At the end of March aerial surveys of more than 500 coral reefs from Cairns to Papua New Guinea revealed that the most pristine sections of the Great Barrier Reef are currently experiencing the worst, mass bleaching event in its history, with the overwhelming majority of reefs (95% has been quoted) being ranked in the most severe bleaching category.

Bleaching is caused by abnormally warm sea temperatures that have been boosted by the El Niño event that commenced in mid-2015 leading to sea surface temperatures more than 1°C above normal. These conditions are predicted to occur more frequently and more severely as greenhouse gas concentrations in the atmosphere increase.

As ocean temperatures have not cooled down yet in the northern section it is too early to tell what the long-term implications of this event will be. This depends on how soon ocean temperatures reduce and the time before another event occurs. Reefs need about ten years to recover.

The Great Barrier Reef has experienced mass coral bleaching events in the past. In 1998, there was a global mass bleaching event where 50% of the reefs on the Great Barrier Reef were affected. During this time, sea temperatures on the Great Barrier Reef were the highest ever recorded. Mass bleaching also occurred in 2002, with 60% of reefs were affected. This was the largest coral bleaching event on record.

In both the 1998 and 2002 events, the vast majority of corals on the reef survived, as sea temperatures came back down again in time for them to recover. About 5% of the Great Barrier Reef’s coral reefs experienced coral die-off in both these events.

What is Coral Bleaching?

From www.globalcoralbleaching.org

Many types of coral have a special symbiotic relationship with a tiny marine algae (zooxanthellae) that live inside corals’ tissue and are very efficient food producers that provide up to 90% of the energy corals require to grow and reproduce.

Coral bleaching occurs when the relationship between the coral host and zooxanthellae, which give coral much of their colour, breaks down. Without the zooxanthellae, the tissue of the coral animal appears transparent and the coral’s bright white skeleton is revealed. Corals begin to starve once they bleach. While some corals are able to feed themselves, most corals struggle to survive without their zooxanthellae.

If conditions return to normal, corals can regain their zooxanthellae, return to their normal colour and survive. However, this stress is likely to cause decreased coral growth and reproduction, and increased susceptibility to disease. Bleached corals often die if the stress persists. Coral reefs that have high rates of coral death following bleaching can take many years or decades to recover.

Global Coral Bleaching

In 1998, a huge underwater heatwave killed 16% of the corals on reefs around the world. Triggered by the El Niño of that year, it was declared the first major global coral bleaching event. The second global bleaching event that struck was triggered by the El Niño of 2010. The US National Oceanic and Atmospheric Administration announced the third global bleaching event in October 2015 and it has already become the longest event recorded.

The new phenomenon of global coral bleaching events is caused by ocean warming (93% of climate change heat is absorbed by the ocean). Corals are unable to cope with today’s prolonged peaks in temperatures – they simply haven’t been able to adapt to the higher base temperatures of the ocean. Although reefs represent less than 0.1% of the world’s ocean floor, they help support approximately 25% of all marine species. As a result, the livelihoods of 500 million people and income worth over $30 billion are at stake.

What can be done?

A major global bleaching event is considered one of the most visual indicators of climate change. Clearly the current experience demonstrates the importance of taking action to reduce greenhouse emissions. Apart from the potential loss of thousands of jobs in the tourism sector future generations could miss out on experiencing this environmental masterpiece. In the face of this situation the announcement on 3 April by the Queensland Government of the go ahead for the development of the largest coal mine in Australia is hard to fathom.

Adani’s own figures are that the mine and the burning of the mined coal will emit more than 4,600 Mt CO₂ over its 90 year lifetime. The Australia Institute has estimated that average annual CO₂ emissions will be 79 Mt. Australia’s current annual emissions are around 600 Mt. Many conditions have been placed on the mine and port operation aimed at limiting direct environmental damage but nothing can be done to stop the long-term damage from burning the coal.

There is still some legal action being taken by the local Aboriginal land owners and the Australian Conservation Foundation is taking action based on Australia’s commitments under the world heritage convention, which dictates Australia ‘do all it can to the utmost of its resources to identify, conserve, present and transmit to future generations the outstanding universal value of the Great Barrier Reef world heritage area’ – and that this must be the primary purpose of management of the area.

It says Environment Minister Greg Hunt ‘made an error of law’ by characterising emissions from transport by rail, shipping and then the burning of the Adani coal overseas as ‘not a direct consequence of the proposed action’.

