Category Archives: Victoria floods

To attribute, or not to attribute: that is no longer the question

Things that scare me: redux

How many of readers recall early 2011 when cyclone Yasi struck Brisbane?

At least 35 people died in floods across New South Wales and Queensland. The resulting rains and floods costed the Australian economy approximately $10 billion.

Or the flooding suburbs in Melbourne, which I captured on video. So extreme were these events that it caused one member of the Bureau of Meteorology to exclaim: “We’ve never seen anything like it in Australia”

Perhaps you may recall early 2011 fires raged in Western Australia (Black Sunday), while Sydney experienced a record seven-day heat wave.

Across the globe soaring temperatures saw record rains flood two-thirds of Pakistan, while at the same time fires raged across Russia.

Or perhaps your memory goes back to the 2010 records floods in China killed close to 400 people, destroying 1.3 millions homes and caused $54USD billion in damage?

Perhaps some might remember the fires that ripped through Israel in an event called that nations worst natural disaster in history?

Of course there where the floods in Niger and the record rain in the US that saw Nashville inundated.

Indeed in September 2010 I wrote about the things that scared me about the coming Australian summer:

Thus with 2010 looking like being the hottest year record, I think we should be deeply concerned about the coming bushfire season.

As noted by the IPCC, with rising temperatures Australia could be subjected to more floods and catastrophic fires…I earnestly hope some advanced planning is taking place.

While let me reiterate my concerns for the coming Australian summer of 2012-13.

I’m not claiming any prescience, just noting the obvious fact an increase in CO2 that traps more heat, raises temperatures and fuels more extreme weather events.

It makes sense because the science is pretty fucking solid.

The attribution debate is over

Back in 2010 and early 2011 “sensible” voices cautioned about attributing these events to climate change.  This is the so called “attribution” question, and we’re cautioned to not make simple linkages between a flood here and climate change: fair enough.

I recall Michael Tobis writing for the now defunct “Only in it for the gold” asking that very question in 2010 reflecting on the Russian heat wave:

But right now I feel like hazarding a guess. As far as I understand, nothing like this has happened before in Moscow….

…The formerly remarkable heat wave of 2001, then, is “the sort of thing we’ll see more of” with global warming. But it may turn out reasonable, in the end, to say “the Russian heat wave of 2010 is the first disaster unequivocally attributable to anthropogenic climate change.”

Tentative, hedging and qualifying like a good scientist and commentator on this issue should.

Still the blogger Eli at Rabett Run said Michael was asking a “scary question”, noting sardonically:

As Dirty Harry would say, at some point the bunnies have to ask not if the dice are loaded, but if the 44 Magnum is.

Picture the clathrate gun hypothesis playing the role in Eli’s similes of bunnies playing with 44 Magnums. Go on click that link –but only if you’re prepared for the possibilities of loosing sleep.

On second thoughts, you will lose sleep.

So let me state this: it is now pointless wrangling over the question of whether or not to attribute individual events to climate change.

Reality makes that debate redundant.

We’re here: we’ve arrived at the point in history when our species has engineered a new climate. The point we knew was coming – that was inevitable – if we did nothing.  

Slouching towards the Anthropocene

Let’s recap the past few months shall we?

The North American heat wave with 40,000 temperature records broken; six million displaced in India due to monsoon rains, 150 dead in Russia as several months worth of rain falls in a matter of hours; Arctic and Greenland ice loss…

Need I go on?

It’s unfolding as if climate change was real… funny that huh?

I was going to muse on what this all means, but I’ve already did that in August 2010 in the post “Welcome to the Anthropocene”:

Being a blogger frees me from the usual reticence and qualified statements scientists usually (for good reason) make.

I may appear very foolish for saying this, but its time to call it: we’ve well and truly passed a threshold.

Call it climate change, or global warming. Or perhaps you could rename the planet as Bill McKibben suggests (Eaarth). Actually the name really doesn’t matter.

This is the new normal.

Even if we stopped all CO2 emissions tomorrow, there’s more than enough warming “in the pipe” for future “climate disruption”.

The Greenland ice sheet?

Most likely gone.

The Great Barrier Reef.

Most likely gone.

2010 is the year in which the climate news is getting worse: hottest year on record; the ocean’s phytoplankton dying off; the Russian heat wave; the floods in Pakistan (2).

Welcome to the anthropocene.

That’s the thing about the climate change debate. You end up saying the same thing over, and over again. Though who listens is another question…

Famously, one scientist called the climate an angry beast, and that our activities are provoking it. Permit me to run with that metaphor and repurpose the final lines of “The Second Coming” by W.B. Yeats:

And what rough beast, its hour come round at last,
Slouches towards the Bethlehem to be born?

