Wild Wollemi pines, are they really burnt?

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Re: Wild Wollemi pines, are they really burnt?

Postby north-north-west » Fri 17 Jan, 2020 12:11 pm

This is why it never pays to play chess with pigeons.
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Re: Wild Wollemi pines, are they really burnt?

Postby duncanm » Fri 17 Jan, 2020 1:12 pm

how droll.

I see no reason, logic or evidence; just blind belief that the very brief recorded history we have is somehow unique
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Re: Wild Wollemi pines, are they really burnt?

Postby potato » Fri 17 Jan, 2020 3:27 pm

duncanm wrote:how droll.

I see no reason, logic or evidence; just blind belief that the very brief recorded history we have is somehow unique


Fascinating.

I'm a big fan of evidence and the rainfall record suggests this drought is rather unique. The tree ring record might show similar droughts but the detail isn't there to verify the severity of droughts recorded there. In addition, the spatial extent of the fires, to my knowledge of at least the Holocene record, is very unique.

Its obvious that fires have been through these areas before but I thank NSW Parks for getting out there in these gullies to have a go at protecting the wollemi pine ecosystems.
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Re: Wild Wollemi pines, are they really burnt?

Postby LachlanB » Fri 17 Jan, 2020 4:08 pm

https://www.researchgate.net/publicatio ... 6/download

It's probably behind a paywall (I don't know because I get institutional access). But the graph on p440 suggests that contemporaneous charcoal levels in Goochs Crater in the Blue Mountain are higher than they have been at any point in the last 14,000+ years. Granted, the charcoal in previous peaks could be from single fires or collections of smaller fires, but it seems pretty obvious that fire activity is currently higher than average.

Plus (it's not the Blue Mtns, but similar enough), this Guardian Australia article (https://www.theguardian.com/australia-n ... nous-sites) quotes a Yuin man saying: “These are the worst bushfires in our history, it’s never gone up like this. Our people never knew fires like this. The ancestors would be wild, I reckon, about what’s happened to the country, to our totem animals. There are hundreds of sites, male ceremony places, sites on our sacred mountain, that burned. Not only Yuin land but all over – there’d be thousands of places destroyed by these fires.”

Add to this knowledge of how climate change intensifies natural disasters, and the lack of any similar fire events recorded in European history in Australia, I think it is pretty safe to say that this current fire season is unprecedented. I don't think it is arrogant to say so, just realistic.
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Re: Wild Wollemi pines, are they really burnt?

Postby highercountry » Fri 17 Jan, 2020 4:59 pm

...
Last edited by highercountry on Sat 18 Jan, 2020 1:11 pm, edited 1 time in total.
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Re: Wild Wollemi pines, are they really burnt?

Postby boronia » Fri 17 Jan, 2020 5:37 pm

LachlanB wrote:
wildwanderer wrote:Nice story with video on smh.com.au on the battle to save the pines over this fire season.

Only thing I'm a bit wary of is they show aerial shots of their location featuring some distinctive topography.

Hopefully the aerials are not wide enough for some bright spark to begin examining topo and sat maps and then speculate to the pines location on social media.


Hmm, is it just me, or has one of the aerial piccies disappeared since the other day? The one with the burnt T-shaped valley, and this guy checking the small pine (https://www.facebook.com/NSWNationalPar ... =3&theater) improbably Photoshopped onto the cliff-face?


They're all still there in the dropbox - https://www.dropbox.com/sh/qhnuxln4sy74 ... gctDa?dl=0
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Re: Wild Wollemi pines, are they really burnt?

Postby duncanm » Sat 18 Jan, 2020 7:55 am

LachlanB wrote:https://www.researchgate.net/publication/240738344_Implications_of_a_14_200_year_contiguous_fire_record_for_understanding_human-climate_relationships_at_Goochs_Swamp_New_South_Wales_Australia/link/556cef5e08aec22683054a56/download

It's probably behind a paywall (I don't know because I get institutional access). But the graph on p440 suggests that contemporaneous charcoal levels in Goochs Crater in the Blue Mountain are higher than they have been at any point in the last 14,000+ years. Granted, the charcoal in previous peaks could be from single fires or collections of smaller fires, but it seems pretty obvious that fire activity is currently higher than average.


possibly. Its like the arrival of humans in Australia 40k+ years ago. There seems to be a fair bit of debate in the literature regarding the change in fauna from wet rainforest type plants like Araucariaceae to more widespread sclerophyll forests as recorded in the charcoal and pollen records - did the Aboriginal fire practices change the landscape, or was it already well on its way due to the changing climate?

