 Mass Bleaching Event
The 2024 bleaching event marked a grim milestone. The 2024 mass coral bleaching event was the fifth mass coral bleaching event on the GBR since 2016 and had the largest spatial footprint ever recorded on the GBR, with high to extreme bleaching prevalence observed across all three regions of the GBR.
For the first time, all three sectors of the GBR are affected: south, middle, and north. The southern Great Barrier Reef, which had largely escaped previous mass bleaching events, was particularly hard hit.
The impacts were severe and widespread. Aerial surveys conducted across 1,080 reefs in March 2024 revealed bleaching affecting 74% of surveyed areas across all three regions, with some reefs experiencing severe bleaching affecting over 60% of their coral cover.
Coral Mortality and Recovery Challenges
Detailed tracking of individual coral colonies revealed the devastating progression of the 2024 event. 66 percent of the colonies were bleached by February 2024 and 80 per cent by April, and by July, 44 percent of the bleached colonies had died, with some coral genera, such as Acropora, experiencing a staggering 95 percent mortality.
In 2025, hard coral cover declined substantially across the GBR, with regional declines ranging between 14% and 30% compared to 2024 levels, with some individual reefs experiencing coral declines of up to 70.8%.
The loss of fast-growing Acropora corals is particularly concerning. Fast-growing Acropora corals, which facilitated the rapid recovery observed across many reefs between 2017 and 2024, were among the most severely impacted by the bleaching event.
The Global Context
The 2024 event formed part of the fourth global coral bleaching event, which began in February 2023 and represents the most extensive coral crisis in recorded history, with bleaching-level heat stress impacting 84% of the world’s coral reef areas across 82 countries and territories from January 2023 through March 2025.
This global scale dwarfs previous events, underscoring that coral reefs worldwide face an existential crisis from ocean warming.
The Amazon Rainforest: Approaching a Critical Tipping Point
The Amazon rainforest, often called the “lungs of the Earth,” faces an existential threat from the combined impacts of deforestation and climate change. This vast ecosystem, which has remained relatively resilient for 65 million years, may be approaching a critical tipping point.
The Tipping Point Concept
The Amazon forest system could soon reach a tipping point, inducing large-scale collapse, as the region is increasingly exposed to unprecedented stress from warming temperatures, extreme droughts, deforestation and fires, even in central and remote parts of the system.
Negative synergies between deforestation, climate change, and widespread use of fire indicate a tipping point for the Amazon system to flip to non-forest ecosystems in eastern, southern and central Amazonia at 20-25% deforestation.
Current Status and Projections
The Amazon is already showing signs of stress. 13.2% of the original Amazon forest has been lost due to deforestation and other causes, but more importantly, 30.8% of the original Amazon has been lost in the eastern third of the Amazon biome, above the speculated tipping point threshold.
This is particularly concerning because the eastern Amazon is the source of moisture that flows to the central and western regions. The loss of forest in the east could trigger cascading effects throughout the entire Amazon basin.
Looking forward, the projections are alarming. By 2050, 10% to 47% of Amazonian forests will be exposed to compounding disturbances that could push them past critical thresholds.
The Hydrological Cycle and Feedback Loops
The Amazon generates around half of its own rainfall by recycling moisture up to 6 times as air masses move from the Atlantic Ocean in the east across the basin to the west. This self-sustaining hydrological cycle is fundamental to the rainforest’s existence.
However, deforestation disrupts this cycle. The warmer the planet becomes, the drier the forest becomes; the more trees that are cut down, the drier the forest becomes and the more trees and other plants that will die, provoking more dryness; the more fires that are set to clear the land the more carbon is released into the atmosphere, increasing global warming—this is the feedback loop between climate change induced heat and deforestation, and this is how the tipping point will trigger the transformation of the Amazon rainforest into a savannah.
Early Warning Signs
Recent drying over the Amazon could be the “first warning signal” that the rainforest is approaching a tipping point, as continued deforestation could push the region past a tipping point in which a further, rapid reduction in rainfall would kill vast swathes of trees.
The first signs of more permanent drying and more severe droughts in the rainforest are already showing, with plant species adapted to wet conditions starting to die, and satellite images showing a decrease in water vapor over parts of the rainforest that are far from the arc of deforestation, with the dry season becoming lengthier and drier, with less rainfall, and 2-3° Celsius warmer.
