Growing food, building housing and infrastructure, creating things, moving around – all of these things require that we use our planet’s natural resources. Throughout most of history, humanity’s demand for these resources was well within nature’s capability to renew them. Our biocapacity – the biologically productive land and sea area of the Earth, from cropland to kelp forests – used to be higher than our ecological footprint. But as the global population’s demand for more food products, timber, and construction space grows, the ability of the world’s ecosystems to absorb carbon dioxide emissions is shrinking, along with the ability of forests, rivers, and grasslands to renew themselves.

USING MORE THAN WE CAN PRODUCE

Around the early 1970s, we started using more of Earth’s supply of natural goods than it could sustainably generate. This overconsumption of food and energy resources led us to generate harmful greenhouse gas emissions beyond our planet’s capacity to absorb them. The impact of this is now evident in many forms: from climate change to deforestation, loss of biodiversity, and poor air quality.1 And, most years, our ecological footprint only grows larger.

There are also economic impacts of overshooting the planet’s biocapacity. If we cannot produce enough food to cover our rising demand, the resulting imbalance is likely to lead to a perfect storm of food insecurity and economic distress, with inflation and social unrest being some of the early consequences, and complete economic collapse being the end point.

EARTH OVERSHOOT DAY

In order to raise awareness about our overconsumption and misuse of the planet’s limited resources, Earth Overshoot Day was launched in 2006 by the research organisation Global Footprint Network. The date on which Earth Overshoot falls in a specific year is calculated by dividing the world biocapacity (the amount of resources generated by the Earth in that year) by the world’s ecological footprint (our consumption of natural resources in that year), and multiplying the quotient by 365 (the number of days in a year).

For the past few years, the resources that humanity has been using annually would require 1.75 Earths to provide sustainably.2 If we keep increasing our consumption at the current rate, Overshoot Day will happen earlier every year – and before the middle of the 21st century, we will need the resources of two Earths.

HOW TO #MOVETHEDATE

In order to move the date of Earth Overshoot Day back to later in the year, we need to both reduce our ecological footprint and make far more efficient use of the finite resources available to us. This needs to be tackled on many fronts, but one of the most effective ways to combat overconsumption is to change the way we eat – and transform our food system.

A global shift to plant-based food would reduce the resource load on the world’s croplands – growing pulses and other crops for direct human consumption instead of animal feed is far more efficient and emits much less greenhouse gas than methane-heavy livestock farming. And importantly, taking this approach will help to ensure that no one is left behind.

In summary, Earth Overshoot Day presents an opportunity to rethink our consumption habits and properly value the resources generated by our planet. There are many things that we can do to move the date to later in the year. While we need to do all of those things, making the shift to plant-based eating is one of the most impactful and effective ways to start.3