In This Issue
Spring Bridge Issue on Engineering and Climate Change
March 15, 2020 Volume 50 Issue 1
The seven articles in this issue cannot cover all engineering-related aspects of climate change, but they highlight several areas of concern.

Engineering and Ethics in the Anthropocene

Monday, March 16, 2020

Author: Elke U. Weber

Climate change, a statistical and increasingly physically evident reality, is a global phenomenon that intersects with the discipline and practice of engineering in important ways, as documented by the articles in this issue. It is not a new phenomenon, but has struggled for the attention of the public, professionals and their organizations, and politicians and policymakers, for a long list of reasons that are psychological, economic, evolutionary, and political (Weber 2015, 2016, 2017).


The French scientist Jean-Baptiste Fourier (1824) first described the physical mechanisms of the greenhouse effect that gives rise to climate change in the early 19th century. In 1861 John Tyndall at the Royal Institute in London determined which gases in the atmosphere trap heat and calculated expected increases in global temperature with surprising accuracy.

More recent prescient observers include the late geochemist Wally Broecker, who in 1975 warned about a planetary crisis if humans continued to emit large amounts of carbon dioxide into the atmosphere. And in 1987 NASA scientist Jim Hansen testified on climate change before Congress.

Engineering as a discipline and profession will be affected by the physical, ecological, social, and political impacts associated with climate change and the response to it (or lack thereof). It has a stake in the current technoeconomic energy infrastructure and in any energy transition toward decarbonization. This includes existing possibilities in oil and gas exploration as well as future jobs and other engineering opportunities in renewables and abatement technologies.

Ethical and Related Considerations

Engineering advances are integral to the detection of climate change (Parkinson 2020). From rain gauges to weather radars and satellites, engineers provide tools to increase the predictability of water resources crucial to human well-being (Lettenmaier and Lund 2020; Sorooshian et al. 2020). Engineers also apply science and engineering principles to design solutions that help people thrive under changing local conditions, from engineering roads, buildings, and pipelines on impermanent Arctic permafrost to adapting to a melting tundra (Schnabel et al. 2020).

It is important to bear in mind that engineering advances in general tend to interact with sociological and psychological considerations and processes. In the engineering psychology class I teach I use signal detection theory, developed by both engineers (Peterson et al. 1954) and psychologists (Tanner and Swets 1954) after World War II, to make this point.

The ability to distinguish a signal/target from background noise in uncertain information environments depends not only on the quality of the engineered physical detection device (e.g., the d-prime of the radar system being used) but also on the motivations of the observer (e.g., a desire to avoid either misses or false alarms and thus the selection of a criterion for identifying a stimulus as either a signal or noise). This suggests that engineers could benefit from being more aware of the users as well as the economic and social impacts of their innovations. Portfolio-based water management that aims to align management options with the behaviors of water users, system managers, and regulators (Lettenmaier and Lund 2020) is a promising example of such an approach.

Responses to climate change raise a plethora of ethical questions, increasingly considered by institutions such as the UN Intergovernmental Panel on Climate Change (IPCC) in their evaluations of response options (Kolstad et al. 2014). Many options concern distributional issues related to the impacts of climate change and/or the costs of adapting to or mitigating it.

Impacts and the ability to afford the costs of action differ between the developed and developing world and between rich and poor communities in all countries. Such equity considerations are raised by Hinkel and Nicholls (2020) in the context of adaptation to sea level rise, but they pervade every aspect of climate change impacts and action.

One important ethical debate, often masquerading as an economic one by posing it as a question about the appropriate discount rate, concerns governments’ and other organizations’ willingness to take responsibility for tackling climate change now versus passing it on to future generations (see Stern 2006 and Nordhaus 2007 for contrasting views on this).

Philosophy and ethics also comment on the role of skepticism to keep the science of climate change honest (Keira 2015) rather than as a tool of vested interests that fight policies designed to increase public welfare (Hoggan 2010).

Limitations of Technological Innovation

One reason climate change is a wicked problem (-Grundman 2016) is that mitigation and adaptation require coordinated action on multiple fronts. Technological innovation—the domain of engineering—is one such front and a necessary ingredient for the majority of the 15 climate stabilization “wedge” strategies described by Pacala and Socolow (2004) to keep CO2 concentrations under 500 ppm for the next 50 years. But it is only one front, and must be coordinated with political action, social innovation, and action by individuals, communities, institutions, and firms.

Simply put, there is no silver bullet—only silver buckshot (Lettenmaier and Lund 2020; Weber and Bell 2014), requiring sustained and integrated action over time. Unfortunately, even professional decision makers typically stop looking for solutions to a problem after one has been implemented—the so-called “single action bias” documented among doctors and farmers (Weber 2015).

Engineering solutions help to reduce energy intensity, increase energy efficiency, and create renewable sources of energy that are cost effective and safe. But such innovation will not suffice. Rapid Switch, a project headquartered at Princeton’s Andlinger Center for Energy and the Environment with partners across the globe, addresses the unprecedented need for both speed and scale in the technological and socioeconomic changes required to confront the climate crisis.

