Australian: CLIMATE change is so inexact a science that debate over how much, if at all, it is responsible for the crisis in the Murray-Darling Basin will produce little but hot air. While politically inept to open up the debate, Brendan Nelson is correct that water management is one problem we can address immediately. Regardless of whether manmade greenhouse emissions are exacerbating the problem by warming the basin and increasing evaporation, drought has been part of the Australian landscape for …