Barkly Tablelands NT

The image shows some several large bushfires burning in the Barklys Tableland, in central NT. The fires here, while burning for a week or so have flared, expanding a great deal in a short amount of time. On the true colour image, the smoke plumes from these fires are quite thick, suggesting vigorous fire activity.

Rather than the more typical true colour image, this is a so-called 721 image -- a different combination of channels from the MODIS. Green is vegetation. The recent burns scars are a dark brown colour, the very recent scars or even open fires are the bright red marks. The darker coloured scars are more recent; they get lighter brown to tan to back to green as a time passes, say 1-2 years. These do NOT have the hotspots marked...they show up quite well on their own with the red and pink.

The reason for the vigour of the fires is not immediately obvious. Weather conditions are not particularly severe; no fire weather warnings are in effect. More likely, the fires have reached an area of abundantly flammable (or is it flammabley abundant?) vegetation and taken off. There was some rain (and likely lightning activity) 4 or 5 days ago in the area, and this may nave been the igniter or reinforcer of these fires.

In general, bushfire has burnt much of the pictured area (about 220 x 390 km). The NAFI fire scars mapper indicates that most of this area burnt during October...looking thru old posts, much of it looks to have been quite recently...Indeed, fuel loads are quite high across the region as a result of abundant precipitation during the past wet season. The strengthening of the El Nino often results in a delayed onset of the wet season across the NT. This means that fire activity could extend further into the year, and perhaps even into January (if fuel is available)...

Finally, these fires are burning in a remote area and are of no threat to the usual concerns. The effects will mostly be on the ecology of the region, as well as a source of greenhouse gases in the atmosphere.

Rockhampton pix

Here are a few pictures of the recent Rockhampton bushfires that from a mailing list. The photographer is unknown.

Northern Australia

The bushfire situation in much of Eastern Australia has calmed down since last weeks peak. Currently, the main area of fire is the usual activity in northern parts of the country, particularly the Top End and Cape York Peninsula.

The image (click to enlarge), a composite of two overpasses from the Aqua satellite, shows this activity. The most striking activity from this viewpoint is that on Cape York. Many are burning in and around Lakefield National Park.

Further west, several large fires are visible in eastern Arnhem Land. There are also some hotspots indicated in the Gulf Country, both near Arnhem Land and just on the QLD border.

Another large cluster of hotspots is noted just to the south of Lake Argyle, near the NT-WA border. These are burning near the Ord River. To the east of that fire, the scar from the fire near Wave Hill is visible.

Weatherwise, it has been hotter than normal across most of northern Australia. In the WA fire region noted, maximum temperatures were 40+ C. Other than that, the normal high to very high fire dangers found in the peak of fire season in the area.

In the southern part of the image, a large cloud of dust is visible. Western QLD was struck over night, and the storm has carried through much of the day (apparently from the image...), at least in southern and central NT...

Eastern QLD

Fire activity continues throughout QLD today, but conditions have moderated to some degree over recent days and firefighters are gaining the upper hand on the numerous blazes throughout the state. Conditions remain warm with moderate winds, but the higher humidity helps mitigate the fire danger.

The Mt Archer fire near Rockhampton has been contained. The approximately 100 homes that were under threat yesterday were successfully defended. The immediate threat has receded, but residents should stay alert. Fire authorities note that these fires will not be truly extinguished until it rains. Significant rain is not expected for the foreseeable future. The Rockhampton Morning Bulletin has a timeline of the recent activity in the region. Fire weather conditions do remain in the very high category in the area.

Another large fire, in excess of 30 000 ha is reported near Gaeta. This is about 200 km SSE of Rockhamtpon. Many crews from outside the area, including NSW, are being used to fight this fire. No 'property' is threatened at this time.

A brief news item also appeared today which described some of the impact that bushfires that don't threaten 'property' can have. Graziers in western central QLD reported over 50 000 ha burnt in lightning caused fires last week near Texas. Many prime grazing pastures have been lost in the area, impacting their operations. Just because suburban houses aren't destroyed doesn't mean that bushfires have no affect. All wildfire has some effect regardless of where it occurs, just not always on human values. Low-intensity fires can even have beneficial effects.

Northern Australia and more

The image (click to enlarge) shows the whole of Australia (sorry, TAS!) on 19 October 2009. The image is a composite of three MODIS images from successive overpasses of the Aqua, each at roughly 1300-1500 LT at the time the satellite is overhead. The hotspots indicate numerous areas of fire across the nation, particularly in the north.

