august 2013
Philip De Bruyn lights a research burn that will later be correlated to fire intensity mapping provided by MODIS satellites. (Photo: Ron Steffens.)

A map is a mark of our lives in time, a journey transcribed. And it was a map, in part, that drew me to Australia, to better understand what fire maps can mean in our climate-change era, and to learn how a robust commitment to geospatial knowledge can help us manage what may be our most hazardous and valuable resource – the carbon that’s either released or sequestered in every fire-affected forest, bush, savanna and grassland.

My own journey, by jet, train, bus, Land Cruiser and helicopter, burned a carbon debt I’ll work most of my career to pay back. In the fall of 2012 I flew some 14 hours across the Pacific Ocean from the United States to Australia, then four hours from Sydney to Perth. After the Australian Fire Authorities (AFAC) and Bushfire CRC meeting, I flew north to Broome, the west coast gateway to mining, tourism, and the aboriginally managed lands. From Broome, I was driven northeast via Land Cruiser by Philip De Bruyn, the fire planning coordinator for the Kimberley Ranger Program. We bounced through red dirt and the squat gum forest, past wallabies and cattle and free-roaming fires and into the sandstone and red-rimrock country of the Kimberley, one of the more remote parts of a continent that gave us the type specimen for “outback.”

I had other reasons to travel this far, but this particular leg of a larger journey was inspired by a map I’d first seen in a talk at a fire conference in South Africa; it conveyed information on the North Australian Fire Information (NAFI) website and network. I needed to witness firsthand what anyone with a computer and slow Internet connection can observe from afar: that the Australian bush burns every few years (even every year), and it burns wide and far across the land.

The NAFI maps were telling the diurnal and seasonal story of man and fire across a big land. This was the smell of smoke to a smoke-chaser. To know fire you must know Australia, and NAFI seemed the tool to guide us to where cutting-edge science meets our original fire-stick tool.

It’s a familiar story: the bush has burned across the epochs of evolution and fire adaptation that predates human timekeeping – the first people here walked with fire sticks, and before them (and today) the pre-monsoon lightning ignited the landscape. Now, as the fires burn, we can watch the heat signature progress in near real-time, thanks to satellites and the calibration and mapping work of the fire researchers and practitioners I was joining in the bush.

The carbon burns and out-gasses into the sky. Yet if we manage the fires, return to less frequent and patchier cool-season burns that steal the fuel from hot late-season burns, we can conserve the carbon in the soil and roots, in regenerating bush and resilient trees. This is what we know to do and are doing, thanks, in part, to teams of researchers and practitioners like those I’m traveling with, who ensure that tools like NAFI pull the satellite data down in order to serve the needs that grow from the ground.

The burning bush

After the day’s drive, we meet with the rest of the team members to camp at a wet billabong near Karunjie. They’ve come from the opposite side of the outback, a day-and-a-half ’s drive from Darwin at the north-central top of the continent.Andrew Edwards, a research fellow with Bushfire NT and the Darwin Centre for Bushfire Research at Charles Darwin University, had invited me here after we’d chatted at AFAC. He shakes my hand and asks, “So Ron, what’s your question? Why are you here?” My question? De Bruyn, with whom I’d chatted for hours, suggests my deeper motive: “To have a good walkabout in the Kimberley?”

To which I agreed, though I did offer a purpose – to see, first-hand, how the science and practice are coming together – to see how fire science, applied fire and carbon management can support each other as we face the challenge of climate change. And to see it on the ground, to better apply these lessons elsewhere.

For the next few days and later, in Darwin and by Skype, Edwards and colleagues, including Peter Jacklyn, the NAFI web architect, explain the details of the science and resulting scheme (which is a word, outside the U.S., that lacks our illicit sense of underhandedness). When early cool-season burns dominate, the burns are patchier; less litter is consumed, and less of the grass and bush biomass, so that the grasses re-sprout and scorched eucalyptus starts to bud and leaf out before the dry season stunts the growth, thus drawing carbon from the atmosphere into the biomass. This compares to a late-season burn, which out-gasses more carbon and begins, over time, to convert the resilient bush into over-dominant exotics, which are, in turn, more flammable, and the carbon sink degrades.
To reach the point where NAFI can support a carbon scheme, three key questions had to be answered, by fuel model and habitat type, and by early and late burns:

  1. The CO2 emissions released
  2. The emissions conserved
  3. The emissions sequestered

The potential for carbon sequestration in the tropical savanna is based on definitive research by Jeremy Russell-Smith, Peter Cooke and others that concluded that the carbon sequestration can occur in fire-managed savanna that receives more than 1,000 mm precipitation a year, as does the northern tier of Australia.