The other hope for stopping the mine is that the falling price of coal will risk the financial viability of the coalmine so that bank finance will be unavailable. Dredging of the port at Abbot Point cannot commence until finance is secured.

Technological developments have had profound impacts on our lives, some good and some not so good, some with immediate benefits but unforeseen damage in the longer term. The internal combustion engine has transformed our lives from the horse and buggy era to almost total dependence on the use of motor cars.

Motor cars dominate our land use because of the need for roads, parking, service stations, car retailers etc. There is the health cost of fossil fuel particulate emissions and transport is a major contributor to greenhouse gas emissions. There are pollution and social costs from the inefficiencies and stress caused by congestion.

There is currently some debate about the effects of driverless (autonomous) cars. I will leave discussion of the economic effects such as changes in employment to the experts. Here are a few of the arguments for and against driverless cars from the social and environmental point of view. I am interested in hearing your views.

Reduction in Congestion

One of the chief arguments in favour of driverless cars is that they will lead to more efficient use of roads. Driverless cars could communicate with each other and traffic management systems and permit greater numbers of cars to get through a particular stretch of road. This is hypothetical in that it hasn’t been proven with real-world traffic and real driverless cars yet, but it has been well modelled, and there is little reason to doubt that in general this is true.

Driverless cars, it is believed, won’t get in accidents with anything like the frequency or severity of human-driven cars. This will reduce overall congestion, as well as death and injury, personal and financial costs.

Vehicle Efficiency

It is believed that most urban driverless taxis, and perhaps private cars, will be fully electric for reasons that are not primarily environmental.

Electric motors offer safety advantages (they can be used for emergency braking and to some degree for emergency steering). They are also much more durable (an electric motor easily lasts 1 million kilometres), less expensive and less complex than conventional engines. (Currently the reason for the high cost of electric cars is the expense of batteries.) In addition some driverless taxis operating in local traffic, primarily during peak hours, will not need huge battery packs. During idle times they can drive themselves to the next high efficiency charging station as needed.

There can be no doubt that driverless taxis and buses can change the nature of urban mobility. Much more short-distance travel will occur in small, lightweight, extremely energy efficient driverless taxis. Although this may lead to an increase in total miles travelled, the following effects combine to reduce greenhouse gas emissions because driverless taxis will:

• be mostly electric which reduces carbon emissions (provided the electricity comes from renewable sources)
• be smaller and much lighter than the average car which further reduces energy consumption per kilometre
• reduce demand for private cars and the total number of cars and therefore reduce the sizable greenhouse gas emissions during vehicle manufacturing which are typically more than 10% of total life-cycle emissions of a car (according to some estimates, a self-driving car-sharing vehicle or taxi can eliminate seven to ten private cars)
• facilitate multi-modal travel (taking a taxi to the train or bus station, continuing with bus or train)

More Efficient Use of Cars

How will driverless cars change the way we get around? The future may not be in private ownership but in mini-buses and taxis. The response of individuals is hard to predict.

Already there is a trend for people living in inner city areas where there is good public transport to forgo private car ownership. Car sharing services such as GoGet and internet call up services such as Uber are available to meet short-term needs.

Carpooling has been touted for decades as a way to use cars more efficiently. But it never took off because it suffered from an information problem: There was no way to know whether someone living around the corner was heading in the same direction as you, right this instant. It is much easier to drive yourself so many of us head off to work in the same direction with one or two people on board.

At the level of urban design and the environment, driverless cars could produce huge benefits. If cars can drive themselves, fleets of them could scurry around picking people up and dropping them off, working with sleek, robotic efficiency. With perfect computerised knowledge of where potential riders were, they could pick up several people heading the same way, optimising ride-sharing on the fly.

It’s possible that fleets of robocars could become so reliable that many people would choose not to own cars. The reduction in private use of cars could reduce the need for parking. Think of all that land that could be freed up and converted to recreation and green space.

Social Benefits

Driverless cars could enhance the lives of the disabled and older drivers by giving them greater independence although they may still need assistance at either end of their journey.

Questions

The effect of driverless taxis on public transport is not yet clear. There is both the risk that some local trips which are taken by public bus today will migrate to driverless taxis and the opportunity to capture a much larger share of the mobility demands with on-demand buses and mini-buses will not eventuate.

