Photosynthesis

Open letter to TVNZ

2011-03-17T14:08:00.000-07:00

Dear Closeup people,

I viewed your coverage of Ken Ring's "predictions" on your March 17th 2011 Closeup programme through TVNZ's "on demand" system.

Do you have no shame?

Your reporting was poorly researched, ill-informed, and scared large numbers of people in Christchurch unnecessarily.

You gave very large amounts of airtime to the views of two people who have had extremely limited and not statistically relevant "successful predictions" of earthquakes while ignoring all their failed "predictions".
You placed coverage of these two, Ken Ring and Jim Berkland, alongside two highly qualified scientists (with less airtime for the latter), thereby setting up a hypothetical "balance" between two points of view, when one view was well informed and the other was nonsense. This kind of so called "balance" gives undue credence to the nonsense, and as reporters you should have been well aware of this effect.
You lined up two very talented and famous New Zealanders who clearly have no scientific expertise and used their misguided opinions as support for Ken Ring.
You claimed that two earthquakes (the Napier earthquake of Feb 3rd 1931, and the Feb 22nd 2011 quake in Christchurch) had occurred during combined perigees and full Moons and sensationally implied that this validated Mr Ring's methods.
It appears that you bent over backwards to promote Mr Ring's views and to convince people that they were correct.

Facts that you should have researched before your programme went to air:

1) The Napier event was in fact very near to a coincidence of a full Moon and a lunar perigee
2) The Christchurch event occurred when the Moon was about 50 degrees from full and 3 days past a perigee.
3) If you insist on using isolated events as evidence (which is total nonsense, by the way), then what about the largest earthquake in the recent past in Japan, which occurred when the Moon was closer to apogee than perigee, and almost midway between a full Moon and a new Moon?
4) Of New Zealand's 20 largest earthquakes on record, only 2 were close to a perigee combined with either a full Moon or a new Moon and this is about what we would expect if those earthquakes were randomly distributed in time. If we take a more liberal view of Mr Ring's vague "prediction" method, then we get 5/20, which again is about what we would expect if the earthquakes were randomly distributed in time given the proportions of time represented by this "prediction" window.
5) An analysis of daily seismic intensity in Canterbury since September 4th 2010 shows a 2% correlation with the Earth-Moon distance (an r-squared of only 0.02), and a slightly higher intensity between full Moon and new Moon, although this latter relationship is also exceptionally weak (see http://sciblogs.co.nz/the-atavism/2011/03/01/ken-ring-cant-predict-earthquakes-either/). The correlation with the Earth-Moon distance is totally inadequate for any sort of useful prediction, and the very weak correlation with lunar phase runs counter to Mr Ring's assertions.
6) Mr Ring's "predictions" always have a bob each way, so that having scared the bejesus out of people in Christchurch with his nonsense, if a large earthquake fails to occur then he will point to his website where he says that a quake might not happen. This kind of weaseling is a hallmark of pseudoscience.

So why did you give his "predictions" airtime and attempt to convince people they were correct? What did you hope to achieve? Was it done to try to attract an audience for your advertising clients, with absolutely no regard to the emotional consequences for an already shattered populace in Christchurch? When TV3 tried the same stunt and interviewed Mr Ring, my 9-year old daughter burst into tears in fear of March 20th.

I think your reporting was shameful, and that you only increased the panic in my home city.

So what should you have done? You should have ignored the fringe people with failed predictions. This is obviously the moral thing to have done under the circumstances and it is astounding that your programme went to air.

What should you do now? You should begin tomorrow's programme with an apology, and state that your implied support for Mr Ring's earthquake predictions was totally misguided and poorly researched.

Oh, and just in case you are planning a repeat performance, if we do get a large earthquake this weekend will that single event validate Mr Ring's methods? No, it won't. A large earthquake could still occur this weekend even if they are randomly distributed in time. Does this latter statement also represent a bob each way? No, I am not the one making predictions.

Yours sincerely,
Euan Mason

PS (sarcasm on)

Did you know that over 70% of all earthquakes occurred on days whose English names contained the letters s, y, d and a?

Also, over 70% of all earthquakes occurred on days whose French names contained the letters e, i, and d!

Oh, horrors! March 20th 2011 is a day whose English name contains the letters s,y,d, and a, and whose French name contains the letters e, i and d!

TVNZ should run a Closeup programme on this! (sarcasm off)

The case for science

2011-03-08T17:41:00.000-08:00

A recent correspondent suggested that, "Science has become another holy grail, its importance, capabilities and contribution to society are overestimated, resulting in it being the new 'religion'. The amount of conceptual 'knowledge' might have increased massively, but the pure scientific ethos is getting more and more diluted and polluted, as the arrogance, pride and self-righteousness of present day 'scientists' has increased manifold. This mindset makes it impossible to remain open, objective and self critical, which at least to me, are essential attributes of a real Scientist." and, "All the intellectual 'scientific' knowledge in the world has not added an ounce of inner refinement, humanity or love to society. Just witness present day society: We have jumbo jets, atom bombs and god knows what, but have we stopped killing and hating each other? Instead of using arrows, we use bombs or gas or other scientifically 'evolved' weaponry, but all the selfish and narrow attributes and negative traits have remained the same."

What follows is my response to him:

Science may be amoral, as you say, and clearly technology allows us to express our dark side more destructively. I think that on balance science enhances humanity, however, not just because it allows us to contemplate and communicate this way, but also because in my opinion applied science has led to the rise of middle classes, and we middle classes generally have the time and influence to try to promote more democratic, equitable societies.

Since the enlightenment we have seen a burgeoning of democratic states. This change appears to have arisen in tandem with changes in perceptions of place, cosmology, cause and effect, and personal security that science has helped to bring about. We are not perfect, and our prejudices still wax and wane, but I believe we have made sound progress during the last 500 years. We are more free, more wealthy, healthier and happier on average than our ancestors of medieval times. Our societies are less barbaric in their treatment of illnesses and social problems. All this gives me grounds for hope that we can continue to make a better world, and that science is part of the solution. I accept that I participate in a society that has to continue to change, to become more equitable globally, to offer better opportunities to people, and to live within the capacity of our planet.

I hear your point about scientists being arrogant, a new priestly caste, and maybe sometimes we are too arrogant. All I can say in response is that as a scientist/academic, my integrity is my most valuable asset, and like all other scientists I know, I guard it as well as I can by taking care with my statements and by listening to other points of view with as much charity as I can muster.

