TS.D.5.2 The projected future effectiveness of available adaptation for agriculture and food systems decreases with increasing warming . Currently known adaptation responses generally perform more effectively at 1.5℃ than at 2ºC or more, with increasing risks remaining after adaptation at higher warming levels . Irrigation expansion will face increasing limits due to water availability beyond 1.5℃ , with a potential doubling of regional risks to irrigation water availability between 2ºC and 4ºC . Negative risks even with adaptation will become greater beyond 2℃ warming in an increasing number of regions .  
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report