Climate Action Supports Nature’s Survival – Evidence from En-ROADS

By Climate Interactive
December 17, 2024

Arguably the greatest impacts of climate change will be on the Earth’s natural systems and non-human species, yet the majority of climate change research and policy focuses solely on the impacts of climate change on human beings (Malhi Y, et al. 2020). To help address this gap, we highlight below some of the many benefits to nature from taking climate action. These actions and more can now be explored in our En-ROADS Climate Solutions Simulator.

The big picture: Actions that reduce warming preserve the natural world.

Climate change has a profound impact on nature. Rising temperatures disrupt ecosystems, forcing plants, animals, and other forms of life to either adapt, move to new habitats, or face population losses, ultimately leading to declines in biodiversity. However, by taking climate action, the world can lower greenhouse gas emissions and limit temperature increases that are driving these impacts on nature.

There are now five key measures of the impact of global warming on the health of natural systems that we can assess with various En-ROADS climate action scenarios:

While many combinations of climate actions can achieve similar outcomes, we’ve chosen a few illustrative examples below to highlight the possibilities for reducing these impacts of climate change on nature.

Saving energy can protect ecosystems like rainforest and tundra.

Climate change can force ecosystems to shift from one type to another—for instance, tropical rainforest transitioning to savanna, or Arctic tundra becoming deciduous forest. Warming changes weather patterns and water cycles, causing some plant species to thrive and others to decline. Such shifts also disrupt animal interactions, such as predator-prey relationships and pollination. These disruptions affect not only biodiversity but also the people who depend on stable ecosystems for food, jobs, and clean water.

Improving energy efficiency by 5% per year could save 580 million hectares of land—approximately the area of the Amazon Rainforest—from shifting to a different ecosystem by 2100. This could be accomplished by insulating buildings, conserving energy, and replacing older appliances and industrial processes with more efficient models and methods.

Improving energy efficiency lowers emissions by decreasing the total energy demand, which reduces the reliance on fossil fuels. For example, this scenario increases the energy efficiency of buildings and industry from the current 1.2% per year rate of improvement to 5% per year. This results in 629 fewer gigatons of CO₂ emitted by fossil fuels by 2100 even without any other actions. Compared to the Baseline Scenario, this action reduces warming by 0.4°C by 2100, helping to preserve ecosystems.

Carbon pricing can prevent desertification.

One type of ecosystem shift is the expansion of dry lands such as deserts. As temperatures rise, more areas become dry and desert-like because there isn’t enough water in the soil to support abundant plant growth. Warmer air can hold more moisture, leading to increased evaporation from land. At the same time, changing rainfall patterns can reduce water availability. Without the ability to grow food and support livestock, nearby communities can experience exacerbated food and water scarcity as deserts expand. Drier soils are also more likely to create dust in the air, which increases air pollution, leading to substantial public health impacts, such as higher rates of asthma and cardiovascular diseases.

However, implementing a carbon price of $150/ton of CO₂ could prevent 182 million hectares—an area roughly the size of Mexico—from turning arid by 2100. For example, this scenario increases the average carbon price globally from $5/ton CO₂ currently to $150/ton CO₂, slightly higher than Sweden’s current carbon price of $131/ton CO₂. Carbon pricing increases the cost of energy sources based on the amount of carbon dioxide they emit. This encourages a shift away from fossil fuels and promotes the use of renewable energy sources.

Avoiding fluorinated gases (F-gases) can preserve animal habitats.

Animals are adapted to live in specific habitats and rely on the plants and other animals that thrive there for food. For example, animals in colder climates have evolved features like thick fur and layers of blubber to survive the cold. Many also have seasonal behaviors, such as nesting and migration, that are closely tied to the cycles of other species. However, as temperatures rise, many species face shrinking habitats—or even the complete loss of the environments they depend on. This poses severe threats to global biodiversity, as species struggle to adapt or migrate to suitable habitats.

Two percent of mammals, birds, and butterflies could be protected from losing over 50% of their habitat by 2100, by preventing the release of F-gases from refrigerators, aerosol sprays, and air conditioning units.

Fluorinated gases (F-gases) are human-created chemicals found in refrigerators, air conditioners, and aerosols (e.g., HFCs). Although F-gases are released in very small amounts relative to CO₂, they are much more effective at trapping heat than CO₂, making them extremely powerful greenhouse gases.