The nature of science and studies of complex subjects

2011-03-06T14:19:00.000-08:00

The KenRingGate saga offers us an opportunity to ponder differences between science and other human endeavours, particularly with respect to complex systems. The inverse square law was an early success for those involved in the Royal Society, and the theory can be derived by just thinking about it. The surface area of a sphere is 4pr² (a result first derived by Archimedes), and so observations of a force or energy emanating from a point source should be expected to diminish in proportion to the square of r, the distance of the observer from the source. This is because the same amount of energy per unit time is spread out over an ever larger surface area as r increases, and the surface area increases linearly with r². Predictions made with this theory agree very consistently with actual observations within the usual scales of dimensions we inhabit, and so the theory is a strong one that we confidently use for predictions. But do theories have to be as precise as the inverse square law in order to qualify as "scientific"? As the complexity of the topic of study increases, the precision of predictions tends to decline. Some would argue that this merely reflects our lack of understanding of complex processes such as biology or climate, but it arises also from our inability to precisely define and measure complex starting and finishing conditions. Does this mean that researchers studying complex processes are not practicing science?

The philosopher Karl Popper distinguished a scientific theory from a non-scientific one by saying that the former was falsifiable; that an experiment could be conducted with at least one outcome that would recognisably contradict the theory, which says little about complexity. Many of my colleagues are "Popperian" in their approach to science, although we accept that there is still plenty of healthy discussion about the nature of science. So let's consider the question of complexity in Popperian terms.

Biologists and climate scientists can offer scientific theories or models so long as they could be falsified in ways that take account of probability. We accept that our estimates of starting and finishing states are subject to error, and also that our models of processes may be incomplete, but we can still falsify them if we test them with independent data and use statistical methods. Our theories, models and means of measurement need to be precisely stated, and we also need to include statements of probability. Imprecision and bias can both be regarded as criteria for falsification. If I assert that 95% of estimates obtained from my model of forest growth will be within a given range under certain conditions, and then someone finds significantly more than 5% of estimates outside that range then my model can be said to be falsified. Similarly, if I say that under those conditions errors of estimates should be normally distributed around the model with mean zero and someone finds that they are significantly different from normal or that the mean of the distribution of errors is significantly different from zero then my model can be said to be falsified.

Ken Ring’s “theory” of earthquakes, by contrast, is vaguely stated and predictions from various interpretations of his stated methods do not agree at all well with observations. His predictions sometimes include bounds, but when an event happens outside those bounds he will assert that it was only a bit outside the stated bounds and therefore "validates" his prediction. The vagueness and malleability of his predictions apparently make them unfalsifiable. He does not appear to be behaving as a scientist and his predictions are not terribly useful. The fact that he propagated his predictions and scared the bejesus out of people in an already stressed out city is therefore monstrous, and he deserves strong criticism.

A quick look at Ken Ring's predictions for New Zealand's 20 largest recorded earthquakes

2011-03-01T20:38:00.000-08:00

Mr Ken Ring says that severe, damaging earthquakes are more likely when the moon is full or new and when it is at perigee (closest to the Earth in its elliptical orbit). A quick look at New Zealand's 20 largest recorded earthquakes shows that Ken would have missed most of them. Assume "at perigee" means "closer to perigee than 30% between perigree and apogee at the time of the earthquake", and allow "full" or "new" to mean "within 30 degrees of a full or new moon respectively", then only two earthquakes out of 20 satisfy these conditions: The 2nd equal (with 3 others) highest magnitude earthquake of February 3rd, 1931 in Napier, and the 19th largest of March 2nd, 1987 in Edgecumbe.

Other interpretations of Mr Ring's conditions might be to require a close, recent perigee (say 20% of the way between minimum and maximum perigee, or approximately a 20% likelihood) or alternatively less than 5 days between the earthquake and a perigee (i.e.: roughly 9 days/month). Combine these with "within 60 degrees of a full or new moon" to reflect Ken Ring's broad statements about days from full or new moons (i.e. 2/3rds of the time), and we get 5/20 correct predictions in each case.

On a statistical note, these results are not significantly different from a random occurrence with respect to the conditions imposed, i.e.: there is not a significant correlation between times of occurrence of these earthquakes and my numerical interpretations of Mr Ring's stated prediction method.

Enough said.

Ken Ring is usually a relatively harmless charlatan, but he's not harmless this time

2011-02-28T17:20:00.000-08:00

"20th of March???!!!" wailed my 9 year-old in distress. She had just heard TV3's promotion of an interview with Ken Ring, who normally claims to predict daily weather in advance by copying 18 year-old weather maps. The Moon has an 18 year cycle, and he believes that it's all to do with lunar cycles. He sells books of such mindless weather "predictions", and apart from misleading the public and taking their money, he's usually harmless, but not this time.

This time he has predicted another major quake on March 20th, and added waves of anguish to an already stressed out city. My daughter's reaction was typical, and I have spent plenty of time informing her of just how loopy and inaccurate Ken's weather predictions are. Shame on Ken Ring for adding to distress, for pretending to be a scientist (his earthquake predictions have been found wanting from a statistical point of view), and for making money and notoriety out of other people's misfortune.

Shame on TV3 for giving him oxygen. John Campbell tried to debunk him, but instead of doing a comprehensive job, merely fostered pity for the man by mistreating him at the microphone. He deserves no pity, and definitely no time on TV.

Shake, shake shake

2011-02-27T19:34:00.000-08:00

The February 22nd quake was much shorter than the September 4th one, but perhaps more violent, or the frequency was more damaging. It definitely felt serious at the time. I was under my desk at the University of Canterbury, and after ensuring all the students were out I set off to look for my 9 year old daughter Rhiannon at her primary school and met my partner Carolyn, daughter Kat & Rhiannon on the way. Our home suffered more damage than during the September 4th quake, with many large cracks in the lounge and new cracks appearing in other places. The front door is now difficult to close and we suspect that the foundations have moved. No doubt the Earthquake Commission will sort it out. Some of our crockery was smashed, and several items of furniture were upended along with the fish tank. Drips from the latter on the first floor were attributed to Oscar, our delightful dog, who suffered the same accusation after fishtank water slopped out in September, and he can now justifiably complain that his people tend to repeatedly accuse him of inappropriate toiletry at the slightest provocation.

I find it distressing that we were not welcome to help in the central city where many people were trapped in buildings, and where sadly many died. This quake was "a bullseye", in the words of a structural engineer, being very shallow and close to the city. Engineers expected that many of the city's heritage buildings would fall, and we have lost such gems as the old council chambers, much of both cathedrals, several old stone churches, and plenty of old brick buildings. The Arts Centre is damaged, but it is apparently recoverable. Some relatively modern buildings came down, such as the CTV building on Madras street, which was reduced to a pile of rubble, and the Pyne Gould Guiness building that pancaked. People were, and some still are, inside. Collapse of more modern structures has been a surprise to the engineers, and they are talking about inadequate earthquake standards during the 1960s and early 70s. The Hotel Grand Chancellor will have to be demolished if it doesn't fall down. Two buses were flattened by falling masonry, and many people were injured or killed by falling bits of buildings. The central city was reportedly littered with bodies.