The upper hand has been gained over much of the fire activity recently seen in QLD and northern NSW. High temperatures have moderated and afternoon humidity is not quite as low thanks to moderate easterly (onshore) winds. The widespread cumulus field extending inland shows this quite nicely. This has allowed fire fighters in NSW to gain control over most of the fires there. A few isolated hotspots are visible along the northern coast.

While many of the fires burning in QLD are now contained, the situation still remains dangerous. The Mt Archer fire near Rockhampton is still threatening homes and keeping residents on high alert. While the weather has moderated, fire bans remain in effect for much of the state through to next week.

The Top End region of the NT remains quite active. Numerous fires are visible throughout Arnhem Land. A particularly active cluster of hotspots, with a thick smoke plume, is noted in the southwestern Top End, west of Port Keats. Further south from there several large fires are also visible; these fires haven't been burning for a great length of time but have quite prominent fire scars in their wake. Breezy afternoon easterly winds, low RH and hot temperatures (upper-30s) have driven very high to extreme fire dangers across the area.

Much of the Kimberley region of northwestern WA remains quite active also. While the threat to the outskirts of Broome has receded, the fires have continued to burn in the area. Most of these are new fires, not continuations of those noted previously. The same is true in the northern part of the Kimberley; five or six large clusters of hotspots are burning. The fires further south, in the Great Sandy Desert also continue to burn. As in the NT, the air has been quite dry with moderate easterly winds.

For the eagle-eyed, some signs of activity are visible in the southern part of the country. A commercial orchard has been reported as destroyed in southwestern WA. The NASA Earth Observatory image of the day noted some thick smoke plumes in this area on the 16^th. Looking back at the subsets, smoke is visible back until at least the 13^th...A few hotspots and perhaps a thin smoke plume is visible today. Most likely these would be some sort of prescribed burning activity. Another prescribed burn is visible along the NSW/VIC border in the Moira Lake area. Another (likely) prescribed fire can also been seen in SA in Billiat Conservation Park, with hotspots and a thin plume of smoke.

Rockhampton QLD

Rockhampton QLD is facing a bushfire emergency tonight, as the fire conditions worsen for the blaze to the east of the city, in the Mt Archer area. Authorities are recommending evacuation for some the suburbs of the city, including Frenchville, Koongal and Lakes Creek. Several homes are believed to have been lost, as the fire burns erratically on a WNW course through the area.

The image is from the Aqua satellite overpass this afternoon, around 1345 LT. It is a close-up of the Rockhampton area, about 100 km across the image. The fires are quite close to Rockhampton (R). A large smoke plume is obvious, also impacting the city

Fire weather conditions remain in the very high range. The area is very dry, with little rain observed over the past several months. Afternoon relative humidities are around 10%, with moderate winds. Conditions are expected to be similar tomorrow. Fire bans remain in effect for much of QLD until at least 19 October. Extensions are likely.

At 2100 this evening, residents in some of the affected suburbs are able to return home. The situation remains dangerous and residents are advised to be prepared to enact their bushfire plans.

Pictures of the fire and the fire fighting effort are available in this photo gallery from The Morning Bulletin.

Eastern Australia + Broome

Bushfires have been threatening homes across the nation today. A summary article from the ABC provides the details.

The RFS reports three major fires in the north of state, in the vicinity of Grafton. Tow of these fires have burnt more than 1500 -2000 ha each and remain out of control. A third, smaller fire in the area is in the process of being controlled. (video report). Houses are no longer under threat tonight. Fire weather conditions are in the 'very high' range and are expected to persist through at least tomorrow. The MODIS image is from the Terra satellite overpass around noon local time. The largest fires are the northern two. Grafton, about 30 km from the coast, is at the G.

The are numerous fires burning in QLD. The most serious is to the east of Rockhampton, where fires have been burning for more than a week. This fire forced evacuations earlier this afternoon. The fire continues to burn this evening, but houses are no longer under threat. Hot temperatures, very low RH and moderate gusty winds acted to produce near-extreme fire weather conditions in today Rockhampton.

