Grey infrastructure often damages or eliminates biophysical processes  necessary to sustain ecosystems, habitats and livelihoods, where urban ecological infrastructure  can be more flexible and cost effective for providing flood risk reduction and other benefits . Hybrid approaches are emerging that integrate ecological and grey  infrastructure in adaptation planning and hazard protection . Explicit policy uptake by city authorities is increasing , such as in New York where in 2010 the city committed to a hybrid infrastructure plan for storm water management, investing USD 5.3 billion over 20 years, of which USD 2.4 billion was targeted for green infrastructure investments . A subset of services from urban ecosystems are being increasingly invested in as NBS for climate adaptation pathways  and included as regulatory drivers through flood management, hazard mitigation and air pollution regulations that encourage or enforce the implementation of green infrastructure practices .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report