This devastation became evident to us when reports began to filter through to national radio. We had no power, water or sewers, and used a camp stove on the front lawn to cook our evening meal while listening to a transistor radio. Violent aftershocks rattled our house relentlessly, and we felt safer outside. The house has rattled twice so far while I have written this, and each quake is accompanied by a menacing rumble for a few seconds before the sway and creaking begin.

We called my mother in law Pam in Bexley, where liquifaction was worst last time, and resolved to transport Kat to Pam's so that either she wouldn't be alone or she could opt to come to our place. The trip there was harrowing, and my trip back even more so. Fendalton has been hit by liquifaction, and we had to negotiate our way through a very uneven road with plenty of wet sand drifts. This was nothing, though, compared to Aranui. I had planned to go down Travis Rd then on to Anzac Dr, but the latter was closed. Travis road was severely cracked in places, and we had to be alert to avoid plunging the car wheel into a crack or hole which would have permanently immobilised the vehicle. I went past Anzac Dr and turned onto Bower Ave so that I could cross the river on Wainoni St. Bower Ave, Wainoni, Breezes, and Pages Rds were particularly hazardous. It was like a war zone, with large holes in the roads, some of which had already claimed cars and trucks, interspersed with mushy sand drifts that made a very rough passage. The last few hundred metres of Pages Rd were flooded, and we had 6-12" of water sloshing against the sides of the car. That's particularly hazardous because you can't see below the water surface, and by now it was dark and raining steadily. We stopped in the carpark just before the New Brighton Bridge. It was clear that the road into Bexley was impassable, and so after Pam informed us on my cellphone that she wanted to stay at her home, Kat set off on foot while I negotiated my way back through the carnage. By now people had realised that Breezes, Wainoni, and Bower Ave were the way out, and so it was a bumper to bumper crawl.

On the 23rd I called a few friends and family to ensure they were safe. My good friend Phil Barker, a policeman, is working 13 hour days in the city rescuing people. His wife Sonya and their two children have gone to the West Coast. He had no power or water for several days. I distributed swimming pool water to our neighbours for washing. We now have power and water, although supplies of the latter are limited and so we're using pool water whenever possible. Pam's phone was dead on day 2, but Kat found a spot where her cellphone could reach us and we resolved to transport them both to our house where power and water are very congenial luxuries. I was dreading the trip back through Aranui, but it wasn't so bad during the daytime and most of the hazards had been marked. There was still a slow stream of traffic coming out, and we cut an hour or more off our journey by ducking through Marlow and Hampshire streets, which were negotiable and free of other traffic.

On day 4 Pam wanted to clear out some things and so we went back. The flooding was gone, and much of the sand had been pushed into heaps. Pam's house has dropped at least 6 inches, and her driveway, which used to slope away from the house, now slopes sharply into it. Her deck has a 10-15 degree lean. I helped her clean out the fridge and then raised carpet to let it dry. I came across an old couple in a neighbouring house who were living in their garage because rotting carpet made the house smell so foul. It took quite a while and lots of puffing for me to rip the carpet from their lounge and drag it outside.

The University has some damage, but nobody was seriously hurt on campus. We don't know when it will reopen, but I suspect access is at least a week away and probably longer. Carolyn experienced violent sway on the sixth floor of the History Building, and her office was a total mess. She had to get out rapidly and left her computer there, but thankfully it has now been retrieved by University health and safety staff, and she can work.

We've cleaned up around the house, and apart from creaking and groaning (the house, not me) we're sleeping well. We are fortunate to be well, have lost nobody close to us, and to have more amenities than many in this stricken city. I've put the family on a regimen of cleanup, work, play, and then more work, to help us get back to something more normal. Kat said that she welcomed, "Family planning" - well, we've had that too.

To those of you in town I hope you are safe and that life is not too rough for you.

Emissions trading and agriculture

2010-11-17T10:20:00.000-08:00

It is a mistake to consider emissions trading industry by industry, because we are all interconnected. Take, for example, the recent announcement by Hon. Nick Smith, Minister for the Environment, that entry of New Zealand's agricultural sector into the emissions trading scheme (ETS) will be delayed until such time as we see similar progress from other countries on greenhouse gas mitigation. Hon. David Carter, Minister of Agriculture and Forestry, has assured us that the ETS is here to stay, and that investors in new forest should not concern themselves about a premature end to the scheme. It turns out that investment in new forest is overwhelmingly influenced by whether or not agriculture is in the ETS, because so long as farmers' greenhouse gas (GHG) emissions are subsidised by tax payers, agricultural land prices will remain high. The price of land is a critical consideration for forest investors, and so this policy will reduce investment in new forests. It will also mean that farmers who might otherwise consider offsetting their GHG emissions with farm woodlots will be less likely to bother. A high profile politician commented to me that many people in the farming community are in denial about climate change, a denial which is no doubt manifesting itself in the ETS policy announced this week. This policy will influence our capacity to respond to climate change, and it may also ultimately affect foreign buyers of our agricultural products, who will rightly perceive that New Zealand's agricultural produce comes with an extra, pollution price tag.

Open letter to MPs:

2009-08-23T14:21:00.001-07:00

I am writing in support of the repeal of section 59 of the Crimes act.

Our recent referendum on the "smacking" issue contained a misleading question, ironically a kin to, "When did you stop beating your wife?", and the results of the referendum cannot be used to support a reinstatement of the old section 59.

For my parents' generation it was relatively routine for husbands to smack their wives, and we now look at that and wonder how it was tolerated. Future generations will look back on child smacking and wonder how it was tolerated.

Research consistently and conclusively shows that non-violent parenting is generally better for children than parenting that includes smacking.

We are making progress towards becoming a less violent society. The new law sets out an important guideline for parents that will have wonderful outcomes for future generations. Please do not set us back by reinstating the old section 59 of the crimes act.

Comment on forestry and climate change

2009-07-27T18:25:00.000-07:00

This report was released by us through the Science Media Centre of the Royal Society

E. G. Mason and David Evison

Associate Professor and Senior Lecturer, School of Forestry, University of Canterbury. Dr Mason is a member of the NZ Royal Society

The forestry sector makes large direct and indirect contributions to the mitigation of greenhouse gas (GHG) emissions from New Zealand, and its contribution could be even larger if we set the right policy. Forests are a major store of carbon – standing trees, and the organic layer of forest soils are both significant carbon reservoirs.

If the area under forest is increased then the size of this reservoir also increases. New forests sequester extra carbon from the atmosphere as they grow and are therefore carbon sinks. In this way forests can play a significant role in reducing the impact of greenhouse gases on climate change. The rate of carbon sequestration by forests depends on the growth rate of the trees, but planting of new forest, rehabilitation of existing native forest, or allowing scrub or uneconomic farmland to revert to forest are all mechanisms by which sequestration will occur.

