Claims that tropical forests are declining cannot be backed up by hard evidence, according to new research from the University of Leeds.
This major challenge to conventional thinking is the surprising finding of a study published today in the Proceedings of the US National Academy of Sciences by Dr Alan Grainger, Senior Lecturer in Geography and one of the world’s leading experts on tropical deforestation.
In the first attempt for many years to chart the long-term trend in tropical forest area, he spent more than three years going through all available United Nations data with a fine toothcomb – and found some serious problems.
Read the entire EurekAlert write up here.
Philip Stott also has a good write up here.
The abstract from the paper is below:
Difficulties in tracking the long-term global trend in tropical forest area
Alan Grainger*
School of Geography, University of Leeds, Leeds LS2 9JT, United Kingdom
Edited by B. L. Turner II, Clark University, Worcester, MA, and approved December 3, 2007 (received for review April 3, 2007)
The long-term trend in tropical forest area receives less scrutiny than the tropical deforestation rate. We show that constructing a reliable trend is difficult and evidence for decline is unclear, within the limits of errors involved in making global estimates. A time series for all tropical forest area, using data from Forest Resources Assessments (FRAs) of the United Nations Food and Agriculture Organization, is dominated by three successively corrected declining trends. Inconsistencies between these trends raise questions about their reliability, especially because differences seem to result as much from errors as from changes in statistical design and use of new data. A second time series for tropical moist forest area shows no apparent decline. The latter may be masked by the errors involved, but a “forest return” effect may also be operating, in which forest regeneration in some areas offsets deforestation (but not biodiversity loss) elsewhere. A better monitoring program is needed to give a more reliable trend. Scientists who use FRA data should check how the accuracy of their findings depends on errors in the data.
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
The abstract is at pains to describe the difficulties in tracking the long-term global trend in tropical forest area – “a better monitoring program is needed to give a more reliable trend.”
How does this become “No Convincing Evidence for Decline in Tropical Forests”? Maybe it’s all those cherry trees…
Easily – because there is no hard evidence for tropical forest decline – the data is poor. ‘Cherry trees’ are required for claiming a decline in tropical forests!
To describe stotts’s as a good write-up is a bit of a stretch. ONE person says there is some doubt about the data, and Stott then states that it’s all a myth. For you to be consistent, and Stott for that matter, you would apply the same sceptisism to yourself. I.e. no proof that tropical forests are increasing, no proof that tropical forests are not declining. Where is your proof that biodiversity is increasing? Where is your proof that what is replacing tropical deforestation is biologically equivalent to what is being destroyed.
Yawn, since Paul was making none of the claims you made above, I’ll yawn myself.
Everything is changing as the world develops. There are women in India who would rather the mining companies went home & left them to their life, in their tropical rain forest.
http://au.youtube.com/watch?v=tEkzssr4pDM
“the data is poor.” Well exactly. The fact that the available data may be derived from different methodologies and insufficient or limited in scope means that no conclusion should be drawn from this study – certainly NOT that there is no hard evidence for decline in tropical forests. The author also focuses on tropical forest area not the tropical deforestation rate. What are the trends in tropical deforestation rate? How reliable is the data.
You cannot scientifically conclude what you have attempted in this post based on what you have presented. You can certainly spin it that way as a matter of preferred belief.
It is highly unlikely that rainforests are increasing globally – for a start it can take many centuries to generate climactic forests of any kind. The increasing rate of the clear felling of rainforest in the Amazon and much of Indonesia suggests that even if regeneration is occurring it is not replacing like with like. Even the author concedes biodiversity loss. Hence the focus on total rainforest area rather than on deforestation rates. They are not the same thing. A rainforest area which has had 30% of its forest removed within its borders can still be considered a rainforest area of the same size as before. There just happens to less actual rainforest in the rainforest area.
To suggest otherwise is disingenuous. But hey, this is JM’s blog site.
It would be disingenuous to claim certainty from uncertain data, which has not been done by the author, or this post. As for the UN……
“It would be disingenuous to claim certainty from uncertain data”. Exactly. Glad we cleared that up.
So rather than address any substantive points you bring up the UN?? WTF??
Slim – The UN IPCC claim certainty out of uncertainty. I suggest you spend time correcting false information on your own blog:
“Long time contributor Luke, Jennifer’s token greenie who owns an ecotourism property in the Daintree, appears to have departed with a scathing assessment of Marohasey’s blog site.”