Altered Ecosystem Functions and Services
Climate change doesn’t just threaten individual species or ecosystems—it fundamentally disrupts the essential functions and services that ecosystems provide to both wildlife and human societies.
Disruption of Essential Ecosystem Services
Ecosystems provide critical services including nutrient cycling, water purification, carbon storage, pollination, and climate regulation. Climate change is disrupting these fundamental processes in ways that cascade through entire ecological networks.
The degradation of wetlands, which filter freshwater, has led to a 35% decline in global wetland coverage since 1970, increasing waterborne diseases and reducing water availability for over 2 billion people.
The complex interactions between species and their environments drive the functioning of ecosystems, providing essential services like clean air, water, pollination, and climate regulation. When climate change disrupts these interactions, the consequences extend far beyond the natural world.
Carbon Cycle Disruption
The Earth’s land and the ocean serve as natural carbon sinks, absorbing large amounts of greenhouse gas emissions, and conserving and restoring natural spaces, and the biodiversity they contain, is essential for limiting emissions and adapting to climate impacts.
However, as ecosystems degrade or collapse, they can shift from carbon sinks to carbon sources, creating a dangerous positive feedback loop that accelerates climate change. Amazonian forest dieback would prevent primary and secondary forests from removing almost 1 billion tonnes of CO² per year and recycling up to 50% rainfall, making the region a permanent carbon source.
Invasive Species and Altered Community Dynamics
Climate change creates opportunities for invasive species to establish and spread, often at the expense of native species. Changing temperature and precipitation patterns can make previously inhospitable areas suitable for invasive species, while simultaneously stressing native species that are adapted to historical climate conditions.
These invasive species can outcompete native species for resources, introduce new diseases, alter habitat structure, and fundamentally change ecosystem dynamics. The result is often decreased biodiversity and altered ecosystem functions that can persist for decades or longer.
Synergistic Threats: Climate Change and Other Stressors
Climate change rarely acts alone. Its impacts are amplified when combined with other human-driven stressors, creating synergistic effects that are more severe than the sum of individual threats.
The Five Major Drivers of Biodiversity Loss
The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) has identified five major drivers of biodiversity loss: climate change, invasive species, land and sea use change, pollution, and overexploitation.
While the main driver of biodiversity loss remains humans’ use of land—primarily for food production, with human activity having already altered over 70 per cent of all ice-free land, the relative importance of these drivers is shifting.
While land-use change has historically been a significant factor, climate change could overtake it as the primary driver of biodiversity loss by mid-century.
Compounding Effects
When the interaction between projected climate change and habitat loss is taken into account, the extinction risk of birds and mammals in 15–32% of terrestrial biodiversity hotspots changes, demonstrating how multiple stressors interact in complex ways.
The impacts of land-use change and climate change combined result in biodiversity loss in all world regions, with no region escaping the combined effects of these threats.
Marine Pollution and Climate Change
Marine pollution has increased tenfold since 1980, affecting at least 267 species, including 86% of marine turtles, 44% of seabirds, and 43% of marine mammals. When combined with ocean warming, acidification, and deoxygenation driven by climate change, these stressors create conditions that many marine species cannot survive.
Regional Impacts and Biodiversity Hotspots
Climate change impacts vary significantly across different regions and ecosystems, with some areas facing particularly severe threats.
The Arctic: Warming at Unprecedented Rates
In the Arctic, climate change is the primary driver of biodiversity loss, exacerbating other environmental pressures in this already fragile region, as the Arctic is warming four times faster than the rest of the planet, leading to unprecedented temperature increases, rapid loss of summer sea ice, and ocean acidification.
Summer Arctic sea ice is shrinking by 13 per cent per decade, and if global temperatures rise beyond 1.5°C, the Arctic will most likely lose its summer sea ice by 2050, destroying critical habitats for species like polar bears.
Island Ecosystems
Islands are particularly vulnerable to climate change impacts. Despite covering approximately 2% of the Earth’s land area, islands harbour more than 20% of extant terrestrial species, with disproportionately higher rates of endemism and threat when compared to continents, with 80% of historical extinctions having occurred on islands.
