Hyperventilating our way to the greenhouse talkfest

The brinkmanship displayed by Scott Morrison in trying to achieve a credible climate policy so close to the Glasgow conference is a sign of leadership weakness (“Warning to Nats on net zero failure”, 15/10). It exposes the reality of the Coalition, where a minority of members and a minority party that gains less than 5 per cent of the national vote determine Australia’s future.

After a decade of wasted economic and environmental opportunities, it seems that the best the Prime Minister will take to Glasgow will be a litany of slogans and spin, hoping that by focusing on Labor’s inconsistency and big polluters such as China and India no one will notice.

William Chandler, Surrey Hills, Vic

I am mystified by this new-found hope in hydrogen for a carbon-free energy future. Manufacturing hydrogen needs a lot of fossil fuels or plenty of electricity. Neither avoids CO2. Reducing water vapour to hydrogen in the quantities required would need a huge amount of electricity, more than planned fuel cells could produce.

In the past 30 years in Australia we have spent the best part of $60bn, much of it taxpayer-funded, on solar and wind yet we have transitioned our dependence on fossil fuels for electricity generation from only about 90 per cent to 80 per cent.

No new hydro capacity has been constructed in this period.

Richard Corbett, Mosman, NSW

The drive towards an Australian net-zero goal is politically unstoppable, but Nationals members calling for avoidance of a hard target are being realistic given the lack of certainty in climate models projected to 2050.

As experience showed with our ill-fated 30-year contract with France for submarines, it is vital that clauses requiring evaluations and staging points be included.

One major risk in committing trillions of dollars to net-zero ambitions between now and 2050 is the possibility that global climate change is not just controlled by anthropogenic CO2 but also by natural cyclic phenomena over time lengths of 50 to 200 years.

Australia unfortunately does not have any academic group studying these phenomena, although other countries, such as the US and Germany, do.

Observational data provides compelling evidence that atmospheric CO2 is not the sole criterion controlling climate-related phenomena.

The extent of Arctic ice has increased 18 per cent in the past year, with the rate of decrease flattening on a 10-year trend; Great Barrier Reef coral growth has reversed past bleaching and is now at a record high; and rainfall in southeast Australia shows long-term oscillations since 1860 of length about 90 years, suggesting that the drying trend since 1990 may be just a natural part of that longer oscillation.

Michael Asten, retired professor of geophysics, Hawthorn, Vic

Judith Sloan is correct (“Sorry, Bob, the time is ripe for nuclear”, 12/10) in criticising Bob Carr for rejecting nuclear on financial grounds.

He obviously has not seen a proper engineering costing of the various methods of generation. These take into account all potential costs during the life of the product, including end-of-life disposal, and apply an appropriate discount rate to future costs. Such a costing shows that nuclear is the cheapest, which is why France, with almost 80 per cent nuclear generation, is supplying the cheapest electricity in Europe.

Coal is very close in cost to nuclear but renewables are right at the other end of the scale as most expensive. The supply system, to remain stable, requires the input to be equal to the demand at every moment of every day.

Because of this, renewables will always be the most expensive as they are intermittent and therefore require continual standby backup ready to immediately supply any drop in energy generated.

E. Robert Y. Smith, Roseville Chase, NSW

It is conceivable that our global reputation and some of our exports will be at stake if Australia fails to commit to a net-zero target at Glasgow. Furthermore, any less than wholehearted action to achieve this goal on the part of the Coalition government is likely to have negative electoral consequences. The Nationals are right in being concerned about their constituents, but they must broaden their perspective in the interest of the nation.

Michael Schilling, Millswood, SA