Plus (it's not the Blue Mtns, but similar enough), this Guardian Australia article (https://www.theguardian.com/australia-n ... nous-sites) quotes a Yuin man saying: “These are the worst bushfires in our history, it’s never gone up like this. Our people never knew fires like this. The ancestors would be wild, I reckon, about what’s happened to the country, to our totem animals. There are hundreds of sites, male ceremony places, sites on our sacred mountain, that burned. Not only Yuin land but all over – there’d be thousands of places destroyed by these fires.”


This I would completely agree with -- but is his anger directed at the changing climate, or the changes in land management practices? You left out an important quote from that article:
“This might be a wake-up call for them now to listen to us Indigenous people on how we do our cultural burning. It’s time to ask us how to look after the country.”

Add to this knowledge of how climate change intensifies natural disasters, and the lack of any similar fire events recorded in European history in Australia, I think it is pretty safe to say that this current fire season is unprecedented. I don't think it is arrogant to say so, just realistic.


Unprecedented in our lifetimes yes. In our (European recorded) history, maybe (but 1851 and 1939 say otherwise). Prior to that, I question.

The real point is - what do we do about it? Would the NPWS hit-squad have been better used squashing the Gosper's mountain fire at its source, rather than concentrating on the Wollemi pine grove?
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Re: Wild Wollemi pines, are they really burnt?

Postby north-north-west » Sat 18 Jan, 2020 5:14 pm

duncan:

Are you questioning whether climate change is really happening, whether it is principally due to human activity, or whether we should actually try to do something about it? Or just muddying the waters by insisting on "hard scientific evidence" of what the climate was, worldwide, when Wollemi Pines first evolved, and what changes they have endured since?
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Re: Wild Wollemi pines, are they really burnt?

Postby ribuck » Sat 18 Jan, 2020 5:21 pm

duncanm wrote:Would the NPWS hit-squad have been better used squashing the Gosper's mountain fire at its source, rather than concentrating on the Wollemi pine grove?

Well, no. Because then the next fire could be even bigger and hotter. With things as they are at the moment, I can't think of a better policy than "Let it burn, frequently, and do what's practical to protect the most valuable things."
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Re: Wild Wollemi pines, are they really burnt?

Postby Neo » Sat 18 Jan, 2020 6:09 pm

A patchwork of cooler low intensity burns sounds like the go.
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Re: Wild Wollemi pines, are they really burnt?

Postby duncanm » Sun 19 Jan, 2020 9:17 am

north-north-west wrote:duncan:

Are you questioning whether climate change is really happening, whether it is principally due to human activity, or whether we should actually try to do something about it? Or just muddying the waters by insisting on "hard scientific evidence" of what the climate was, worldwide, when Wollemi Pines first evolved, and what changes they have endured since?


We know pretty well what the climate was like when the Wollemi Pine evolved. Hotter, much wetter, and much more CO2 than now.

What I'm questioning is the assumption that they have not experienced and survived similar fires in the past. They are a genus which has existed for millions of years (in that area?) and indigenous people have been likely modifying the landscape for somewhere between tens of thousands to thousands of years, stopping only within the last couple of centuries.

I agree with ribuck and neo - If anything, the lack of active land management (low intensity burns) is more of a factor and risk, and NPWS needs to take a more active role if they want to keep the landscape as Europeans' found it. Letting the odd burn loose is probably too infrequent, and leads to the situation we just experienced.
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Re: Wild Wollemi pines, are they really burnt?

Postby north-north-west » Sun 19 Jan, 2020 9:48 am

Ignoring the fact the the safe window for doing appropriate fuel reduction burns is getting smaller due to climate change.
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Re: Wild Wollemi pines, are they really burnt?

Postby LachlanB » Mon 20 Jan, 2020 10:16 am

Siiigh, not the 'we need more cooler burns' furphy again...

