Andrew Wilson ("ACT government too fluffy on dual occupancy code", Times2, November 25, p5) stated that "the restriction of plot ratios to 35 per cent for dual occupancies defies all logic". In fact Andrew is not correct; while it is true that this restriction applies where one property is built behind the other, where both properties are "Built directly on the street", the plot ratio can be up to 50 per cent and double storey. This of course makes no sense from a solar access perspective, is not in keeping with current neighbourhood character, and unnecessarily restricts good architecture. This also causes a significant impact on current streetscapes and amenity.

This is, in fact, terraced housing and will cause "Sydneyfication" of Canberra's suburbs. Unfortunately, when people get upset about the on the street bulk of properties in their area, it might well see an end to dual occupancies development yet again. This would be a great shame as sensible dual occupancies development across the city will create jobs, housing choices and improved environment and solar advantages if both houses did not have to be built directly on the street.

We have to ask why Andrew was not aware of this and it is easy to understand – if you read statements by minister Mick Gentleman and the Asbestos Taskforce you will see mention of dual occupancies that are 35per cent, single storey and with "street frontage" (whatever that means). It is very hard to find any mention of 50per cent double storey, built directly on the street. Also, if you had asked (as I did) the chairwoman of the inquiry into DV 343, Meegan Fitzharris, MLA, if she was aware of it you would have discovered that she did not know either. How on earth has this all come about and why?

The sad legacy of this misunderstanding of such important design and siting criteria will have the unfortunate effect of stopping brown infill and dual occupancy development once again.

Lynn Russell, Yarralumla

I have been following with some interest the development of the light rail project in your fair city and I am quite staggered by the negativity that is displayed by some members of the ACT public.

Having spent my early years in Melbourne I cannot speak more highly of this mode of transport as an efficient means of moving vast amounts of people in very short space of time with minor disruption to other road users.

There has been some comment by "Can the Tram" regarding the advantage of heavy rail over light rail and I can't for the life of me understand how anyone could, not only compare the two, but suggest that heavy rail would be more suitable. Vast amounts of land would be required to build an effective heavy rail network and the rolling stock is far more expensive than that required for light rail. Then there is the infrastructure such as station buildings, level crossings and bridges as well as car parking facilities. It can cost around $45,000 to build one car parking space and there would be quite a few required whereas this would not be a consideration for light rail!

There is talk of light rail being reintroduced in Perth in the near future and I can't wait for it to arrive. We are fortunate that we have a decent bus system and an acceptable heavy rail network. When all these elements are combined the dependence on the motor vehicle as means transport will diminish markedly.

I can't help thinking that the most vocal opponents to the Capital Metro must have vested interests or maybe they belong in another era, a place in time when our mode of conveyance included a horse and cart.

David Apps, Wanneroo, WA

A. Smith (Letters, November 30) is correct to suspect that the light-rail project will be a net greenhouse emitter. The Capital Metro/CURF report lauded by minister Simon Corbell unaccountably ignored the over 60,000 tons construction estimate from Capital Metro, excluding pre-construction and congestion emissions. It also ignored the extra emissions from tram-created traffic delays after 2020, calculated from Capital Metro own model.

It exaggerated its "headline" annual 4700 tons savings by assuming only 25 per cent of current bus passengers would migrate to the tram, with the shortfall made-up by car travellers, inexplicably implying that the less attractive the tram was to bus passengers, the more attractive it would be to car drivers. With such methods, it estimated between three and five times more car travellers would migrate to the tram than Capital Metro's forecasts. Based on minister Gentleman's assertion that 1 million kilometres of bus travel will be "freed up" ("Light Rail to 'free up' buses for elsewhere", November 9, p2), and Capital Metro's own detailed models, the reality is net annual savings of less than 1600 tons of greenhouse gases to be offset against over 60,000 tons emitted during construction.

As bus and car emissions continue their fall to zero over the next 20 years, this will never be paid back.

Kent Fitch, Nicholls

Once again Michael Mulvaney (Letters, December 1), as one of the NIMBY apologists, does not like the truth to get in the way of his storyline.

Not once in his many ramblings on the Federal Golf club over many years does he mention that thorough community consultations that have been undertaken as well as several environmental impact studies which have showed little or no issues due to the nature of the land under consideration. All of these found that the effects of the development would have minimal impact upon the area and surrounds in question.

I have always been at a loss as to how such a small development would have such a detrimental impact on the whole of Red Hill and it would appear the surrounding suburbs.

