In past decades, a number of categories of adaptation options have been identified and are discussed in Section 8.5. Adaptation options are categorised in various ways, such as in terms of grey and green adaptation or hard and soft measures . Grey measures refer, for example, to technological and engineering solutions to improve adaptation of infrastructures or to protect a specific land use or city from adverse consequences of climate hazards . Accordingly, ecosystem-based approaches, including natural infrastructure, can provide an effective complement or substitute for traditional built  infrastructure. For example, watershed restoration can protect sources of drinking water and reduce the need for subsequent treatment. Green measures often encompass ecosystem-based  approaches. These make use of the multiple services provided by ecosystems to improve resilience and adaptive capacity or to reduce risk. Soft adaptation measures include policy, legal, social, management and financial measures that can alter human behaviour and support adaptive governance, contributing to improved adaptation capacity, increased awareness, and change in values and actions on climate change issues.
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report