Reviving the West Arnhem Plateau

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

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).

NAFI Scars

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

 

 

 

 

 

 

 

 

 

 

 

 

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

WALFA chopper

Researchers and young men from a community near the plateau measure the impact of fire using aerial surveys

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 CO2 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.

 

DLNG

The Liquid Natural Gas refinery operated by DLNG in Darwin



 

 

 

 

 

 

 

 

 

 

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