There is much to be said for a happy life among the gum trees

There developers raze old gums to the ground, decimating wildlife habitat and creating deserts of close-pressed brick veneer dwellings.

On a recent drive I noted not one garden or streetscape has been planted with Australian natives. There are no tall trees. Research shows that in the summertime the temperature on the ground in such suburbs will be up to six degrees higher than in my gum-dense home in Emu Ridge.

I intend to plant two more large gums to further shield my house and street from climate change. This will add to the native canopy that helps support possums, crimson rosellas, butterflies, dragonflies, blue banded bees, wattle birds, silvereyes, eastern spine bills, squirrel gliders gliders, southern boobook owls and blue-tongue lizards.

James Coats (Letters, December 1) refers to gum trees as "awful"; "ugly and sprawling, needlessly high, and poisoning everything beneath them". He then claims that eucalypts "endanger life and limb with their treacherous habit of dropping limbs" and that "their shade is pathetic".

There are numerous eucalypts in and near my neighbourhood that seem to me quite beautiful. They drop very few, if any limbs, even in gale-force winds. They also throw a deep shadow that is very welcome in the sunnier months. As a bonus, they are frequented by, or are home to abundant birds of many species.

The flammability of eucalypts, which is matched by some fir trees, can be countered by keeping them well clear of buildings.

Gum trees will always be identified with Australia, and a welcome part of Australian life.

The atmosphere, being a gas, is a fluid. When a fluid is heated, convection currents arise which, in a gas, manifest themselves as winds.

Convection currents arise due to thermodynamic attempts to equalise the distribution of heat. The Earth also turns which causes coriolis, or twisting, effects.

The more heat is applied to this system, the more extreme the correction action necessary to return to equilibrium, giving rise to local events which are themselves more extreme. Ie: hotter, colder, windier, wetter, drier and so on.

That, roughly speaking, is weather.

Climate is determined by a place's location on the surface of the globe: latitudinal distance from the equator, altitude, distance from the coast and so on. But none of these is affected by global warming.

Additional factors which affect climate, not weather, are sea currents, such as the Humboldt current which cools Northern California and the Gulf Stream/North Atlantic Drift which warm the west coast of Scotland and keep the Hebrides and Orkney islands snow-free in winter. These and additional factors such as trade winds and sea currents are affected by global warming.

That is why we we refer to the atmospheric heating as climate change.

It's official: 2023 is the hottest year on record and global carbon dioxide emissions are at record levels. The analysis from the European Union's Copernicus Climate Change Service found this year's global temperature will be more than 1.4 degrees warmer than pre-industrial levels; close to the 1.5-degree threshold in the Paris climate agreement, and beyond which scientists say humans and ecosystems will struggle to adapt.

Goodness knows what 2024 will bring.

This points to the need for Australia and all the countries of the world to put their administrations on a war footing.

Surely nothing else is more important for the Albanese government, governments all around the world and all sectors of civil society than making the thwarting of global heating, biodiversity loss and other environmental issues a top priority.

It is often said "the market always gets it right".

The market is the invisible hand that delivers up the most cost-effective and efficient mix of resources by which production and consumption decisions are made.

But does it get it right?

In fact, the market fails big time. It has nothing to say about its externalities, namely negative impacts on our environmental ecosystems.

These impacts include, for example, water quality, air quality, threatened species, native forests, marine pollution, soils and human health.

The list is endless.

Only when producers and consumers pay the full cost of production, market and non-market, could we truthfully say the market gets it right.

The challenge is for economists to price the environment in a way which our politicians, and we who vote for them, can understand and believe in.

While the fallout from having to pay the full suite of costs may well lower our material standard of living, our overall standard of life would be enhanced and much the richer.

Stephen Saunders (Letters, December 7) was disingenuous in his criticism of Brian Schmidt.

He appears to confuse government policy with government factual data and appears to believe ANU management controls the research outputs of its academic areas.

While the landscape here is somewhat nuanced, academic freedom generally wins out in Australian universities, and it is difficult to see Professor Schmidt calling the shots with climate scientists and Crawford School economists. Suggestions of this nature deserve the label of conspiracy theories.

Kathryn Kelly claims "Palestinian Israelis experience apartheid" (Letters, December 6).

For starters, polls show that most Arabs who live in Israel describe themselves as "Arab-Israeli" or just "Israeli".

Only a small minority (7 and 8 per cent, according to two recent polls) call themselves "Palestinian". This would hardly be the case if they considered themselves to be the victims of apartheid.

There are no areas in Israel where Arabs can't live, or jobs they can't do. Arabs have been government ministers, Supreme Court judges, presidents of major banks, heads of hospitals and senior military officers.

All Israeli citizens have equal rights under the law. Perhaps Ms Kelly is thinking of Lebanon, where there are restrictions against Palestinians owning land or working in various professions.

Every nuclear power plant opened this century has taken more than a decade to approve, design, construct, licence and commission.

Countries with little or no nuclear experience such as Australia would likely take 15 to 20 years to commission a reactor.

It is highly unlikely that even if work started tomorrow, an Australian nuclear reactor could be connected to the grid before the 2040s.

Meanwhile, Australia's ageing and increasingly less reliable coal-fired generators are no longer able to guarantee the lights will stay on.

Per the landmark James Hansen et al. paper titled Global warming in the pipeline (November 2) under the present geopolitical approach to greenhouse gas emissions global warming will exceed 1.5 degrees this decade and two degrees before 2050.

Nuclear technologies are far too slow to contribute to the rapid transition towards a low-emissions future. People who suggest civil nuclear power generators would be a success in Australia if only the nuclear power ban were to be lifted are living in fantasyland.

What is with people like Simon Cowan and Peter Tulip (Panorama, December 2) advocating that people, meaning other people - not them, be jammed into cities in little boxes.

They advocate the demolition of lovely old buildings in city centres to make way for multi-storey blocks of flats.

There's no need to do this. All that is needed is high-speed, high-capacity, freeways to allow people to live in well-designed villages on the outskirts of the cities with enough room and sunlight for their kids to safely play, and to get to know the neighbours.

Increasing the average speed of travel to work from 70kmh to 100kmh would double the land available for housing.

Electric cars are here, what are we waiting for?