In fire conditions with an FFDI (Forest Fire Danger Index) of greater than 50 (this includes a large portion of days the recent fires have spread on), the benefits of fuel reduction (so-called cool burns) decreases to the point where it makes negligible impact, and a fire is almost entirely weather driven. Frequent burning (regardless of severity) often actually increases the fuel load of woodland and forest midstoreys, so the 'active land management' that you advocate Duncan is frequently counterproductive. That is, UNLESS it's happening on approximately a 3 yearly basis, at which point fuel reduction would be sufficient to slow or stop *low intensity* burns. This comes however, at the cost of significant ecological damage, as Australian flora and fauna simply cannot cope with such frequent burning. Also, note the low intensity bit just before: in many areas, even fuel reduction has been found to have either no effect or a negative effect in reducing fire frequency. In severe fire weather, fires just operate too independently and can burn anything, irregardless of fuel loads, topography, drought and vegetation. These severe fires have been a long standing part of the Australian landscape, and there is plenty of evidence of them occurring prior to European settlement of Australia. Our ecosystems can and will recover from them over decades to centuries. What is new is the scale and frequency of the fires. This is due to anthropogenic disturbance/actions and climate change. Getting back to the Wollemi Pines; there's a reason they've been extirpated from the rest of their former range- by the sound of it, the valley they're in is literally too wet to burn most of the time. Except now, in 2019/2020. Because of climate change and accelerated anthropogenic global warming.

And yes, I can provide scientific research to back all of that up.

Also, I didn't include the second half of that quote because I figured it wasn't important for the discussion. Indigenous cultural burning practices is not the issue being argued over on this thread, we've been over it (too) many times on this forum in other threads before. It's a complex issue that can and should be treated separately.
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Re: Wild Wollemi pines, are they really burnt?

Postby potato » Mon 20 Jan, 2020 11:13 am

LachlanB wrote:Frequent burning (regardless of severity) often actually increases the fuel load of woodland and forest midstoreys...

There is so much detail and complexity here... generally this is true but for example, the response of vegetation to fire can be different across varying direction aspects in the same vegetation type.

It is near impossible to summarise bushfire behaviour/ecology in a forum post.
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Re: Wild Wollemi pines, are they really burnt?

Postby LachlanB » Mon 20 Jan, 2020 11:29 am

potato wrote:
LachlanB wrote:Frequent burning (regardless of severity) often actually increases the fuel load of woodland and forest midstoreys...

There is so much detail and complexity here... generally this is true but for example, the response of vegetation to fire can be different across varying direction aspects in the same vegetation type.

It is near impossible to summarise bushfire behaviour/ecology in a forum post.


I generally agree (on both points), but I was moreso talking about high FFDI days (acknowledging that the MacArthur Forest Fire Danger Index can be a flawed tool). On high FFDI days, there is pretty good evidence that weather is the dominant factor that affects fire behaviour, and other variables like vegetation type and aspect decrease in significance as the FFDI rating increase.
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Re: Wild Wollemi pines, are they really burnt?

Postby north-north-west » Mon 20 Jan, 2020 11:54 am

At last, some sense. Thank you, LachlanB.
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Re: Wild Wollemi pines, are they really burnt?

Postby duncanm » Mon 20 Jan, 2020 8:18 pm

LachlanB wrote:Siiigh, not the 'we need more cooler burns' furphy again...

In fire conditions with an FFDI (Forest Fire Danger Index) of greater than 50 (this includes a large portion of days the recent fires have spread on), the benefits of fuel reduction (so-called cool burns) decreases to the point where it makes negligible impact, and a fire is almost entirely weather driven. Frequent burning (regardless of severity) often actually increases the fuel load of woodland and forest midstoreys, so the 'active land management' that you advocate Duncan is frequently counterproductive.
That is, UNLESS it's happening on approximately a 3 yearly basis, at which point fuel reduction would be sufficient to slow or stop *low intensity* burns. This comes however, at the cost of significant ecological damage, as Australian flora and fauna simply cannot cope with such frequent burning. Also, note the low intensity bit just before: in many areas, even fuel reduction has been found to have either no effect or a negative effect in reducing fire frequency. In severe fire weather, fires just operate too independently and can burn anything, irregardless of fuel loads, topography, drought and vegetation.

ok.. I do not know enough about the details to comment. Hence my lack of conviction regarding managed burning.

