Population Growth - Environmental Impact

Human population growth is the number one threat to the world's environment. Each person requires energy, space and resources to survive, which results in environmental losses. If the human population were maintained at sustainable levels, it would be possible to balance these environmental losses with renewable resources and regeneration. But our population is rapidly growing beyond the earth's ability to regenerate and sustain us with a reasonable quality of life. We are exceeding the carrying capacity of our planet.

We need to limit our growth voluntarily, and promote contraceptive use, before Nature controls our population for us with famines, drought and plagues. Our children's future depends on us.

As of October 2019, the world population is over 7.7 billion people, and growing.. The United Nation projects the world population for the year 2050 could range from 7.9 billion to 10.9 billion, depending on the actions we take today.

Population Facts - The future

The information in the following four sections was found in Urbanization on Water Shortage in Face of Climatic Aberrations written by Mrinmoy Majumder. This book can be found online at: http://www.springer.com/us/book/9789814560726.

Scarce Water

Water scarcity already affects every continent. Around 1.2 billion people, or almost one-fifth of the world’s population, live in areas of physical scarcity, and 500 million people are approaching this situation. Another 1.6 billion people, or almost one quarter of the world’s population, face economic water shortage. Depending on future rates of population growth, between 2.6 billion and 3.1 billion people may be living in either water-scarce or water-stressed conditions by 2025.

Scarce Cropland

Escalating soil and land degradation is destroying crop and pasture land throughout the world, with more than 10 million hectares of productive crop land so severely degraded they have to be abandoned each year. In addition, salinization is causing loss of about 10 million hectares per year. Because of the losses, approximately 30 percent of the world’s cropland has been abandoned during the past 50 years. The number of people living in countries where cultivated land is critically scarce is projected to increase to between 600 million and 986 million in 2025.


Most of the world’s ocean fisheries are already being fished to their maximum capacities or are in decline. Our appetite for fish is exceeding the ocean’s ecological limits with devastating impacts on marine ecosystems.


Deforestation Figure 2: Global Forest Loss https://www.flickr.com/photos/gridarendal/31514312974
Compare to Figure 3 below to see where large population growth and deforestation overlap.

According to the U.N. Food and Agriculture Organization Global Forest Resources Assessment 2005, the net loss in forest area at the global level during the 1990s was an estimated 94 million hectare - an area larger than Venezuela and equivalent to 2.4 percent of the world’s total forests. Throughout the 1990s many countries with high rates of deforestation also had rapid population growth. In 1995, close to 1.7 billion people lived in 40 forest-scarce countries, those with less than one-tenth of a hectare of forest per capita. By 2025, 4.6 billion people will live in forest-scarce countries. By then watersheds in China, Nepal, Thailand, and Vietnam are projected to be critically degraded as a result of the loss of forest cover.

Global Warming

According to the EPA, “Global warming refers to the recent and ongoing rise in global average temperature near Earth’s surface. It is caused mostly by increasing concentrations of greenhouse gases in the atmosphere. Global warming is causing climate patterns to change.”

“Climate change,” they go on to say, “refers to any significant change in the measures of climate lasting for an extended period of time. In other words, climate change includes major changes in temperature, precipitation, or wind patterns, among other effects, that occur over several decades or longer.”

Humans are largely responsible for recent climate change. The choices we make today will affect the amount of greenhouse gases we release in the atmosphere in the near future and for years to come. You can take action. You can take steps at home, on the road, and in your office to reduce greenhouse gas emissions and the risk associated with climate change.

The added challenge with carbon emissions is that any CO2 put in the atmosphere can remain there for hundreds of years. Due to this extremely long residence time (100-1,000 years), halting fossil emissions immediately is imperative.

Species Extinction

The Center for Biological Diversity argues that, “we are in the midst of the Earth’s sixth mass extinction crisis. Harvard biologist E. O. Wilson estimates that 30,000 species per year (or three species per hour) are being driven to extinction. Compare this to the natural background rate of one extinction per million species per year, and you can see why scientists refer to it as a crisis unparalleled in human history.”

According to Rahul Mittal, more than 1.1 billion people live in areas that conservationists consider the richest in non-human species and the most threatened by human activities. While these areas comprise about 12 percent of the planet's land surface, they hold nearly 20 percent of its human population. Extinction is the most serious, utterly irreversible effect of unsustainable human population, he states in Impact of Population Explosion on Environment.

Consumption Plus Population


When population growth is coupled with excessive consumption of resources, problems multiply. Currently, 20 percent of the world's people in the highest-income countries account for 86 percent of the total private consumption expenditures, while the poorest 20 percent consume only 1.3 percent. The unequal distribution of wealth and resources leads to obvious waste and excess in the wealthy nations, and suffering in the resource-starved regions.

For more information on this problem and some suggested remedies, visit these websites:

Take an Ecological Footprint Quiz! Learn about your personal consumption habits. - http://www.myfootprint.org

The Center for the New American Dream - https://newdream.org/

Population Reference Bureau - http://www.prb.org/

U.S. Census Bureau Population Estimates - http://www.npg.org/library/population-data.html

World Population Clock - https://www.worldometers.info/world-population/

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