Adelaide latest victim of global water shortages:
The water in Australia’s biggest river is running so low and is so salty that the nation’s fifth-largest city, Adelaide, is at risk of having to ship water in to its residents, politicians have warned.
Adelaide’s water crisis follows similar problems in cities around the world, as the combination of growing population, increasing agricultural use and global warming stretches resources to the limit. Experts are warning of permanent drought in many regions.
Salinity levels in some stretches of the Murray river already exceed the World Health Organisation’s (WHO) recommendations for safe drinking, and South Australia’s water authority and 11 rural townships east of Adelaide have been told to prepare for the worst.
“Another dry year will deplete our reservoirs and the water in the Murray will become too saline to drink. We are talking about 1.3 million people, who are not far off becoming reliant on bottled water. We are talking a national emergency,” said South Australian MP David Winderlich.
As early as next week, water from parts of the river may become too dangerous to drink, which would require the water authority to begin delivering supplies to hospitals, clinics, aged care facilities and local supermarkets in plastic bottles, said Winderlich.
“There’s simply too many people pulling water out of the river,” said Roger Strother, Coorong council mayor. “We’ve been saying that one day it would catch up, and this summer is when it is going to happen. It could be next week.”
I honestly wonder just how bad things are going to get in Australia over the next decade or so, and beyond that, it’s almost too grim to think about.
If (and that’s still the operative word, albeit barely) Australia will face this level of ongoing drought with very few breaks, I don’t know how they cope. Surely some level of additional conservation can be instituted beyond their current measure, but I suspect many parts of Australia have already picked all the low- and medium-hanging fruit, leaving room for little additional savings. At what point do people start giving up and leaving?
I’m sure that desalination will likely become more widely used, although the energy requirements and monetary costs are high, plus there are limits to the amount of brine (concentrated sea water) that can be returned to the ocean from each coastal site.
Two Meter Sea Level Rise Now Inevitable – But How Fast Will It Happen?:
Geez, this week is filled with dire climate change news: Reuters reports that sea level rise expert Stefam Rahmstorf of the Potsdam Institute says that two meters of sea level rise is inevitable at this point. The main variable now is how quickly that will happen:
There is no way I can see to stop this rise, even if we have gone to zero emissions.
There is nothing we can do to stop this unless we manage to cool the planet. That would require extracting the carbon dioxide from the atmosphere. There is no way of doing this on the sufficient scale known today.
The best possible outcome right now, Rahmstorf said, is that we stabilize temperatures and that sea level rise happened at a steady rate over the next few centuries, and not accelerate.
This calls into question one of the immense assumptions we’re all carrying around, namely the guideline that claims the magic number for temperature rise is 2°C over the preindustrial level. I’ve written about this before (see Two degrees of separation), and I’m more convinced than ever that 2°C is not the right number, simply because it was chosen as “the” goal roughly 20 years ago, and we’ve learned a lot about how the Earth’s climate responds to a sustained blast of greenhouse gas emissions since then, and all the evidence points in the wrong direction. Just the revelations about ice sheet dynamics, specifically how much quicker we now know for a fact that they can melt and break up, should make us admit to ourselves that we’re in for a world of pain at “only” 1.8 or 1.5 °C. Given that we’ve already seen a rise of 0.8°C and we have something like another 0.6°C “in the pipeline”, we’re perilously close to being over the limit today.
Post-human Earth: How the planet will recover from us:
When Nobel prize-winning atmospheric chemist Paul Crutzen coined the word Anthropocene around 10 years ago, he gave birth to a powerful idea: that human activity is now affecting the Earth so profoundly that we are entering a new geological epoch.
The Anthropocene has yet to be accepted as a geological time period, but if it is, it may turn out to be the shortest – and the last. It is not hard to imagine the epoch ending just a few hundred years after it started, in an orgy of global warming and overconsumption.
But first we’ll go through what I’ve termed the Metricene, the time when not only are we altering the environment, but we’re aware of the consequences and we’re forced to attempt to directly manage the climate.
Whether our species would survive is hard to predict, but what of the fate of the Earth itself? It is often said that when we talk about “saving the planet” we are really talking about saving ourselves: the planet will be just fine without us. But would it? Or would an end-Anthropocene cataclysm damage it so badly that it becomes a sterile wasteland?
The only way to know is to look back into our planet’s past. Neither abrupt global warming nor mass extinction are unique to the present day. The Earth has been here before. So what can we expect this time?
Take greenhouse warming. Climatologists’ biggest worry is the possibility that global warming could push the Earth past two tipping points that would make things dramatically worse. The first would be the thawing of carbon-rich peat locked in permafrost. As the Arctic warms, the peat could decompose and release trillions of tonnes of carbon into the atmosphere – perhaps exceeding the 3 trillion tonnes that humans could conceivably emit from fossil fuels. The second is the release of methane stored as hydrate in cold, deep ocean sediments. As the oceans warm and the methane – itself a potent greenhouse gas – enters the atmosphere, it contributes to still more warming and thus accelerates the breakdown of hydrates in a vicious circle.
“If we were to blow all the fossil fuels into the atmosphere, temperatures would go up to the point where both of these reservoirs of carbon would be released,” says oceanographer David Archer of the University of Chicago. No one knows how catastrophic the resulting warming might be.
That’s why climatologists are looking with increasing interest at a time 55 million years ago called the Palaeocene-Eocene thermal maximum, when temperatures rose by up to 9 °C in a few thousand years – roughly equivalent to the direst forecasts for present-day warming. “It’s the most recent time when there was a really rapid warming,” says Peter Wilf, a palaeobotanist at Pennsylvania State University in University Park. “And because it was fairly recent, there are a lot of rocks still around that record the event.”
By measuring ocean sediments deposited during the thermal maximum, geochemist James Zachos of the University of California, Santa Cruz, has found that the warming coincided with a huge spike in atmospheric CO2. Between 5 and 9 trillion tonnes of carbon entered the atmosphere in no more than 20,000 years (Nature, vol 432, p 495). Where could such a huge amount have come from?
Volcanic activity cannot account for the carbon spike, Zachos says. Instead, he blames peat decomposition, which would have happened not from melting permafrost – it was too warm for permafrost – but through climatic drying. The fossil record of plants from this time testifies to just such a drying episode.
If Zachos and colleagues are right, then 55 million years ago Earth passed through a carbon crisis very much like the one feared today: a sudden spike in CO2, followed by a runaway release of yet more greenhouse gases. What happened next may give us a glimpse of what to expect if our current crisis hits full force.
See the article for more on how a potential replay of the Paleocene-Eocene thermal maximum event might impact a post-human world. Cheery stuff, he typed with the driest possible sarcasm.