The tropical savanna covers some 12% of the globe and is one of our richest sources of carbon sinks and biodiversity. This week, though, we were seeking to expand the original premise: can lower rainfall sites, from 600-1,000 mm, also sequester carbon, if we burned smarter.

So it was time for the research teams to re-measure old burns and to light new hot-season burns. For this scheme to work, you need 10 years of prior baseline burn data, plus this sort of field and satellite work to determine fuel accumulations. Finally, you can start to measure each year’s savings, by comparing a year in which you’re managing fire (for carbon and biodiversity and cultural values) against the earlier years. You need horizontal burn patchiness and vertical impact of scorch height. You need to sample from soil to grass/herbs to shrubs and trees, from fine to course fuels. And you need to confirm this on foot and by helicopter to correlate it to the satellite data, all of which feeds the NAFI maps.

The process is based on tallying “Burning Efficiency,” a formula that multiplies “Patchiness” by “Combustion Completeness” to calculate your greenhouse gas emissions. Building on decades of work, the team has determined that fire seasonality can become a proxy for and key mechanism that, when combined with Moderate Resolution Imaging Spectroradiometer (MODIS) data, can yield a robust and real-time tool for fire severity mapping. Edwards et al are working on a model for a Normalized Burn Ratio (combining seasonality with MODIS and other tools) that’s nearing 94% accuracy for mapping severity, compared with 50%-60% accuracy with MODIS alone. The result is that you can press a few buttons on a NAFI map to generate a seasonal and annual burn report, which can help you interpret the key impact of burn seasonality: that early season burns have from 10%20% more patchiness and 10% less combustion than late-season burns – which equals carbon sequestered.

This process, intuitive as it is complex, is why I found myself helping to ignite research burns in the Kimberley in early September, the start of hot season burns. The team was seeking to fill the data gaps, to measure what burns and what remains, to compare with the earlier cool-season burns and measure the comparative impacts on both biodiversity and carbon sequestration. This is a form of valuation, as key to climate’s health as depositing a paycheck in a bank machine.

De Bruyn drags the torch for these burns and I’m running ahead to scout a good line. We turn the corner and De Bruyn’s drip torch hooks the head of the fire and we both stop, breathing equally hard. Then we turn to the fire to take photos of the flames, which crackle with an occasional internal whoomp as the ground fuels ignite a tree’s canopy. We catch our breath and then take fire back to the gravel road where we started. Most of the burn’s intensity has cooled within 10 minutes. The grasses and forbs and the lower leaves of the trees are burnt to nothing. The upper leaves are singed but alive, and in a week, the basal roots and stems will be flushing green.

A small finger of fire burns in 5-foot flames across the road. In the interior, the flames have crossed our burn line. I ask, “Should we put this out?” No, I’m told, this fire will burn out in the evening’s humidity or when the fires reach an area that’s been previously burnt out. And we think it does, which we can confirm, by satellite, via a low-bandwidth NAFI download via a sat-phone. Two days later, on a helicopter flight to map burn severity to the southeast, we do see a column suspiciously near our research burn; but as we fly, we determine that it’s further west than our fire.

From space to place

Fast and shiny satellites track our skies night and day, but an effective satellite-based fire mapping program doesn’t just drop from the sky.

If a fire burns in the forest or the bush or the veld, if it’s hot or large enough, a MODIS satellite will record the heat signature. Every six hours, if conditions are right, we can spy where the hotspots are heading and if the fire’s burning hotter, colder or not at all. And once the burns are ground truthed and melded into GIS formulas with “ecognition” software, one can determine high-severity canopy burns from low-severity ground burns, as well as patchiness, which altogether can help to quantify and certify the carbon-added value.

This is MODIS’s gift of good will, the freely streamed data that’s shaped fire detection and mapping globally. “We would have absolutely nothing without MODIS,” Edwards says. “It’s our meat and potatoes. Without MODIS, fire management would take big leaps backward.”

What NAFI has accomplished with this NASA-launched and maintained gift of data, though, is to ensure that the data answered the questions that the practitioners on the ground needed answered, serving the lands of a huge country with large, slow-moving burns and few management resources. Without MODIS and NAFI, land managers would be burning days of time in a truck or “thousands of dollars a day of chopper fuel that they didn’t have to use” to track their fires.

Now, each morning, they log into the computer and check NAFI. What’s burning, where’s the fire burning toward, is it burning into older burns (and lighter fuels) or burning toward values that need protecting – all with a low-bandwidth connection and an interface that remembers who you are and what you want to watch.