And what a beast climate change is: slowly, almost methodically it slouches into perception and our lives.

There will come a time when all of us will be forced to stare into face of the beast, aghast and transfixed, like Saturn’s sons staring into the gaping maw of their father.

Ross River virus hits Victoria: increased risk for southern Australia*

"Say hello to my little friend..."

 

 

The combined effects of heat and extreme flooding have seen the mosquito population explode in Victoria. So much so that a surge in cases of Ross River virus (RRv) is hitting those flood affected parts of Victoria:

 

VICTORIANS are being warned to brace themselves for outbreaks of diseases such as Ross River fever and Barmah Forest virus as mosquito populations explode across the state.

Health Minister David Davis said Victoria’s higher rainfall meant there would be more risk from mosquitoes this summer.

”The department is very aware of these risks and is in close communications with local authorities,” he said.

There has been a significant rise in the number of reported cases of Ross River fever and Barmah Forest virus as unseasonably wet and warm conditions in the first two weeks of January provided perfect breeding conditions for mosquitoes.

In the first 12 days of January there were 23 cases of Ross River virus confirmed by blood test in Victoria, and a further 21 cases of Barmah Forest virus – more than four times the number of reported cases for the same period last year, when there were six cases of Ross River fever and four cases of Barmah Forest virus.

In 2008, there were just four reported cases of both viruses in the first 12 days of January.

”I think the data speaks for itself,” said Health Department spokesman Graeme Walker.

”We were prepared for this, and issued a health warning just before Christmas.”

The “peak” period for infections is due over the next few weeks, as mosquitoe larvae mature and hatch.

What is happening in Victoria is also true for South Australia:

 

Rising flows in the Murray have led to a surge in mosquito-borne infections in South Australia.

Cases of Ross River virus and Barmah Forest virus are now beyond 350, compared with little more than a dozen cases at the same time a year ago in the Riverland.

Dr Grant Baker, from the Riverland Division of General Practice, said it was a cause for great concern.

“They need water and obviously up here in the Riverland we’ve gots lots of water at the moment,” he said.

He said mosquitoes did not travel far, but the virus could be carried further by birds and animals such as marsupials.

Dr Baker said Ross River symptoms included fever, rashes and aching joints.

What is the Ross River virus?

The New South Wales government provides an overview of the disease here:

 

What is the Ross River fever?

  • Ross River virus is one of a group of viruses called arboviruses (or arthropod-borne viruses), which are spread mainly by blood-sucking insects.
  • Ross River virus is a germ that infects people, particularly in rural areas, sometimes causing a flu-like illness with joint pains, rash and fever.
  • Ross River virus is not fatal.

What are the symptoms?

  • Many people who are infected with the virus will never develop symptoms.
  • Some people will have flu-like symptoms that include fever, chills, headache and aches and pains in the muscles and joints.
  • Some joints can become swollen, and joint stiffness may be particularly noticeable in the morning.
  • Sometimes a rash occurs on the body, arms or legs. The rash usually disappears after seven to 10 days.
  • A general feeling of being unwell, tired or weak may also occur at times during the illness. This may affect work performance.

See also the Victorian Department of Health for further information.

Even though it is not a fatal disease, by all accounts it sounds very uncomfortable. There is no real “cure”: those contracting RRV have to “ride it out”.

RRv in Australia: past and present

Each year there are about 5000 cases reported, with outbreaks more generally associated with the tropics – but cases are reported all over Australia.

As the above map makes clear, incidences occur frequently up North. RRv was first documented in 1928, but the virus itself was only isolated in 1959:

 

The first documented outbreak of RRV occurred in 1928 in Narranderra and Hay in New South Wales with subsequent outbreaks described during World War II among troops in the Northern Territory and Queensland. The virus was isolated in 1959 from an Aedes vigilax mosquito along the Ross River near Townsville in Queensland, although it was not until 1985 that it was isolated from an Australian patient with polyarthritis. Outbreaks have since occurred in all Australian states, including Tasmania, and have occurred in metropolitan areas of Sydney (New South Wales), Perth (Western Australia) and Brisbane (Queensland). Most notifications are from Queensland, with high case rates also reported from Northern Territory and the Kimberley region in Western Australia.

However, as the climate changes, RRv may be on the move.

The connection between RRv and climate change

The rate of transmission of RRv is dependent on a number of factors, as this 2008 paper makes clear. However climate change is having an impact. As the authors note, increased humidity create the perfect conditions for increased populations of mosquitoes:

 

Relative humidity influences longevity, mating, dispersal, feeding behaviour, and oviposition of mosquitoes. At high humidity, mosquitoes generally survive for longer and disperse further; they have a greater chance of feeding on an infecting animal and surviving to transmit a virus to humans or other animals. Relative humidity also directly affects evaporation rates from vector breeding sites. Clearly, humidity is another factor contributing to outbreaks of RRv disease, particularly in normally arid regions.

