Extreme heat adaptation in Tokyo requires shifting from school-level coping to systemic capacity-buildingAs climate change intensifies the urban heat island effect, outdoor school settings are becoming increasingly important for protecting children's health and well-being. Heat waves and other climate-related disruptions to education are becoming more frequent, prompting cities to adopt strategies such as climate-resilient schoolyard design. However, inequities in access to school green infrastructure persist, shaping children's exposure to nature, thermal comfort, and developmental opportunities while reinforcing broader patterns of environmental injustice. Despite growing evidence from Western contexts, these issues remain understudied in densely populated Asian megacities. This study examined how Tokyo’s public elementary schools adapt schoolyards to extreme summer heat amidst spatial constraints due to increasing urbanization and rising student enrollment. The study is the first citywide assessment of Tokyo’s elementary schools to explore how schools mitigate extreme heat. The study employed an environmental justice framework, which views disparities in climate adaptation and heat protection as central equity issues.
Japanese schoolyards are typically flat, unshaded, and designed for multifunctional use, including disaster evacuation, yet climate adaptation measures in their design and infrastructure remain limited. To assess how schoolyards are adapting to intensifying heat, questionnaires were distributed to school administrators (principals or vice-principals) at all 1258 public elementary schools in Tokyo. Most schools were located in Tokyo's densely populated and highly urbanized 23 special wards. Schools from the surrounding Tama and Island regions, which are less densely populated and generally have lower socioeconomic status, were also included. The researchers developed the questionnaire based on a review of the relevant literature and a pretest with five educators. The questionnaire was comprised of 42 items, including multiple-choice questions, Likert-scale items, and open-ended questions, organized into five sections: (1) facility environment and physical characteristics, (2) wet-bulb globe temperature (WBGT) monitoring (a heat-stress index) and heat management protocols, (3) playground usage restrictions related to enrollment, (4) strategies for supporting physical activity, and (5) perceptions of climate change and adaptation needs. Questionnaires were administered after the summer season to glean administrators’ thoughts on their recent heat management practices and institutional decision-making processes. A total of 434 complete questionnaires were received (34.5% response rate), including 275 from schools in the 23 special wards, and 159 from schools in Tama/Island Regions. Multiple-choice questions and Likert-scale responses were scored and statistically analyzed. Open-ended question responses were thematically analyzed, revealing five themes: (1) WBGT implementation discrepancies, (2) infrastructure limitations, (3) educational scheduling conflicts, (4) greening-related burdens, and (5) children’s behavior and health concerns.
Although nearly all schools (99.8%) reported having a schoolyard, significant disparities were documented in the specific spatial features between the two regions. Tama/Island schools reported having more courtyards and green elements such as school farms, shade-creating grove forests, and flower beds. Schools in the 23 wards had significantly more rooftop play spaces. Schoolyard surface materials also differed, with Tama/Island regions using natural surfaces (sand and grass) and the 23 wards incorporating more artificial materials, which tend to retain heat. WBGT was measured in 99% of schools; however, only 27% recorded these results. To prevent heat stroke, schools in the 23 wards restricted outdoor play more frequently. Schools in the 23 wards also reported more spatial constraints and increasing enrollment pressure. Nearly half (45%) of all schools indicated restricting student occupancy in schoolyards during breaks; however, this practice was significantly more common in the 23 wards. School administrators reported that extreme heat regularly impacted educational functions such as outdoor physical education. Administrators also reported conflicting aims between heat safety protocols and educational requirements. Schools used various strategies to mitigate heat-related play restrictions, with differences again identified between regions. Tama/Island schools adapted by opening schoolyards in the morning before classes, and 23-ward schools utilized air-conditioned gymnasiums or brought play materials to classrooms. However, these strategies were often difficult to implement due to staffing limitations. Across both regions, administrators expressed strong concern for climate acceleration and its impact on student safety and behavior during intense heat. Administrators in the 23 wards especially felt that with increasing student enrollment, more restrictions on schoolyard use would be necessary in the future. They also called attention to institutional and budgetary limitations, which made school improvements difficult. Administrator comments also highlighted the need for a fundamental transformation in infrastructure adaptation that extends beyond current risk management approaches centered on behavioral restrictions.
Findings highlight the need to address regional disparities and environmental injustice in heat adaptation. Differences between regional schools reveal an unequal distribution of environmental resources and climate-related burdens. Notably, although Tokyo's urban schools are generally socioeconomically advantaged, they have substantially less natural greenery because of severe land constraints. Further, educational policy has largely overlooked schoolyards as spaces for equitable access to outdoor environmental resources. “Overall, the evidence indicates that effective heat adaptation in schoolyards requires systemic capacity-building for transformative adaptation—dedicated maintenance structures, technical guidance, and cross-sector coordination—rather than reliance on school-level coping strategies alone.” The researchers propose several recommendations to address environmental injustice and strengthen adaptive capacity in Tokyo schools. These include recognizing the ecological and thermal value of schoolyards; transforming them into multifunctional spaces through the implementation of green infrastructure; directing funding toward municipal maintenance infrastructure; integrating schoolyards into broader urban greening and climate adaptation plans; and employing participatory design approaches that include children in decision-making processes.
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