Ecological Debt Day

Ecological Debt Day, also known as “Earth Overshoot Day”, is the calendar date each year in which the total resources consumed by humanity will exceed the capacity for the Earth to generate those resources that year. It is calculated by dividing the world biocapacity, the number of natural resources generated by the earth that year, by the world Ecological Footprint, humanity’s consumption of the Earth’s natural resources for that year, and multiplied by 365, the number of days in one Gregorian calendar year; expressed as:

$( \text{World Biocapacity} / \text{World Ecological Footprint} ) \times 365 = \text{Ecological Debt Day}$

When viewed through an economic perspective, Ecological Debt Day/Earth Overshoot Day represents the day in which humanity enters deficit spending, scientifically termed “overshoot”. In recent years this issue has gained notoriety as it appears to represent a trend rather than a freak occurrence.

History

Though humanity first went into overshoot in 1986, Ecological Debt Day was first observed on December 19, 1987. Before that date, humanity’s consumption of the Earth’s natural resources was outweighed by the Earth’s ability to regenerate its resources. To elicit discussion on the topic of natural resource consumption, the New Economics Foundation (NEF) marked Ecological Debt Day on that calendar year. Every year since then, NEF has calculated the calendar date of Ecological Debt Day for each subsequent year using the above formula. Ecological Debt Day has on average, each year fallen on an earlier date than the previous year. The authors of Ecological Debt Day argue that this fact constitutes a notorious trend in human society, in which humanity is falling deep into ecological debt.

The correlation between the development of a country using HDI and its natural resource consumption

Year	Overshoot Date
1987	December 19
1990	December 7
1995	November 21
2000	November 1
2005	October 20
2007	October 26
2008	September 23
2009	September 25
2010	August 21
2011	September 27
2012	August 22

Underlying factors

Ecological Debt Day is founded upon two scientific measures; humanity’s Ecological Footprint and the Earth’s biocapacity.

Humanity’s Ecological Footprint for the specific calendar year is an important component of both calculating Ecological Debt for that year and for the general idea behind Ecological Debt Day. One’s Ecological Footprint, be it of the world, a nation, a town, or of an individual represents the impact that entity made on the Earth that year by consuming a set amount of the Earth’s resources. The general Ecological Debt of each year is calculated by factoring in the world’s Ecological Footprint, however, each nation’s individual date on which it will reach Ecological Debt can be calculated by substituting that nation’s Ecological Footprint for a specific year in place of that of the world’s.

The other leading factor in determining date on which Ecological Debt occurs for a given year is the biocapacity of the Earth for that year. By engaging in activities that diminish the production cycles of natural resources, which can be the resources themselves, such as depleting forests for timber, humanity lessens the Earth’s biocapacity so that the number of resources able to be produced that year will be less than that of the year before. When viewed in terms of monetary debt, this idea can seen as compounding interest on an unpaid loan. Due to this factor, humanity’s over-consumption of the Earth’s natural resources is shown to be unsustainable as the Earth’s biocapacity will eventually collapse should this behavior continue. The Global Footprint Network, a partner of NEF, has calculated that humanity used 40% more resources in 2008 than the Earth was able to produce that year.

Interplay of factors

Ecological Debt Day draws on the fact that due to these resources being finite, humanity's recent trend of consuming more resources than the Earth can produce each year constitutes a negative, unsustainable trend, termed overshoot. Ecological Debt Day is conveyed using economic imagery of monetary debt as a means of reaching the general public rather than just the scientific community. Since the financial credit crunch of 2008, the phrase environmental credit crunch has also entered into use to convey the risks and consequences of consistently relying on finite resources.

Further reading

• Easterling, William E. (2007). "Climate change and the adequacy of food and timber in the 21st century.". Proceedings of the National Academy of Sciences 104 (50): 19679. doi:10.1073/pnas.0710388104. 
• "WWF: human consumption is outpacing earth's capacity". EurActiv.com. October 26, 2004. Retrieved March 1, 2009. 
• "Planet enters 'ecological debt'". BBC News. October 9, 2006. Retrieved March 1, 2009. 
• Wackernagel, Mathis; Niels B. Schulz, Diana Deumling, Alejandro C. Linares, Martin Jenkins, Valerie Kapos, Chad Monfreda, Jonathan Loh, Norman Myers, Richard Norgaard, and Jorgen Randers (2002). "Tracking the ecological overshoot of the human economy". Proceedings of the National Academy of Sciences 99 (14): 9266–9271. doi:10.1073/pnas.142033699. PMC 123129. PMID 12089326. 
• Daily, Gretchen C., and Pamela A. Matson (2008). "Ecosystem services: From theory to implementation". Proceedings of the National Academy of Sciences (105): 9455–9456. 

External links

• Damassa, Tom (October 26, 2006). "Human Consumption Pushing Ecosystems to the Brink". EarthTrends Environmental Information. Retrieved March 1, 2009. 
• Friedman, Thomas (2008). Hot, Flat, and Crowded. New York: Farrar, Straus, and Giroux. ISBN 0-374-16685-4. 
• Khanna, Parag (2008). The Second World. New York: Random House. ISBN 81-7036-406-X. 
• "Carbon offset". Carbonfund.org. Retrieved March 1, 2009. 
• Futehally, Ilmas. "Living Beyond Our Means". Strategic Foresight Group. Retrieved December 2008.