A technologist visits sustainability

There was a time, not in too distant past, when Microsoft Word would not recognize the word ‘‘sustainability’’ in a text. Since then authors from all walks of life have written numerous narratives on sustainability or sustainable development. The United Nations and most governments on the planet have come together to promote sustainable development globally and nationally. Industry, especially large multinational corporations, have created their own organizations to promote sustainability. Local governments in every corner of the world are proponents of sustainability with programs titled ‘‘sustainable this’’ or ‘‘green that’’ to implement it. A responsible citizen dutifully separates recyclables from household wastes. Another drives a hybrid or an electric car. Yet another citizen volunteers for a citizen action group to promote solar or wind power. Are these behaviors contributing to sustainability? There can be two short answers, of which the first is: Perhaps. The second answer: We really would not be able to tell without knowing what the other interacting agents in society naturally do. The economy and society are vastly more complex than the simple causal relationship that we use such as ‘‘if we do this, that happens.’’ Profound confusions remain at every level of society about what one is supposed to do about sustainability. From the point of view of the science and engineering research, here is an attempt to make some sense on how this research community might look at sustainability. The word ‘‘sustainability’’ nowadays is as frequently used to connote its common sense meaning as to reflect the sense that came from the global environmental movement, generally accepted to have been popularized by the Bruntland commission report, our common future, of the UN-sponsored world commission on environment and development (WCED). No science dictionary has a useful scientific definition of the term. This is not surprising. Even though sustainability has penetrated many fields of science and engineering, the understanding varies from person to person, discipline to discipline. In truth, this is a sociopolitical idea, not a scientific one. Prof. J. Pop-Jordanov of Macedonia has compiled the distinctive ideas that are central to different professions in this context. For instance, for an economist, quantifying the environmental ‘‘externalities’’ is central to assessing human welfare. An ecologist is focused on studying the ways the carrying and regenerative capacities of natural resources are impaired by human enterprise. To a physicist, sustainability is ‘‘the ability of biological systems to fight against degradation of energy and resources (entropy) by creating new forms of order (negentropy) using the various inputs of solar energy.’’ To a chemist or an engineer, however, it is ‘‘the challenge to complete material and energy life cycles created by human activities, through new techniques for material design, re-use, recycling and waste management.’’ Though these disciplinary foci can be highly technical, none of them captures the sociopolitical definition given by the Bruntland commission report: ‘‘Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs.’’ This report is human centric, and its emphasis of intraand inter-generational equity is clear. It cried out for an unspecified plan of action to reverse widespread environmental damage to our planet by human activities, depleting finite natural resources in the process, and creating a huge gulf between ‘‘Haves’’ and ‘‘Have Nots’’. Our common future did not define sustainability per S. Sikdar (&) National Risk Management Research Laboratory, U.S. Environmental Protection Agency, Cincinnati, OH, USA e-mail: sikdar.subhas@epa.gov