Costs of implementing efficient adaptation measures and water- related infrastructure in water-deficient regions have received attention at the global and regional level to bridge the 'adaptation gap' . Livelihood sustainability in the drylands, which cover more than 40% of the land surface area, are home to roughly 2.5 billion people, and support approximately 50% of the livestock and 45% of the food production, is threatened by a complex and inter-related range of social, economic and environmental changes that present significant challenges to rural communities, especially women . Adaptation deficits in arid and semi-arid regions are of high order . To reduce adaptation deficit in arid and semi- arid regions, comprehensive and efficient adaptation interventions integrating better water management, use of non-traditional water sources, changes in reservoir operations, soil ecosystem rejuvenation and enhanced institutional effectiveness are needed  . Communities facing the lack of adequate technological, financial, human and institutional capacities to adapt effectively to current and future climate change often encounter adaptation deficits. To address current adaptation barriers and adaptation deficits, there is a need to promote efficient adaptation measures, coupled with inclusive and adaptive governance involving marginalised groups such as Indigenous communities and women.
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report