And that climate change is playing a part:

As global warming continues, it is important to assess the potential public health consequences of such change, including its impact on the transmission of infectious diseases. The results of this study indicate that climate variability/change may influence the transmission cycles of RRv, and its impact appears to differ between coastline and inland regions. These findings may have implications in the development of public policy for mitigation and adoption of climate change.

An early warning sign of a changing climate

One of the anticipated impacts of climate change is the steady march south (and north) of tropical diseases. Indeed, their movement is regarded as an “early warning” sign. The Union of Concerned Scientists have noted:

Climate change affects the occurrence and spread of disease by impacting the population size and range of hosts and pathogens, the length of the transmission season, and the timing and intensity of outbreaks (McMichael, 1996; McMichael et al., 1996; Epstein et al., 1998; Epstein, 1999). In general, warmer temperatures and greater moisture will favor extensions of the geographical range and season for vector organisms such as insects, rodents, and snails. This in turn leads to an expansion of the zone of potential transmission for many vector-borne diseases, among them malaria, dengue fever, yellow fever, and some forms of viral encephalitis. Extreme weather events such as heavy rainfall or droughts often trigger disease outbreaks, especially in poorer regions where treatment and prevention measures may be inadequate.

Mosquitoes in particular are highly sensitive to temperature. The mosquitoes that can carry malaria (Anopheline spp.) generally do not develop or breed below about 16° C, and the variety that transmits dengue fever (Aedes aegypti) is limited by winter temperatures below 10° C. Mosquito survival also drops at their upper temperature threshold, about 40° C. With sufficient moisture, warmer temperatures will generally cause an increase in mosquito abundance, biting rates, and activity level, and will accelerate the incubation of the parasites and viruses within them.

Warmer global temperatures will allow an expansion of the geographic range within which both the mosquito and parasite could survive with sufficient abundance for sustained transmission. Model predictions indicate that a 3° C global temperature rise by 2100 could increase the number of annual malaria cases by 50-80 million (not considering factors such as local control measures or health services) (Martens et al., 1995). The largest changes will occur in areas adjacent to current risk areas, at both higher altitudes and latitudes. In these regions, a temperature increase can convert areas that are malaria-free into areas that experience seasonal epidemics. In many cases, the affected populations will have little or no immunity, so that epidemics could be characterized by high levels of sickness and death.

This is inline with model projections:

 

Recent disease outbreaks are consistent with model projections that warmer, wetter conditions will lead to greater transmission potential at higher altitudes and elevations. Mosquito-borne diseases are now reported at higher elevations than in the past at sites in Asia, Central Africa, and Latin America (Epstein et al., 1998).

Already, climate change has (most probably) brought malaria and other diseases back to Italy:

 

Sandwiched between temperate Europe and African heat, Italy is on the front line of climate change and is witnessing a rise in tropical diseases such as malaria and tick-borne encephalitis, a new report says.

Italy was declared free of malaria in 1970, but it is making a comeback, said the Italian environmental organisation Legambiente. Tick-borne encephalitis, a virus which attacks the nerve system, is also on the way back. While only 18 cases had been reported before 1993, 100 have been since, mostly around Venice.

“Illnesses are arriving from Africa, while tropical animals and plants are attacking our biodiversity, droughts and flooding are on the rise, and semi-desert areas are appearing,” said Legambiente’s director general, Francesco Ferrante.

A third ailment, visceral leishmaniasis, carried by sandflies and potentially fatal, is expanding rapidly, the report added. Cases in Italy have risen to 150 a year from 50 before 2000, with the southern region of Campania a hotspot.

Of six sustained droughts in Italy in the last 60 years four have occurred since 1990. The average temperature has increased by 0.4C in the north in 20 years and by 0.7C in the south. Ten million hectares “are at risk of desertification”.

Twenty percent of the fish now swimming in the Mediterranean, including barracuda, are types that have migrated from the Red Sea as water temperatures rise.

Italy’s combination of sea coast, mountains, deep valleys and plains gives rise to a rich variety of food products but climate change could tip the balance, Mr Ferrante said. “We are at the southern edge of the globe’s temperate area and that is why Italy is being particularly hit by the collapse of the climatic equilibrium.”

But of course, this is all a co-incidence.

* Title edited for clarity, hat tip to reader John Byatt

The Long Reach of Yasi Part 2: BoM “We’ve never seen anything like this in Australia”; more towns evacuated as residents forced to flee

Hard to believe, but such was the force of Cyclone Yasi that is playing havoc with Victoria’s weather. The Bureau of Meteorology calls it “unprecedented“:

Across the state, about 4500 homes were still without power last night. Mr Baillieu urged those in need of help to wait patiently. ”This is a difficult rain event. It’s been widespread across Victoria and the SES are doing the best they can to support those with requests for assistance,” he said.