Direct contribution

Radiata pine plantations typically sequester between 25 and 30 tonnes of CO₂/ha/year, and forests planted on marginal farmland will store additional carbon that would otherwise be in the atmosphere.

Replacement of grassland by forest is almost insignificant on a global scale (Piers Maclaren, pers. comm..), but is hugely important for New Zealand. The recent release of “New Zealand Energy Greenhouse Gas Emissions” from the Ministry of Economic Development (2009) highlights the important role that forestry plays in reducing our net emissions of CO₂ equivalents. In 2007 our total national greenhouse gas emissions were estimated to be just over 75,000 kt CO₂-e, while net absorption of CO₂ by forests reduced our net national emissions to just under 52,000 kt CO₂-e. Recent projections of sequestration by “Kyoto-compliant” forests (planted since 1989 on grassland) for the first Kyoto commitment period (MfE 2009) imply an average sequestration rate of just under 33 t/ha/year (this high estimate perhaps reflects the current of age of our Kyoto-compliant forests, because sequestration rate is typically lower early in a rotation and most of these forest are middle-aged).

This direct contribution to GHG emission mitigation results from previously planted forest. Historically, planting occurred in three phases, as shown below. In general forests in their first rotation will be the major contributor to reduction in net emissions cited above, although changed management practices on forests planted earlier, that increase the volume of the growing stock, will also contribute. This is discussed in further detail below.

New forest plantings, 1920-2007 (MAF 2008)

When forests are harvested CO₂ may be released into the atmosphere, and so over many rotations the carbon stored follows a “sawtooth” pattern, as shown below.

Tonnes of elemental C stored in a typical radiata pine plantation stand that is periodically harvested. Source: Piers Maclaren[1]

GHG sequestration benefits of afforestation in periodically harvested crops therefore need to calculated by assessing the average carbon store over many rotations.

The cyclic historical pattern of investment in new plantings means that emissions from forest harvesting will also be somewhat cyclic, and those areas planted during the latest period of high investment, in the 1990s, are likely to be harvested during the 2020s. In order to avoid a serious problem in our future national GHG accounts we need to increase the rate of new planting right now. Unfortunately our net stocked area of plantation forest slightly decreased recently, especially just prior to the introduction of a tax on deforestation of “non-Kyoto” forest in 2008, and new plantation establishment is currently at an extremely low level.

New forest planting is a very feasible and viable method to reduce New Zealand’s net emissions. New plantings will provide capacity for New Zealand to implement cost-effective reductions in industry and agricultural emissions, and possibly to develop new sequestration technologies.

Tonnes of elemental C stored in a typical radiata pine plantation showing the average storage. Over long periods of time the average will approach roughly 60% of the final carbon storage at harvest. Source: Piers Maclaren

Indirect contribution

It is not easy to quantify the indirect contribution of forestry, but it likely to be very large. It arises in the following ways:

Land growing forest instead of livestock means our emissions of CH₄ and N₂O, two important GHGs, are much reduced. These agricultural emissions account for roughly half of our total emissions of GHGs, unlike in other first world nations where agricultural emissions are relatively minor components of total emissions.
Wood used as a structural material has much less embodied energy than alternative products, and as our marginal energy production emits GHGs, any reductions in energy use can reduce our overall emissions. Air dried wood has an embodied energy footprint of 0.5 MJ/Kg, compared to 34 MJ/Kg for steel, 90 MJ/Kg for plastics and 170 MJ/Kg for aluminium (Lawson 1996). Concrete manufacture produces CO₂ and also has high energy costs.
Wood is an important, GHG-neutral, source of energy, and use of wood for energy displaces generation technologies that release GHGs. On a global scale this is a very important contribution, with typically 80% of wood harvested in developing nations being used for fuel.
The use of wood in residential construction also acts as a carbon sink, at least for the life of the dwelling. This is not included in the current carbon accounting schemes, which assume all harvested wood as deemed emissions
Other wood uses, such as treated roundwood, non residential construction, also form temporary carbon sinks.

Does the forestry sector contribute to climate change?

If only GHGs are considered then benefits from forestry are overwhelmingly positive, but afforestation can impact on global temperatures in at least one other significant way. The albedo of grassland is typically 0.24 to 0.27 compared to approximately 0.12 for radiata pine plantations (Moore 1976). This means that replacement of grassland by plantation results in greater short wave absorption and this can contribute to increasing temperatures through increases in long wave radiation emitted from the landscape. In an Australian study Moore (1976) observed that long wave radiation above radiata pine forest land exceeded that above grassland by 15% and 25% during winter and summer respectively. On a global scale it has been estimated that up to 40% of the sequestration benefits of replacing grassland with forest might be offset by this effect (Gibbard et al. 2005).

New Zealand’s radiata pine plantations are likely to contribute proportionally more to climate change mitigation because they are very highly productive, and also because they are established in areas where snow is either infrequent or where snow never falls. Snow has a very high albedo, and covering of snow by foliage can greatly impact on energy absorption in the landscape. A brief analysis of this “albedo effect” under New Zealand conditions has been undertaken but the results are not yet available.

The albedo effect is permanent, while CO₂ sequestration benefits accrue primarily during the first rotation after plantation establishment, assuming no changes are made to either numbers of trees/hectare or rotation length. It should be noted, however, that most indirect forestry contributions to GHG emission mitigation are also permanent, and so we shall have to await further quantification of these processes before drawing any conclusions about the significance of the albedo effect in New Zealand.

How could we increase the forestry sector’s contribution to GHG emission mitigation?

With the right policy settings and with appropriate help for landowners, we could markedly increase the GHG benefits of forestry by:

increasing the rate of new forest establishment;
increasing sequestration in existing forests; and
increasing the use of wood as a construction material.

New forest establishment

Many hundreds of thousands of hectares of pastoral land would be more suitable under forest. These include steep and eroding land in the Manuwatu and in the East Coast region of the North Island, where erosion contributes to flood damage and results in demands on taxpayers to provide financial assistance for flood relief and recovery both in the hills and on floodplains below the eroding hill properties.

Re-establishing forest on eroding hill country would not necessary require a significant reduction in farm production; rather it could be achieved by increased use of trees on farms, with generally the land most unsuitable and least productive for farming going into trees. Changes in land tenure would also not be necessary; joint ventures (where the farmer retains ownership of the land, and other investors provided the capital to establish forest) can be established easily under existing legislation.

