HIGH FLYERS THINK TANK

Innovative technical solutions for water management in Australia

University of Adelaide, 30 October 2006

General discussion 1
Chair: Professor Kurt Lambeck

Sue Serjeantson – I wonder if we could have clarification from the plant experts, please: there is an urban myth at the moment that massive clearing in Western Australia has forced moisture-bearing weather south of the continent. I am seeking expert opinion as to how much merit is in that argument, and what might be done to address it if indeed it is the case.

Nick Schofield – This is not really an expert opinion, but I am aware of some of the research that has been done on it in the Western Australian context and elsewhere. There does seem to be a definable, quantifiable effect, that changing vegetation in the landscape will affect both the local climate and a bit further afield. At Land and Water we are supporting a project that is exploring that issue across Australia, and there is a lot of work that has been done on that in the Amazon, in particular, where it shows a stronger effect. So there is an interaction, but it is certainly not the cause of the massive shifts in rainfall patterns in WA in total. It is a component, as I understand it, but not the full story.

Barry Brook – There is also a lot of discussion in the palaeo literature about the potential effects of vegetation clearance in Central Australia and how that may have affected the penetration of the tropical monsoon. The idea is that as vegetation was cleared by Aboriginal burning, that caused a loss of evapo-transpiration in those areas and weakened the penetration of the monsoon, such that it caused the drying in arid Australia. So there is argument that there is prehistoric precedent for this effect, on a very large scale.

Participant – Does the clearing correlate with the changes that have been observed more recently? The clearing goes back a long time in Western Australia. I would like to ask the people who responded to that question: does that correlate with the changes in weather patterns more recently?

Nick Schofield – I think the phenomenon that is occurring in WA is largely driven by other effects. As you are probably aware, there have been two step function changes, one in the 1970s, the first reduction in rainfall of around about 20 per cent or something like a 40 to 50 per cent drop in stream flow into the Perth dams. Interestingly, there has been a second step function in the last five or six years' data, from 2000 to 2006. There are now reduced stream flows down to 80 per cent of pre-1970 levels, so it is an absolutely phenomenal step function change.

As you say, I don't think the vegetation is the single driver of that. There are other broader-scale climatic effects happening – not fully understood, but climate change is a component of that, I understand.

Participant – Just another comment: the water supply in Western Australia and Perth is primarily based along the coastal fringe. The prevailing weather patterns that carry moisture come in from the sea, so inland clearing of vegetation is unlikely to have a direct impact on the Perth storages in that way.

What seems to be a much bigger thing – this is what a lot of the climate research into Perth's problems has been looking at – is that the weather patterns and the weather systems that bring those frontal systems across appear to have moved further south, and in the northern hemisphere have moved further north. That is thought to be of much larger impact, at this point, than any local effect. The fact is that the rain in Perth comes in from the coast, so clearance inland is really highly unlikely to be the major driver. You are talking about a global weather pattern there.

Kurt Lambeck – It is part of a global change, or a very large-scale change, rather than a local one, I suspect.

Duncan Cook – I just wanted to agree with those points. I think the present climatic changes we are experiencing are driven by a process much larger than localised vegetation clearance. Even though that connection is important, it is nothing compared with ENSO-scale variations.

I also wanted to go back to the point that was made briefly before about the possibility of prehistoric human activity and vegetation clearing. That is just a theory and is not a scientific fact by any stretch of the imagination at the moment.

Participant – I am not really sure that this goes into the plant or soil area, or whether it is a more general question. But if we are supposed to be considering the broader issues of water management in Australia, are we looking at other ways that we could be using our land and our water resources? We are a net exporter of virtual water in Australia, when we are a continent that is one of the driest in the world. As policy do we really want to be doing that, or would it be better to use our water for other purposes such as manufacturing, having solar farms where we used to have agriculture, or making more energy so that we can, say, manufacture? It is a really big question: are we using our land and water resources as we want to do?

