By Adam Morton
What is happening with fire in Tasmania?
The island state is burning in a way it hasn't for many years. Lightning strikes on January 13 sparked a series of blazes, mainly in the state's north-west. It led to the evacuation of coastal hamlets such as Arthur River and the state's famous Overland Track, and threw up smoke that could be seen across the state.
More than three weeks on, and despite some heavy rain that caused flooding in some areas, more than 70 fires are still burning. Most are in the west, where there has been less rain. The fires range from established blazes in remote wilderness to flickering hotspots.
As of Friday, the Tasmanian Fire service estimated an area of about 105,000 hectares – slightly bigger than greater Melbourne – had been blackened.
More than 20 of the blazes still burning are in the Tasmanian Wilderness World Heritage Area that accounts for roughly a fifth of the state.
Others are in or near the cool temperate rainforest of the Tarkine, which is not part of the world heritage area but is the ongoing focus of a campaign by environmentalists for greater protection.
How bad is the damage?
According to scientists familiar with the ecology of the area, bad – and worse when you consider what it suggests what might lie ahead. The destroyed area includes a part of the state's alpine central region, which has historically not burned unless deliberately lit by graziers or campers.
Two photographers, Rob Blakers and Dan Broun, hiked to the region in late January and found the fire had destroyed ancient ecosystems of pencil and King Billy pines and large cushion plants that had lived for more than 1000 years.
The world heritage area is ecologically diverse and vast, spanning nearly 16,000 square kilometres, with some areas better naturally equipped to recover from fires than others. Best estimates suggest about 15,000 hectares of this have burned this year. Only part of this is on the central plateau.
With fires still burning, it is not yet possible to fully assess the damage. A Tasmanian Fire Service spokeswoman said fire continues to burn near Lake Mackenzie on the central plateau at an altitude of about 1200 metres, near where Blakers and Broun took their pictures. A separate blaze is alight in the Walls of Jerusalem National Park.
Part of the south-west wilderness, some of which is incredibly remote and difficult to reach, is also burning.
How long will it take to recover?
It depends on which area we are talking about.
On the central plateau around Lake Mackenzie, the question is whether it will recover at all. The alpine ecosystem there is unique, and a throwback – part of what fire ecologist Professor David Bowman says is a "geological refuge" in western Tasmania that has survived since the time of the supercontinent of Gondwana. While there are ancient ecosystems in other parts of what was once Gondwana that survive in a climate similar to Tasmania's west, none are the same. It does not regenerate after fire in the way a eucalypt forest does. When it is lost, it is likely to be lost for good. If it does recover, it is likely to take more than a millennium.
Tasmania's endemic temperate rainforest isn't designed to burn either. It tends to be replaced after fire by eucalypt forest, and can take between 600 and 800 years to return to a more pure rainforest of myrtle beech, leatherwood and sassafras.
Surely this this not the first time these areas have burned?
There have, of course, been fires in the world heritage area before. As recently as January 2013, a blaze near Giblin River in the south-west wilderness beat a path through 45,000 hectares.
In the western alpine region, fires were extremely rare before the arrival of Europeans. Since then there have been a number of fires, lit both accidentally and deliberately, that have significantly reduced what's left of the unique ancient Tasmanian flora. They have slowed since 1982, when the area was declared world heritage and campfires were banned.
Why do these fires have scientists so concerned?
The scale of the fires is enough to spark concern, but it is the conditions under which they started that has experts most worried. The past decade has seen a significant increase in the number of blazes caused by lightning strikes, with the 2013 Giblin River fire an obvious example.
The January 13 lightning storms hit forests that were ready to burn. Western Tasmania had the driest spring on record, and the summer has been hotter than average, with many sites setting new benchmarks. Scientists attribute this to an El Nino in the Pacific Ocean exacerbating the long-term warming trend the planet is experiencing due to the emission of heat-trapping greenhouse gases. They have also warned that climate change will lead to an increase in lightning strikes.
In other words, while there will always be year-to-year variation, these conditions are expected to occur more frequently in future.
Professor Bowman last week told Fairfax Media that he was now deeply concerned about the survival of the state's unique alpine ecosystems. "I think I would be being unethical and unprofessional if I didn't form the diagnosis and say what it is – climate change," he said. "Under the current rate of warming I think this ecosystem will be gone in 50 years."
What can be done?
With fires still burning, the discussion about what, if anything, should be done to improve protection of heritage-listed landscapes has been relatively muted.
Some scientists and environmentalists have expressed concern that authorities – particularly federal agencies that can swing in and help states in times of disaster – are too slow to defend world heritage and other protected areas. They stress the first focus should be saving lives, but argue places of international significance should given as much or more weighting as protecting property that can be rebuilt.
Authorities strenuously deny they have been slow to protect highly valued forests, pointing to more than 30 aircraft dropping water on Tasmania's wilderness, and strike teams that are being sent into forests in a bid to deal with hotspots detected from the air before they burn.
Professor Bowman suggested it may be necessary to start collecting genetic material from threatened ecosystem species to ensure they do not go the way of the thylacine.
All say there will be a proper review once the fires are out. That may be a while yet.