Current climate change projections suggest that insular species are particularly sensitive and, even at mild warming levels, substantial losses are expected.
Freshwater Ecosystems
Freshwater ecosystems face multiple climate-related threats including altered precipitation patterns, increased temperatures, changes in water chemistry, and more frequent extreme events like droughts and floods. Current extinction rates of river fish species may be 7% greater due to climate change, with the main threat coming from drought and reduced river flows.
The Human Dimension: Biodiversity Loss and Society
The loss of biodiversity and ecosystem collapse have profound implications for human societies, affecting everything from food security to economic stability and public health.
Economic Dependencies on Nature
Over half of global GDP is dependent on nature, more than 1 billion people rely on forests for their livelihoods, and land and the ocean absorb more than half of all carbon emissions. The degradation of natural systems therefore represents not just an environmental crisis, but an economic one as well.
Food Security and Agriculture
Biodiversity supports key ecosystem services like soil fertility, natural pest control, pollination and water regulation, all of which are essential for agriculture and food production. The loss of pollinators alone could have devastating consequences for global food security.
Public Health Implications
Increased contact between wildlife, livestock and people leads to increased risk of disease transmission, and biodiversity plays a crucial role in disease regulation by maintaining balanced ecosystems where no single species dominates, helping limit the spread of zoonotic diseases, with over 75% of emerging infectious diseases being zoonotic and often arising in areas where ecosystems and habitats have been disrupted.
Conservation Strategies and Adaptation Measures
Addressing the biodiversity crisis requires comprehensive strategies that combine mitigation of climate change with targeted conservation and adaptation efforts.
Protected Areas and Conservation
Expanding and effectively managing protected areas is crucial for biodiversity conservation. Mean coverage of Key Biodiversity Areas has increased from 25.8% in 2000 to 46.0% in 2024 in the marine environment, with similar progress on land (26.7% to 44.6%) and in freshwater (27.1% to 43.7%).
However, protection alone is insufficient. The protected status and offshore location did not protect One Tree Reef from heat stress bleaching and mortality, demonstrating that even well-protected areas cannot escape the impacts of climate change.
Ecosystem Restoration
Large-scale restoration efforts can help build ecosystem resilience and reduce extinction risks. Brazil launched the Arc of Restoration project to restore 24 million hectares of deforested and degraded lands of Brazilian Amazon by 2050, with the rapid growth of the restored forests expected to reduce the risk of tipping point, in addition to removing several hundred million tonnes of CO² per year.
Nature-Based Solutions
Nature-based solutions that work with natural processes can provide multiple benefits for both biodiversity and climate. These include reforestation, wetland restoration, sustainable agriculture practices, and the protection of coastal ecosystems like mangroves and salt marshes that provide both habitat and coastal protection.
Climate Corridors and Connectivity
Creating corridors that allow species to migrate in response to changing conditions is essential. These corridors connect protected areas and enable species to track suitable climate conditions as they shift across the landscape.
Policy and International Cooperation
Effective responses to the biodiversity crisis require coordinated action at local, national, and international levels.
The Kunming-Montreal Global Biodiversity Framework
At COP15 in December 2022, governments met in Montreal, Canada, and agreed on the new framework to address biodiversity loss, restore ecosystems and protect the rights of Indigenous Peoples. This framework sets ambitious targets for protecting and restoring nature by 2030 and 2050.
Climate Finance for Biodiversity
Private finance mobilised with public finance for biodiversity has more than doubled, from USD 748 million in 2021 to USD 1.8 billion in 2022, with preliminary estimates reaching almost USD 4 billion in 2023, however, these amounts are still far from those achieved in climate change (USD 16.1 billion on average over 2017-22).
Emissions Reduction Commitments
Ultimately, protecting biodiversity from climate change requires aggressive action to reduce greenhouse gas emissions. The future of the world’s coral reefs relies on strong greenhouse gas emissions reduction, and the same is true for ecosystems worldwide.
The Role of Indigenous Peoples and Local Communities
Indigenous peoples and local communities play a crucial role in biodiversity conservation and climate change adaptation.
Indigenous Peoples, people of African descent, and local communities are guardians of our nature, their traditional knowledge is a living library of biodiversity conservation, and they must be protected and be part of every biodiversity conversation.