These severe fires have been a long standing part of the Australian landscape, and there is plenty of evidence of them occurring prior to European settlement of Australia. Our ecosystems can and will recover from them over decades to centuries.

exactly my point

What is new is the scale and frequency of the fires. This is due to anthropogenic disturbance/actions and climate change. Getting back to the Wollemi Pines; there's a reason they've been extirpated from the rest of their former range- by the sound of it, the valley they're in is literally too wet to burn most of the time. Except now, in 2019/2020. Because of climate change and accelerated anthropogenic global warming.

where is the evidence that 2019/20 is worse than history? Most of the Wollemi gorges survived just fine, if we believe the satellite images of vegetation post-fire previously linked in this thread, and the NPWS actions have obviously prevented any particular occurrence of fire in the main grove.


And yes, I can provide scientific research to back all of that up.

Also, I didn't include the second half of that quote because I figured it wasn't important for the discussion. Indigenous cultural burning practices is not the issue being argued over on this thread, we've been over it (too) many times on this forum in other threads before. It's a complex issue that can and should be treated separately.


fair enough.

Still the question remains -- what do we do ?
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Re: Wild Wollemi pines, are they really burnt?

Postby Warin » Mon 20 Jan, 2020 8:44 pm

duncanm wrote:Still the question remains -- what do we do ?


Apparently since the 2009 Royal Commission there have been at least 55 bush fire inquiries. There are 5 common themes from them. Governments are not acting on the recommendations of these inquires they have called. To have yet another one.. why bother when they don't act on them?
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Re: Wild Wollemi pines, are they really burnt?

Postby kymboy » Tue 21 Jan, 2020 6:35 am

Warin wrote:
duncanm wrote:Still the question remains -- what do we do ?


Apparently since the 2009 Royal Commission there have been at least 55 bush fire inquiries. There are 5 common themes from them. Governments are not acting on the recommendations of these inquires they have called. To have yet another one.. why bother when they don't act on them?


According to the ABC there have been 57 inquiries since 1939 not 2009. https://www.abc.net.au/news/2020-01-16/ ... y/11870824

But your question is absolutely right. Why bother with another one when they don't act on them? The answer probably has to do with the prevailing
political wisdom that the more time you can buy between a catastrophic event and the need to be seen to do something meaningful about it, the better chance you have of fudging your responsibilities and avoiding making any tough decisions and so maintain the status quo.
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Re: Wild Wollemi pines, are they really burnt?

Postby duncanm » Tue 21 Jan, 2020 6:50 am

To paraphrase 'yes Minister'

Never start a Royal Commission until you've made sure you know the outcome.

Failure to act on previous repeated recommendations borders on criminal.
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Re: Wild Wollemi pines, are they really burnt?

Postby Warin » Tue 21 Jan, 2020 8:09 am

kymboy wrote:
Warin wrote:Apparently since the 2009 Royal Commission there have been at least 55 bush fire inquiries.


According to the ABC there have been 57 inquiries since 1939 not 2009. https://www.abc.net.au/news/2020-01-16/ ... y/11870824


https://www.abc.net.au/news/2020-01-14/ ... y/11851554

"Over the last 75 years there's been about 140 reviews and inquiries during that time — in a range of areas there are some pretty consistent recommendations," Mr Ellis said.

A 2017 review by the Bushfire and Natural Hazards CRC into 55 major bushfire and disaster inquiries in Australia since 2009 collated 1,336 recommendations.
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Re: Wild Wollemi pines, are they really burnt?

Postby rcaffin » Wed 22 Jan, 2020 6:04 pm

Only thing I'm a bit wary of is they show aerial shots of their location featuring some distinctive topography
You may be very sure that the NPWS vetted those videos very carefully before they were released.
I REALLY doubt that you could identify the site from what is in the videos, taking into account the superb quality of the current Wollemi topo maps ...

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Re: Wild Wollemi pines, are they really burnt?

Postby climberman » Mon 27 Jan, 2020 8:54 pm

duncanm wrote:
LachlanB wrote:https://www.researchgate.net/publication/240738344_Implications_of_a_14_200_year_contiguous_fire_record_for_understanding_human-climate_relationships_at_Goochs_Swamp_New_South_Wales_Australia/link/556cef5e08aec22683054a56/download

It's probably behind a paywall (I don't know because I get institutional access). But the graph on p440 suggests that contemporaneous charcoal levels in Goochs Crater in the Blue Mountain are higher than they have been at any point in the last 14,000+ years. Granted, the charcoal in previous peaks could be from single fires or collections of smaller fires, but it seems pretty obvious that fire activity is currently higher than average.
did the Aboriginal fire practices change the landscape, or was it already well on its way due to the changing climate?