I suggest you remove this false statement. Our co-blogger Neil owns an ecotourism property in the Daintree and is still very much with us. ‘Luke’ is the pseudonym of a rather too prolific non-informative comment poster who has exiled himself from the blog following warnings about his language and conduct.
“a rather too prolific non-informative comment poster” – Paul Biggs
I’ve learnt from many different people on this weblog. I haven’t always agreed with them, but I’ve been able to produce informed opinions from some of the posts and links. I most certainly would not say Luke has been uninformed, and suggest that that is perhaps your opinion, not necessarily that of all contributors here.
Many of Luke’s posts were informed, but he also had a habit of making many repetitive ‘blog-fight’ comments with inappropriate language. The main point of my post is that ‘Luke’ isn’t ‘Neil of Daintree.’
You may not remember but Bjorn Borg, “Sceptical Environmentalist” found exactly the same re deforestation of tropical forests. Despite claims of widespread deforestation by the environmental lobby, an actuality, only very small areas of tropical forests had been cleared, as a percentage of the total. And tropical rainforest spreads most agressively, it is voracious in its propensity to expand and spread.
Borg got a roasting for his revelation, as is Grainger, but when the available data is examined the results are clear – there is really no basis for emotional claims that tropical forests are being lost, in terms of total area.
Slim seems to be full of contradictions “”the data is poor.” Well exactly.”, followed by (in the same sentence mind you) “certainly NOT that there is no hard evidence for decline in tropical forests”. All of this after the abstract (which we all can see at the top) states “evidence for decline is unclear”. A casual reader may wonder if some people actually read what they are commenting upon, or have a prepared argument when they see one particular word or phrase.
Thanks Paul Biggs for clarifying Lukes demise.’As you pontificated, ‘Luke’ is the pseudonym of a rather too prolific non-informative comment poster who has exiled himself from the blog following warnings about his language and conduct.’I thought he must have had his head in the sand and gone to the beach to enjoy the benign summers La Ninas sometimes bring to Australia ( not to mention cyclones etc). So you do have standards, pray tell? I thought Luke did a service by presenting a broader view of evidence on some of the more bizarre stuff aired here, and he reacted strongly to abuse from those who wanted to avoid his challenges to confront him on the evidence. Apart from his reactions, he was simply a scientist prepared to chase the evidence and be fair about it. It was Machiavelli who taught us to treasure your enemies, you surely need them to lift your game.
As I said, Luke is in self-imposed exile and he is not the only one – both sides of the arguments have been warned about standards and frequency of posting.
I still have cordial emial contact with Luke and he is not banned from the blog.
Regards,
Paul Biggs
I’m under the impression ‘Pinxi’ is banned – correct me if I”m wrong.
Mucko – the abstract states “evidence for decline is unclear”. The title of the post is “No Convincing Evidence for Decline in Tropical Forests”.
Unclear does not equal unconvincing. The author is saying that there are methodological discrepancies among studies showing decline in rainforest area which make the situation unclear. He is calling for better monitoring for more consistent data.
To spin this into some contrarian suggestion that there is no decline in tropical rainforests or even that tropical rainforest acreage might actually be increasing is disingenuous.
We don’t need to wait until all the data is in to determine whether we should be concerned for declining rainforest. Common sense would suggest that increasing global demand for rainforest timbers coupled with accelerated rainforest clearing for rotational cash cropping is diminishing the quantity and quality of tropical rainforest. A not unreasonable hypothesis. The contrarian alternative that rainforest is not declining but may actually be growing is more likely false. So as the man says, better monitoring programs will help make the situation clear.
But as the IPA receives patronage from Gunn’s it’s hardly surprising that this blog would like us to believe that the way to save rainforests is to cut them down.
NO Pinxi is not banned unless there’s a new policy to only allow posts from people who sent you a christmas card… Pinxi hasn’t been banned except that brief occasion ages ago when she got naughty to demonstrat that it’s actually impossible to ban her – all in reaction to Jen’s heavy hand (deleting tame comments from people she disagreed with but allowing and then defending comments about s-x with childrend).
Can’t you exercise some discretion of your own anyway? Commetns might be uncomfortable fo you but have hardly been inflammatory and over censorship makes no fun. I’ve just emailed Jennifer my complaint anyway. I’ve asked a couple of times why I’m being given this treatment.
Can you pls reinstate my recent posts?
ie the comments – not the complaints
“You may not remember but Bjorn Borg”
What does tennis have to do with this?
“What does tennis have to do with this?”
