MANAGING WATER IN THE MURRAY-DARLING BASIN UNDER A VARIABLE AND CHANGING CLIMATE

摘要

The highly variable climate of the Murray-Darling Basin (MDB) provides significant challenges for water managers. With the advent of climate change and the likelihood of even greater variability and more frequent extreme events, these challenges will be exacerbated.In 2008, the Murray-Darling Basin Authority (MDBA) was tasked with preparing a Basin Plan for the sustainable management of the Murray-Darling's water resources and, in doing so, develop strategies to manage the risks of climate change. The MDBA built upon pre-existing jurisdictional approaches that manage river systems with extreme flow variability and put in place additional measures within an adaptive management framework.The suite of measures to respond to climate change fall into four broad categories; those that refine existing water management arrangements, those that buffer the system from the additional stress of climate change, those that enhance responses to climate change, and those that facilitate adaptation to climate change at a range of timescales.The recent experience with the Millennium Drought (1997-2009), in which governments put in place special water sharing arrangements to support critical human water needs, highlights a looming policy challenge about how reductions in water availability due to climate change could be shared, including between consumptive use and the environment. Considerations include how State Governments respond to reduced water availability in the development of new water resource plans, whether environmental objectives remain feasible and appropriate under climate change, and what the appropriate balance between social, economic and environmental outcomes will be as agricultural communities undergo broader changes in socio-economic circumstances due to climate change.