If you search on the same authors as the link by LachlanB (Black, Mooney, Attenbrow), you will come across a paper which essentially says that Aboriginal burning changes lag behind vegetation and climatic changes. Which makes sense.
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Re: Wild Wollemi pines, are they really burnt?

Postby potato » Tue 28 Jan, 2020 6:58 am

From the abstract which I note uses "may" "perhaps" and "parsimonious":

Although the dominant control on fire in this environment during the Holocene appears to be climate, fluctuations in the late Holocene may reflect anthropogenic fire or human responses to climate change. The archaeological record of the Blue Mountains and other parts of the Sydney Basin illustrates that Aboriginal people altered subsistence, resource and land-use patterns in the late Holocene. We propose that these cultural measures were adopted to overcome new risks as the frequency of ENSO events increased, and the natural fire regime and resource reliability changed. These strategies perhaps included a more systematic use of fire. The most parsimonious interpretation of the evidence for changes in fire activity at Goochs Swamp in the light of nearby archaeological evidence is that Aboriginal people used fire within a changing climatic framework.

So essentially the authors acknowledge a lot of doubt in their interpretation of the data. The record presented simply lacks the temporal resolution of local fires to come up with a meaningful conclusion. This is the same with most palaeoclimate records.
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Re: Wild Wollemi pines, are they really burnt?

Postby LachlanB » Tue 28 Jan, 2020 10:03 am

potato wrote:From the abstract which I note uses "may" "perhaps" and "parsimonious":

(paper abstract)

So essentially the authors acknowledge a lot of doubt in their interpretation of the data. The record presented simply lacks the temporal resolution of local fires to come up with a meaningful conclusion. This is the same with most palaeoclimate records.


The real issue (IMO) with most palaeoclimate records is how localised the data is. With many palaeoenvironmental proxies* the conclusions that research makes breaks down very rapidly with distance from a site. For Goochs Crater, the obvious issues are the limited catchment of the crater (certainly less than 5ha), and the sheltered nature of the bowl of the crater. My interpretation of the 'may' and 'appears' is that they simply don't have enough information to conclusively make that call, and are approaching their results with valid scientific caution, as there are a range of potential obfuscating factors with using charcoal evidence. 'Parsimonious' is a rather odd word in this context, I'd think that they're saying 'if you only take a subset of the data, then it can be used to suggest that Aboriginal people used fire within a changing climatic framework'. They unambiguously state in their conclusion that 'A climatic solution can be used to explain all periods of change in the fire history of the landscape surrounding Goochs Swamp'.

I have read another paper recently discussing se-Aus climate and fire over a longer time fame (I think it was about 50k years), but for the life of me I can't find it again... :roll:

Also, if anyone wants to read more than the abstract of that Goochs Crater paper, let me know and I'm happy to send it to you. Abstracts are good and useful, but they are just a summary and are not a substitute for reading the actual paper...


* a proxy is what you are measuring to use to reconstruct past climate or ecology (often the two go hand-in-hand). Common examples are pollen, diatoms, speleothems, tree rings, coral, charcoal, and sediment layers/structure, but there's lots of other proxies out there
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Re: Wild Wollemi pines, are they really burnt?

Postby potato » Tue 28 Jan, 2020 10:18 am

You raise an important point about how localised the data is but its catchment for charcoal and pollen is much larger than 5ha when you consider how far pollen and charcoal can be carried in winds. These records are never perfect - its only once you consider many records from the region do you begin to see a trend.

IMO it is the temporal resolution and the poor understanding of the local processes (wind, erosion, ecology, etc etc) that are the biggest issues with these studies. Again... its only once you consider many records from the region do you begin to see a trend... but as with all of these studies, unless we were there at the time our interpretation of the evidence provided is an educated guess at best.
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Re: Wild Wollemi pines, are they really burnt?

Postby LachlanB » Tue 28 Jan, 2020 11:01 am

potato wrote:You raise an important point about how localised the data is but its catchment for charcoal and pollen is much larger than 5ha when you consider how far pollen and charcoal can be carried in winds. These records are never perfect - its only once you consider many records from the region do you begin to see a trend.


