The professor's forecasts for light rail are even more dire and any chance of economic survival is dependent on high-density (vertical village) development along transport corridors; even so, bus rapid transit has more than twice the rate of return of light rail. One must wonder who is providing the government with advice on these matters.

Ed Dobson, Hughes

Jenny Stewart's reasoning about renewable energy costs and subsidies is perfectly sound, so her conclusions appear equally sound. The problem is that they are based on incomplete and faulty premises.

Firstly, fossil fuels are already the beneficiary of large subsidies of various kinds - most typically generous tax breaks - which total something like $8 billion per annum in Australia. I would refer anyone who objects to calling this kind of support a ''subsidy'' to Jim Yong Kim, the president of the World Bank, who is unequivocal in doing so. Subsidies to renewables merely ''level the playing field'' a little.

Secondly, the generally ignored externalities from the coal industry alone vastly outweigh any modest subsidies provided to renewables. For example, a major 2011 study in the US by Muller, Mendelsohn and Nordhaus showed that damages caused - to health and infrastructure - ranged from 1.4 to 3.5 times the value added. Coal causes more economic cost than the benefits derived from the electricity produced - and that's ignoring the human suffering.

Finally, it is almost impossible to calculate the precise costs of climate change but, as the recent IPCC reports indicate, they are large and could become crippling if we don't act rapidly and decisively to reduce emissions.

The 90 per cent target is the ACT's way of doing our share. Of course we need to be critical and economically rational in making decisions about renewables but, if we calculate from faulty premises, we will simply get reliably faulty answers.

Felix MacNeill, Dickson

I generally agree with Bob Salmond and M. Silex (Letters, March 27). Our proposed light rail system is supposed to ameliorate urban sprawl and facilitate housing affordability. But surely sprawl's not a problem here because we've got an excellent arterial road system (with cars getting smaller and cleaner), good bus services, tracts of land suitable for new family homes with backyards within the Spatial Plan's 15 kilometres-from-Civic development footprint, dispersed town centres, 90-square-metre secondary dwellings permitted on older suburban blocks, and convenient group and local centres (shops, schools, etc). Light rail here is about development ''land capture'' for ''urban villages'' near stations, like the Racecourse and Epic land on the proposed Gungahlin-Civic line. Those facilities will have to be expensively relocated to, say, cryptic noisy Majura. I'm certain the land capture retail prices won't result in affordable or suitable family housing for most.

Jack Kershaw, Kambah

The Canberra Times editorial (''Robust free speech will sometimes jar'', Times2, March 28, p2) saying that the law should not ''spare the feelings of a particular group'' implies that people subjected to racial abuse are unduly sensitive and should ''toughen up''. This is outrageous. Racial abuse attacks your identity, your sense of self and it is intended to hurt and humiliate. It is delivered with malice and forethought by people who believe themselves superior because of their race.

George Brandis believes the nursery rhyme ''sticks and stones may break my bones but words will never harm me''. Does he know how it feels to be abused because of your race? Does he know the harm done, which can be worse than a physical blow? We've outlawed bullying in schools and at work. Racial abuse not only harms mental health but also destroys our hope of community cohesion.

Like many other Australians, I have been on the receiving end of racial abuse and the word ''offensive'' does not come close to describing how it felt. Yes, Mr Brandis, racism and bigotry are about what people think and intent is a principle enshrined in our criminal law. A crime committed intentionally is viewed differently to one without intent; it's the difference between manslaughter and murder. It seems our major sporting codes are tougher on racial abuse than our federal government.

Chris Bourke, MLA, Canberra City

Alan Cowan (Letters, March 29) repeats the discredited view that racial vilification is no worse than political or religious criticism. Political opinions and faith views are free to be discarded, but skin colour or ethnic origins cannot be changed. Racial taunts would be far more traumatic than criticism of political views, especially if repeated on a regular basis. As for the obsessive hatred claimed to be directed at Tony Abbott, perhaps it is fitting given the hatred he made part of the regular political discourse in the previous parliament.

Derek Foster, Binjura, NSW

I note that Ian Warden (''Koels hear call of the tropics'', Gang-gang, April 1, p10) is a huge fan of the koels and that - thank goodness - they have finally departed for PNG, giving Canberra folk a well-deserved respite from their irritating wail. Now those who have endured interrupted sleep throughout the summer because of these birds can sleep beyond 4am. Let's hope they don't return too soon - or better, stay in PNG.

