Friday, March 02, 2012

Warragamba is spilling: first time in 14 years

Warragamba Dam, Sydney's main water catchment and storage facility, is now at 100% capacity and started spilling about an hour or two ago. This is likely to contribute to rising floodwaters downstream along the Hawkesbury-Nepean Rivers, which are rising rapidly due to heavy rain. Something like 900 houses are on evacuation alert.

However, in the headlines about localised flooding, let us not lose the wood for the trees. While a full dam is undoubtedly excellent news for the immediate prospects of Sydney's water supply, it is worth remembering that just five years ago, the dam was below 35% and it has not been full since 1998. The situation was threatening enough in 2007 to lead the NSW State government to build a major desalination plant as a precautionary back-up.

Australia has long been known as a land "of droughts and flooding rains". The intensity of our hydrological cycle, regularly bringing both extremes, is one of the challenges faced by our ecosystems (including the human social system). Our familiarity with the dangers of this intensity can numb us to the warnings of climate scientists, that our continued pollution of the atmosphere is likely to bring even more intensity to the hydrological cycle. Simply saying that we've had floods and droughts before does not excuse us from paying attention to the increasing threat these now represent. When combined with rising human population (and rising consumption levels) in a land of fragile soils and ecosystems already significantly modified and degraded by human impact, the implications of these climate projections should not be ignored.

The last 24 months have been the wettest in Australia's recorded history, and they have followed one of our most severe droughts. As always, these have been associated with the El Niño-Southern Oscillation (ENSO) cycle, however, this natural cycle now has a strong warming trend superimposed on it, bringing more moisture into the atmosphere and redistributing it differently in space and time to familiar patterns from the past. We Australians are not immune from the changes our actions are helping to cause.

And if we are tempted to minimise our contribution to this global problem, keep in mind three factors:

(a) Australian per capita emissions are higher than all other countries except some micro-nations and petro-states with heavily subsidised oil prices. Our historical emissions put us in the top ten emitters worldwide (not per capita). These figures exclude both coal exports and our propensity to take frequent overseas flights.

(b) We are the world's largest exporter of coal and have plans to continue greatly expanding our coal production on a scale that will, by 2050, use up more than 10% of the global carbon budget required to have a decent change of keeping us below 2ºC warming. Indeed, expansion of coal exports will lead to carbon dioxide emissions 11 times greater than the projected savings of the recently passed carbon pricing legislation.

(c) As a nation with one of the highest standards of living in the world (being regularly placed in the top ten for quality of life in various surveys), we can afford serious action more easily than almost any other nation, having almost greater freedom from other pressing concerns than anywhere else.

So let us thank God for a full dam, pray for those affected by flooding and love our neighbours in how we use our precious fresh water - and in how we minimise our climate impact.


Mike W said...

And let us not reopen calls to build the dam wall higher, destroying more wilderness, so that we can put more houses on the floodplain.
I remember that environmental fight from the 90's

stef said...

Speaking as an overseas Australian about to get on a plane again - do you know any worthwhile carbon offset schemes that are actually going to keep carbon out of the atmosphere for a long time? We would definitely be interested in a program that was effective. Thanks.

byron smith said...

Stef - There is a lot of debate around carbon offsetting and no options are perfect (some may only be slightly better than nothing), so it remains the case that the only real offsets are not getting on the plane in the first place. That said, I don't think that flying is an unequivocal moral evil never permitted (the ethics of flight is a post for another day - and I've been planning for a while).

I don't have specific company recommendations, but I will offer a few thoughts. There are three basic kinds of offsetting:

• Tree-planting schemes: In the past, many of these had very poor oversight, meaning trees were planted in inappropriate conditions and without ongoing management and quickly died, representing a worse than useless investment. There is better accreditation today, but there is still the issue of ensuring that the scheme uses appropriate species. Finally, the benefits from tree planting are deferred for decades, and are highly vulnerable to future changes (if the forest is cut down, or dries/dies out due to climate change, then the benefit is lost).

• Development schemes (e.g. supplying renewable power to poor nations, or supporting energy efficiency programmes): These have many of the same benefits and drawbacks of other forms of international development. Ultimately, while they often don't actually reduce current emissions (e.g. building a wind turbine for a settlement without electricity actually adds to short-term emissions), they do represent an investment in improving human flourishing (at least potentially, depending on many other factors) in a way that (hopefully) avoids future emissions (if the same development occurred with fossil fuel power). Probably the best kinds of scheme here focus on long term infrastructure investments with ongoing and self-reinforcing benefits.

