Where have all the species gone? Learn about the impacts of climate change on nature » Yale Climate Connection

The tiny flying fox, the cheerful oriole, and the freshwater mosquitofish recently lost protection under the U.S. Endangered Species Act, and for no good reason. They have been declared extinct.

They are among 21 species that have lost federal protection due to extinction nationwide, a sign of more losses to come as the ravages of climate change become increasingly severe.

Delisted species include Guam's lesser Mariana fruit bat and the San Marcos Gambusia fish, which are endemic to Texas. Eight of the species on the list are Hawaiian birds.

Hawaii is known as ground zero for the loss of biodiversity, a healthy mix of species, genetic heritage and ecosystems. Of the nearly 1,300 species (including plants and animals) protected by the U.S. Endangered Species Act, a large number live in the Hawaiian Islands.

In the 20th century alone, species are going extinct at the same rate as previous mass extinction events. Over the past 66 million years, animals have disappeared 30 to 120 times faster than at other times.

The main driver of biodiversity loss is land conversion, primarily from forests, grasslands or wetlands to agriculture – humans have already transformed 70% of the Earth’s land that is not covered by ice. Humans also contribute to pollution and allow invasive species to spread in ways they wouldn't otherwise. Recognizing this driver means we already know a solution: protecting land in a variety of ways, from creating nature reserves to developing policies to stop deforestation.

But now climate change is exacerbating an already precarious situation. This also complicates the solution.

Compounding impacts of climate change on biodiversity loss

A 2024 study published in the journal Global Change Biology estimates that an additional 17% of species on Earth will disappear as a direct result of climate change.

Since the Industrial Revolution, the Earth has warmed by about 2°F. How does this relate to plant and animal life? everything.

40% of Arctic sea ice has melted since the late 1970s, and nearly 60% of the world's ocean surface experienced at least one marine heat wave in 2021 alone. If current rates of ocean warming continue, the United Nations predicts that all coral reefs—the most biodiverse ecosystems on Earth—could bleach by the end of the century, destroying a wide range of marine life.

On land, forests have been weakened by severe drought. Climate change is exacerbating the spread of invasive species, with native species forced to move to higher latitudes or higher altitudes to escape increasingly warm temperatures. Climate change is changing weather patterns that have kept ecosystems functioning for millions of years. The pace of climate change is already making it harder for many species to adapt and thrive.

This is just the beginning of future climate impacts. In the Global Tipping Points 2023 report, scientists warn that as the planet warms, it is dangerously close to exceeding important natural thresholds that will cause irreversible harm to ecosystems and human life. These include the melting of Arctic ice caps and permafrost, the destruction of coral reefs, and the collapse of the Atlantic Meridional Overturning Circulation (the powerful ocean current that circulates water between the Atlantic and the Arctic).

Read: Atlantic circulation collapse? New clues about fate of critical conveyor belt

To understand how to help avoid the worst climate impacts on plant and animal life, researchers are delving into the links between climate change and biodiversity. For example, a group of conservation biologists recently analyzed climate and biodiversity models from 1900 to 2050., Their paper compares how land use changes have affected biodiversity in the past and how this may develop in the future depending on factors such as land conservation policies and greenhouse gas emission reductions.

The results are both optimistic and alarming.

In models that do not account for climate change, existing and future land protection efforts are shown to help slow or even reverse biodiversity loss in coming decades. This is a strong argument for continuing to implement practical land conservation policies.

But when climate change yes With this in mind, their research found that curbing biodiversity loss becomes more challenging, with increased emissions leading to greater damage to species and ecosystems.

This will also have a profound impact on human life. One reason? As climate change continues, many scientists believe communities will need to rely more on healthy ecosystems to remain resilient amid escalating impacts. For example, in coastal areas, people may rely on saltwater marshes to buffer against rising sea levels.

What the world can do to reduce biodiversity loss and Climate change?

There are practical steps humans can take to mitigate the effects of climate change and biodiversity loss. In a paper published in the journal Bioscience, Brazilian scientists propose some key directions:

• Protect carbon stocks and sinks by protecting land and oceans, two systems that have historically naturally stored more than half of humanity’s historical emissions. The researchers singled out the Amazon, Congo Basin and Southeast Asia as extremely biodiverse ecosystems and among the largest natural carbon stores on Earth.
• Stop expanding agricultural land. Nearly 40% of the earth's land is used for agriculture, which is the main source of land conversion, resulting in the destruction of nearly 20% of the Amazon rainforest. Policies that limit agriculture to land that has been converted to farmland will protect biologically rich places that often double as natural carbon storage sites.
• Integrating biodiversity into business models. Companies often promote their values ​​and goals related to protecting nature, and they are increasingly focusing on science-based climate action goals. But these plans often lack specific targets related to biodiversity.

The power of will in promoting biodiversity

The situation is urgent, but not all is lost. In a recent opinion piece published in Philosophical Transactions of the Royal Society B, ecologist Erle Ellis argued that humans have underestimated the power of desires, especially those related to changing the way people interact with nature. In other words: we can design solutions to problems caused by humans.

“When these transformative capacities to shape environments are combined with sociocultural adaptations that enable societies to more effectively shape and live in changing environments, the socioecological scale and intensity of these changes accelerates,” Ellis writes.

For example, researchers from across Canada, the United States, and Mexico are currently working on a biodiversity and climate change assessment project that will help identify meaningful ways forward.

The next big step will be to combine the power of desire with science to help develop land- and climate-based solutions to protect as many species as possible – including humans.

James Arnott is executive director of the Aspen Institute on Global Change. Caitlin Sullivan is a freelance journalist. She covers health, science and the environment. This article was written in collaboration with Energy Innovation and the Aspen Institute on Global Change. Both organizations are Yale Climate Connect content sharing partners.