Erm…it’s all a load of balls???
Sorry; couldn’t resist. I’ll go flagellate myself into a penitent frenzy with a wet noodle for my sins.
Slim, you are doing that which you accuse others of doing. That is that without the data to back it you have made a claim to the effect that the rainforest is declining. To call upon “common sense” to claim that a hypothesis is fact is more along the lines of belief than science, reiterated by the ad hominem. Facts will convince others, because they cannot be refuted, not beliefs.
Paul: On the subject of Luke, I assumed he had “gone bush” or was at the beach for the duration of the holidays. At the camps and shacks round the coast downunder, political talk and hard work is taboo.
On the question of Gunns, its all quiet on the home front.
IMO Pinxi adds some colour but she needs to explore the bush more.
On the general question of deforestation It occurred to me while I was away, we need to look again at cellulose conversion to energy. Tasmania is one state that can grow a lot of wood anywhere. The recent bushfire at Snug burnt typical country side near Hobart.
The obvious process to start with is steam generation. I grew up servicing industrial boilers and ended up advising on the safety of domestic flues designed to distribute heat throughout the home. Efficient combustion and heat distribution can be home grown.
Splitting blocks for firewood saves on gym fees
We have come a long way in harnessing renewable energy. Hundreds of people witnessed several Sydney to Hobart maxis flying up storm Bay at 30 knots. Apart from the odd man overboard on the run it seems wind power too can be fun.
“That is that without the data to back it you have made a claim to the effect that the rainforest is declining. To call upon “common sense” to claim that a hypothesis is fact…”
Er..no.. That’s what I love about the commentary here – the willful misunderstanding of straightforward language. No I did not present an hypothesis as fact – I would have presumed that we all understand that an hypothesis is a working idea the scientists then set about verifying or falsifying. The basis of the scientific method and all that.
Evidence to date supports the hypothesis that tropical rainforest is declining. A more realistic working hypothesis than the proposition that tropical rainforest is increasing. Again, the title of this post is sexing up the author’s abstract to imply that there is no evidence to support the hypothesis that tropical rainforest is declining. A more careful reading indicates that there are methodological variances which make the comparison of data unclear. Better monitoring is called for. When this has happened we may then be in a better position to call the issue definitively in the way Paul is suggesting. Until then it’s just wishful and woolly thinking.
I notice Jen hasn’t posted yet on the recent results of the research project, led by Eric Rignot, principal scientist for the Radar Science and Engineering Section at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., which are appearing in the current issue of Nature Geoscience, showing Antarctica’s ice sheet is shrinking, at a rate that increased dramatically from 1996 to 2006. The mass loss increased by 75 per cent in 10 years.
I guess that doesn’t fit in with the usual story of Oslo or wherever having it’s coldest January on record and therefore there is no such thing as global warming.
Slim: “A more careful reading indicates that there are methodological variances which make the comparison of data unclear”
Several people I met on hols were involved with forest data collection and management.
I dare not challenge their methods as systems evolve to ground mere stats in R/L experience. I’m sure that on a global scale our forest reps are respected. This certainty goes back to confidence I had in our very first CEO of the AGO.
In this region we have confronted administrative cheats over the issue of permits and the gathering of logs, sustainability of wood and fresh water reserves being the long term targets.
Economies depend on truth being generated at the eyeball level.
I would think that the sight of one tree cut down may support this argument. “We don’t need to wait until all the data is in to determine whether we should be concerned for declining rainforest.” And thus a hypothesis becomes fact.
Mucko – now you’re just being obtuse and illogical. Let me reiterate for you slowly.
Concern for something does not establish hypothesis as fact. I have already refuted that specious claim. Many scientific discoveries have been made out of concern rather than simple academic interest. Many scientific discoveries are made from testing hypotheses inspired by hunches. The important thing is that hypotheses are tested with sound methodologies which can be replicated or verified by others.
As far as tropical rainforest goes there are three possibilities – it is declining, it is increasing, or it is staying the same. OK?
Previous analyses of monitoring data indicate that it is declining. So that becomes the working hypothesis. The abstract’s author says that there are methodological variances in surveys to date which make the comparison of data unclear. Better monitoring is called for. Until there is more data, preferably using comparable methodologies, the author is saying that the decline trends in tropical rainforest area remain unclear. But the hypothesis being tested remains one of decline. It can only be proved or disproved with more data. Your or my preferred opinion is irrelevant to the science.
It might be helpful to find some simple references on the scientific method if this is not clear.