Eroding hill country in the Manawatu where land would be much more stable under trees and where carbon farming could significantly increase the viability of local communities. Photo: E. G. Mason

The Emissions Trading Scheme (ETS) is available to “post-1989” forest owners, that is, owners of forest that replaced grassland after 1989. They can opt to measure and then sell carbon credits known as Emission Trading Units (ETUs). It has been shown (Evison, 2008) that the ETS will markedly improve the profitability of “post-1989” forests, under reasonable assumptions of carbon price. If administration and compliance costs are not excessive, and the market functions well (i.e. forest owners are able to buy or sell ETUs in the quantity required and at what is seen to be a reasonable price), then the scheme should provide additional incentive for new land to be planted.

Unfortunately, the ETS is currently not providing a significant incentive for forestry, because of the continuing uncertainty around the specifics of the scheme and the prospect that some emitting sectors may not have to participate. The prospect of forest owners having to pay carbon credits for forests destroyed by wind, fire or disease is creating additional uncertainty, with the forestry sector proposing a government-initiated insurance scheme to cover these contingencies. Further uncertainty is created by the fact that the current market is reliant on the agreement relating to the first commitment period (to 2014) and that no agreement to cover subsequent commitment periods is in place yet.

In addition, it is significant that most “post -1989” forest land is on relatively small holdings, and recent afforestation has been mostly on small holdings. This is likely to increase compliance costs per hectare; it is not known if this will discourage new planting by owners of small parcels of land. It is also significant that many people in the farming sector have very little forestry expertise and there is a high level of antipathy towards afforestation of farmland in rural communities. This antipathy is perhaps partly engendered by a perception that industrial scale forestry negatively impacts on those communities.

We might enhance afforestation by:

increasing policy certainty, with both the nature of the New Zealand ETS finalised, and global agreement around future commitment periods; and
providing expertise for owners of small areas of land to assist with afforestation on eroding farmland.

Increasing sequestration from existing forests

With the right incentives, existing forests can be managed over longer rotations and at higher stockings, both of which significantly increase the average amount of carbon stored in forests. Unfortunately, owners of forest planted prior to 1990 cannot accrue carbon credits in their forests, but they have to purchase ETUs if they change land use to cover the “emissions” associated with land use change.

The Ministry for the Environment reports that 566,106 ha of New Zealand’s commercial forest land was planted between 1990 and 2007 (MfE, 2009), and is therefore classified as “post-1989” in the language of the ETS Bill. 1,451,900 ha of commercial forest land are “pre-1990”. This means that 72 % of current planted forest is excluded from earning ETUs in the ETS.

The policy as outlined in the current ETS regulations, in providing compliance with the Kyoto Accord, ignores issues of equity for existing forest owners, by not rewarding owners on a “like-for-like” basis. Essentially, pre-1990 plantation owners have been providing a carbon storage service for free, and the ETS scheme in its current form would impose a penalty should they stop providing this service.

The impacts of this differential treatment for “pre-1990” forest owners are:

Incentive to deforest prior to Jan 2008. It is highly likely that some land owners ‘brought forward” deforestation in order to avoid the penalties that would be incurred from Jan 2008. Thus features of the proposed policy itself generated deforestation.
Increased complexity in decision making for forest owners.
Lack of confidence by the industry, to re-invest in forestry. The proposed inequitable treatment of pre-1990 and post-1989 forest owners has already created this concern, which may be summarised: “If the government can create an arbitrary new rule that makes my forest less profitable than someone else’s, and limits my options by imposing a deforestation tax, then they can do it again in the future.”
The current rules provide a strong disincentive to land use change. The flexibility of relatively unconstrained land use change would not be available to owners of pre-1990 forest land, and this will affect their land values as well as their options for development of their properties. In turn this may influence profits of forest enterprises and overall confidence in forestry as an investment option.
The definition “pre-1990” is applied to the land, not the forest crop, so this constraint is applied for an indeterminate period.

There are two overall consequences of excluding “pre-1990” forests from earning ETUs through the ETS

There is a loss of revenue to those forest growers. This is both inconsistent and a disincentive for those forest owners to manage their forests to meet the nation’s goals.
There will also be a loss of sequestration capability to the nation that could be harnessed by silvicultural changes to these existing forests.

A quick calculation shows the likely magnitude of this loss of carbon sequestration:

Assume sequestering 25 t per ha of CO₂ or 625 T at a 25 year rotation, this implies an average store of 312 T in a radiata pine forest site.

If the rotation age increases from 25 years to 35 years, this would increase the average store of carbon to 437 t.

This is an incremental 125 t per hectare average or 181 million t of carbon potentially at steady state, for the 1.45 million hectares classified as “pre-1990”.

These are rough figures, based on a linear sequestration rate, but they show the scale of the potential benefits of applying the post-1989 forest ETS rules to pre-1990 forests. Note also that, that under Kyoto rules, these increases may not be able to be applied to meet our Kyoto commitments, but they would benefit the environment.

This is a simplistic analysis – it assumes that all forest owners are currently managing their forests on a 25 year rotation, and would change to a 35 year rotation. To minimise disruption to the timber supply, any such change would also need to be managed over a relatively long period.

Potential barriers to full implementation of the ETS for all forest owners are:

Because differentiation of forest land into “pre-1990” and “post-1989” mirrors the Kyoto protocol, any changes to the treatment of “pre-1990” forests may impose extra Kyoto commitments, and it is important to determine who should pay for this. Essentially Kyoto’s treatment of these forests is asymmetrical, because only depletions in storage are recognised.
Any credits provided to pre-1990 forest owners would depend on local demand only, assuming they cannot be applied to our Kyoto commitment.
Impact on market price of units under ETS. Allowing non-Kyoto-compliant credits in the ETS may lower the price of ETUs.
Disruption to the timber industry, if there is a widespread delay in harvests

These areas would need further analysis. Kerr and Sweet (2008) have asserted that full carbon accounting (i.e. including “pre-1990” forests in the ETS) would be possible under Article 3.4 of the Kyoto protocol. If so, barriers 1 and 2 would not apply.

GHG sequestration in existing forests could therefore be greatly enhanced by removing the distinction between pre-1990 and post-1989 forests in the ETS legislation and allowing all forest owners to choose to participate in the scheme under post-1989 rules. More analysis may be required prior to scheme implementation to fully understand transition issues, and the management of risks such as those outlined above.

Increasing wood use as a construction material

Research at the University of Canterbury led by Professor Andy Buchanan is creating opportunities for people to build large buildings predominantly of wood. As noted by Buchanan (2006), GHG sequestration benefits from increasing wood use arise from:

increases in the pool of carbon in wood products
reductions of fossil fuel use in manufacturing wood instead of more energy intensive materials like steel, concrete and aluminium
burning wood waste materials for energy generation instead of fossil fuels
reduced fossil fuel use for heating and/or cooling of buildings

Buchanan’s analysis suggests that item (2) above may be a significant contributor, and that likely impacts in New Zealand would be significant but small relative to our total national emissions. Item (1) is often discussed, but it requires an increase in either total building stocks or in the proportion of wood used when old structures are replaced by new ones. Item (3) may be even more significant than item (2) according to Gustavson et al. (2005).

