Dry winter primes Sydney Basin for early start of bushfire season


Matthias Boer, Western Sydney University; Rachael Helene Nolan, University of Technology Sydney, and Ross Bradstock, University of Wollongong

It might feel like the depths of winter, but Australian fire services are preparing for an early start to the bushfire season. Sydney has been covered with smoke from hazard reduction burns, and the New South Wales Rural Fire Service has forecast a “horrific” season.

Predicting the severity of a bushfire season isn’t easy, and – much like the near-annual announcements of the “worst flu season on record” – repeated warnings can diminish their urgency.

However, new modelling that combines Bureau of Meteorology data with NASA satellite imaging has found that record-setting July warmth and low rainfall have created conditions very similar to 2013, when highly destructive bushfires burned across NSW and Victoria.

Crucially, this research has found we’re approaching a crucial dryness threshold, past which fires are historically far more dangerous.


Read more: Climate change to blame for Australia’s July heat


How to measure bushfire fuel

On September 10, 2013 several bushfires in Sydney’s West caused havoc well before the official start of the bushfire season. These were a precursor to fires that destroyed more than 200 properties a month later. Warm, dry winter weather had dried out the fuels in Sydney’s forests and bush reserves beyond “normal” levels for the time of year.

The timing and severity of those preseason fires were a reminder that the region’s forests are flammable all year round; they can burn whenever the fuel they contain dries out past a certain threshold.

In most forests, there is an abundance of fuel in the form of leaf litter, dead twigs, branches and logs, lower vegetation such as shrubs and grasses, as well as higher foliage and branches.

The flammability of all these different kinds of fuel depends largely on their moisture content. Leaf litter and fine dead branches on the soil surface can dry out in a matter of days, whereas logs may take weeks or months to lose their moisture. The moisture content of shrubs and tree canopies varies depending on the amount of water in the soil, so they reflect the overall rainfall and temperatures across a whole season.

The flammability of an entire forest is therefore a complex calculation of all these different kinds of fuel (both alive and dead) and their different moisture levels.

Mapping Sydney’s forests

In a recent collaborative study, we combined data from a Bureau of Meteorology project that maps water availability levels across Australia with satellite imagery to develop new tools for mapping and monitoring moisture levels of different fuels in forests and woodlands.

We checked these tools by modelling fuel moisture levels during fires in NSW, Victoria and the ACT between 2000 and 2014, and comparing our predictions to historical bushfires.

Our research has identified critical dryness thresholds associated with significant increases in fire area. Rather than a gradual increase in flammability as forests dry out, when dead fuel moisture drops below 15% subsequent bushfires are larger. Another jump occurs when dead fuel moisture levels fall below 10%. We found similar thresholds in growing plants, although their moisture content is measured differently.

These dryness thresholds are pivotal, because they may represent the breakdown of moist natural barriers in landscapes that prevent fires from spreading. Understanding these mechanisms makes it possible to predict fire risk much more accurately.

As part of this project we compared the fuel moisture in Sydney Basin’s forested areas in 2013 and 2017. As shown in the chart below, currently the live fuel moisture level is tracking well below the 2013 values, and is approaching a crucial threshold (indicated by the dotted line).

The moisture content of dead fuel has been more variable, but it has also dipped below the 2013 curve and, if warm dry weather continues, could reach critical levels before the end of August.


The median predicted dead fuel moisture content and live fuel moisture content in forest areas of the Sydney Basin Bioregion in 2013 and 2017. Black dashed horizontal lines indicate fuel moisture threshold values. The start dates of major fires in 2013 are indicated by orange vertical lines.
Author provided, Author provided

In another worrying sign, mapping shows critically dry live fuel is much more abundant in 2017 than it was in 2013.


Remotely sensed live fuel moisture content in forest areas of the Sydney Basin Bioregion in July 2013 (left) and July 2017 (right). Click to enlarge.
Author provided

It’s clear that much of the Sydney Basin is dangerously primed for major bushfires, at least until it receives major rainfall. Forecasts for windy but largely dry weather in coming weeks may exacerbate this problem.

These new insights into landscape-scale fuel dryness provide a powerful indicator of what might be expected. They also build our capacity for week by week monitoring of fire potential.

The ConversationPreparation by both fire management authorities and exposed homeowners is now an immediate priority, to cope with the strong likelihood of an early and severe fire season.

Matthias Boer, Associate Professor, Hawkesbury Institute for the Environment, Western Sydney University; Rachael Helene Nolan, Postdoctoral research fellow, University of Technology Sydney, and Ross Bradstock, Professor, Centre for Environmental Risk Management of Bushfires, University of Wollongong

This article was originally published on The Conversation. Read the original article.

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A Problem with Expository Preaching?


I have recently come across an article on the Banner of Truth website that ‘deals’ with expository preaching, or rather, attempts to define the dangers of what goes by ‘expository preaching’ in this day and age. The basic explanation or definition given in the article is pretty good really – that of a preacher confining himself to the text of Scripture and making it plain to others. That in itself is a fairly good explanation of being ‘expository’ I think. I do however think that some other things are probably required to fulfill the definition of what preaching ought to be – such as there being a place for application to the listeners, etc.

My point of disagreement with the article in question, is that of the need to issue a ‘caution’ to what goes by expository preaching today, which according to the article is the method of preaching through a passage or a book of Scripture week by week. I have no issue with saying that this is not the only way of being expository, but to issue a caution about the ‘modern way’ seems somewhat extreme to me.