Action on F-gases involves policies like transitioning to alternative refrigerants, including ammonia or hydrocarbons, as well as capturing and destroying F-gases in obsolete equipment. This scenario represents an 86% reduction in F-gas emissions through the wholehearted adoption of best practices such as recovery, recycling, and destruction of F-gases in equipment, as well as the use of alternatives.

Tree planting and forest protection can save ocean animals.

Warming waters lead to significant losses in marine life. Most fish, for example, are cold-blooded, meaning that they rely on their environment to regulate their body temperature and metabolism. Warmer ocean temperatures force marine life to migrate and reduce the nutrient mixing that feeds plankton, affecting the entire ocean food web. These losses undermine food security for millions of people who depend on marine resources and reduce the ocean’s ability to sequester carbon.

Eliminating human-caused deforestation and mature forest degradation, combined with a massive tree-planting effort, could save 1% of marine animals by 2100.

Deforestation and forest degradation release CO₂ from trees and soil into the atmosphere while also reducing the land’s ability to absorb and store carbon. This scenario combines a halt to deforestation and the harvesting of mature forests (older than 100 years) for paper, lumber, and bioenergy by midcentury, with an effort to plant trees on an additional 550 million hectares of land. For comparison, this afforestation effort would require a combined amount of land equal to the area of India plus Kazakhstan. In addition to preventing emissions of CO₂, this scenario also increases the amount of carbon forests remove from the atmosphere.

Reducing fossil fuels can save marine animals from extinction.

Endemic species, which live in limited areas and cannot easily adapt to environmental changes, face a heightened risk of extinction from climate change. Examples include Hawaiian monk seals, vaquita porpoises, and polar cod. Their loss not only reduces global biodiversity but also disrupts ecosystems that rely on their unique roles. Polar cod, for example, is a major food source for other fish, marine mammals, and seabirds in the Arctic.

Cutting coal, oil, and gas use in half could reduce the risk of extinction for 8% of endemic ocean animal species by 2100.

Corporate commitments to end coal financing, bans on gas stoves, and other methods of shifting away from fossil fuels are powerful ways to reduce temperature increase. This scenario models a 50% reduction in fossil fuel use that phases in over ten years.

Combining these actions leads to significantly greater protection for biodiversity and ecosystems.

Combining these actions together into a single scenario reduces warming by 2100 to 1.9°C above preindustrial levels, delivering significant benefits to nature. In this scenario, we can save:

1.7 billion hectares of land—slightly larger than the area of Russia—from shifting to a different ecosystem
358 million hectares of land—slightly larger than the area of India—from becoming severely dry
16% of mammal, 17% of bird, and 27% of butterfly species from losing more than half of their habitat
5% of marine animals
17% of marine endemic animal species from risk of extinction

The significance of this for the natural world would be monumental for centuries to come.

Try it for yourself

What combinations of actions could save 30% of insect species from losing most of their habitat? What combination of actions could save an area the size of Argentina (278 million hectares) from becoming dry land? Explore these impacts in the En-ROADS Simulator using the Impacts graph menu.

Try it in En-ROADS

A note on methodology

To create these impact graphs for En-ROADS, we used data from external research studies that quantified the impact of climate change on natural systems at various temperatures or Representative Concentration Pathways (RCPs). We formulated a relationship between temperature and the impact in the study and input that relationship into En-ROADS as an equation. The research sources are included in each graph description, accessible by clicking on the arrow in the top left corner of the graph’s title bar in the En-ROADS simulator. For more information on how we modeled these impacts, see the En-ROADS Technical Reference.

Acknowledgements

Climate Interactive has co-developed En-ROADS with MIT Sloan. For this work, we are grateful to the V. Kann Rasmussen Foundation for their support to bring this analysis and modeling in En-ROADS to you. We would also like to extend our thanks to the external advisors who helped to shape this work through their valuable feedback during the development process.

To our knowledge, this is the first publicly available tool that explicitly models the effect of climate policy on the survival of so many aspects of nature. We hope you find it useful for your work! Let us know how you are using these insights, or any feedback you have, by dropping us a message here.