Future "local climate zone" spatial change simulation in Greater Bay Area under the shared socioeconomic pathways and ecological control line

Scenario-based land use/land cover change (LUCC) simulation can explore different possibilities in the future for decision-making on city development. However, the current LUCC research in urban-rural areas still lacks support for local climate change research due to unmatched scenario settings and simplified land coverage classification. We thus adopt the local climate zone (LCZ) scheme, which includes more detailed 18 land types, to explore future LUCC in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) under the latest Intergovernmental Panel on Climate Change (IPCC) scenario, the shared socioeconomic pathways (SSPs), with different policy constraints. First, we produce a 100-m spatial resolution LCZ map of the GBA in 2020, which achieves an accuracy with Kappa = 0.876. Then, we carry out an LCZ simulation by adopting the Global Change Analysis Model (GCAM) and Future Land Use Simulation Model (FLUS) from 2020 to 2100 under the SSPs. The results show that LCZ projections appropriately reflect different land responses under different SPPs and the contrastive LCZ spatial changes among different cities even under the same scenario. Ecological protection is a crucial goal in the development plan of the Chinese government. Thus, we add the ecological control lines to protect ecological land under SSPs. This protection is pronouncedly reflected in ecological land within built-up areas in central cities and ecological land around urban areas in fringe cities. This study is the first test of LCZ projection under SSPs. The study findings could serve as an application potential for urban planning, urban climate and mega-city studies globally.