Bureau of Meteorology forecaster Terry Ryan said the ”unprecedented” movement of cyclone Yasi inland to the Northern Territory, combined with a longer cloud band caused by ex-cyclone Anthony, had produced a humid and unstable air mass over Victoria. ”We’ve never seen anything like it in Australia,” he said.

The impact of the storms have been quite severe:

State Emergency Service crews were stretched to the limit with almost 6000 calls for help, including 4100 in Melbourne, by yesterday afternoon.

A 26-year-old British tourist remained in a critical condition with serious head injuries, after a gum tree fell on her tent at the Crystal Brook Tourist Park in Doncaster East, just after midnight yesterday. Almost 100 people were rescued across the state, including 60 people from vehicles trapped in flash flooding. Three teenage boys were forced to cling to a telegraph pole in a swollen creek while waiting for rescuers at Pakenham.

The Alfred hospital was forced to relocate patients and close several operating theatres because of flooding. More than 40 elderly residents had to be evacuated from nursing homes at Mentone, Narre Warren and Werribee.

Flash flooding in Melbourne’s west and south-east closed the Monash Freeway and Princes Highway, causing traffic jams up to 10 kilometres long. Several train lines were closed.

The cause:

VICTORIA has been lashed by the tail of cyclone Yasi, producing severe storms and torrential rain.

The moist air from Yasi, downgraded from a cyclone to a tropical low after its winds eased below gale force, was dragged south in an arc from Queensland’s north-west, through Alice Springs and as far south as Melbourne.

A large cold front heading north cooled the warm monsoonal air and caused huge cloudbursts that dumped up to 200 millimetres of rain in just two hours over Melbourne and regional Victoria.

Moisture remaining from cyclone Anthony was also hanging over the state and contributed to the deluge.

Bureau of Meteorology senior forecaster Stephen King said the weather was unusual for Melbourne.

My video captured some of it’s force, my own local area was hit hard.

Carlisle Street, my local area turned “into a river” according to shop owners I talked to yesterday.

Owners of the Balaclava Fresh Centre, people I’ve been shopping with for over ten years, spent a sleepless night protecting their stock from flood waters. Both the local Coles and Safeway were forced to close due to rain damage to their buildings.

The places I grew up…

I’m a “Dandy Boy”, I spent most of my first 25 years of my life in Dandenong.

And now the suburb I grew up in has experienced flooding:

Source: Herald Sun

According to the BoM:

The Dandenong Creek catchment has received rainfall averaging about 147mm since 09:00am yesterday.

The water level of the Dandenong Creek at Rowville (Police Road retarding basin) has exceeded the Moderate flood level of 5m. Given no further rainfall, water level at the basin is likely to peak close to the major flood level of 5.5m this evening.

Roads and low lying areas adjacent to the waterway are still affected by flooding. Please check VicRoads website for roads affected by flooding.

Dandenong Creek is a tiny string of water that trickles it way through the area. Calling it a “creek” was local “in joke”, given it was on the most unattractive and degraded water ways I’ve seen. The “Mighty Dandenong” could barely live up to it’s name as a creek.

And now it has roared to life, flooding the area.

More towns evacuated

If it wasn’t bad enough, more towns are being evacuated across the state. The Herald Sun reports:

THOUSANDS of people were given two hours to get out of their homes as fast-rising floodwaters last night threatened to engulf four country towns.

The State Emergency Service said it had told more than 6000 residents of Koo-wee-rup, Iona, Bayles and Cora Lynn in Gippsland to grab their pets, medicine, photographs and three days’ clothes and flee to emergency centres in Cranbourne and Pakenham.

The warning came as the Lower Bunyip River swelled dangerously upriver, and was tipped to peak at more than 7.2m in the early hours of today.

A ferocious dump of rain caused by Queensland’s tropical cyclones Yasi and Anthony swept across Victoria, flooding dozens of homes from Melbourne to Mildura, closing hundreds of roads, inundating schools and churches and leaving a damage bill approaching an estimated $100 million.

I’ve lived in Melbourne all my life, and I’ve seen fire and rain.

I remember Ash Wednesday, Black Saturday and the floods, droughts and extreme weather events. We’ve always had them – Australians understand just how harsh our climate can be.

But this?

This is different.

Everywhere I go people are talking:

“Is this climate change?”

These floods aren’t abstract to me.

The places I grew up, visited and now live in are witnessing unprecedented rains and flooding.

Further resources

Images sourced: The Age; Herald Sun

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