The integration of Geodesign into territorial planning highlights the importance of co-creation processes that consider local values, traditions, vulnerabilities, and potentialities. A successful planning intervention depends not only on technical accuracy but also on the planner’s ability to translate spatial readings into proposals that resonate with citizens’ expectations. This principle guided the Brazilian team’s participation in the IGC 2023/2024 – Global Carbon Geodesign Challenge (GC2), through case studies conducted on Florianópolis Island (Santa Catarina) and in the Iron Quadrangle (Minas Gerais). In both territories, WebGIS platforms were developed using the GisColab system by GE21 Geotecnologias, providing an interactive Spatial Data Infrastructure (SDI) with thematic maps that enabled visual analysis and supported participatory engagement. Central to the process were simulations comparing current land use with projections for 2050, stimulating shared awareness and motivating collaborative planning. Each workshop spanned four sessions (16 h total), beginning with an introduction to the GC2 project and an Enrichment of Reading activity based on the map collection. While initial inputs were pre-defined, participants later proposed additional themes to tailor the spatial analysis. Proposal development followed the framework of climate action domains: inland water, urban, energy, transport, forest, agriculture, and either ocean (Florianópolis) or industry (Iron Quadrangle). The use of scenario-based simulations proved essential to enhance understanding of future landscape implications and foster meaningful public involvement, reinforcing the value of participatory Geodesign in territorial planning practices.