On a brighter note - and in case Mr Warden thinks I am a bird hater - I have noticed an increase in the population of the magnificent yellow-tailed black cockatoo in countryside around Canberra, and even around Yarralumla. This beautiful species was severely decimated during the Canberra fires, having lost their habitat of pine trees. However, they are making their way back and to hear their plaintive cry as I ride my bike around Uriarra is a joy.

Judy Diamond, Narrabundah

Could we give our Prime Minister a magic suppository of wisdom to wean him off his simplistic comments about the latest report from the Intergovernmental Panel on Climate Change (''IPCC speaks, but is the world listening?'', Editorial, Times2, April 1, p2)?

One can only feel deep despair at his utterances: the existing carbon price was a ''very dumb policy'' and that Australia is ''a land of droughts and flooding rains. Always has been, always will be'' (''Damage risk as planet heats up'', April 1, p6).

Abbott and his government don't get the bleeding obvious that extreme weather events are happening more frequently, with greater severity than before, and with dire consequences for the economy. If the economy is the Coalition's mantra, how will it cover the enormous costs of helping communities after wildfires destroy towns, when food crops fail and livestock die, when exports drop and food security for Australia is threatened, when tourism fades as the Great Barrier Reef coral is reduced to bleached skeletons, when our unique natural landscape and wildlife that feed the tourism industry are irrevocably changed from repeated droughts or floods? How will the government boost morale as the population battles the increasing vagaries of climate change?

Abbott seems hell-bent on jackbooting everything, repealing legislation which should protect the natural environment and human services. Please, Mr Abbott, don't say the Australian people have given you a mandate. I haven't.

Judy Kelly, Aranda

As discussed in the editorial, ''IPCC speaks, but is the world listening?'' (Times2, April 1, p2), the Abbott government is seemingly not very worried about the consequences of global warming. To at least some degree, this is a reflection of its doing the bidding of its corporate donors and masters, and taking the word of climate change sceptics and deniers who are on the payroll.

The Coalition's so-called direct action policy is little more than an exercise in tokenism, and, as many (including CSIRO) have pointed out, will not work. The extremely underdone ''Soil Carbons [sic] - once-in-a-century replenishment of our soils'' idea, in particular, is virtually meaningless: there is no indication given on how this ''replenishment'' and ''carbons'' capture is to be done.

All of us who care about the future of this country, and of the world, should be applying pressure on Tony Abbott and this government to do something meaningful to address global warming rather than ignore the science and spitefully undo almost everything the Labor government did.

Douglas Mackenzie, Deakin

It was troubling to see a gloating Tony Abbott and Immigration Minister Scott Morrison fronting the media beside a simplistic scoreboard registering 0 boat arrivals in their first 100 days in office. Labor vs Liberal with the scoreboard telling us Liberal are the hands down ''winners''.

Nil boats arrivals on Australian shores does not mean zero people arriving in offshore processing centres at Christmas and Manus Islands or zero boats towed back to Indonesia in the last 100 days. Lucky it's all about the boats. Michael Gordon's article ''Most Manus asylum seekers not genuine refugees, O'Neill says'', March 22, p4) reports that there are ''about 1300 detainees on Manus Island'' and that ''not one refugee status determination has been completed since the first asylum seekers were sent there in November 2012''.

If stopping boats is, as both sides of government state, about ''saving lives at sea'' … then it is critical to keep the ''at sea'' in that catch-cry; because on land, these people's lives are not being ''saved'' but suspended indefinitely in poor, sometimes dangerous (and in the case of Iranian asylum seeker, Reza Barati, even deadly) conditions. We are damaging people not saving them. There is no justification for treating anyone like this, genuine asylum seeker or not. Failing to protect people's basic human rights for safety, freedom and opportunity in a bid to win the sickening ''stop the boats'' game isn't gloat-worthy.

Alison Coster, Karabar

To the many people such as Alex Wallensky (Letters, March 31), please note that 90 per cent of asylum seekers who come by boat and have had the good fortune to be ''processed'' have been found to be genuine in their need for asylum.

Please do not be fooled into thinking that coming by boat means asylum seekers have loads of cash and are ''economic'' refugees. The current government's propaganda is well and truly alive each and every day.

Jan Gulliver, Lyneham

After all the beautiful colours she wore as Governor-General, the colour Quentin Bryce chose for her portrait was disappointing. However, more important in the scheme of things is going against God's law.

Receiving a title does not change this. I refer to the former governor-general's views on same-sex marriage.