There has been talk of the nirvana of being able to call up your driverless car and, hey presto, your car will appear and take you to work or the shops, take your children to sport or pick them up from the late night party. You will be able to sit in the car and catch up with the work emails or have a snooze. Internet taxis and ride share services cost less because they are more efficient in matching up vehicles and passengers. Costs will become even less if there is no driver to pay. Transport to work will be so enjoyable that people will happily live in the outer suburbs and travel times will not be an inconvenience.

But, just a minute, if one extra person is driven rather than taking public transport won’t lots of people want to do this? Congestion is a non-linear function, so as a road approaches its maximum capacity, small changes in traffic volumes can cause proportionately larger changes in congestion delays. We see this in practice where reduced traffic during school holidays makes a major difference to travelling speeds.

Driverless cars somewhat mitigate this effect, but that doesn’t matter if the use of driverless cars means more cars on the road at the same time. Further, ride shares have to drive further than someone in a private car would in order to pick up their customers or return to their designated drop off points. Completely empty driverless cars on the road are not likely to reduce congestion if more driving is required.

And that’s where the rub is with driverless cars. There are differences of opinion about how driverless cars will actually operate.

Will people stay attached to private cars?

Many people like having cars and use them as handy storage and goods movement facilities. Will they be willing to give up the convenience of having a car immediately on hand? They are status signifiers to neighbours. They are places of privacy. They are cars whose sunk costs are turned into travel conveniences, with weekend trips to the beach and annual holiday trips made economical by having a car for commuting.

While many automotive theorists predict radical changes in human behaviour related to car ownership, there’s little reason to believe that people will become rational just because of a new technology. There may be an impact on private vehicle ownership, but this may not be nearly as big as other advocates suggest. And if this is the case, then there is little reason to expect a reduction in total car miles driven and car ownership.

Will a reduction in family cars increase total mileage driven?

While in general there is little reason to believe that there will be substantial decreases in ownership, let’s explore that model in case it comes true. Let’s identify a model family of mother who works in the city, father who does piece work at home and two children in school. In this model, the family’s single driverless car delivers the mother to work, then swings back and takes the kids to school, then swings back and takes the father to a mid-day yoga class, then unspools this at the end of the day. This does take a two family down to a one car family. Except it does it by up to doubling the total miles driven by the family, as the car goes two ways. Once again, congestion is strongly correlated to total miles driven by cars, and in this model an empty car is driving around with no one in it a lot of the time and the total miles driven by the family vehicle go up. That is likely to increase congestion.

Will parking outside the city centre increase the total distances driven?

Right now people who drive to work park at or very close to work. That’s pretty useful because they have access to their vehicle and it stops driving once they reach their destination. Under one model posited for driverless cars, the car wanders away to cheap parking outside of the core. The problem with this is that it once again puts more vehicle miles on the car which is strongly correlated to increased overall congestion. Imagine a bunch of empty cars on the roads at rush hour trying to get through city streets to cheap parking. And then there is the land required to be allocated for more parking space.

Will longer commutes become viable and so increase the total distance driven?

At present, commuting by car is highly unproductive time. Commuting by public transport is also problematic due to lack of power outlets and Wi-Fi and the inability to have private conversations. There’s a model of the future, however, in which driverless cars provide a private productivity zone, allowing people to live even further from work. Driverless cars promoting suburban living and long commutes increases traffic congestion and fuel use.

Conclusion

Driverless cars have the potential to reduce transport land use, congestion and greenhouse emissions. Do you agree?

References

http://cleantechnica.com/2016/01/17/autonomous-cars-likely-increase-congestion

http://www.driverless-future.com

http://www.newsweek.com/driverless-cars-and-future-parking-418943

http://www.newsweek.com/2016/01/22/driverless-cars-and-future-getting-around-415405.html

The population of the Sydney metropolitan area is estimated to grow by 1.6 million people by 2031. According to the NSW Government, Sydney will need 664,000 additional dwellings by 2031. This dramatic expansion is being driven by the Australian Government’s insane promotion of high immigration in pursuit of its unsustainable growth agenda. The NSW Government’s response is A Plan for Growing Sydney.

In STEP Matters, Issue 183, p4 (Concern about Changes to Biodiversity Laws) we explained the reasons for concerns about the NSW Government’s plans to rewrite the biodiversity laws. The new legislation is due to be released in March 2016 and the indications are that protections will be significantly weakened.