With regards to pollen, it is actually very dependent on the species. Some plant species has very light and mobile pollen that will travel very long distances. Some others would struggles to make 100m.

Likewise with charcoal, the paper is using macroscopic charcoal. This is perfectly normal, but macroscopic and microscopic charcoal target different things. Microcharcoal is a better indicator of regional conditions, as while it is less likely to become airborne than macrocharcoal, once airborne it stays airborne for longer. The reverse is true for macrocharcoal, and hence it is a better indicator of local conditions- one or two things I've read have suggested a range of 1km for air transported macrocharcoal. Macrocharcoal does have the advantage too that it is much, much quicker and easier to assess than microcharcoal... Then there's the also the issue that in-situ fires can produce dramatically more charcoal than remoter fires for a given intensity... So yeah, charcoal is complex and problematic :cry:

potato wrote:IMO it is the temporal resolution and the poor understanding of the local processes (wind, erosion, ecology, etc etc) that are the biggest issues with these studies. Again... its only once you consider many records from the region do you begin to see a trend... but as with all of these studies, unless we were there at the time our interpretation of the evidence provided is an educated guess at best.


I don't think temporal resolution is as big a problem as you're making out. Many proxies can provide extremely detailed information, but obtaining high resolution data is very difficult due to the careful, complex and extensive sampling, documentation, handling, processing, and analysis that is required. This is expensive in time, effort and money, so if researchers can validly and accurately meet their objectives with coarser temporal resolution, they will. Certainly, with regional questions like describing climate change in south-eastern Australia in the Holocene and late Pleistocene that cover tens of thousands of years, a high degree of temporal resolution simply isn't that necessary. I'm also not aware of that much palaeoenvironmental research taking place in the Sydney Basin, there's been some, but not really enough at this point (I think) to make regional assumptions.
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Re: Wild Wollemi pines, are they really burnt?

Postby boronia » Tue 28 Jan, 2020 12:45 pm

rcaffin wrote:Only thing I'm a bit wary of is they show aerial shots of their location featuring some distinctive topography
You may be very sure that the NPWS vetted those videos very carefully before they were released.
I REALLY doubt that you could identify the site from what is in the videos, taking into account the superb quality of the current Wollemi topo maps ...

Cheers
Roger


Once high resolution satellite imagery is available of all burnt areas (Google Earth doesn't seem to have updated yet, can take months for clear images of some areas to be updated), green areas will stuck out like a sore thumb against the charred. Obviously, most/all of the gorges and deep valleys will be green (hopefully) but combined with images released this will probably be the best chance most people have of trying to ID the site/sites. NASA has some nice updated satellite imagery but upon zooming in to various locations it does not seem to retain high resolution. I have been checking it regularly to try and get some idea of whether valleys, gullies and creeks throughout the state really have burned as much as is feared.
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Re: Wild Wollemi pines, are they really burnt?

Postby mandragara » Mon 03 Feb, 2020 11:14 pm

boronia wrote:
Once high resolution satellite imagery is available of all burnt areas (Google Earth doesn't seem to have updated yet, can take months for clear images of some areas to be updated), green areas will stuck out like a sore thumb against the charred. Obviously, most/all of the gorges and deep valleys will be green (hopefully) but combined with images released this will probably be the best chance most people have of trying to ID the site/sites. NASA has some nice updated satellite imagery but upon zooming in to various locations it does not seem to retain high resolution. I have been checking it regularly to try and get some idea of whether valleys, gullies and creeks throughout the state really have burned as much as is feared.


You can already access new satellite imagery using EOS Landviewer: https://eos.com/landviewer/?lat=-32.760 ... Green&anti

Free account needed for higher resolutions.
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Re: Wild Wollemi pines, are they really burnt?

Postby duncanm » Wed 19 Feb, 2020 11:28 am

potato wrote:Fascinating.

I'm a big fan of evidence and the rainfall record suggests this drought is rather unique. The tree ring record might show similar droughts but the detail isn't there to verify the severity of droughts recorded there. In addition, the spatial extent of the fires, to my knowledge of at least the Holocene record, is very unique.


this is worth a read:
https://theconversation.com/500-years-o ... tory-51573

and (I don't have access to the full paper)
https://www.researchgate.net/publicatio ... millennium
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