Thresholds
Related terms: thresholds, engineering, signs, expertise, lines
Thresholds are semiotic devices that help one navigate the world. Perhaps a better-known contraption for reading thresholds is a thermometer, an instrument that can measure the temperature of a solid, liquid, or gas. Even when a thermometer is not readily available, people can gauge temperature. If the wind blows, the ambient temperature may feel chilly, or if a dog’s ears feel warm, its body temperature might run high and amount to a fever. In more basic terms, thresholds help convey meaning about limits or intensity (Kockelman 2022). Rarely do people talk about thresholds in situations wherein the value of things is stable. Instead, thresholds are often invoked in moments of pending change or uncertainty.
The fear of uncontrollable danger helps advance metapragmatic discourses about thresholds. From fad diet regimes that claim to alter human gut microbiomes (s), government efforts to manage anti-terrorism, Motion Picture Association movie ratings, to climate adaptation projects, thresholds are everywhere in the popular zeitgeist. Importantly, one’s awareness of thresholds is not reducible to calculation or to what Ulrich Beck (2008) and others have lamented as the re-distribution of industrial, financial, or algorithmic risks (Chun 2015). There are other ways of knowing thresholds. More intimate methods might involve maintaining a friendship with a telephone call rather than a text message. Or cleaning oneself with bar soap instead of liquid soap.
But the human effort to document thresholds in the historical record might not matter much to the overall appearance of planet Earth. Cycles of erosion along shorelines occurred for millennia well before passenger ships, pollution, sea defences, or housing interrupted them. Likewise, species migrations have considerable effects on the environments left behind and the ones to which these species relocate. The multi-continental movement of woolly mammoths during the shift from the Pleistocene to the Holocene is a case in point. On a radically different scale, the seasonal migration of monarch butterflies across the Northern Hemisphere has made it possible, for lay publics and scientists alike, to account for climate variations (Ethier and Mitchell 2023; Worldwide Wildlife Fund 2025).
Encountering thresholds may at first seem endless. In the most cynical reading, the word ‘threshold’ might stand in as a synonym for cultural relativism. Life on planet Earth – after all is said and done – is not dominated by any singular mode of thought or action. Thresholds are transspecies, geo-ecological, interdisciplinary, posthuman, etc. No one person or entity has a monopoly on thresholds: everyone can claim their threshold or have an interest in staking a piece of someone else’s. This reminds us that thresholds shape the way humans decide (or not) to comingle and get along with other species on Earth. Such decisions about thresholds, however, are not simply an index of cultural identity.
Thresholds also possess an aura to which every person can relate. They are types of marked lines that reflect on conditions of well-being across the past, present, and future. In the essay “Paintings, or Signs and Marks” (2002), Walter Benjamin sought to distinguish a typology of lines. Too often, he mused, “it is customary to regard the graphic arts simply as painting” (82). Instead, he notes that pictures are usually presented vertically while signs – words on the page – are presented horizontally. Vertical and horizontal lines provide a novel entry point into detailing the social energies that compose daily life and the thoughts of people from the past. As Benjamin asserts, “The realm of the sign comprises various territories which are defined by the fact that, within their borders, ‘line’ has various meanings. The possibilities include the geometric line, the written line, the graphic line, and the line of the absolute sign” (85). Yet, he made no commentary on why – or how – people give more credence to some types of lines rather than others. This is the situation the planet now confronts with climate change. Some people can increase or decrease the global average temperature, while others simply see no room to assert such agency. In short, thresholds represent the shifting human capacity to care for the planet.
Thresholds animate the recent calls by the United Nations-Intergovernmental Panel on Climate Change for global action to address climate change. The 2010 Paris Climate Agreement was a landmark treaty that called for limiting global warming to 1.5˚C above preindustrial levels. In turn, the 1.5˚C threshold has come to be understood as a line that ought to guide humanity into the future because of its claim to scientific objectivity. Without a doubt, debates about the Realpolitik of capitalist growth and energy transitions are at stake here. Both proponents and critics of the term ‘climate denial’ have noted that the word ‘threshold’ fails to effectively capture the nuances of contemporary life dictated by unprecedented weather, species loss, and resource depletion (Norgaard 2011; Connolly 2013). At the same time, the alternative to the threshold debates is not altogether clear. Although the global average temperature exceeded 1.5˚C in 2024, the Paris Climate Agreement remains an aspiration of the countries and parties who have remained committed to the treaty. The United States is an example of a country that has backed off. In the meantime, the UN has further broadened its approach to climate action, which entails not only climate mitigation but also more robust measures for financing climate adaptation. In turn, the 1.5˚C threshold has stood in as a helpful moniker for the dual techno-financial reality of what it takes to manage climate change: a re-envisioning of ‘big science and technology’ and the money to do it.