A NAFI study estimates $2 million in savings each year, for a program cost of one-sixth that amount. It’s estimated that regional indigenous communities earn $1 million per year in benefits. The program has just been renewed, with $1.2 million of support for five years, with a new website planned to launch soon as well as added support for Australia’s Carbon Farming initiative.

Oddly, though, the NAFI success may be due, in part, to an initial lack of resources. As Jacklyn notes, “There are such limited resources in the Northern Territory that there’s a tendency to agree if it meant you could get some more resources. And, we were all facing common problems across the north.”

Edwards notes that one component that helped launch NAFA was “the early focus on low bandwidth delivery of a very simplistic map.”

Jacklyn agrees: “People wanted something simple. People just wanted to know where fires are and where the burnt country is, in relation to them.”

“With NAFI,” Edwards adds, “in seconds they’d know what they’d have to do that day. You look out and see smoke on the horizon, and you know, is it smoke I need to worry about?”

The NAFI website offers two kinds of knowledge: on the land management side, the rangers can judge the success of their burning and “use it to iteratively monitor and target areas you need to return to. But then the data from NAFI can be used for the carbon abatement program…it’s a legally recognized measurement.”

While NAFI, as a model, offers technical, social and economic lessons, its success required hard work and a dedicated sponsor; a network that offered creative and strategic leadership that also listened to what was needed in the field; and, as Andrew noted, “Someone to sell the program.”

From its initial pilot in 2003, the NAFI program needed to design a website, invent and manage a GIS system, measure pre-and post-burn sites, both build and offer ongoing support for aerial and ground ignitions and ground-based suppression rangers, and run helicopter transects to correlate burn severity with the satellite data.

Which brings up one of the more challenging questions for NAFI’s future, and for all fire mapping: the entire program depends on MODIS data, which is produced by an aging satellite system with a delayed replacement. There is talk of new solutions – the crowd-sourcing of next-generation $50,000 satellites – but for this season (and for how many to come?), we rely on satellites that were expected to fail years ago.

After the flames

Anywhere a fire burns or has the potential to burn, someone is likely to be monitoring this elemental process. Some fires are observed simply by their carbon exhaust, a measurement that implies future management, just as we now measure though don’t yet manage so much of our personal and industrial carbon exhaust. We may measure the acres burned as either resources or homes lost, or rejuvenation, or carbon sequestered or saved or lost. Whatever our rationale for measuring, it is comforting that we have those who’ve spent a decade (and more) perfecting this craft.
Perhaps this is the take-it-to-thecarbon-bank lesson we can draw from the NAFI mapping program: that real-time mapping can shape the strategies and responses we apply today.

By mapping the early burns and fuel breaks, we can manage the later burns.

The maps connect the projects, the funders and on-the-ground managers and the scientists. The maps are knowledge, but they’re nothing without the relationships that build the maps – and together, they can be traded – for hard cash that can support community fire-management partnerships, a cadre of rangers, the helicopters trailing aerial firesticks, and data-inspired management protocols – that again, taken together, can help to support a rich culture and biodiversity where both are at risk. All because a satellite’s eye can be taught to convert the remotest fire into a pixel.

That was my question: to learn how to burn fires early and cooler, to maintain more carbon in the soil and the unburnt plants, and to map the fuel breaks that these early fires hold against the late fires. This is why I traveled to the Kimberley – to learn to map the hotspots and ash that may conserve a bit of carbon and balance the hot-fires and carbon exhaust that now shape our fire regimes and livelihoods.

Conserving carbon

After a week in the field, I debriefed with Edwards in NAFI’s Darwin lab, part of Bushfire CRC and now housed within Charles Darwin University. We clicked through screens of fires burning and burn scars in Arnhem Land and the Kimberley and Cape York and Kakadu National Park, a free-burning land from the height of space. One can click on pre-set zones and instantly collate a PDF report of fire’s impact and benefit. The savanna and bush move from green to brown to black and then f lushes green again.

This is the power of a system that applies global tools for global solutions while drawing on local feet-on-the-ground skills that offer local solutions.

This is the optimism being crafted in North Australia – where a burn (and its representative pixel) can be both the fire and a potential salvation from our carbon-fires, where fire is both a tool for local development and a bank for global carbon. But optimists must smell the smoke, too. Fire intervals need to lengthen; fire intensities need to drop.

Edwards pulls up the day’s hotspots on the map, here in the hot season when more carbon is outgassed than can be sequestered in return. Fires dot the NAFI screen red, like digital measles. “The carbon we’re unlocking is ridiculous.”