No major changes in policy are required in order to capture benefits from increasing wood use in building construction, but a coordinated research, education and promotional campaign would be required in order to change people’s habits (Buchanan 2005).

Concluding remarks

The world as a whole is more than meeting its Kyoto Treaty commitments (New Scientist 2008), and so New Zealand has much to gain from carefully setting policy so that the forestry sector realises its potential to allow us fully to meet our own future commitments. This could be done solely through afforestation. For instance, as Piers MacLaren (pers. comm.) points out, if we consistently achieved a new planting rate of 50,000 ha/year, it would take the best part of a century before we established forest on all our eroding landscapes, and meanwhile we would have carbon credits to sell to others on the international market.

If we went further and allowed pre-1990 forest owners to claim credits for increased carbon storage, then we could make a further contribution to the mitigation of climate change, even though Kyoto rules may not allow the sale of credits from such forests in the international market. Moreover, our goal should be to solve the problem, not to just make money from credits.

Finally, developing new building technologies that use wood, and promoting the benefits of timber in construction, will also reduce green-house gas emissions.

Contacts:

euan.mason@canterbury.ac.nz, david.evision@canterbury.ac.nz

Ph: 03 3642584 (Euan), 03 3642987 x 8361 (David)

Mobiles: 027 6082473, 027 5309462

References

Buchanan, A.H. (2006) Can Timber Buildings Help Reduce Global CO₂ Emissions? Portland, OH, USA: 9th World Conference on Timber Engineering (WCTE 2006), 6-10 Aug 2006. In Proceedings of the 9th World Conference on Timber Engineering (WCTE 2006), 4.6.4

Evison, D.C., (2008). The impact of carbon credits on New Zealand Radiata pine forestry profitability. NZ Journal of Forestry, May 2008, Volume 53, No. 1. New Zealand Institute of Forestry

Gibbard, S., Caldeira, K., Bala, G., Phillips, T.J., and Wickett, M., (2005), Climate effects of global land cover change, Geophysical Research Letters 32

Gustavsson L., Pingoud K., and Sathre R. (2005). Carbon Dioxide Balance of Wood Substitution: Comparing Concrete- and Wood-Framed Buildings. Mitigation and Adaptation Strategies for Global Change. Copy obtained at www.joanneum.at/iea-bioenergy-task38/projects/task38casestudies/finswefullreport.pdf in July 2009

Kerr, S. and Sweet, A, (2008). Inclusion of Agriculture and Forestry in a Domestic Emissions Trading Scheme: New Zealand’s experience to date. Motu Working Paper 08-04. Motu Economic and Public Policy Research, Wellington

Lawson, B, (1996), Building materials, energy and the environment: Towards ecologically sustainable development, RAIA, Canberra

Levack, H. H., (1991). Changes in Forestry Taxation. NZ Journal of Forestry, August 1991, Volume 36, No. 2. New Zealand Institute of Forestry

Ministry of Agriculture and Forestry, (2008). National Exotic Forest Description, 2007. Ministry of Agriculture and Forestry, Wellington

Ministry for the Environment, (2009), Stakeholder progress report, Looking at LUCAS: Land Use Carbon Analysis System, Ministry for the Environment, Wellington

Ministry of Economic Development, (2009), New Zealand Energy greenhouse Gas Emissions, Ministry of Economic Development, Wellington

Moore, C.J., (1976), A comparative study of radiation balance above forest and grassland, Quarterly Journal of the Royal Meteorological Society 102 (434)

New Scientist, (2008), World ahead of Kyoto emissions targets, New Scientist 2683

[1] Reprinted with permission

Stupidity rules the climate change roost

2008-11-26T14:45:00.000-08:00

So, we are to have a "review" of the anthropogenic climate change question with selected "international experts" sponsored by the ACT party, and our Emissions Trading Scheme will be delayed in the meantime. A formal agreement between ACT and National says that a select committee on climate change will:

“...hear competing views on the scientific aspects of climate change from internationally respected sources and assess the quality and impartiality of official advice.”

Rodney Hide, leader of the ACT party, has said,

"Al Gore is a phoney and a fraud on this issue and the emissions trading scheme is a worldwide scam and a swindle."[1]

Mr Hide’s mind is clearly made up, and his agreement with National implies that public servants are providing biased advice. When he says that the emissions trading scheme is a scam and swindle, is he accusing officials of promoting a scam? Whom will Mr Hide select as “internationally respected sources” when he wants a particular outcome?

"Laughable" doesn't really do this justice. Rodney Hide is pursuing a small slice of the popular vote in a way that is not only damaging our credibility, but will cost us dearly financially and hurt the environment - three blows against the nation from just one incredibly stupid, ill-informed ACT policy.

A recent report in New Scientist pointed out that the world is more than meeting its Kyoto commitments, so the line that, "nobody is meeting their commitments and so it will all be scrapped" is just ignorant bullshit. If we fail to meet our Kyoto commitments we will have to pay - billions of dollars most likely.

The "review" has undermined potential investments in new forests that reportedly run into 100s of millions of dollars, i.e.: 10s of thousands of new hectares of forest that could be soaking up CO₂. If we don't plant more forests now, then during the 2020s when the 1990s plantings are harvested we will pay for a huge hole in our national carbon accounts.

The idea that ACT, in cahoots with the "Climate Change Coalition" - Owen McShane et al. - have the inside story on climate change in the face of years of careful research by responsible scientists is manifestly stupid, and that a responsible government would allow such a small dog tail to influence policy in such an expensive, damaging way, implies a whole extra layer of stupidity.

[1] NZPA | Tuesday September 2 2008, reported in the National Business Review

It’s often the people issues that make forestry difficult

2008-06-17T22:01:00.000-07:00

At the NZ Institute of Forestry’s annual conference last month we traveled into the Manawatu to see for ourselves erosion that plagues hill country farmers and doubly plagues dairy farmers in the Wairarapa every time there is a flood. After the last flood taxpayers provided more than $200 million to help clean up the mess. About 175,000 ha of the Manawatu needs afforestation, according to the New Zealand Empirical Erosion Model that John Dymond showed us. We also heard Frank Brenmuhl, Chair of the Dairy Farmers of NZ, proclaim that “somebody had told him” he needed 17% of his farm converted to trees each year in order to produce greenhouse gas (GHG) neutral milk. His plea was that farmers had no viable alternative but to continue emitting GHGs, and that they would “never” go along with the New Zealand Emissions Trading Scheme (ETS).