Fires continued to flare in the Kimberley region of northwestern WA. Broome saw homes threatened again today on its northern outskirts. NAFI shows that the fires there have expanded considerably since last noted. I estimate over 50 000 ha affected at this time. In general, the Kimberley as a whole remains quite active in terms of wildfire. Most of the fires noted in the region several days ago remain burning; NAFI shows their growth and evolution quite clearly. This includes the activity in the Great Sandy Desert, the Dampier Peninsula and the northern parts of the region. Fire conditions remain seasonally high and dangerous.

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Images: Broome fire: Tony Hutchinson

Climate Change and Bushfires

That climate change should have a noticeable impact bushfire activity seems obvious; large bushfires are largely a manifestation of both short-term weather and climate convolved with vegetation dynamics (i.e. fuel), itself a function of weather and climate. What is less obvious are the exact details of how this interaction will play out.

One obvious effect is on the weather and climate. In many fire prone regions, heat waves and drought are projected to become more intense and/or more frequent. These trends will obviously increase the fire weather danger, producing more days with 'extreme' fire weather conditions. More days implies more chances for fires to ignite, more chances for existing fires to spread out of control, more chances for a dramatic human impact.

Less obvious is the effect on the vegetation side of things. As the climate changes, will the same types of vegetation continue to grow in a given location? If the forest burns down, will it always grow back? What about other, less-quantified effects like CO2 fertilization?

Fire is an ecological force. The combination of fire frequency, vegetation and plant types along with the weather and climate describes the 'fire regime' of a location. What is clear is that the fire regime of places will change with the climate. This depends on the location and the exact details of the change that occurs. For example, one place may witness a change from forest to grassland, perhaps resulting in more frequent, lower intensity fires. In another case, forest persists in the face of more frequent or more severe droughts, resulting in high fuel loads and hotter, more dangerous fires. In both cases, the fire regime changes. This is what happens with climate change. Organisms that fail to adapt to the new regime die or move on, the previous character of the locale is gone forever...

There is evidence of these changes in fire regime around the world; most obvious to identify is unusual or increased fire activity. In the western USA, fire activity and cost to society has increased dramatically since the turn of the century. Athens, capital of Greece, has seen two major fires wildfires in two years. In many places around the world, there has been an apparent uptick in fire activity and consequences.

Australia is no exception. The 21^st century has to this point seen several major bushfire disasters, particularly in the southeast portion of the continent. Most recent are the events of 7 Feb 2009, Black Saturday. The Canberra bushfires were in 2003, while Victoria also saw a fire of over a million ha that year (as well as another in 2006-7...). Are these events 'caused by' climate change?

The question is difficult to answer with certainty. Some would argue that the relative lack of prescribed burning or the general incompetence of fire management authorities are to blame. There is at least a grain of truth in those arguments, at least as far as the scale of the disasters. There is also an uncertain history of fire in Australia. Fire is undoubtedly a major part of the ecosystem; the local history and mythology is filled with anecdotal tales of bushfire. But nothing is definitive; the data necessary to quantify the problem are lacking.

A highly improbable event like Black Saturday cannot be definitive of a climate change influence. We know that days with similarly outrageous fire danger scores have occurred before, for example, Ash Wednesday in 1983 was close. How often they happen is uncertain; once every 30 years or so is probably not a bad guess. These type of events occurring more frequently, say once a decade would provide more certainty. But that certainty is 20 or more years away, a long time to wait...That said, there is a tendency in the last 30 years or so towards overall higher fire dangers in many locations in Australia, particularly the southeast.

Despite this lack of certainty, I strongly believe that anthropogenic climate change is a reality that needs to be acted upon. Despite quibbles about the vagaries of the mean global temperature tendencies, there are many other independent lines of evidence. Many changes are underfoot. Globally, animal species are on the move, Ice caps and glaciers are melting, droughts are intensifying and becoming more frequent in many locations. All of these have their roots in human activity, not just climate change but other environmental misuse as well.

We know that we are making major changes our physical environment; we are changing the chemistry, physics and biology of the system. The final outcome of the Great CO2 Enhancement Experiment (40% and rising...) is not yet known, but early signs suggest that the result is unlikely to be favourable for either our civilization or the ecosystem upon which we depend. True, our action today may very well be too late or otherwise ineffective, but inaction guarantees a more difficult life for future generations.

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This post was written in support of Blog Action Day.

If you like this post, then go and read my (currently inactive) blog planet doom?. It has heaps of posts about climate change and other human effects on the world around us, There are multiple posts on wildfire and climate change available.