• Permit buy-backs: These are probably less well-known and consist of agencies that buy carbon permits on open compliance markets (like the EU carbon market) and then retire them from use, preventing their use by other polluters and so shrinking the total pool of carbon use in that market. Though somewhat more abstract than the other options, the benefits are immediate and measurable - as long as the scheme as a whole is working effectively (the EU market has a few flaws that reduce its effectiveness).

In general, I would be very hesitant about schemes offered by airlines themselves, who have a vested interest in picking schemes with very low prices (and many have a poor or mediocre track record). If you are paying only cents or a couple of dollars per tonne, then you are probably supporting something that isn't very effective.

byron smith said...

But lying behind these questions are more serious debates about the desirability of offsetting and its effects on the moral culture. In particular, I would question whether supporting the offsetting culture is a positive move when it is clear that it is far more important that rich people directly tackle their own footprint and contribute to political change in their own backyard. So while I think that offsetting can do some small good and represents a retrieval ethic (trying to salvage something good out of a harmful situation), offsets come a long way down the priority list and if they become anything other than peripheral then they risk becoming another distracting tokenism from the real challenges. I'm not at all saying this is true for you, but a culture obsessed with offsetting is one that is probably not doing the hard yards and so there is a moral risk associated with encouraging this culture.

In sum, I think that probably the best course of action is to continue to seek to reduce one's own footprint as far and fast as possible, to continue political support for radical policy changes (or incremental changes that work in large increments!) that seek to avoid radical climate outcomes, to continue support for thoughtful international development (as you guys do in far more direct ways than most of us!), and then to "sin" boldly (in Luther's phrase) without supporting a culture of modern day indulgences. (Nonetheless, I'm not totally opposed to offsetting by those who do so in good faith, and so see advice above in the selection of a reputable and accredited company.)

byron smith said...

PS As I said, I've also been planning a post on the impacts and ethics of flying, though this is a complex, controversial and sensitive area (not that that combination of features has stopped me wading in with both feet before...).

In lieu of some of the calculations I plan to include in such a post, I thought I'd let you know that according to the formula I've come to use for flying, a single trip from Hanoi to Sydney (single passenger economy class) would generate climate effects equivalent to

7762.57 km x 1.09 x 1.9 x 82gCO2e/km = 1,318.26 kg of CO2e

That is, about 1.3 tonnes. For comparison, the average annual Australian footprint is about 18 tonnes.* The average Vietnamese footprint is 1.12.** The global per capita CO2 average is about 4.5 tonnes. We probably need to get to a world average of about 1 tonne per capita.

*This excludes imports (consumer goods), exports (coal!) and all aviation (!) and is only for CO2, not CO2e. The likely Australian CO2e per capita footprint taking these into consideration is more like 28, though this number is considerably harder to calculate and depends on a number of more contestable assumptions.
** CO2 only.

byron smith said...

Stef - I've just posted a significantly longer version of these comments.

byron smith said...

SMH: "A bureau climatologist, Aaron Coutts-Smith, said higher-than-average rainfall was likely for NSW until May, particularly west of the Great Dividing Range. The main cause was an unusually warm eastern Indian Ocean. "It's providing extra moisture in the atmosphere which can then fall as rain.""

Unusually warm ocean? Who would have thunk it...

byron smith said...

CSIRO & BoM release State of the Climate 2012.

Here is the relevant section on future projections, which I think is largely unchanged from previous expectations.

"Australian average temperatures are projected to rise by 0.6 to 1.5 °C by 2030 when compared with the climate of 1980 to 1999. The warming is projected to be in the range of 1.0 to 5.0 °C by 2070 if global greenhouse gas emissions are within the range of projected future emission scenarios considered by the Intergovernmental Panel on Climate Change. These changes will be felt through an increase in the number of hot days and warm nights, and a decline in cool days and cold nights.

"Climate models suggest long-term drying over southern areas during winter and over southern and eastern areas during spring. This will be superimposed on large natural variability, so wet years are likely to become less frequent and dry years more frequent. Droughts are expected to become more frequent in southern Australia; however, periods of heavy rainfall are still likely to occur.

"Models generally indicate an increase in rainfall near the equator globally, but the direction of projected changes to average rainfall over northern Australia is unclear as there is a lack of consensus among the models.

"For Australia as a whole, an increase in the number of dry days is expected, but it is also likely that rainfall will be heavier during wet periods."

byron smith said...

SMH: Climate change and the big wet. The record-setting last 24 months still only makes up about a third of the rainfall deficit since 1997.

byron smith said...

Age: Climate change likely influenced recent Oz floods, though it may take a decade to get a sense of by how much.

byron smith said...

The Conversation: A land of (more extreme) droughts and flooding rains? An excellent intro to the hydrological effects of climate change on Australia. First in a series.

byron smith said...

Part Two in the same series.