Kurt Lambeck – I think that is an important question that needs to go down on our list of points. At lunchtime somebody said to me that 80 per cent of Australia's agriculture products come from 20 per cent of the land. I don't know whether that means that the other 80 per cent of the land is using a lot of water that is, effectively, very inefficiently used. There may be merit in exploring that point a bit further: if 80 per cent of our so-called agricultural activity is not obviously terribly effective, how much of the water is that using and would that water be better used in different ways?

Nick Schofield – Those figures may have come from the National Land and Water Resources Audit. Another important figure is that 80% of the profit of agriculture comes from 1% of the land area in locations such as the Murray Darling Basin.

Ross Wilkinson – I thought the comment Sue Serjeantson made was very interesting, because I am not sure that as a country we know how to have that discussion. How do we actually work out what is going on – what are the risks, what are the benefits, et cetera? I guess, going back to Blair Nancarrow's comment about how do you get community engagement in these sorts of things, we don't know how to have that discussion at a scientific level quite yet, and we certainly don't know how to involve the community in that discussion. So I think that we need to somehow or other have a kind of quantitative approach that allows some of those discussions to take place, and then a corresponding qualitative approach that enables the other part to be put into play. If we are going to try and affect water usage in the country, we need not simply to come up with better science but to come up with better science communication, which involves listening, not just telling.

Participant – I guess this is something which I refer to as cultural baggage. Australia has a sort of mentality of itself as being largely rurally driven – built on the sheep's back. I wonder if we are going through a bit of a change now, because we are seeing the major economy being driven by mining – mining bringing a lot of money into the country – and yet a lot of expense being given to prop up a lot of perhaps marginal rural activities. Certainly at the moment we are driving off that Eurocentric baggage and culture, and maybe that is slowly changing. The country might start slowly changing, but the ceiling to speed it up would be to try and get a little bit more political will, as it were, to achieve that change.

David Wigginton – Just in relation to the question of Australia being a net water exporter: I have seen a couple of presentations lately from Paul Perkins, from ANU, where he has presented some figures which suggest that although Australia is the driest inhabited continent, we actually have the largest water resource per capita of any country. Also, a number of our rural industries are the most efficient in the world, in terms of their production systems. He has actually presented the challenge that Australia has the potential, or maybe even the responsibility, to become a major agricultural producer to feed the world's population, especially in countries that are unable to do so themselves. I am not necessarily supporting that view, simply putting it up there.

Nalin Sharda – I have a question for any expert here who knows about the scheme that has been talked about in the past of a channel to bring seawater inland. That would change the ecology and bring more rain in, et cetera. I am not an expert – I am an ICT person – so I would like to hear from somebody who knows more about that proposal.

Kurt Lambeck – There may be an experiment going on in nature that could actually enable us to address this in the not too distant future. I have a suspicion that during the last Interglacial, when sea levels were a little bit higher, there was marine water coming all the way into some of the lakes in South Australia that are very close to or below present-day sea level, so we may actually see this in a little while! But somebody else may want to give a more sensible answer to this.

I think the challenge I would see would be how to prevent that from becoming a big stagnant pool of water. To get the circulation in and out would be the challenge, I think.

David Chittleborough – Just a comment on the speaker before last, who mentioned the ANU research which showed that we had perhaps the largest amount of potable water per head of population: I have heard that figure as well, but I think it must surely rely on the fact that we have such vast resources of water up in the north, which of course is a real challenge for agriculture and living generally.

And to just touch on what Katherine asked a few minutes ago, about looking at various plant uses of water: maize is about half a megalitre per ton, it takes about one megalitre of water to produce a ton of wheat. And of course rice and cotton are two or three times that. But if we are looking at that, then we need to look at the whole industry, and have a look at our animal livestock industry, where the figures of water per ton are vastly different from that. If we are going to go down that route, then we will have to look at the livestock industry as well.

Kurt Lambeck – Can you tell us what the figures are?

