Green Spaces in South Korea Buffer Negative Emotions, Study Finds

Green spaces have long been celebrated as mood boosters, but a new study from South Korea suggests their quiet power lies somewhere unexpected: not in making people happier, but in making them less sad, anxious, and angry. In an era when cities worldwide are rethinking how vegetation fits into public health policy, the findings offer a sharper, more nuanced picture of what green environments actually do for our emotional lives—and what they do not.

The research, published in the journal Applied Research in Quality of Life, set out to answer a deceptively simple question: does living amid denser vegetation shape how people feel? To find out, a team led by Yookyung Lee of the Yongin Research Institute, together with Changhyun Jun, Hyochan Kim, and Jongjin Baik of Korea University and Seungwoo Han of Kyonggi University, combined two very different kinds of data. On one side was satellite imagery, used to calculate district-level vegetation density across South Korea. On the other were individual-level responses from a nationally representative happiness survey conducted by the National Assembly Futures Institute, which captured how residents actually felt during one of the most emotionally demanding periods in recent history: the COVID-19 pandemic.

The choice of study period was deliberate. Pandemic lockdowns and social distancing measures created a natural experiment of sorts, subjecting entire populations to collective stress while leaving people in widely varying environmental circumstances. Some South Koreans spent months surrounded by forested hills and leafy neighborhoods; others contended with dense, gray urban districts. If green environments genuinely buffer emotional strain, the pandemic offered an ideal moment to detect that effect. Periods of widespread psychological pressure, the researchers reasoned, raise fundamental questions about how everyday surroundings relate to emotional well-being—questions that are harder to answer in calmer times when the influence of environment may be drowned out by routine.

Technically, the study hinged on satellite-derived vegetation measures, an approach common in environmental epidemiology but rarely married so carefully to affect-based psychological outcomes. Rather than relying on residents’ subjective impressions of how green their neighborhood was, the team used objective remote sensing data, capturing the actual presence and density of vegetation across administrative districts. This matters because perceived greenness can be contaminated by the very moods under study: people who feel depressed may literally see their surroundings as bleaker. Grounding the exposure measure in satellite imagery sidesteps that circularity, allowing the researchers to ask whether physical vegetation—an environmental fact independent of perception—tracks with emotional experience.

The emotional outcomes were equally carefully parsed. Following guidelines established by the Organisation for Economic Co-operation and Development for measuring subjective well-being, the analysis distinguished between positive affect—feelings such as joy, contentment, and cheerfulness—and negative affect, which encompasses anxiety, sadness, anger, and similar distressing states. This distinction proved to be the study’s most consequential methodological decision. Much popular discourse treats happiness as a single dial that greenery turns upward. The two-dimensional framework allowed the researchers to test that assumption directly rather than take it for granted.

The results were strikingly asymmetric. Vegetation density, the researchers found, was not consistently associated with positive affect. People living in greener districts were not reliably more joyful, more cheerful, or more content than those in sparser surroundings. But when the team turned to negative affect, a robust pattern emerged: higher levels of vegetation were strongly associated with lower levels of negative emotions, and this held true both at the district level, comparing neighborhoods with one another, and at the individual level, comparing survey respondents across the country. In other words, greenness appeared to function less as a source of positive emotion and more as a shield against negative ones.

That asymmetry carries real theoretical weight. Psychologists have increasingly argued that positive and negative affect are not opposite ends of a single scale but partially independent dimensions of emotional life, each with its own correlates and consequences. The new findings align with a body of work suggesting that negative emotions are especially predictive of psychological health and adjustment, and that the ability to dampen them—rather than the ability to amplify positive ones—may be central to emotional resilience. Against this backdrop, the study’s conclusion that the emotional relevance of green environments may lie primarily in their association with reduced negative affect reframes what urban greenery is actually for. It is less a happiness engine than a stress buffer.