The amount of forest required by dairy farmers to comply with the ETS is open to some dispute, but “17% of their land each year” seems to be inflated by a factor of around 30 if total greenhouse gas neutrality is the goal. In addition, the ETS, as currently constituted, would not require Mr Brenmuhl to be fully GHG neutral until 2025, and so to initially comply with the scheme a very small investment in forestry would be required. In fact, he could use a small portion his dairy receipts to finance a joint venture with a hill country farmer to afforest eroding land, thereby allowing both of them to meet ETS commitments while reducing the likelihood that dairy farmers on the flats will need another bailout from taxpayers. Technically this seems clear enough.

The problem is, how do we enable the joint ventures to happen? To illustrate why this is such a difficult issue, consider another part of our field trip in the Manawatu. We passed several blocks of radiata pine plantation, and our guides almost invariably said that the forests had been planted because either someone had died or someone’s marriage had broken up, necessitating the liquidation of their farms. Forestry companies apparently accompany calamities like the grim reaper in these farming communities. The same communities have critically small schools, rugby clubs, and social networks that they feel are threatened by an ever growing blanket of radiata pine. One of the Horizons Regional Council employees was “ordered out of a valley” by local residents when he was trying to help them plan afforestation on eroding hill country. Some of the hill farms reputedly make negative rates of return on capital, but it is the lifestyle that matters.

Helen Moodie of the Landcare Trust presented a moving account of her interactions with farmers, including plenty of hints about how to work with the farming community in positive ways. We often get it wrong, it seems. In recent email correspondence, Mike Halliday, a former President of the NZ Farm Forestry Association said, “…you need to be careful with the tone of any response, in my experience (about 40 odd years of SLM) - and one of the reasons I didn't attend your recent conference - the Institute tends to display a rather patronising, 'we know what’s best for you' view on land management, that doesn't go down well with the poor struggling peasants who can't afford to put a new roof on the shed.”[1]

Yes, it is the people issues that make forestry difficult, and in saying that I’m pointing the finger at us – foresters. Congratulations to the organisers of the conference for bringing together such a diverse cross-section of the land management sector. The lesson for foresters is that it’s all very well to believe we know how things might work out technically, but we have to make a greater effort to understand where other people are coming from and consider their views when we try to help. Maybe Landcare Trust could do the enabling and forestry consultants could provide technical advice later, if and when the need for it is accepted by landowners.

[1] Reprinted with Mike Halliday’s permission

"Smacking" is not "good parental correction"

2008-02-29T13:27:00.000-08:00

So, if it crosses the 10% of registered voters barrier, we in New Zealand will be asked in a citizens initiated referendum:

"Should a smack as part of good parental correction be a criminal offence in New Zealand?"

The referendum question implies that smacking can be part of "good parental correction", and we wouldn't want to outlaw "good parental correction", now would we? How ironic that this is in the same category as the proverbial leading question, "When did you stop beating your wife?".

How ironic also that the second question asks, "Should the Government give urgent priority to understanding and addressing the wider causes of family breakdown, family violence and child abuse in New Zealand?" when the repeal of section 59 of the Crimes Act resulted from exactly that urgent priority and sought to remove a legal loophole that allowed child bashers to get away with it.

The word "smack" is a euphemism for violence against children. If I "smacked" my neighbour I would be rightly subject to prosecution for assault. If a child "smacked" another child, that child would be called a bully. It is inconsistent for parents who agree with laws against assault and who oppose bullying to think that they have a right to bully and assault their own children.

Climate change: Don’t just leave it up to scientists (hang on, I’m a scientist!)

2008-02-25T21:12:00.000-08:00

Decisions about our responses to climate change need to be distinguished from scientific hypothesis testing.

Some people point out that there are uncertainties in global climate science and argue that we should not act until the matter is clarified. Science thrives on debate, and we should welcome questions about what we think we know. The debate has shifted in the past few years, with fewer people suggesting that global climate is not changing, and more discussion about whether the observed change is affected by our activities or only by other factors.

Scientific statements are almost always associated with uncertainty, but does this make them so unreliable that we shouldn’t act in response to them? It is reasonable that our responses should depend on both the degree of uncertainty and costs associated with alternatives.

When action requires a lead time, there comes a point when you have to act or risk wearing negative, irreversible consequences. You have to make an interim assessment of the arguments of those who claim that something is happening versus those who are trying to refute it. In accepting a claim for the purposes of acting, you are not saying with absolute certainty that the claim is true, you are simply recognizing that waiting for certainty and consensus is an unattainable luxury. Given how argumentative we scientists are, certainty will be available after the predicted events have, or would have, actually occurred, and even then we’d be arguing.

Imagine that thousands of the best astronomers in the world had worked intensively on the issue of whether a particular asteroid was going to hit the earth and had argued their findings line by line with government representatives who wanted to avoid the cost of trying to do anything about it. Suppose also that with current technology for diverting asteroids we had to decide now whether to act on this advice or not. Even if there was a small number of astronomers claiming that the asteroid was not going to hit, we could simply not afford to hold off action until the debate was finally resolved to the satisfaction of all astronomers. The best way to think about this issue is to imagine explaining our decision to someone after the asteroid impact. How much sense would it make to say at that point in time: ‘well, a group of the best astronomers in the world deliberated on this issue and decided that the asteroid was going to hit, but we decided to go with a handful of skeptic astronomers who were arguing against it and delayed acting until the issue was resolved.’?

It is similar with climate change. All scientists agree that there are uncertainties associated with climate change, but they differ as to its degree. Generally those considered to be “skeptics” think there is more uncertainty than do the majority of climate scientists, including those who wrote reports for the Intergovernmental Panel on Climate Change (IPCC). The IPCC writers believe that we understand enough about global climate to be able to state that humans are contributing significantly to climate change by emitting greenhouse gasses, to the extent that they can assess the likelihood of different levels of temperature increase. They also believe that we need to act quickly if we wish to avoid it. Never the less, like all good scientists, they qualify their conclusions with statements about the likelihood of being wrong.

Climate change and meteorite impacts differ in that the former involves a lower level of understanding about the processes, but if climate models accurately reflect key processes then current conditions affecting the likelihood of climate change can be stated with greater confidence than those affecting meteorite impacts.

Climate change, whether anthropogenic or not, may cost us dearly. The Stern report suggested that climate change might result in a 20% reduction in global per capita consumption. Assuming that recent climate change was mostly due to greenhouse gas emissions, Stern further claimed that the cost of a satisfactory response might be a 1 % reduction in per capita consumption. According to the BBC news:

Tony Blair said the Stern Review showed that scientific evidence of global warming was "overwhelming" and its consequences "disastrous". (BBC news, 31 October 2006)

The Stern report said nothing new about the science of global warming, so what did Mr Blair mean? While Stern offered no new science to decision makers, he greatly clarified the stakes for humanity if the science is right. No doubt that was why Mr Blair welcomed his report. We need to distinguish between the science and the decision whether or not to react to the likelihood of anthropogenic climate change.