Rosemary Lyne, Kingston

It is important that a ''fair call'' is recognised by all sides of politics. And Joe Hockey has made a ''fair call''. Whether or not anyone agrees on the nature or degree of the ''challenge'' which Mr Hockey tells us Australia faces, surely we should agree that the Treasurer has made a ''fair call'' when he stated that ''everyone in Australia has to help to do the heavy lifting in the budget, because if the burden falls on a few, the weight of that burden will crush them.

''Everyone is going to have to make a contribution - big business, small business, all people from all demographics across the community.''

Well said Mr Hockey. Most fair-minded Australians would agree with that assessment. But Mr Hockey, how will those whose families are blessed with a partner earning $150,00-a-year who becomes pregnant, make that contribution?

Ken Brazel, Weston

Assume that Medibank can be sold for the $4 billion or so being touted, being the capital value determined by a buyer, based on the perceived profitability of the entity, as indicated by current and historical dividends to the federal government. The government has three essential options: keep Medibank and maintain the status quo by taking the annual dividend into consolidated revenue; keep Medibank and use the annual dividend to service a large loan to pay for infrastructure (or other things); or sell Medibank, use the capital (after costs) and receive annual company tax (which almost certainly would be less than the current dividend paid to the government).

As an ordinary taxpayer, I do not have access to the figures to calculate the relative merits of the two alternatives, but the government does have the information and should publish these and present the relative financial benefits of keeping or selling Medibank.

M. Silex, Greenway

The National Capital Authority's reasons for trying to move Gaby's takeaway (''Takeaway to appeal after authority delivers marching orders'', March 28, p7) make no sense. Gaby's offers good value takeaway food in an area that lacks other similar options. However, the NCA claims that to ''encourage diverse eating establishments'' then any existing diverse eating establishments must go! Apparently only ''construction workers'' eat from takeaway vans (the hint being construction workers are not welcome to eat in the area any more).

After having worked in the Triangle for years, I can say that Gaby's offers the best value, best tasting lunch around. And guess what, I'm not a construction worker!

B. Sloane, Scullin

CLIMATE CHANGE

The editorial (Times2, April 1, p2) was headlined ''IPCC speaks, but is the world listening?'' The world will remain demonstrably deaf to the inevitable until it implements evacuation plans for New Orleans, the Netherlands and Bangladesh. Until then, enhanced disaster relief capability is the best expectable.

Gary J. Wilson, Macgregor

POLLIES' STUDY TOUR

So Canberra Liberal MLAs and staff need a two-week ''study'' tour at taxpayers' expense to check on sex-industry laws in other countries (''Studying how to toughen sex trade laws'', March 31, p1). Ever heard of getting information via the internet, email, Skype or even the telephone? In this era of job losses in Canberra it's good to see our pollies remain sensitive as ever. I suppose declaring it a ''feminist'' issue will scare off any criticism.

Tom Lindsay, Monash

CARTOONS DRAW FIRE

I couldn't agree more with Peter Baxter's comments (Letters, April 1) regarding the daily supposedly cartoons of David Pope. They are biased in the extreme and The Canberra Times needs to point him in another direction!

Rod Frazer, Garran

Please The Canberra Times, ignore Peter Baxter's advice to send David Pope to the sin bin. As long as we have to tolerate our PM's continuing cack-handedness and buffoonery, let's at least get a laugh out of it.

Judith Erskine, Belconnen

SMART METER FEES

Your front-page photograph (April 1) of the new smart meters shows the fee is $1.50 per hour if you park for 1, 2 or 9 hours but $5.50 if you park for 3 hours. Is this a mathematical error by the Office of Regulatory Services or is there some philosophical reason for charging three-hour parkers an extra dollar?

Geoff Clarke, Holder

BARRIER REEF THREAT

Early in 1970 the Queensland Trades and Labour Council banned drilling on the Great Barrier Reef, an action which Judith Wright lauded as ''magnificent and unprecedented''. Five years later, building unions banned mining on Fraser, calling it ''the anchor of the Reef''. Were a union to do either today, Gillard's Fair Work Act would impose a million-dollar fine. So it goes under the ALP.

Humphrey McQueen, Griffith

WHALING DECISION

The ICJ decision that Japanese whaling is not scientific research (Japan's Antarctic whaling banned'', April 1, p1) is utter rubbish. Japan has been rigorously researching how quickly whale meat can be delivered from Antarctic waters to the dinner table.

Thos Puckett, Ashgrove, Qld

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