By the early 2000s the West Arnhem Plateau’s Indigenous
leaders like Wamud Namok, together with fire managers and
researchers, could see that if wildfires on the plateau could be
reduced by strategic early dry season burning, we could have a
“win-win” situation – anthropogenic greenhouse
emissions would be reduced and damage to biodiversity and cultural
values would also be lessened.
Added to this was the third important win – companies that
emit greenhouse gases are willing to pay significant sums to offset
these emissions by funding schemes that abate human caused
emissions. So here was a potential income stream for people who
were best placed to control wildfire: the local indigenous
communities who had done this in the past by lighting patchy fires
throughout year. Such funding could not only lead to reduction in
Greenhouse Gases but could also provide long-term support to tackle
the problems of Indigenous disadvantage and biodiversity decline in
Western Arnhem Land.
What is strategic early dry season burning?
Fires in north Australia behave differently depending on the
weather conditions and the moisture status of the fuel (grass,
leaves and wood) that is available to burn. Fuel and weather vary
more or less predictably throughout the year:
Wet season, usually January – April: there is
plenty of fuel around but the heavy rains and waterlogged
conditions mean fires do not start or spread easily.
Early dry season, usually May –
July/August: the grassy fuel is still moist following the
wet season and the generally cooler temperatures, dewy mornings and
light winds mean that fires that do occur are usually patchy and
often go out at night.
Late dry season, usually August– December: grass
and litter become tinder-dry and it is typically hot, dry, and
windy during the day. Fires can spread quickly, burn through the
night and, under severe fire weather conditions, become intense and
extensive wildfires. They can defoliate tree canopies and consume
even solid woody debris.
Strategic early dry season burning involves a mix on on-ground
patch-burning lit by people on the ground and larger scale fire
breaks lit along tracks, rivers and creeks from helicopters –
all carried out between April and July. This breaks up the
landscape and makes it more difficult for wildfires to spread
across the fire breaks later in the year. With strategic breaks in
place it becomes more feasible to burn later into the year if
required.
Using Two Tool-Kits
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The Community
at Kabulwarnamyo in the eastern Arnhem Land Plateau which has
played a major role in the WALFA project
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How can this strategic burning be implemented across a rugged
landscape the size of a small European country? In traditional
times many people would have managed the plateau country, but today
this would have to been done with a few dozen people from
Indigenous ranger groups, many based in settlements surrounding the
plateau.
So a “two tool-kit” approach to fire management was
developed which combined traditional skills and knowledge with
western scientific practices and technology. As well as creating
small patchy burns using traditional skills, the Indigenous Rangers
rapidly established fire breaks over a hundred kilometers long with
the help of helicopters and aircraft.1
As well as gauging the effectiveness of burns using their intimate
knowledge of the bush, rangers also used satellite information to
track the course of fire burning over the horizon using a website
created for northern fire managers (www.firenorth.org.au).
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A map from the fire-tracking website
(www.firenorth.au) showing
patchy fire scars (in green) already put in place in 2008 in the NW
of the plateau. The stars show burning fires as Indigenous Rangers
aim to join up a number of smaller scars to form a barrier to
protect the plateau from wildfires coming from the east
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Measuring emissions in a big country
A second issue was how to accurately assess the quantity of
Greenhouse Gas emissions abated through wildfire management. Unless
this could be credibly and reliably gauged, it was unlikely that
any abatement would receive financial backing. To do this all the
vegetation types on the plateau needed to be mapped and their
emission characteristics, when they were burnt by fires of varying
intensity, needed to be established: How much biomass was burnt?
How efficiently were they burned? What quantities of accountable
(CH4, N2O) greenhouse gases were emitted? And every year after the
fire season the extent and degree of burning needed to be
established and the consequent greenhouse emissions calculated. And
all this needed to be done over a vast area.
To do this, sophisticated remotely-sensed mapping technologies
were developed using neural network software, combined with
efficient on-ground monitoring. In 2004 these techniques
underpinned a new methodology for Greenhouse Gas emission
accounting that was accepted by Australia’s National
Greenhouse Gas Inventory.2,3
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Researchers and young men from a community near
the plateau measure the impact of fire using aerial surveys
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The results from these techniques indicated that on average 40% of
the West Arnhem Plateau is burnt each year by fire: 32% by late
season, typically intense wildfire and the remaining 8% by cooler
early fires (refer to graph above). If these numbers could be
shifted so that only 20-25% of the plateau was burned by wildfires
each year then annual emission reductions equivalent of at least
100,000 tonnes of CO
2 could be made – the
equivalent of removing around 20,000 cars from the
roads.
4
Making it pay
Finally, who would pay for this new way of reducing greenhouse
gas emissions? At around the time these emission reduction
techniques were being refined, the Northern Territory Government
started negotiating with Darwin Liquefied Natural Gas (a consortium
involving ConocoPhillips) the developers of a large LNG facility in
Darwin harbour. Both parties were looking for a way in which some
of the greenhouse gas emissions from the new plant could be
“offset” by initiatives that reduced emissions and the
NT Government proposed that the West Arnhem Land fire abatement
project be funded by DLNG as a way of achieving these offsets. In
late 2006 DLNG agreed to pay Indigenous land managers over $1M a
year (indexed for inflation) for the next 17 years to reduce
wildfires in return for recognized GHG emission reductions.
The Australian Government has sanctioned this arrangement subject
to the project meeting agreed auditing protocols.
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The Liquid Natural Gas refinery operated by DLNG in Darwin
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References
1. See ABC-TV Catalyst Program Carbon Country (2006)
http://www.abc.net.au/catalyst/stories/s1769056.htm?site=catalyst
2. Meyer CP. (2004) Establishing a consistent time series of
greenhouse gas emission estimates from savanna burning in
Australia. Report to the Australian Greenhouse Office,
Canberra. CSIRO: Melbourne.
3. Russell-Smith J, Murphy BP, Meyer CP, Cook GD, Maier S,
Edwards AC, Schatz J and Brocklehurst P. 2008. Improving estimates
of savanna burining emissions for greenhouse accounting in northern
Australia. International Journal of Wildland Fire (in
review).
4. Assuming an average annual emission of 5 tonnes
CO2e per vehicle, however, average vehicle
emissions have been estimated at less than this figure, e.g. see
http://www.bendigobank.com.au/public/generationgreen/carbon_offsets/index.asp
