Green Infrastructure as Critical Capital in the Anthropocene

Human societies are confronting converging pressures from climate instability, biodiversity loss, and rapid urbanization that are particularly severe in tropical and subtropical regions. Heatwaves, erratic rainfall, and landscape degradation increasingly expose the limitations of ageing concrete‐and‐steel grey infrastructure, which were designed for climates that no longer exist. This Viewpoint article synthesizes economic valuations and benefit-cost analyses to demonstrate that tropical ecosystems, such as mangroves, forests, and urban greening, function as high-performing critical green infrastructure. When deployed in the right contexts, these living systems frequently outperform or complement grey infrastructure by offering cost‐effective, flexible, and climate‐resilient services.,Drawing on case studies from the Global South, we show that investments in green infrastructure secure substantial economic and societal benefits. Mangrove restoration delivers equivalent coastal protection at two to five times lower cost. Forest conservation in watersheds reduces expenditure on water treatment and dredging. Urban greening reduces mortality and energy demand compared with grey infrastructure. Yet despite strong macroeconomic rationale, including potentially reducing regional GDP by up to 9.7% in Sub‐Saharan Africa and 6.5% in South Asia by 2030, investment remains limited.,We argue that integrating green infrastructure into national development and macroeconomic planning is both an environmental and economic imperative. Recognizing these ecosystems as critical capital and increasing investment in them across the Global South can reduce climate‐related losses, improve resilience, and deliver substantial co‐benefits across societies already on the front line of Anthropocene risks.