Paul Duignan[1] makes this point well. Scientists place a very demanding standard of likelihood on their assertions, so that chances of being wrong have to be at most 5% before results are labeled “significant”. Duignan argues that using this high standard of likelihood is fine for basic science, but it is inappropriate for decisions about whether or not to act to mitigate climate change, given the stakes clarified in the Stern report. He says that scientists may not be sounding the alarm loudly enough. Another way to think about this is to contrast scientific decision making with that of engineers. Unlike scientists, engineers use a very low standard of likelihood when designing a structure, often over-engineering by a factor of five to ensure that the structure doesn’t fail. They understand the difference between increasing certainty about being right versus increasing certainty about being safe. In a sense, if the majority of climate scientists are right, we are designing our future climate, and if we choose to do nothing then it is unlikely to be a safe construction. Given the stakes identified in the Stern report, the cost of mitigating climate change is lower than the likely cost of assuming that the majority of climate scientists are wrong and a relatively small minority comprising contrarians are right.

[1] Duignan, Paul, Unorthodox use of raw conservative climate change estimates, Article in Preparation 2008

Carbon storage and the New Zealand Emissions Trading Scheme: Rewards for new producers of an old product

2007-12-18T13:13:00.000-08:00

The announcement of the New Zealand Emissions Trading Scheme (ETS) reflects new, enlightened attitudes towards cleaning up our own messes, and while foresters have much to contribute, we are heading for some speed bumps.

Atmospheric carbon absorbed by trees will become a tradable commodity, which is a double-edged sword for forest owners. Owners of post-1989 forests planted on grassland will be able to sell estimates of New Zealand Emission Units (NZUs are each equivalent to one tonne of CO₂) absorbed by those forests. However, lawmakers have implicitly assumed that the ETS should encourage people to change their behaviours, rather than reward desirable, current behaviours. Therefore owners of pre-1990 forests will receive no credits for the carbon their forests have absorbed, but they will be liable for carbon emitted if they choose to deforest. There will be a small allocation of 39 free deforestation NZUs per hectare to all pre-1990 forest owners. To put this into perspective, consider that a typical radiata pine plantation absorbs around 30 NZUs per hectare per year. Those who wish to deforest beyond the limits of their allocations will either have to generate NZUs by planting new forests on grassland elsewhere, or purchase extra ones on the open market.

NZUs should increase in value as the scheme unfolds. Sectors will be brought into the scheme one by one, with forestry first off the blocks in 2008, followed by the transport sector in 2009, other energy and industry in 2010, and finally agriculture (methane from livestock contributes almost 50% of our total greenhouse gas emissions) and waste management in 2013. Units sold in 2008 may therefore be considerably less valuable than those sold in 2013. Non-forestry sectors tend to be greenhouse gas (GHG) emitters, and they will initially have free NZU allocations, topped up annually, equivalent to 90% of their 2005 emissions. From 2013, they will experience a reduction in free NZU allocation of 7.5% of their 2005 emissions each year between 2014 and 2025, and have no free NZUs thereafter. This should further increase the value of NZUs.

Pre-1990 forest owners stand to lose land value because changing to some other land use may become prohibitively expensive. If they deforest they will have to purchase increasingly scarce NZUs, with the amount most likely estimated from a table of values that is yet to be released. In addition, they would not be entitled to free allocations of NZUs for any subsequent land uses that emit GHGs (see further comment on this rule below).

Post-1989 forest owners can choose to register for the ETS, and accrue NZUs as their forests grow. They would have to surrender NZUs at time of harvest, however. If they chose to replant then the amount surrendered would probably be about 80% of the amount accrued, because roots and debris left after harvest take a few years to break down. Someone with many age classes in their estate might find that NZU liabilities generated by harvesting of some stands were balanced by NZUs absorbed by other stands. As the price of NZUs is projected to rise with scarcity, commentators are suggesting that it may be wise for post-1989 forest owners to retain most of their NZUs. Retaining permanent forests with little or no harvesting may become an increasingly attractive, albeit risky alternative which would allow owners to capitalize their NZUs.

While designers of the ETS would ostensibly like to encourage afforestation on pastureland, two perverse rules of the scheme appear to discourage prospective farm foresters, at least until reductions in free NZU allocations become extremely painful for farmers. If GHG emitters cease trading then they lose their free allocations, and new emitters have no rights to free units. So your neighbouring dairy farmer is going to figure that she’ll only lose free NZUs by establishing a forest, and changing back to dairy farming would be financially unworkable in at least the near future. We need new afforestation now; otherwise our unbalanced national estate will produce a carbon deficit in the landscape if trees planted during the 1990s are harvested on schedule.

One little-noted hazard for forest owners is that changing land from grass to pine darkens the landscape, increasing the amount of energy absorbed. An email exchange between me and Dr Ken Caldeira, of Stanford University, yielded a “back of the envelope” calculation suggesting that a portion of the benefits of CO₂ absorption by radiata pine might be negated because of this effect. This may mean that planting tree species with lighter leaves, such as Eucalypts, may provide greater climate change benefits. As responsible environmental stewards we should investigate the matter fully, and I am encouraging Dr Caldeira to publish his calculations in a peer reviewed journal. So far this “albedo” effect is ignored by the Kyoto treaty and by the ETS, but there is no guarantee that policy makers will continue to overlook it.

Similarly, some notable solutions to climate change provided by forestry are recognized neither in the Kyoto agreement nor in the ETS. According to Lawson[1], air dried wood has an embodied energy footprint of 0.5 MJ/Kg, compared to 34 MJ/Kg for steel, 90 MJ/Kg for plastics, and 170 MJ/Kg for aluminium. As much of our marginal energy comes from fossil fuels, building with wood instead of these other materials can help us to reduce emissions. Furthermore, wood in use represents another reservoir for carbon, and forests offer carbon-neutral solutions for creating transport fuels or direct energy generation from wood combustion. We need to be just as forthright about these benefits as we are in acknowledging adverse features like the albedo effect.

Readers might be forgiven for assuming that I dislike the ETS, but they would be mistaken. We need to change our behaviours, and the ETS is a worthy attempt to encourage us to do so. In principle I support it, and the difficulties of making this kind of policy have been courageously confronted by government officials. I am concerned, however, that incentives for forestry may be inadequate, and it is ironic that a scheme designed to encourage change may initially reduce land-use flexibility, with farmers looking askance at afforestation that would lower land values while lobbying hard to have agriculture removed from the ETS altogether.

[1] Lawson, B 1996 Building materials, energy and the environment: Towards ecologically sustainable development RAIA, Canberra