Annual recurrence and period-composite persistence of child–heat priority across six contrasting urban systems
- 1School of Art and Design, Shandong Women’s University
- 2Wellington School of Architecture, Victoria University of Wellington
- 3ZhongQi MaiHe Tianjin, Engineering Design and Research Institute Co., Ltd.
Abstract
Urban heat adaptation requires spatial evidence showing where larger child populations coincide with high surface heat, especially where comparable paediatric health records are unavailable. Single-year hotspot maps cannot determine whether priority areas recur annually, persist across multi-year composites or remain reproducible across thermal products. A harmonised 10-year ecological framework was applied to New York, London, Singapore, Nairobi, São Paulo and Brisbane using annual WorldPop estimates for children aged 0–14 years and Landsat warm-season land-surface temperature on a common 1-km hexagonal grid from 2016 to 2025. Within each city-year, child count and heat anomaly were converted to percentile ranks and combined using an equal-weight geometric mean. Cells at or above the 90th score percentile formed the annual priority set. Three continuous periods defined period-composite trajectories, while annual membership quantified recurrence, consecutive runs, transitions, entries and exits. The panel contained 78,300 grid-year observations across 60 city-years. Annual priority sets contained 23.3–44.8% of eligible children across cities and 3.1–30.9 percentage points more children than heat-only sets. Among 10-year common-panel cells, agreement between period-composite persistence and annual membership in at least 8 years was moderate to strong but incomplete (Jaccard = 0.55–0.71). Landsat and MODIS/Terra thermal ranks were positively associated ( ρ = 0.35–0.86), whereas annual upper-decile overlap was only 0.11–0.38. Child concentration, annual recurrence, period-composite persistence and boundary reproducibility therefore represent distinct planning dimensions. The framework supports first-stage prioritisation and local verification but does not estimate individual health risk or causal effects.
Related
- Microbial community structure and pathogen persistence in tropical drinking water distribution systems: the role of seasonality and treatment
- Soil organic carbon and nitrogen stocks and isotopic signatures under contrasting integrated crop-ivestock systems in sub-humid Zimbabwe
- Soil Protection: A Strategic Priority of the Soil Museum
- Food redistribution: A critical review of an overlooked priority measure against food waste
- Areas of high conservation priority for threatened terrestrial vertebrates are governed by novel ecological conditions
BibTeX
@article{bian2026annual,
title = {{Annual recurrence and period-composite persistence of child–heat priority across six contrasting urban systems}},
author = {Xin Bian and Shufang Sun},
journal = {Frontiers in Public Health},
year = {2026},
month = oct,
doi = {10.3389/fpubh.2026.1984653},
url = {https://www.frontiersin.org/articles/10.3389/fpubh.2026.1984653/full},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Annual recurrence and period-composite persistence of child–heat priority across six contrasting urban systems
AU - Xin Bian
AU - Shufang Sun
PY - 2026
DA - 2026/10/20
JO - Frontiers in Public Health
DO - 10.3389/fpubh.2026.1984653
UR - https://www.frontiersin.org/articles/10.3389/fpubh.2026.1984653/full
AB - Urban heat adaptation requires spatial evidence showing where larger child populations coincide with high surface heat, especially where comparable paediatric health records are unavailable. Single-year hotspot maps cannot determine whether priority areas recur annually, persist across multi-year composites or remain reproducible across thermal products. A harmonised 10-year ecological framework was applied to New York, London, Singapore, Nairobi, São Paulo and Brisbane using annual WorldPop estimates for children aged 0–14 years and Landsat warm-season land-surface temperature on a common 1-km hexagonal grid from 2016 to 2025. Within each city-year, child count and heat anomaly were converted to percentile ranks and combined using an equal-weight geometric mean. Cells at or above the 90th score percentile formed the annual priority set. Three continuous periods defined period-composite trajectories, while annual membership quantified recurrence, consecutive runs, transitions, entries and exits. The panel contained 78,300 grid-year observations across 60 city-years. Annual priority sets contained 23.3–44.8% of eligible children across cities and 3.1–30.9 percentage points more children than heat-only sets. Among 10-year common-panel cells, agreement between period-composite persistence and annual membership in at least 8 years was moderate to strong but incomplete (Jaccard = 0.55–0.71). Landsat and MODIS/Terra thermal ranks were positively associated ( ρ = 0.35–0.86), whereas annual upper-decile overlap was only 0.11–0.38. Child concentration, annual recurrence, period-composite persistence and boundary reproducibility therefore represent distinct planning dimensions. The framework supports first-stage prioritisation and local verification but does not estimate individual health risk or causal effects.
SN - 2296-2565
ER -