I wouldn’t say that the ‘modern way’ is the only way to preach, nor would I go so far as to say it is the best way of preaching. I would say that I find it the best way of preaching for me, but I wouldn’t lay it down as a rule for others. I think the method of preaching used by a preacher is best left to that preacher and between himself and the Lord. I don’t think I would even call most of the preaching of Charles Haddon Spurgeon expository, yet you cannot argue that he didn’t preach in a manner used of God. So I think caution needs to be used in laying down ‘rules’ as to what method of preaching is best for a preacher, etc.

I have heard ‘preaching’ that has been systematic in its approach to a book of the Bible and it has left me bored, dry and thinking ‘what was the point of listening to it.’ However, as a person commented on the Banner of Truth article, this has probably got more to do with the validity of the preacher’s call than anything else. Perhaps the preacher is in a not so good place before God at the time of preaching also. Who knows – but a bad experience of someone ‘preaching’ systematically through a book of the Bible or passage doesn’t necessarily mean that that method is therefore proven to be a bad one. There are other variables that come into the picture.

So the Banner of Truth article is probably leading off in the wrong direction in my opinion. Readers of this Blog can make up their own opinion by reading the said article at:

http://www.banneroftruth.org/pages/articles/article_detail.php?1777

POST-MODERNISM AND TRUE CHRISTIANITY


It is my contention that the church has been invaded and conquered by Post-modernism. When I say the church, I mean that which goes my the name today, in general terms. I am not of course speaking of the true church in the Biblical sense.

How else can we explain the eclectic and ever varying viewpoints and paradigms of churches throughout the country (Australia) and the world, except that the church has been invaded and conquered by Post-modernism? It is rampant everywhere and it no longer needs a subtle approach to infiltrate the church. It can now appear in blinding light as Post-modernism and be found acceptable by most ‘Christians’ within this country and I suspect the world.

Opposition to Post-modernist ideas is difficult to find, though admittedly it is there. The particularbaptist.com website is one outpost of Biblical Evangelical Christianity (Particular Baptist). It is not the only one – there are many such outposts on the World Wide Web and throughout the spiritual wilderness one can find an occasional welcome oasis in a dry, barren desert.

Yet the overwhelming scenario is that entering a random ‘Christian’ church on any Sunday you will find a place devoid of the Spirit of God, for He has long ago withdrawn His candlestick from that place. It is quite likely that you will find a place that for some time has given itself over to fanciful stories, human devised fables and crowd-pleasing activities. The people there have welcomed leaders that have been only too pleased to scratch the ears of their followers and have eagerly lapped up fleshly pleasing rhetoric that has fallen from their poisoned lips.

What are we to do who find ourselves hungering and thirsting in the wilderness? Are we to join ourselves to one of these dens of iniquity because we are not to forsake the assembling of ourselves together? Is this the last desperate act left open for a believer who longs to be obedient to His Lord?

I think it is high time that we who truly believe the Bible and follow the God of the Bible and His Beloved Son and the leadings of His Spirit, separate ourselves from such synagogues of Satan and form true Christian churches after the form outlined in the New Testament. It is time that we leave these forsaken places to their own devices and set out on a pathway that has been marked out by those that have gone before.

Our congregations may only be small and seem to have little impact when contrasted with the Post-modernist mega-churches of our time, yet we will be faithful servants of our God. We will be able to trust Him who is our Refuge and Our Strength, knowing that He who will go before us is the all-conquering sovereign Lord.

I find myself in this barren spiritual desert, surrounded by Post-modernist churches and have often felt the need to meet with Christians as I know I should. Yet I find myself unable to meet with those that worship another God and peddle another gospel that I find abhorrent. I long for the day when I will be able to meet with even two or three like-minded godly brethren who will also not yield to the pressures of the day and simply meet with a ‘powerless’ church that has long lost the powerful Spirit of God and is no longer a true witness of Jesus Christ.

May the Lord raise up like-minded brethren who will come together and form the godly churches of tomorrow. May God yet come among us again through the Person and Work of the Holy Spirit and visit us with fresh displays of His gracious power in the Gospel of Jesus Christ.

AUSTRALIA: FLOODING CRISIS IN QUEENSLAND TO GET WORSE AS CYCLONE CLOSES ON COAST


As Queensland begins to dry out after flooding affected 60% of the state, the flooding crisis is set to get worse as Cyclone Hamish closes on the Queensland coast near Townsville. The cyclone intensified overnight to a category 3 system and is expected to reach category 4 before it crosses the coast somewhere in the vicinity of Townsville.

Heavy rains and winds are already buffeting the coast, with some areas having already received in excess of 160 mm of rain. The cyclone is generating 220 km per hour winds and is located about 220 km of the Queensland coast to the east of Cairns.

The cyclone is expected to cross the coast in about 36-48 hours time.

BUSHFIRES FINALLY ARRIVE AS HEAT WAVE CONTINUES


The bushfire season has taken a bit longer than usual to arrive this year, but in the last couple of days bushfires have begun to appear across Australia and in particular in New South Wales and South Australia.

In my region the temperatures rose to the mid thirties (Celsius), while further to the west the temperatures reached the low forties – which has been the case for several days now.

A cooler change is expected in the very near future but temperatures will remain in the mid to high thirties tomorrow before another cool change. The high temperatures will then return at the beginning of next week.

In short, the bushfire season in eastern Australia is now well and truly here and more fires can be expected over the next couple of months – especially given how dry it currently is.

There have been fires around Sydney over the last couple of days with some property (sheds, vehicles, etc) being destroyed by fire today. There have been other fires around, including near Gloucester and Singleton. In South Australia there was a particularly bad fire at Lincoln.

BELOW: Footage of the bushfires