It is becoming increasingly obvious that the silver buckshot needed for speed and scale will involve engineering and institutional innovation in negative emissions technology, parts of which are known as carbon capture and storage, discussed by Wilcox (2020). All but one of the IPCC (2018) scenarios that may restrict average global temperature increases by 2100 to 1.5°C or 2°C require substantial use of this technology. This makes it all the more surprising how little attention and money are allocated to R&D on these technologies, exemplifying perhaps a collective ambivalence to them. On the one hand, climate mitigation experts and modelers argue that these technologies will be needed soon and at major scale and that they do not preclude decarboniza-tion efforts but must operate in parallel to them. On the other hand, to many other segments of society, negative emissions technologies present a moral hazard by appearing to encourage the “wrong” thing, continued use of fossil fuels (Anderson and Peters 2016).

The idea of purchases of carbon offsets elicits the same ambivalent response. Carbon offsets are a very effective way of creating and paying for CO2 sinks as long as properties such as “additionality” and lack of “leakage” are guaranteed (Palmer 2016), but they evoke the medieval indulgences sold by the Catholic Church, absolving sinners for a price. Thus, while proponents view high-quality offsets as an asset that supports carbon-fighting projects, critics see them as a license to pollute.

Principled versus Pragmatic Stances

Ambivalence about negative emissions technologies and carbon offsets raises questions about the pros and cons of either taking a principled and often moral stance on such issues versus being pragmatic and open to technological-social-political-economic solutions that work but may trade off on one value to satisfy another. Multiple goals that are often in partial conflict are a fact of life.

A principled stance introduces a hierarchy into a goal structure and refuses to make certain “taboo” trade-offs between goals (e.g., no price on human life, no use of nuclear power under any circumstances). A pragmatic stance looks for compromises and trade-offs to achieve something like the greatest good across goals.

People and groups differ in their goals, and agreements and solutions need to be found in either cooperative or competitive contexts. Negotiation theory teaches ways to find win-win solutions in such situations, and requires a willingness to creatively explore goal conflict and for each side to compromise on objectives less important to them to achieve gains on objectives of greater importance.

A dogmatic approach may be counterproductive by taking response options prematurely off the table, but standing up for valued principles in an uncompromising way can create sorely needed social counterweights to the all-too-ready sacrifice of societal goals or moral values for short-term profit or expediency.


Discussions of “geoengineering” (e.g., Robock 2020) tend to treat the topic as a concern for the future. No doubt, there are significant issues of unintended consequences and governance to be worked out for technologies like stratospheric solar radiation management. Society needs to determine how best to balance different types of errors of judgment that can be committed in this arena, whether they are errors of commission (“sorcerer’s apprentice” concerns about unforeseen negative consequences) or of omission (failure to aggressively pursue research on risk management strategies that may be necessary in the medium future) (Spranca et al. 1991).

But let me be provocative and state something that should be obvious but is rarely mentioned: It seems rather late to worry about the ethics of engineering the climate now!

Humans have been (inadvertently) engineering current and future climate for multiple decades, as increases in population, industrial output, and other human activity have driven up energy consumption that, satisfied by fossil fuels, has generated rapid increases in greenhouse gas emissions. These effects have earned the current geological age the name “Anthropocene,” to acknowledge the fact that human activity has become a dominant influence on the global climate and environment.

Does it matter that this geoengineering has occurred for the most part without full intention and awareness? Should society not seek and encourage broad-based social dialogue about the ethics of current actions and inactions, especially when asked to do so by growing numbers of its young members around the world? What responsibilities come with humans’ ability to shape the future of planet Earth? What are the potential contributions and/or responsibilities of professional individuals and organizations in this context? One corollary of the silver buckshot reality is that all members and levels of society have a role to play.

Dialogue and Collaboration for the Future

Ten years ago the American Psychological Association convened a task force to determine the contributions that different subdisciplines of psychology can make to establish the impacts of global warming on human mental health, well-being, and decision making and to design better ways to adapt to or mitigate climate change risks (APA 2009). Following my membership on the task force, I engaged in a multiyear scientific collaboration with two engineers and a legal scholar to diagnose and remove barriers to more sustainable infrastructure design by engineers and architects (e.g., Klotz et al. 2018; Shealy et al. 2016). Encouraged by the possibilities, we recently convened an international expert panel that produced a report on the joint contributions of behavioral science, architecture, and engineering toward sustainable design (Klotz et al. 2019).

Similar efforts could enhance awareness of climate change impacts and help determine effective ways of channeling expertise toward climate change solutions in a much broader range of professional disciplines and settings.


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This column is produced in collaboration with the NAE’s Center for Engineering Ethics and Society to bring attention to and prompt thinking about ethical and social dimensions of engineering practice.


About the Author:Elke Weber is the Gerhard R. Andlinger Professor in Energy and the Environment at Princeton University.