Columbia Resilience

What is Overshoot?

This essay is the first in a series of posts on the current ecological predicament of Planet Earth.  I am not a scientist, so what I share here are distillations from scientists and other thinkers whom I trust – people like Nate Hagens, Richard Heinberg, Jason Hickel.  Resources by these and others are listed on the Resources page. 

On the home page here you can see a reference to the term “overshoot.”  Overshoot is the condition in which a population uses up more resources than are available to it over the long term and produces more waste than its natural surroundings can absorb. Resources are both renewable (soil, timber, ocean fish) and non-renewable (fossil fuels, minerals).  

The author John Michael Greer gives an example of overshoot in his book The Ecotechnic Future, page 5.  Imagine, he says, field mice in a meadow.  There are good years of abundant grass seed where the mouse population climbs and then bad years where the grass is insufficient to support them, and the population is reduced.  Then imagine if the mice were to receive “a surplus of energy…that happens only once…a truck full of grain overturn[s] on the nearby freeway and spill[s] its load in their meadow.”  The mouse population soars far beyond the meadow’s carrying capacity and the rate at which the grain is consumed also rises, until the grain begins to run short.  At that point the mouse population is in overshoot because it cannot replicate the amount of grain that it received in the one-time surplus, and most of the mice will die of starvation.  In addition, the meadow will not return to its original carrying capacity because overshoot leads to habitat damage; the remaining mice will eat as much of it as possible to survive.  William R. Catton, author of the monumental book Overshoot, described it as “in essence stealing from one’s own posterity.”

Overshoot for humans is calculated on an annual basis.  The annual Earth Overshoot Day, the day on which we will have used up the resources which can be renewed each year, can be found at  In 2022 the date was July 28.  On this website you can also see overshoot days by country.  A particular country’s overshoot day is the day Earth Overshoot Day would occur if all people on earth consumed like the people in that country.  America’s overshoot day this year is estimated to have been on March 13, as illustrated by this graphic.  

There are 50 countries which have no overshoot day.  The vast majority of them are located in the Global South – countries such as Bangladesh, Kenya, Nicaragua, Somalia, and Yemen.  

Our task as people living in the Global North is to cut back our consumption of resources so that we do not continue to live in overshoot.  We will explore what this means in coming posts.