The Human Footprint: 7.6+ Billion People on Earth
In flesh and blood, 7.6 billion humans inhabit Earth. This number is estimated to increase to 8.3-10.9 billion in 2050.
We erect cities, trim forests and alter the environment. In fact, 75% of land outside of ice sheets are managed by us.
Because of our massive human footprint, scientists are proposing we have already entered a new epoch called the “anthropocene”.
Let’s examine the extent of the human footprint on Earth.
The changing landscape
As population increases to 7.6+ people, food production is set to match this increase. Now, there’s over 5 billion hectares designated for agricultural land compared to just 1 billion in 1800. So that means about 40% of land is for feeding the planet.
Forests cover approximately 30% of Earth’s land surface and are important carbon sinks. But as urban area expands, forest cover is in the decline. According to the World Resource Institute, we have already lost 80% of the world’s natural forests due to our human footprint.
Approximately 15% of land is protected because their recognized as areas with ecological value. But currently, extinction rates are 100 to 1000 times above normal. A lot of critical biomes are in desperate need of protection to preserve biodiversity.
Global human footprint index
The emergence of humans has left a profound impact on the planet. We can measure the cumulative impact of human disturbance in nature through the global human footprint index:
The Wildlife Conservation Society has devised the global human footprint index which includes the following classes:
- Built environment
- Population density
- Electric infrastructure
- Cultivated lands
- Pasture lands
- Roads and railways
Currently, 75% of our land surface is experiencing human pressures. And from 1993 to 2009, population has grown 23%. But the human footprint has increased by just 9%.