I assume that Dr Mulvaney would prefer for this tract of land to be gifted to the Red Hill Regenerators group so that they can maintain it at their own personal cost in future as opposed to a much wider facility with demonstrable community benefits?

Surely, if there was to be a rationale conversation with this group, a compromise could be reached where both parties could achieve their respective goals through co-operation and understanding?

Chris Hume, Banks

Further to your editorial about the Paris climate talks ("Will world leaders seize the day on climate?", canberratimes.com.au, November 30), it is critical that there be an agreement to end subsidies for fossil fuels. Malcolm Turnbull has not signed it, constrained by the Nationals who do not want to lose the diesel rebate for farmers. That is understandable, though unfortunate, as we must make the shift as soon as possible away from fossil fuels and ending government subsidies would help a great deal. Perhaps farmers can be compensated in other ways since food production is critical.

Nevertheless, farmers must understand (as many do, not least wine-growers) that even two degree warming is very dangerous for agricultural production. Professor Lesley Hughes, a councillor on the Climate Council, says more extreme weather events, including longer droughts and more intense cyclones, are already affecting food production. She warns that the Murray-Darling Basin will be hotter and drier by 2030, with 2-5per cent less rainfall. Wheat will be sufficiently affected such that Australia may even become a wheat importer, rather than exporter, in the future.

It is time the Nationals came to the table to discuss these matters and, in the meantime, let our Prime Minister sign the agreement to end fossil fuel subsidies.

Jenny Goldie, Michelago, NSW

Energy efficiency plays a key role in reducing carbon emissions and thus addressing climate change. Judging by the actions of Malcolm Turnbull and Greg Hunt in Paris ("Paris UN Climate Conference 2015: Australia rejects fossil fuel pledge", canberratimes.com.au, November 30) and Julie Bishop back home, the Coalition is carefully allocating its own energies. More than 90per cent is devoted to spin, grandstanding, manipulating statistics, wedging the ALP, and placating climate deniers in their own ranks.

Ten per cent or less of their energy is used up doing anything significant about climate change.

Mike Reddy, Curtin

Both Don Clark (Letters, November 30) and H. Ronald (Letters, November 25) overlook a very important point in their letters regarding coral growth and its ability to keep pace with sea-level rise – unless the sea becomes too warm.

Low-lying, generally sandy islands, including those that are inhabited, are built on coral that is dead because it's covered by sand and/or other debris. If the coral is dead and buried (but not cremated!), it is not able to grow to keep pace with any sea-level rise. What usually happens is the islands gradually disappear beneath the briny, and the coral (if the water's not too warm) continues to grow in a ring around the now-submerged "island".

Douglas Mackenzie, Deakin

Don Clark (Letters, November30) cherry-picks contentious publications that are skewed towards support of a hypothesis that has had a corrupting influence on science as applied to public policy.

His citations can better be described as publications for political rather than scientific consumption.

Firstly, corals bleach for variety of reasons. Polyps consume their reservoir of algae under normal circumstances.

Secondly, corals are resilient. The last time they suffered enormous stress (far beyond the current alarmist fantasists envisage) was during the Permo-Triassic extinction 242million years ago. They recovered to dominate reefs. Why?

Rather than divide by 4, septa evolved to divide by 6.

North America suffered 120+ different episodes of major sea level fluctuation during the Cretaceous Period alone. Did corals disappear? No. They thrived as they do today.

Gerry Murphy, Braddon

We should be fair and let people keep what they earn. How can it be conceivable, that money people save for their retirement, costs the government money. The pensions that the government pays retired people costs the government money. It is perverse to claim that the retirement costs which our super pays – and the government does not pay, costs the government money. An easy fix to the super kludge ("Super's such a kludge", Forum, November 28, p2) is to make super contributions and earnings tax free, but tax withdrawals as earned income.

Bruce A. Peterson, Kambah

The Australia Institute says a reduction of the company tax rate from 30per cent to 25per cent would benefit bigger companies and their shareholders ("Company tax cut a win for only big end of town", December 1, p4). Really? In fact, shareholders would have to pay more tax.

For example, if a company's profit is $100 and the company tax rate 30per cent, and the resultant after-tax profit of $70 is paid out as a dividend, a shareholder on a marginal tax rate of 45per cent pays another $15 ($45 minus the $30 imputation rebate). If the company tax rate is 25per cent and the after-tax profit of $75 is paid out as a dividend, the taxpayer pays another $20 ($45 minus the $25 imputation rebate), $5 more.