And yet, in much of my research, I have found that finance is not the principal force animating the way people think about climate adaptation and how to make it happen. Understanding this point is a problem of perspective as much as privilege. Places like Guyana and other parts of the Caribbean that I know well have been an afterthought to how much of Euro-American academia has theorised such concepts as ‘thresholds’ in the arena of climate change politics. On the other hand, my book Engineering Vulnerability: In Pursuit of Climate Adaptation (2022) offers an alternative point of view by examining how Guyanese engineers aspire to create a more hospitable planet.
Guyanese engineers have demonstrated competence through the protection of mangrove forests and the restructuring of earthen dams to adapt the country’s coastal plain for long-term settlement. Their efforts have involved confronting the legacies of Dutch and British colonial interventions in water management that demanded the removal of Amerindian communities, Black enslavement and labour, and Asian as well as Portuguese indentured labour. All racial groups were implicated in and contributed to the colonisation of the coastal plain. But Guyana’s legacy of engineering does not end on this point about exploitation, cultural alterity, and dispossession. Seawalls, dams, and canals are national monuments that demonstrate how Guyana is a multiracial democracy on the frontlines of climate adaptation. Imperfect in many ways, the Guyanese nation-state has not only had to confront the inequities of flood management but also recent government efforts to cash in on offshore oil and gas exploration. To this end, Guyanese engineers’ interventions help redefine the 1.5˚C threshold beyond the aims of global treaties.
Their interventions bring into full view the minor histories of tinkering and technological innovation that often go overlooked in both policy and critical academic conversations about the Anthropocene. Rather than assume that technoscience is the signature domain of the global North, Guyanese engineers work tirelessly to refine hydraulic models and infrastructural designs to suit their needs. What their efforts demonstrate is that even tools of oppression can be reimagined to offer ways of living that are more inclusive. Guyanese engineers are not just technocrats; they are people who come from all walks of life. I know of engineers who racially identify as Black or Indigenous and who were born into a life of luxury, while others have found their way into the profession with the ambition to achieve economic stability and security. Some even have family or ancestral backgrounds in subsistence farming or adhere to religious beliefs that influence the way they care for waterways, soils, plants, and the people inhabiting land next to massive infrastructural projects.
Beyond the image of a warming planet, thus, thresholds extend far and wide into questions about expertise and who can claim it. From large-scale damming to reconsidering the very technologies, such as the steam engine, that have made climate change the problem we know today, climate adaptation in the Caribbean is happening. The question is who is paying attention, and if they are not, why is that the case? Thresholds bring to the fore such questions that make ‘business as usual’ no longer sustainable, both in the politics of climate change and the academic documentation of it.
References
Beck, Ulrich. 2008. World at Risk. New York: Polity.
Benjamin, Walter. 2002. Painting, or Signs and Marks. In Selected Writings 1: 1913–1926, ed. H. Eiland and M. Jennings. Cambridge, MA: Harvard University Press.
Chun, Wendy Hui Kyong. 2015. “On Hypo-Real Models or Global Climate Change: A Challenge for the Humanities.” Critical Inquiry 41(Spring): 675-703.
Connolly, William. 2013. The Fragility of Things: Self-Organizing Processes, Neoliberal Fantasies, and Democratic Activism. Durham: Duke University Press.
Ethier, Danielle M. and Greg W. Mitchelle. 2023. “Effects of Climate on Fall Migration Phenology of Monarch Butterflies Departing the Northeast Breeding Grounds in Canada.” Global Change Biology 29(8): 2122-2131.
Kockelman, Paul. 2022. The Anthropology of Intensity: Language, Culture, and Environment. Cambridge: Cambridge University Press.
Norgaard, Kari Marie. 2011. Living in Denial: Climate Change, Emotions, and Everyday Life. Cambridge: MIT Press.
Vaughn, Sarah E. 2022. Engineering Vulnerability: In Pursuit of Climate Adaptation. Durham: Duke University Press.
World Wildlife Organization. 2025. “Monarch Butterflies and Climate Change.” .