Glen Paul: G'day, and welcome to CSIROpod. I'm Glen Paul. We know the world's forests remove carbon from the atmosphere, but up until now we didn't know by just how much. New research has revealed that the world’s established forests remove 2.4 billion tonnes of carbon per year from the atmosphere, equivalent to one-third of the current annual fossil fuel emissions.
The findings were recently published in the Journal of Science, and joining me to discuss it is CSIRO co-author of the Paper, and Executive Director of the Global Carbon Project, Dr Pep Canadell. Pep, it’s clear then that forests certainly are great carbon sinks, so is it just a matter then of preserving forests, or perhaps growing more trees?
Dr Canadell: What we've shown is that what we have is exceptionally valuable as a carbon sink that is removing large amounts of carbon dioxide from the atmosphere. Another matter would be the implications of extending those forests, and of course the implications are for other needs that we have for land, from recreational, to food production, and bio fuel production.
Glen Paul: And that would obviously involve some form of logging. Just how much impact does that have?
Dr Canadell: Yeah, so basically the 2.4 billion tonnes of carbon is what established forests are doing for us. You know you can see this thing is an incredible ecosystem service as it cleans the atmosphere from anthropogenic carbon dioxide. Now, there's another side of the coin which is those parts of the world where forests are being cut down, and therefore there are large emissions.
So the study also calculated those emissions, and we found to our surprise that the emissions were much larger than we had ever actually measured or anticipated, and that was because we were able to what we call now attribute two critical fluxes of carbon; one is the one leaving from the forest into the atmosphere, but then there's a lot of forests which are abandoned after being deforested and we measured also large carbon sinks from regrowing forests in regions where it had been cut down or abandoned after those kind of degradation activities.
Glen Paul: OK. So regrowth does work as a sink, but with the deforestation in the first instance are we talking figures that are comparable to emissions from fossil fuels?
Dr Canadell: Yeah. So critical figures are first the deforestation is about three billion tonnes of carbon total, and last year fossil fuel emissions were nine billion tonnes, so there's a humungous flux coming from cutting trees. So that tells us one thing, is that even we’re to implement any sort of policies to slow down deforestation, because this flux is much bigger than what we thought, the benefits of it can be ripped out from those policies are much larger.
Glen Paul: So does that mean that the UN backed Reduced Emissions from Deforestation and Degradation scheme, or REDD, is flawed in formulating a financial value for the carbon stored in forests?
Dr Canadell: No. No, no. So basically the data what it does is actually it does support that the REDD process is a really good process, it does tell us that what's there for basically benefitting is even bigger than what we thought, but also the data points out one particular issue that is being missed in the REDD scheme, and that is the protection of the tropical re-growing.
So this component, the re-growth that comes from previously cut down areas, it’s not part of what REDD is looking at, and we’ve shown that is a humongous carbon sink, as much as 1.7 billion tonnes of carbon, again a large number compared to nine billion tonnes of fossil fuel emissions per year. So we’re saying that we could even reap larger benefits from a climate point of view if we were to also emphasise the protection of tropical re-growth.
Glen Paul: Hmm. What can be done then to ensure that rainforests are seen as being worth more alive than dead?
Dr Canadell: Well, I think that the REDD process within the UN, from a conventional climate change is actually doing the right thing. Now the issue here is how much we’re going to value the avoided tonne of carbon dioxide into the atmosphere. Is it going to cost $30 a tonne? Is it going to cost $40 a tonne? Is it going to cost $100 a tonne? And I think that every country will have to run their own economics just to understand whether, as you said, those forests are more valuable standing up than dead – currently it’s the other way around.
Glen Paul: OK. So then with deforestation, how do you encourage countries that don’t already do so to re-grow forests?
Dr Canadell: Well I think that the important thing is that the REDD scheme provides enough incentives, or fundamentally enough money for countries to look for alternative ways to have a living, that do not involve getting rid of the forests. So for instance, Brazil is looking at awarding to forestry industries that would still be using some of the wood, would still be using some of the products that come from the forest, to do production at an industrial level which would creating odd jobs for people not to have the need to go and cut down the forest, and by creating this new circle people would then have the most interest to preserve/conserve the forest for sustainable industry, both timber and forest products.
Glen Paul: Hmm, OK. Now just getting back to the science then, how were you able to come up with these sink figures?
Dr Canadell: Well, as always we do one of these global assessments, you really need to establish the appropriate international consortium so we had 12 partners from around the world. People who have fundamentally developed their science to measure millions of trees through forest inventory programs, or in many countries experts from northern latitude forests, experts from the temperate world, and experts from the tropical regions, and over a two year process we were able to bring all the data together and do all the analyses, and most importantly to identify all the gaps, which kind of prevent us from closing the entire assessment, and come up with both assumptions and new data that would help us to finish a comprehensive, for the first time ever, global assessment on the role of old forest land on the carbon cycle.
Glen Paul: And does this research fall under the Global Carbon Project banner?
Dr Canadell: Yes. So basically what we've done is that we brought this group together to contribute to what we call an attribution of the global carbon budget. We do the global carbon budget every year, and so what we’ve done with this new group is to be able to attribute a critical carbon flux in the budget which we didn’t know exactly where it was coming from. For instance, we know that the global land needs to be taking about 2.5 billion tonnes of carbon per year. We didn’t know exactly where, and which ecosystems around the world were taking that carbon.
Of course we knew that forests have a dominant role in removing carbon dioxide, but we didn’t have the numbers. Now with this new research, what it's telling us is that 2.5 billion tonnes of carbon that the land must take so that we can actually close the global carbon budget properly are coming fundamentally from forests. Other ecosystems may have a role, but some ecosystems may be a small carbon things, other ecosystems may be a small carbon sources, they all more or less balance out, and really the ecosystem that is doing the job at removing the CO2 is actually the forests from around the world.
Glen Paul: So there’s still a bit of research to be done on the various types of forests. How are you going to achieve that?
Dr Canadell: So basically the biggest gaps, or the largest uncertainties still remain in the tropics, and the tropical forest, it’s really important – it is actually the largest sinks, and the largest sources, so that’s where the biggest effort needs to go because any further constraining of the values in this part of the world constrains the entire carbon budget.
So we are working now with a number of groups, particularly now from Australia for South East Asia, and South Asia, to be able to bring new expertise into this consortium and to be able to bring new data and further constrained datasets.
Glen Paul: OK. Well, I think that on reflection no matter where you might be in the world, it’s probably a very good idea to get out there and plant a tree or two. Thanks for discussing the research with us, Pep.
Dr Canadell: Thank you very much.
Glen Paul: Dr Pep Canadell. For more information find us online at csiro.au. You can like us on Facebook, or follow us on Twitter at CSIROnews.