Indigenous territories often harbor high levels of biodiversity and store significant amounts of carbon. Supporting Indigenous rights and incorporating traditional ecological knowledge into conservation strategies can enhance both biodiversity protection and climate resilience.
Emerging Research and Monitoring
Continued research and monitoring are essential for understanding and responding to the biodiversity crisis.
Early Warning Systems
Developing early warning systems that can detect when ecosystems are approaching tipping points is crucial for timely intervention. These systems monitor indicators such as changes in species composition, ecosystem productivity, and resilience to disturbances.
Climate Vulnerability Assessments
Comprehensive assessments of species and ecosystem vulnerability to climate change help prioritize conservation efforts and allocate resources effectively. These assessments consider factors such as exposure to climate change, sensitivity to climate impacts, and adaptive capacity.
Long-Term Monitoring Programs
Long-term monitoring programs, such as those tracking coral reef health on the Great Barrier Reef, provide essential data on how ecosystems are responding to climate change and the effectiveness of conservation interventions.
The Path Forward: Urgent Action Required
The evidence is clear: climate change poses an existential threat to biodiversity and ecosystems worldwide. The window for preventing the most catastrophic outcomes is rapidly closing, but meaningful action is still possible.
The Urgency of the Situation
The choices we make in the coming few years will determine the fate of our planet’s biodiversity and the future of life on Earth, as crossing tipping points is not inevitable, but the window for action is closing rapidly.
Previous studies of ecological tipping points suggest significant social and economic costs from the second half of the 21st century onwards, but findings suggest the potential for these costs to occur much sooner.
Integrated Solutions
Addressing the biodiversity crisis requires integrated solutions that simultaneously tackle climate change, habitat loss, pollution, overexploitation, and invasive species. Piecemeal approaches that address only one threat while ignoring others are unlikely to succeed.
Transformative Change
Incremental changes are insufficient. Goals such as the Aichi biodiversity targets may only be achieved through transformative changes across economic, social, political, and technological factors and not at current trajectories.
This requires fundamental shifts in how societies produce and consume resources, value nature, and make decisions about land use and development. It means transitioning to sustainable economic models that recognize the true value of ecosystem services and the costs of environmental degradation.
Hope and Opportunity
Despite the severity of the crisis, there are reasons for hope. Deforestation rates have declined in some regions, protected area coverage is expanding, and innovative conservation approaches are showing promise. Renewable energy technologies are becoming increasingly cost-competitive, making emissions reductions more achievable.
The knowledge and tools needed to address the biodiversity crisis exist. What is required now is the political will, financial resources, and collective action to implement solutions at the scale and speed necessary to prevent catastrophic biodiversity loss.
Conclusion
Climate change represents one of the greatest threats to biodiversity and ecosystems in Earth’s history. The impacts are already visible across the globe, from bleaching coral reefs to collapsing rainforests, from shifting species ranges to accelerating extinction rates. The scientific evidence is unequivocal: without urgent and comprehensive action to reduce greenhouse gas emissions and protect natural systems, we face the prospect of widespread ecosystem collapse and mass extinction.
However, the future is not predetermined. The choices made in the coming years will determine whether we can preserve the rich tapestry of life on Earth for future generations. By combining aggressive emissions reductions with targeted conservation efforts, ecosystem restoration, and support for Indigenous peoples and local communities, we can still prevent the worst outcomes and build a more sustainable relationship with the natural world.
The biodiversity crisis is ultimately a human crisis. The same ecosystems and species threatened by climate change provide essential services that human societies depend upon for survival and prosperity. Protecting biodiversity is not just about saving species for their own sake—it is about safeguarding the life support systems that make human civilization possible.
The time for action is now. Every fraction of a degree of warming matters, every hectare of habitat protected makes a difference, and every species saved represents a victory for the future of life on Earth. The challenge is immense, but so too is the opportunity to create a more sustainable and equitable world where both nature and humanity can thrive.
For more information on climate change and biodiversity, visit the Intergovernmental Panel on Climate Change, the International Union for Conservation of Nature, the United Nations Environment Programme, the World Wildlife Fund, and The Nature Conservancy.