David Chittleborough – Well, the figures are available. I am not sure what the livestock use is, but it is an order of magnitude, at least, greater than the amount of water used per ton for grain, for example. But then there are all the other side effects that go with livestock industries as well, in terms of water quality – a lot of the phosphorus and carbon and other problems.

David Wigginton – I would just like to make a note of the comparison between those products in terms of their water use. I am not sure how you would compare a kilo of meat with a kilo of wheat with a kilo of maize, especially going then to other products that aren't actually measured in kilos anyway. If you were to look at them on a value per megalitre basis, I imagine you would get a completely different set of numbers from those you would get if you looked at it on volume or mass or whatever.

Jim Donaldson – My question is about identifying knowledge gap. Certainly June Marks, in her wrap-up, and I think one of the other presenters, talked about data driven solutions or outcome solutions, and June mentioned this whole institutional issue. I couldn't help thinking, when listening to Alex Zelinsky about the Water Resources Observation Network and real-time data sources, monitoring et cetera: who is it that is going to be using this data in either a policy or an operational sense, and how do we connect science and research to those users and the types of decisions and outcomes that are being sought? It seems to me that's a major institutional challenge and an organisational challenge – in terms of not just how to organise data but the relationships and arrangements, and the understanding of the framework of what it is that we are trying to do. I can't help thinking that there is a big research agenda there, just in getting some of those things clear.

Zo? Sofoulis – I am no expert about this, but just to make a general comment: from some of the things that I have heard today, there has been a tendency to separate the sciences and those experts from the humanities and social sciences, and to rely on scientists getting data and coming up with solutions and then trying to persuade the users to accept them in some pseudo-democratic process of choice, after all the choices have been made.

I am just wondering if a lot of the discussion today is pointing to the need, in relation to these issues of major community import, for ordinary people to be really included, right from the start, and the need for researchers in natural resources management – this is already happening, I believe – to work much more closely (not just using some token notion of the 'community' or some sense of 'average opinion' gained by telephone polling) with social scientists, humanities people, human factors people, as well as change agents and keen people in the communities of stakeholders that they are interested in, to really develop a much more integrated approach to problem solving in these areas, and not to leave the users out to the end.

The other thing would be to say that I am just amazed that, when many scientists and natural resource managers and engineers are talking as experts, it seems as if they absolutely forget all of the things they know when they are standing in their shorts in the backyard, doing a spot of gardening, or when they're talking to their relatives over a meal. They forget a lot of commonsense things about humans and cultures and so on. So perhaps working in more interdisciplinary frameworks would be a way of helping people maintain their expert sense and forward that, without losing touch with commonsense and what ordinary people can cope with and want.

Michelle Bald – This follows on from that, in a way. Being involved in a government program which is 'imposing' something upon people and doing all the things that Blair said we shouldn't do, and knowing that we are doing it the wrong way, I guess my concern – and this is what I have been struggling with today – is that our time to act is now, particularly in terms of protecting the environment and a lot of what we are trying to do in reinstating environmental flows and those sorts of things. This is a question for the social scientists, I suppose. We have to get the community on board in the engagement that you are talking about, but I am a little concerned that there is a mismatch of time. We need to act now, but I am seeing this process of engagement as a long one. I am just wondering if someone can respond to that.

Blair Nancarrow – I have seen the same problems now around water resources management for the last 20 years, and scientists saying exactly the same thing for the last 20 years, that now is the time to act and engagement is going to take too long and it is going to cost too much money. And guess what? We are still arguing about the same things that we could have started working on 20 years ago, and we could have had a solution by now. I think we have got to stop using this excuse that it has to happen now. Yes, it does have to happen now, but we have to start doing it the right way now, because you don't save any time, you don't save any money by trying to take shortcuts. We have just got to bite the bullet and look at the fact that it is going to take time with people.

Kurt Lambeck – Perhaps this may be the time to break. In your breakout sessions you might consider how best to spend $100 million, if given the chance, on innovative technical solutions for water management in Australia.