This study examined how neighborhood park characteristics condition the mental health impacts of climate stress across 239 South Korean districts from 2021 to 2023 using spatial error models and Johnson–Neyman continuous interaction analysis. The an...
This study examined how neighborhood park characteristics condition the mental health impacts of climate stress across 239 South Korean districts from 2021 to 2023 using spatial error models and Johnson–Neyman continuous interaction analysis. The analysis identified 129 statistically significant park–climate–mental health interactions across four mental health outcomes (sleep disorder prevalence, depression experience rate, perceived stress rate, suicide mortality). All four mental health indicators displayed mixed patterns of park–weather interactions, with buffering-supportive (BS), buffering-worsening (BW), enhancing-supportive (ES), and enhancing-worsening (EW) effects coexisting. This heterogeneity reflects genuine contextual variation rather than measurement error, and focusing on statistically well-calibrated and interpretable BS patterns revealed consistent evidence that park accessibility emerges as the dominant modifier of park–mental health associations across outcomes and meteorological contexts. Tropical nights and rainfall, rather than daytime heatwave days, were the climatic stressors most frequently associated with significant park–mental health interactions, particularly for sleep disorders and depression. Effects were geographically heterogeneous: in less-urbanized districts, park accessibility showed large protective buffering for sleep disorders under heatwave exposure (effects of 4,600–4,830 per category), whereas in highly urbanized districts, park effects were 90% smaller (490.29), suggesting that compressed urban geographies limit the magnitude of park–weather moderation. Park effects on suicide mortality displayed an inverted urbanization gradient, with larger protective buffering in high-urban contexts, indicating that green infrastructure may serve as a critical social buffer in dense metropolitan settings facing elevated suicide risk. Findings indicate that neighborhood parks do not exert a single, stable protective effect nationwide, but instead function as context-dependent buffers whose magnitude and direction depend fundamentally on accessibility, vegetation quality, meteorological conditions, and urban form. Results support an accessibility-first climate adaptation strategy: rather than expanding total park area uniformly, policies should prioritize walkable access to neighborhood parks in climatically vulnerable regions, combined with place-based design (shade trees and water features in high-nocturnal-heat areas; permeable paths and covered spaces in high-rainfall regions) tailored to local climate and health profiles.