The fact is that the tax the company pays is merely an "instalment" of the tax payable by the shareholder on the company's profit; and the less the company pays, the more the taxpayer has to pay as a final "instalment".

R.S.Gilbert, Braddon

I agree with Nicholas Stuart, that those Western leaders who are calling for a grand military action against the Islamic State are unlikely to achieve the desired outcome. His preferred approach, however, is to invite IS to the negotiating table ("Negotiation a necessary evil", Times2 December1,p1).

The problem with this idea is two-fold: Firstly, IS would conclude that it is unbeatable militarily. Secondly, it is likely to demand Iraq and Syria as its prize. Were this to happen, who is to say what would become of the Middle East as IS creates a Caliphate in the region.

I am afraid that whether the West goes for a war or settles for negotiation, the consequences of either decision are likely to be most unpleasant.

Sam Nona, Burradoo, NSW

Stephen Barnett's comments on the value of green open space in the inner city (Letters, November 30), the importance of caring for Haig Park, and the necessity for long-term vision, were timely.

Haig Park definitely needs protection, but it is heritage listed and this poses some limitations on its use. A few years ago, the government conducted community consultations and engaged Eric Martin to develop a draft master plan for Haig Park. This is waiting to be implemented.

Close to Civic, we have another large open space – Turner parkland – that is crying out for beautification and landscape development. This is the Sullivan's Creek green corridor running between ANU and Haig Park. This corridor is a popular pedestrian route into town and has the busiest bike path in Canberra.

The Turner Residents Association spent considerable time and effort opposing the annexation of part of Turner parkland for a bus layover, a battle we have, unfortunately, lost. We have continued to advocate for its development and gazettal as a park for the city west area, because of the large population of students and other residents, and the numbers of office workers who work there every day.

We urge the government to implement the landscape plan that was developed as part of the bus layover proposal.

Neil Parsons, president, Turner Residents Association

Despite Chief Minister Andrew Barr's recent upbeat assessment of the Constitution Avenue improvement program, I would suggest it is timely to consider calling in the Productivity Commission/ACT Auditor-General's Office to review the management and progress of the works undertaken so far. There are glaciers worldwide that advance and retreat at a faster rate than the progress we have seen so far.

Brian Rowe, Campbell

ABORTION

Since when was murder considered a "medical procedure", V. Harris (Letters, December 1)? Abortion is anathema to the Hippocratic Oath. V.Harris also completely missed the points of both John Popplewell (Letters, November 26) and Dr Alan Cowan (Letters, November 28), as neither of them purported to support "backyard abortions".

S. Redston, Chisholm

GIVING THANKS

Actually I disagree with Peter Burns (Letters, December 1). The point of Thanksgiving is not just about the Pilgrims, the point is that it is about giving thanks for the bounty of the land and the life we lead. It is more than "well meant wishes"; it gives Americans (and one day perhaps us) cause to stop and reflect on family and friends and the true riches of life.

Anthony John, Ainslie

So Peter Burns says the US ambassador shouldn't wish Australia "happy Thanksgiving from America" because we aren't an American state. Well, that's one way to look at it, albeit a mean-spirited one. Also his "Melbourne Cup" analogy is absurd. Perhaps the ambassador is simply reflecting America's high regard for Australia by wishing us well on one of his country's most important holidays.

Tom Lindsay, Monash

FREEDOM TO CHOOSE

You're absolutely correct, John Popplewell (Letters, November 26). The last thing doctors want or need is the freedom to ably assist Godless heathens attempting to wrest control over their own lives from the church, the state, and people like yourself, who know much better than they do exactly how much pain and suffering is good for them!

James Allan, Narrabundah

LESSON IN TOLERANCE

That Dr Ibrahim Abu Mohammed, grand mufti of Australia (who speaks very good English), finds it appropriate to hold a press conference in Arabic, should make us all understand what is quintessentially wrong with the way we Australians – by birth or choice – tolerate those who are clearly unwilling to tolerate our values and way of life, let alone identify with them.

Marian Moldoveanu, Frankston, Vic

DAVIS CUP

Frank Marris (Letters, December 1) says that "England's 80- year Davis Cup drought continues". England does not contest the Davis Cup. Great Britain, comprised of England, Scotland and Wales, has now won the Cup 10 times, the previous victory being in 1936 – 79 years ago.

Nick Stevens, Cook

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