thanks to tube well irrigation crops in northwest india are less vulnerable to drought than other regions ensuring them the lowest interannual production variability kawashima however the actual pace of groundwater depletion threatens the sustainability of this system if punjab had no access to irrigation the maximum attainable yield for wheat would fall by half compared to the current local yield and by more than two thirds for rice bruinsma a collapse of the groundwater irrigation system would be all the more dramatic in northwest india since rainfed crops are particularly exposed to climate change in this region