Source: Earth, PD http://bit.ly/1JPJLLL World Pop Graph, CC http://bit.ly/1CQGtWX World Pop Map,CC http://bit.ly/1yRJN2n Deforestation, PD http://bit.ly/1Ci1x9N Farming, CC http://bit.ly/1ziLVPq Parinacota, CC http://bit.ly/1ziLYe8 Alternative Farming, CC http://bit.ly/1za02Ix Pump Jack PD http://bit.ly/1Hmw5Kw Hectare, PD http://bit.ly/1wFwRah U.S. Map, PD http://bit.ly/1EsIxG7 India Map, CC http://bit.ly/18A6kH3 Earth PD http://bit.ly/1ESoBKp
I'm Jensen Morgan. We're going to talk about some great concepts in environmental science today. So let's get started. Today's topic is human population growth.
What I want to focus on is the state of human population growth today, and the environmental impacts it is having. As I'm talking, the world's current estimated population is somewhere around 7.2 billion. Only 55 years ago, that number was less than half of that, at around 3 billion.
You can see evidence of this when looking at the world population map. This map colors a country based on its population. The darker the color, the higher the population is. Developing countries like India and China are a much more populous than countries like the US because they're still in the lag time where death rates are dropping but birth rates are still very high.
The current population of the world, at 7.2 billion, is considered by many scientists to be unsustainable. Humans are a major cause of environmental degradation, as we did for fossil fuels and deforested areas for meat production. Unfortunately, in countries where people are poorest, populations tend to be highest.
The combination usually results in people having no alternative but to degrade their local ecosystems in order to provide for themselves. Humans' rate of resource consumption and environmental degradation is increasing proportionally to our population growth. Essentially, we have a big, big problem.
Our planet has a finite amount of land, water, and energy resources, some of which are renewable and non-renewable. Unfortunately, at our current rate of growth and consumption, we were sucking up our non-renewable ones, such as fossil fuels, and degrading our renewable ones such as safe drinking water and forest land.
The UN projects three possible futures of population growth by 2100 based on low, medium, and high birth rate projections. The impacts on our environment and human quality of life will vary dramatically, depending on which of the scenarios becomes reality. When talking about human population growth and its relationship to the environment, it is important to understand our key concepts for today, called ecological footprint.
Ecological footprint is the amount of resources required to sustain an individual or a population. It is usually measured in hectares, which is a measurement of land area, which comes out to 10,000 square meters. It is the metric system is equivalent to aces. Let's give this concept a little more context.
In the US, the average standard of living creates an ecological footprint, which requires five hectares of land area per person. This is similar to about nine football fields of land. According to the World Bank, the US currently has available 0.5 arable hectares of land per person.
This means there's less land available in the US than we require with our average standard of living. This is made possible because much of the land which supports US standard of living is borrowed from other countries by importing much of our food in commodities. In other developing countries, such as India, the average standard of living requires only 0.5 hectares of land, which is less than 1 football field.
If the entire world population required the same standard of living as the US, we would need three Earth's to support it. In terms of the varying types of environmental impacts of human population growth, there are many. Pollution from cars and industrial processes have caused significant atmospheric pollution all over the world.
CO2 production has altered the planet's heating and cooling systems, creating a phenomenon called climate change. Safe drinking water resources have been polluted, preventing millions of people all over the planet from having any safe drinking water. Sprawl of cities and farming has destroyed habitat and food resources, threatening biodiversity of our ecosystems and causing millions of species to go extinct, even just in the last couple centuries.
Overexploitation from too much hunting and fishing has also endangered species. Meat production and agriculture have encouraged huge swatches of forest to disappear, which only increases the impacts of climate change and air pollution. The resources needed to support and maintain developed nations lifestyles is resulting in the depletion of non-renewable resources, such as fossil fuels and various rare materials.
Now let's have a recap. Today we talked about human population growth, how it has dramatically increased in the last century, and how it is having negative environmental impacts on our planet. In places like India and other developing countries, population growth is high along with poverty. The result is a much higher rate of environmental degradation as people try to provide for their basic needs.
If humans all required the same standard of living that people have in the US, we would need three entire Earth's, which is a very large ecological footprint. Speaking of which, don't forget a key term for today, ecological footprint. Ecological footprint is the amount of natural resources required to sustain an individual or a population.
Well that's it for this tutorial. I help learning this concept has been helpful. Looking forward to next time. Bye.