It’s no secret that the planet faces serious environmental concerns from water and air pollution to deforestation. While the causes are complex, one significant contributor to the problem is population growth. Understanding the relationship between population growth and environmental issues may be the first step toward identifying real solutions.
TL;DR (Too Long; Didn't Read)
Population growth is the increase in the number of people living in a particular area. Since populations can grow exponentially, resource depletion can occur rapidly, leading to specific environmental concerns such as global warming, deforestation and decreasing biodiversity. Populations in developed countries trend toward using substantially more resources, while populations in developing countries feel the impacts of environmental problems more quickly.
How Population Growth Works
The concept of population growth is tricky because populations can grow exponentially – similar to the way a bank or credit card company compounds interest. The formula for exponential population growth is N=N0ert where N0 is the starting population, e is a logarithmic constant (2.71828), r is the rate of growth (birth rate minus death rate), and t is time. If you plot this equation, you see a curve arching upward over time as the population increases exponentially, assuming no change in the rate.
This concept might be easier to visualize with actual figures. From the beginning of time on Earth to the start of the 20th century, the population of the planet grew from zero to 1.6 billion. Then, thanks to many factors, the population increased to 6.1 billion in just 100 years, which is an almost fourfold increase in the number of humans over a relatively short period.
Populations and Environmental Issues
More people require more resources, which means that as the population increases, the Earth’s resources deplete more rapidly. The result of this depletion is deforestation and loss of biodiversity as humans strip the Earth of resources to accommodate rising population numbers. Population growth also results in increased greenhouse gases, mostly from CO2 emissions. For visualization, during that same 20th century that saw fourfold population growth, CO2 emissions increased twelvefold. As greenhouse gases increase, so do climate patterns, ultimately resulting in the long-term pattern called climate change.
The Biggest Impacts
The use of resources and the impact of environmental issues are not equal around the globe. People in developed countries require substantially more resources to maintain their lifestyles compared with people in developing countries. For example, the United States, which contains 5 percent of the world’s population, currently produces a full 25 percent of CO2 emissions.
People in developing countries tend to feel the impacts of environmental problems more acutely, especially if they live in coastal areas directly affected by sea level rise and the extreme weather events that accompany climate change. The most vulnerable populations also experience decreased access to clean water, increased exposure to air pollution and diseases – which may result from decreased biodiversity – and may feel the impact more immediately as local resources including plants and animals deplete.
While the interconnected problems of population growth and environmental issues seem overwhelming, it is important to remember that humans can make changes that positively impact the planet. One good starting point is understanding and applying the concept of sustainability, which is the opposite of resource depletion. Sustainability describes a model of resource usage in which the current generation uses only the resources the Earth provides indefinitely (like solar or wind power instead of burning fossil fuels) to ensure that future generations inherit resources.
About the Author
Melissa Mayer is an eclectic science writer with experience in the fields of molecular biology, proteomics, genomics, microbiology, biobanking and food science. In the niche of science and medical writing, her work includes five years with Thermo Scientific (Accelerating Science blogs), SomaLogic, Mental Floss, the Society for Neuroscience and Healthline. She has also served as interim associate editor for a glossy trade magazine read by pathologists, Clinical Lab Products, and wrote a non-fiction YA book (Coping with Date Rape and Acquaintance Rape). She has two books forthcoming covering the neuroscience of mental health.