The core of the argument rests on a deceptively simple observation. Resilience metrics tell us whether a seawall will hold, whether a hospital has backup generators, and whether a neighborhood has the economic resources to rebuild after a wildfire. What they do not tell us is whether the people inside those systems remain psychologically capable of sustained engagement with a deteriorating environment. Marques contends that this lived, affective dimension is not a soft afterthought but a measurable variable, one that can be captured at the population level and integrated into existing resilience frameworks without replacing any conventional indicator.

To give this emotional dimension analytical structure, the essay introduces the concept of eco-affective state variables: patterned, population-level affective responses that emerge from sustained interactions between people and their environments. These are not fleeting moods or individual diagnoses. Rather, they are stable, trackable states that characterize how entire communities relate emotionally to the places they inhabit. The proposal is that such states can be monitored alongside, and in interaction with, the physical and institutional metrics that resilience science already relies upon, functioning as complementary indicators rather than substitutes.

Two states take center stage in the framework. The first is solastalgia, a term describing the distress caused by unwelcome change to one’s home environment. Unlike homesickness, solastalgia strikes people who have not moved; the place itself has changed beneath them. A farmer watching a familiar landscape turn to dust, a coastal resident watching erosion consume a childhood beach, an urban dweller watching tree canopy vanish block by block, all can experience this distinctive form of loss. The second state is soliphilia, which the essay describes as an affective orientation of care and commitment toward one’s environment. If solastalgia captures the psychological cost of environmental degradation, soliphilia captures the emotional resource that allows people to keep showing up for it.

The pairing is deliberate and analytically significant. Solastalgia and soliphilia are not simply opposites on a single scale; they represent two independent axes of a community’s affective relationship with its surroundings. A population could exhibit high distress and high commitment simultaneously, grieving a changed landscape while remaining determined to protect what remains. Another population might show low distress simply because disconnection has already set in, a scenario that would look deceptively stable on a dashboard but may signal deep disengagement. Reading the two variables together, the essay suggests, offers a far richer diagnostic picture than either alone.

What makes the proposal technically concrete is its specification of three distinct functional roles for eco-affective states within resilience frameworks. First, they can serve as complementary indicators, reported alongside conventional metrics to give a fuller account of community condition. Second, they can act as moderating factors, meaning they influence how other resilience variables behave: a community high in soliphilia may sustain adaptation programs longer than its socio-economic indicators alone would predict, while a community gripped by widespread solastalgia may abandon even well-funded initiatives. Third, and perhaps most provocatively, they can function as early-warning signals, flagging communities under strain before that strain becomes visible in conventional indicators such as migration statistics, economic output, or public health data.

The early-warning function deserves particular attention because it inverts the usual logic of resilience monitoring. Traditional indicators are largely lagging measures: they register damage after it has accumulated, when infrastructure has failed or populations have moved. Affective states, by contrast, may shift early in the trajectory of environmental change, as people perceive and emotionally process degradation long before it registers in hard economic or infrastructural numbers. If population-level solastalgia can be tracked reliably, through validated survey instruments and repeated measurement, it could give planners a lead time that no physical indicator currently provides, allowing interventions to target psychological and social strain before it hardens into displacement or disengagement.

Crucially, the essay draws careful boundaries around what the framework does not claim. Incorporating eco-affective states into resilience quantification, Marques stresses, does not mean pathologizing environmental distress or treating it as a clinical problem to be diagnosed and treated at the individual level. Solastalgia in this framework is a population-level state variable, a signal about the condition of the human-environment relationship, not a mental illness label. This distinction matters both ethically and practically: it keeps the focus on the environmental changes driving the distress rather than on the people experiencing it, and it avoids the medicalization of what are fundamentally rational responses to a changing world. It also means the variables can be integrated into planning and public health systems without requiring clinical infrastructure.

The practical implications extend across several domains that rarely talk to each other. In urban planning, tracking eco-affective states could reveal which neighborhoods are losing their affective attachment to place, information directly relevant to green infrastructure investment and participatory design. In climate adaptation, moderating effects could refine projections of whether communities will sustain adaptation behaviors over the long term, a known weak point in adaptation programs that perform well in pilot phases and fade afterward. In environmental public health, solastalgia monitoring could identify populations under psychological strain linked to environmental degradation, opening a preventive avenue that conventional epidemiological surveillance does not currently capture. In each case, the affective data layer supplements rather than replaces the metrics already in use.

The essay’s larger claim is ultimately about what counts as evidence in resilience science. If resilience is the capacity of a system to absorb shocks and continue functioning, and if human commitment is what keeps that capacity alive over decades of gradual environmental change, then a measurement system blind to emotion is measuring an incomplete system. By proposing that solastalgia and soliphilia be quantified as patterned, population-level variables with defined roles as indicators, moderators, and early warnings, the essay offers resilience researchers a concrete path toward what it calls human-centred resilience quantification. Whether the field adopts it may determine how many communities are caught in time, and how many are discovered to have been struggling only after the conventional numbers finally catch up.

Subject of Research: Human-centred resilience quantification using eco-affective state variables such as solastalgia and soliphilia

Article Title: Toward human-centred resilience quantification: The role of eco-affective state variables

Article References: Marques, L. M. (2026). Toward human-centred resilience quantification: The role of eco-affective state variables. PLOS Mental Health, 3(9), e0000700. https://doi.org/10.1371/journal.pmen.0000700

Image Credits: AI Generated

DOI: 10.1371/journal.pmen.0000700

Keywords: resilience, solastalgia, soliphilia, eco-affective states, climate adaptation, environmental psychology, urban planning, public health, PLOS Mental Health, sustainability, disaster preparedness, environmental change