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.
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.
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.
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.
"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.
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.
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.
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.
"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.