Using an age-grouped Gaussian-based two-step floating catchment area method (AG2SFCA) to measure walking accessibility to urban parks: With an explicit focus on elderly

Rapid population aging has raised the number of elderly residents dramatically, calling out the challenge to provide elders with sufficient and equal urban park spaces in cities with limited land use. Ensuring elders have matched accessibility to urban parks is essential for social sustainability. This study introduces an age-grouped Gaussian-based two-step floating catchment area method (AG2SFCA) to more accurately reflect the urban park accessibility of the elderly and to explore the influence of population aging on residents' accessibility evolution. The applicability and rationality of AG2SFCA are demonstrated through the case study in the Chengdu city center. The results indicate that most elders' urban park accessibility and overall horizontal equity level are overestimated in the previous adjuted 2SFCA approach. There is no unified relationship between residents' accessibility and the population aging condition in their community. However, residents' accessibility is related to the overall aging level of society. Even in the urban core of Chengdu, many elders still have no access to urban parks. The high proximity can help elders maintain their matched accessibility to urban parks despite an aging population. This study enriches the application of 2SFCA-style models and helps provide empirical support to governments, urban planners, and facility operators for targeted decision-making.