In the past, councils expended significant funds in formulating local environment plans with zoning locations appropriate for different areas. The particular zoning and its extent took into account the immediate and cumulative effects on local infrastructure, services, traffic, street car parking, social services and amenities. The matching development control plans gave consideration to the local character of the area, including streetscape, topography, shared views, and soils.

It now seems that the NSW Government is trying to overwrite these local powers by proposing a major expansion of medium density housing into low density housing areas. Details are provided in a discussion paper released in November 2015 called Options for Low Rise Medium Density Housing as Complying Development.

After promising that amalgamation would not be forced onto residents, the NSW Government is pressing ahead by moving the goal posts. Initially local councils needed to demonstrate to IPART that they were fit for the future. Then after the majority of councils did prove their financial fitness the Government imposed a minimum scale and capacity (population size) as the requirement.

The Ku-ring-gai Bushcare Association is an unincorporated organisation that is supported by Ku-ring-gai Council which supports the Bushcare volunteer program and holds regular educational events. The committee comprises elected volunteers and Council employees.

The Paris climate change talks in December 2015 produced an agreement hailed as 'historic, durable and ambitious'. Developed and developing countries alike are required to limit their emissions to achieve an objective of limiting average global temperature increases to 2°C with an aspiration of 1.5°C.

In November last year STEP held a talk by Dr Ian Percival on the unique volcanic diatreme that has been exposed in the Hornsby Quarry. The Geological Society of Australia and STEP made submissions to the Roads and Maritime Services about the project to use the quarry void to dispose of spoil from the NorthConnex tunnel. But while it appears that the upper two levels of the quarry will escape burial, so far we have seen little reference in any document to the enormous importance of this site as a scientific and educational tool.

STEP committee member, Andrew Little, happened across an Echidna searching for ants in a driveway in Roseville Chase. It was a concern that he had open shoes without socks at the time and so stood perfectly still. He describes the experience.

Mark Diesendorf, UNSW Australia

Can Australians be sustainable and enjoy endless economic growth? It’s not likely.

The Boomerang Alliance, a coalition of groups led by the Total Environment Centre, has been campaigning for more than ten years for the introduction of a drink container deposit scheme to reduce the appalling level of litter, especially along our waterways and highways.

Out thanks to the Ku-ring-gai Bat Conservation Society for permission to publish this article that was originally published in Friends of Bats newsletter in December 2015. It is written by Tim Pearson, a wildlife ecologist who is researching flying-fox communication for his PhD at Macquarie University.

Two members of the STEP committee visited the Snowy Mountains in recent months. John Martyn saw plenty of flowers in late-spring but my experience in mid-January was that most of the flowering had finished. Traditionally January and February have been peak season for flowers. More evidence of climate change? John’s perspective on his visit follows.

About a year ago the discovery of a new species of Hibbertia in was announced. The species, with the scientific name Hibbertia sp Turramurra and common name of Julian’s Hibbertia, was officially listed as critically endangered under the Threatened Species Act in September.

Sadly another STEP stalwart has died. Glenn Johnson was a member of the committee for nine years from 1984 to 1992. His fellow committee members describe Glenn as a sensitive person who loved the natural environment and who was passionate about his family, garden and work with the Royal Botanic Garden Sydney. He was a born teacher and explainer.

The Science Teachers’ Association of NSW conducts a program to assist students and their teachers to carry out scientific investigations. Since 1992 an annual award program has provided prizes for the outstanding projects. STEP sponsors an award for a project relating to an environmental issue.

Wander through the bushland of Wahroonga Estate and you will see the delicate heads of native orchids peeping out from between Sarsparilla (Smilax glyciphylla) and Old Man’s Beard (Clematis aristata). The first indications that orchid flowers are about to emerge are the tiny leaves – heart-shaped, ovular, arrow-headed – solitary leaves of a variety of shapes that carpet the ground.

Ross Rapmund gave a fascinating talk on the changing birds in northern Sydney. He started with a slide which compared the ten most common birds before 1900 with recent data. A hundred years ago the most common species were small birds with an average weight of 18 g (e.g. Superb Fairy Wren, New Holland Honeyeater, Golden Whistler and Willie Wagtail). Now the most common birds are much bigger with an average weight of 180 g (e.g. Common Myna, Noisy Miner, Magpie, Currawong and Rainbow Lorikeet).

The NSW Government is currently considering legislation to implement the recommendations of the Independent Biodiversity Legislation Review Panel contained in their report released in December 2014.