If sustainability is to be our focus, it seems we have some issues to resolve on exactly what it is we are focusing on. In my efforts to better understand the concept, I came across an interesting article that gets at some of the challenges associated with trying to figure out what sustainability really means, and once we agree on a meaning, how we go about achieving it.
The article is titled FRAMING THE ELUSIVE CONCEPT OF SUSTAINABILITY: A SUSTAINABLE HIERARCHY and was written by Julian D. Marshall and Michael W. Toffel in Volume 39, Number 3 of ENVIRONMENTAL SCIENCE & TECHNOLOGY.
The authors begin their paper with an introduction that explores some of the history of the use of the term sustainability as related to the environment. They point out that:
By the mid-1990s, there were well over 100 definitions of sustainability. This definitional chaos has nearly rendered the term sustainability meaningless and is distracting from the need to address ongoing environmental degradation.
They provide a brief overview of four sustainability frameworks that include:
The Triple Bottom Line. Advocates of “the triple bottom line” believe that organizations pursuing sustainability ought to make decisions based not only on economic returns but also on environmental protection and social justice.
The Natural Step. The Natural Step defines a sustainable society as one where four conditions are met: “nature is not subject to systematically increasing (1) concentrations of substances extracted from the earth’s crust, (2) concentrations of substances produced by society, or (3) degradation by physical means; and, in that society, (4) human needs are met worldwide”.
The Ecological Footprint. The Ecological Footprint compares the environmental impact of specific actions to the limitations of the earth’s natural resources and ecosystem functionality.
Graedel and Klee’s Sustainable Emissions and Resource Usage. Graedel and Klee propose a four-step process for determining a sustainable rate of resource use: (i) calculate the available supply of virgin materials (mass); (ii) allocate consumption of this supply over a specific time scale and among the global population (mass per person per year); (iii) account for recycling and for existing stockpiles including landfills and then update the allocated consumption rate; and (iv) consider this rate to be the maximum sustainable consumption rate and compare it to the current usage rate.
The authors then propose the use of a Sustainability Hierarchy, much like Maslow’s “Hierarchy of Needs” that lays out ways of categorizing actions into four levels to determine whether or not they are sustainable.
Level 1: Actions that, if continued at the current or forecasted rate, endanger the survival of humans.
Level 2: Actions that significantly reduce life expectancy or other basic health indicators.
Level 3: Actions that may cause species extinction or that violate human rights.
Level 4: Actions that reduce quality of life or are inconsistent with other values, beliefs, or aesthetic preferences.
The four levels make it clear “that an action can be considered sustainable on one level, while unsustainable at another” and that there is a need to specify which level is being considered when an action is labeled as “sustainable” or “unsustainable”.
The importance of considering the ecosystem when it comes to sustainability decision making is highlighted where the authors point out that ”ecosystem function refers to the goods and services provided by the natural environment that are required to support human life, human health, and species viability. Changes in ecosystem function can indicate changes in the health of the ecosystem.” They also speak about the importance of including consumption in the sustainability equation when they remind us that: “Consuming resources beyond regenerative rates can impede ecosystem function and eventually lead to ecosystem collapse.”
And they also include what I believe is the key measure of sustainability – “Actions that impair ecosystem function too much are unsustainable, while those that maintain ecosystem function are sustainable.” This line reminds me of Aldo Leopold’s classic land ethic summary “A thing is right when it tends to preserve the integrity, stability, and beauty of the biotic community. It is wrong when it tends otherwise”
The authors conclude that
“sustainability means transforming our ways of living to maximize the chances that environmental and social conditions will indefinitely support human security, wellbeing, and health”. Indeed, this offers a useful working definition for “sustainability”. While improving the health, security, and quality of life for humans is an ethical imperative, the morally desirable level of improvement extends beyond that which is required for human survival, health, or human rights. As such, to preserve meaning in the term sustainability, people must be explicit about the hierarchy level to which they are referring and be cognizant of the term’s spatial and temporal dimensions. As discussed above, we discourage those addressing level 4 issues from labeling their work - worthy as it is - as sustainability. We also discourage the use of sustainability as a synonym for “good” or for “having a reduced environmental impact”.
Although I understand why the authors recommend leaving level 4 issues out of the sustainability category, namely because of the difficulty that dealing with issues from this highest level bring with them, failure to reach for this higher level will not in the end result in any kind of long-term sustainable society. It is the higher level actions that are what make us human - that ultimately sustain us. And that is why we need to delve into what sustainability means to us and our work.
There is an acute need for scientists and engineers to incorporate sustainability concerns in their work, such as by exploring the full social and environmental impacts of technologies and technical systems. While tools such as pollution prevention and industrial ecology are useful, “alone [they] are not sufficient to achieve sustainability, because even systems with efficient material and energy use can overwhelm the carrying capacity of a region or lead to other socially unacceptable outcomes”.
And let us not become overwhelmed ourselves.