World Biodiversity Day reminds us that the profound crises we confront are just different sides of the same coin
- By Katharine Hayhoe on
Farmland serves as a bulwark against desertification in India. Credit: Antonio Ciufo/Getty Images
When you hear the word nature, what comes to mind? For me, it’s the lakes of Southern Ontario, where I spent my childhood summers among its pink and gray granite rocks and shadowed pine forests. I picture the rock bass darting through the sunbeams in the water and hear the cicadas humming in the trees.
I grew up in the 1970s, and even then, nature was far from untouched. Acid rain and water pollution were already making headlines. Rachel Carson's Silent Spring had raised the alarm in 1962. Seven years later, the Cuyahoga River was ablaze for the 12th time. By 1970, the U.S. Clean Air Act was signed.
I still saw these issues as somehow separate from our ordinary lives, though. They were concerns for and on behalf of fish, plants or bees, I thought, not us. I took for granted clean air, abundant water and ample food, and a home unthreatened by fire or flood.
Fast forward to today, and those early alarms have become a deafening siren. While air pollution in the U.S. has declined, its impacts worldwide have skyrocketed. Today, more than one in every six deaths globally is caused by the pollution of our air, water, and soil.
Then there’s climate change: an invisible but devastating force that’s wreaking havoc on a planetary scale. The industrial revolution ignited our unhealthy dependence on fossil fuels; but what we often don’t realize is that nearly 80 percent of the CO2 emissions from burning coal, gas and oil, and close to 60 percent of all heat-trapping gas emissions, have been released since 1970. Choices made within my own lifetime are the main reason temperatures are now rising at an unprecedented rate, loading the weather dice against us. Every day now, we witness the impacts: record-breaking heat waves stressing power grids and health systems, supersized cyclones ravaging cities and refugee camps, wildfire smoke suffocating continents, and floods displacing millions.
The urgency and the injustice of the climate crisis compelled me to become an atmospheric scientist. I’m convinced it's the most immediate threat to our civilization and many of the countless species with whom we share this planet. But closely trailing climate change is another equally menacing crisis: the loss of biodiversity, which threatens all life on Earth.
The biodiversity crisis isn’t new, either. Over the last four centuries, humans have driven at least 680 mammal, bird, reptile, amphibian and fish species into extinction; but as with climate change, the rate of impact has escalated. Since 1970, WWF has documented a near 70 percent decline in populations of existing wildlife species; and across the more than eight million animal and plant species on earth, the human-induced extinction rate is estimated at tens to hundreds of times greater than natural rates. With so many species still undiscovered, these numbers vary widely; enough is known about the impacts of human activities on biodiversity, though, for ecologists to label the era we’re currently in as the “sixth extinction.”
All too often, though, many of us still think and act as I did when I was young: mistakenly assuming that, were our planet’s ecosystems to collapse, we could miraculously persist without the air, water, and essential resources they provide. This perspective endangers us all. Climate change, pollution and biodiversity loss have escalated to crisis levels that threaten not just flora and fauna, but humanity itself. It’s our collective survival that’s at risk.
Our ultimate goal is not merely to fix these crises, but to ensure a better future: for ourselves, for our children and for everyone and everything we love here on this Earth. However, this better future can only be reached by overcoming our self-made crises. Our ecosystems are, quite literally, our life-support systems. Without them, we cannot ensure stable global food systems and economies, let alone provide clean air and unpolluted water for the eight billion people who inhabit this planet. Our well-being and that of all life on Earth are fundamentally entwined.
Unlike other species, however, we have a choice. We can see what’s happening; we know we’re responsible; and we can still prevent catastrophe. But we don’t have much time. We can’t afford to tackle these crises with piecemeal solutions. We need comprehensive, multipronged strategies, everything from clean energy to educating women in low-income nations, that address climate, pollution, biodiversity—and health, poverty and other inequities—and we need them now.
The stakes are high: in the 2015 Paris Agreement, the world agreed to limit warming to “well below” 2 degrees Celsius, a threshold now set at 1.5 degrees C after scientists quantified the risks of additional warming. More recently, in December 2022, countries agreed to the Kunming-Montreal Global Biodiversity Framework. It addresses the main drivers of biodiversity loss and calls for the protection of 30 percent of land, ocean and freshwaters by 2030.
Policies implemented since the Paris Agreement have already reduced projected warming by end of century from about 4.5 degrees C to 2.8 degrees C. That’s a lot: but it’s still not enough. For these audacious plans to succeed, there cannot be any new fossil fuel development. Greenhouse gas emissions must be reduced and eventually eliminated through efficiency, improved land use and agricultural practices, and the clean energy transition. We must invest in nature, which has the potential to absorb up to a third of our carbon emissions. And we need countries to write and implement their own national biodiversity action plans, and funding to flow to climate mitigation, climate resilience and biodiversity in low-income countries and key conservation areas around the world, particularly those most vulnerable and most representative of the world’s ecosystems.
Nature offers a powerful ally in combating the catastrophic effects of human-induced climate change and ecosystem disruption, and the path to a net-zero, nature-positive world isn’t uncharted. The latest IPCC report shows how so many of the solutions to climate change are already here, from halting deforestation to accelerating electrification. Organizations like the Nature Conservancy and Project Drawdown offer resources like the Biodiversity Action Guide and the Drawdown Roadmap, illustrating how we can get started on actions that tackle multiple crises at once.
Implementing effective, nature-positive solutions is crucial to our fight against climate change. Greening low-income neighborhoods in large urban centres keeps them cool during heat waves, reducing socioeconomic inequities in health risks. But this action also filters pollution from the air; and absorbs rainfall to prevent floods, making the neighborhoods more climate-resilient. It provides places for people to be in nature, improving both our physical and mental health; it increases habitats for biodiversity; and it even takes up carbon. That’s at least six wins. Other solutions, from investing in public transportation to climate-smart agriculture, carry similar benefits for health and well-being, as well as pollution, biodiversity and climate.
Tackling the pollution, climate and biodiversity crises that stand between us and a better future is the biggest and most complex challenge we’ve ever faced. It demands an equally ambitious response from all of us: from the largest countries and companies in the world to each of us as individuals who can raise our voices to advocate for the changes we need.
Events such as Earth Day in April and World Biodiversity Day in May serve as potent reminders that the crises we confront are just different sides of the same coin. That’s why I constantly strive to reach beyond the artificial silos we impose on ourselves and others and focus on the end goal: saving ourselves and all others who share our home. Our future is in our hands, and together, I know, we can turn the tide.
This is an opinion and analysis article, and the views expressed by the author or authors are not necessarily those of Scientific American.
ABOUT THE AUTHOR(S)
Katharine Hayhoe is the chief scientist for the Nature Conservancy, a distinguished professor at Texas Tech University and the author of Saving Us: A Climate Scientist's Case for Hope and Healing in a Divided World.