I have read with interest the various claims that the draft Basin Plan doesn’t take into account climate change. The fact of the matter is, of course, that climate change is factored into the Basin Plan.
Climate scientists are fond of pointing out that it is difficult to see long-term climate change compared to natural variability. This is no more evident than in the Murray-Darling Basin, where there are several different climate zones that are subject to highly seasonal climate patterns as well as huge variability between years. These are the factors that produce the extreme floods and droughts we’ve experienced over the past decade.
However, there is more than enough information about the Murray-Darling Basin to be confident about two key points. The first is that historical management of the Basin has led to the over-allocation of water. The second is that the Basin’s climate will continue to be highly variable.
The draft Murray-Darling Basin Plan addresses these two key challenges. It establishes sustainable limits to water extraction and returns water to the environment to restore the health of the Basin. This will increase the long-term resilience of the system, allowing the rivers, wetlands and floodplains to adapt to a changing climate. The plan is also based on an adaptive management framework and new ‘whole-of-basin’ arrangements that allow flexible responses to new information about our changing climate.
Water management in the Murray-Darling Basin will always be a hostage to climate. An adaptive management approach is the only way in which we can manage for an uncertain future. This allows for better understanding of future risks, new knowledge, opportunities for innovation, and draws on the ideas and local knowledge of people all across the basin.
The draft Basin Plan has been developed to manage the water resources of the Basin, taking into account all the variability that has been experienced over the last 114 years. The floods of the past two years sit well within this variability.
The better we can be at managing our water resources to deal with the current variability in our climate, the better able we’ll be to adapt to future climate conditions.
Over the past 5 years, the MDBA has collaborated with the CSIRO, the Bureau of Meteorology, the Department of Climate Change and Energy Efficiency and the Victorian Department of Sustainability and Environment to establish the South Eastern Australian Climate Initiative, or SEACI. SEACI has produced 15 climate projections that extend out to 2030.
While we don’t know which of these is likely to eventuate, the range of climate projections has had a major influence on the decision to design a Basin Plan that is flexible and can be adapted to future climate conditions.
A draft Basin Plan that has inbuilt review and adjustment mechanisms is essential in this situation. As a legislative instrument, the Basin Plan will be reviewed at least every 10 years, and can be reviewed as frequently as every 5 years. This means that all aspects of the Plan – such as sustainable diversion limits, the environmental watering plan, salinity plan, trading rules, and risk management strategies – can be reviewed and adjusted at least every 10 years.
It’s very clear that while there are divergent views across the Basin about how water should be managed in the Basin and how climate change should be taken into account, there is also a consistent message that people want to get on with improving our management of water resources.
We believe the quest to find the “perfect science” on climate change is not a reason to delay making a start in reforming our water management and getting more water flowing into the environment.
Our adaptive framework is designed in a way that allows new science to be brought forward and considered.
As an Authority, we need to ask: do we now have enough information to deliver a sound Basin Plan to the Minister to better coordinate and manage water use in the Murray-Darling?
We are very firmly of the belief that we do.
Could we do more work? Yes, we can always do more work. And that’s why we’ve set up an adaptive framework and opportunities to feed new information and ideas in the Basin Plan.
And we’ll continue working with experts in climate science as part of our future work program.
Adaptive Management in a Changing Climate,
Climate change is a hard thing to put a time frame on, who’s to say that the weather paterns we have now are not normal? We just dont have enough data at this stage, come see me in 1000 years not after 100 years of data.
Hi Rhondda
A couple of quick comments in response to your thoughts on climate change and adaptive management. Firstly, the SEACI Phase 1 synthesis report (2010) considered the issue of attribution of the drought to climate change vs climate variability and concluded that there is “evidence that observed changes in the ...
... large-scale circulation affecting south-eastern Australia are associated with global warming which is therefore likely to be contributing to the drought. These changes do not account fully for the ongoing drought, and it remains likely that natural variability is also a contributing factor.”
The report from CSIRO to MDBA in 2009 on “Defining Climate Scenarios for use in the MDBA Basin Plan Modelling” advised “The central question to defining climate scenarios for the Basin Plan is how much of the current prolonged drought in south-eastern Australia can be attributed to global warming, and therefore can be treated as the
start of a persistent change from historical conditions. Several research studies have suggested that at least
part of the current drought is associated with global warming, but it is difficult to separate a global warming
signal from the high natural climate variability. For these reasons, water resources planning should consider a
range of possible scenarios to assess system robustness and resilience to historical droughts as well as future
climate projections.”
This advice on considering a range of plausible scenarios would provide for a robust information base to inform the risk management strategies you refer to. By analysing what outcomes the proposed Basin Plan arrangements would deliver under different plausible climate scenarios we can get helpful information about what desired outcomes are risk due to a changing climate and what undesired outcomes are possible. Having this information may or may not lead to a choice to put different arrangements in place now, but at least provides a stronger information base on which to make these risk-based choices and allows all stakeholder to get a clear position on the risk-choices of MDBA. Certainly periodic reviews provide the opportunity to adjust but in spite anticipated improvements in climate science water resources planning and management will always fundamentally require making wise choices in the face of uncertainty about the future.