The mechanism, though not directly tested in this study, plausibly connects to decades of research on nature and the human mind. Attention restoration theory holds that natural environments engage the mind in an effortless, involuntary way that allows depleted attentional resources to recover, and systematic reviews have supported the restorative potential of nature exposure. Complementary work in neuroscience has shown that viewing green urban landscapes modulates activity in brain regions tied to stress responses, while physiological studies have linked green space exposure to lower cortisol levels in deprived urban communities. There is also evidence that even small amounts of greenery can reduce stress, and that vertical greenery can buffer psychophysiological stress responses in virtual reality experiments. A stress-buffering account fits neatly with the new finding that vegetation suppresses negative affect: if green environments calm the stress machinery of the brain and body, their most visible emotional signature would be fewer bad feelings rather than more good ones.

The pandemic context strengthens the practical stakes. Numerous studies have documented that green spaces became lifelines during COVID-19 lockdowns, with changes in green space use tracking individual and environmental characteristics, and with green space accessibility helping to buffer declines in mental health documented in large-scale data from the United Kingdom. Research from around the world—including analyses spanning eighteen countries and regression discontinuity studies conducted during shifts in COVID containment policy—has converged on the conclusion that proximity to greenery matters most when psychological strain is highest. The South Korean study adds an important refinement to this literature: the benefit may be concentrated specifically in the negative-affect channel, which is precisely the channel most stressed during a collective crisis.

South Korea makes an instructive setting for this inquiry. The country is one of the world’s most rapidly urbanized societies, with a large share of its population concentrated in the Seoul metropolitan area, where housing pressure and spatial stratification are well documented. At the same time, much of the country remains heavily forested, producing sharp contrasts in vegetation density across districts even within short distances. That variation gives satellite-based vegetation measures real analytical leverage. The pandemic, meanwhile, hit South Korea early and prompted aggressive containment measures, making the period a genuine test of how environments relate to emotion under sustained, population-wide stress.

The study is not without limitations, and the authors are careful about causal language. The design links vegetation density to reported affect at a single point in a stressful period; it cannot fully rule out the possibility that greener districts differ from sparser ones in other ways—income, housing quality, age structure, or access to services—that independently shape emotional well-being. Wealthier neighborhoods often have more trees, and wealth buys many buffers against negative emotion. The researchers addressed confounding through their statistical controls and by testing associations at both district and individual scales, but the findings are best read as robust correlational evidence rather than proof of causation. Still, the consistency of the negative-affect association across two levels of analysis, in a nationally representative sample, during a period of exceptional stress, gives the result unusual credibility.

For urban planners and public health officials, the implications are concrete. If the value of green infrastructure lies chiefly in damping negative affect, then planting and preserving vegetation is not merely an aesthetic amenity or a property-value strategy—it is an emotional-health intervention, most valuable precisely where and when distress is concentrated. This aligns with a growing body of work on green space and health equity, which finds that greenery has the potential to reduce health disparities, and with research showing that even modest greening can yield measurable psychological benefits. The findings also suggest that evaluations of green infrastructure projects should measure negative affect—stress, anxiety, anger—alongside conventional happiness and life-satisfaction metrics, or risk missing the benefit that matters most.

The study points toward future research directions as well. Disentangling which types of vegetation matter most, whether street trees differ from parks, how greenness interacts with walkability and access, and whether the negative-affect buffering effect generalizes across cultures and climates are all open questions. Longitudinal designs that follow individuals as they move between greener and sparser environments would help establish causation. And with the underlying data for this study publicly available through Harvard Dataverse, other researchers can scrutinize, replicate, and extend the analysis.

What emerges most clearly is a reframing of an old idea. The popular imagination casts nature as a fountain of happiness; the scientific evidence increasingly paints it as something more subtle and, arguably, more valuable—a quiet regulator of distress. In South Korea during the pandemic, the people surrounded by denser vegetation were not measurably happier, but they were measurably less burdened by negative emotion. In a world facing climate stress, urbanization, and recurring collective crises, that may be exactly the kind of resilience worth planting.