Well said mate, this silly argument comes up every single time and its been responded to that many times as well. I dont understand why people think it holds any water but your was a very good response

"There must be more useful things that people could do with their time than fuss on and on about these inevitable changes " - Apparently you dont have anything better to do, you dont see any irony in taking the time to comment no an article only to say that the article is unimportant and a waste of time......you dont think thats the lest bit self defeating?

Mr Dean, ever since you found out that the grade of fuel used by jet aircraft is called "Jet A1", you have bandied the phrase "Jet A1" into EVERY SINGLE CONVERSATION to which you have contributed. Matter of fact, it's about the only thing you ever contribute.

Rest assured that technologists are labouring away on replacing fossil-based liquid fuels with biofuels, thereby making redundant your sole contribution to these discussions. Perhaps you could be of some use to the discussion if you kept the rest of us all apprised of developments in biofuel technology.

No idea what change a few degrees might cause? Try living on the Ganges Plain.

Gerard Dean is the hypocrite here in that he talks about ethics but fails to disclose that he is a climate science denier and a fan of Andrew Bolt.

See his comment here "I deny that humans make a large impact on the climate..."
https://theconversation.edu.au/an-incumbent-industry-beginning-to-squeal-9907#comment_79376

His claim "Perhaps the rights of children to live in a safe, healthy environment, free from climate change is not as important as their regular overseas holiday?" is part of his usual faux concern trolling schtick.

John Nicol: the arch nemesis of logical and evidence.

I see you are back at the old doubt mongering game John. You really should stop using examples of local weather as climate, they are different after all. Your statements are akin to me spotting a basketball player and saying that the average human height is 200cm. Any decent scientist would actually see the normal distribution of measurements and then assess the changes over time, not try and look at the outliers or a single observation.

And then you pull out the classic 'climate has always changed' meme. Amazing. All those climate scientists must missed all of the natural cycles that climate goes through and not taken that into account when they were writing up all that science. But where did you hear about these natural cycles from exactly? Oh, that would be those climate scientists who measured them all and worked out what impacts they have....

Gerard Dean: "I will repeat the JetA1 fuel argument ..."
Dishonest trick #6, I believe:
http://www.hebrew4christians.com/Clear_Thinking/Informal_Fallacies/Tricks/tricks.html

Why are you so terrified of honest discussion on this topic? Or are you just attention-seeking?

You are getting less than 2-1 odds on an event that is 37% chance of happening?

37% is way higher than expected odds if there was no warming trend.

Climate science for Business School Dummies.

Observation 1. Sun irradiates earth with short-wave energy.

Observation 2. Earth re-radiates long-wave energy.

Observation 3. Greenhouse gases retard transmission of long-wave energy, not short-wave energy.

Observation 4. Arctic sea ice is melting, so that summertime sunlight is being absorped in exposed ocean rather than reflected off ice.

Observation 5. Greenland and Antarctic ice is melting, increasing the rate of sea level rise. The rate of ice melt is accelerating as atmospheric greenhouse gases increase.

Observation 6. In the Arctic, tipping points have been crossed. Permafrost is thawing, releasing stored methane and carbon dioxide, and warming Siberian continental shelf is causing release of methane from submarine methane clathrates.

Inference 1, drawn from observations 1, 2 and 3. Greenhouse gases thus regulate earth's temperature. Altering atmospheric greenhouse gas content therefore alters earth's temperature.

Inference 2, (drawn from inference 1 and observations 4, 5 and 6). Ocean is thermally coupled with atmosphere, and transfers a lot of heat to both Arctic and Antarctic.

Root cause analysis 1. Historic fossil fuel use and cement production data (Oak Ridge National (US) Laboratory Carbon Dioxide Information Analysis Center) shows sufficient CO2 emission from 1800 to 2007 to raise atmospheric CO2 from 280 ppm to 430 ppm. Dissolution of CO2 in oceans has limited atmospheric CO2 to about 390 ppm, and decreased ocean pH.

Some for me. "internationally agreed target of 2°C." Certain for the author. I cant find anywhere in the article any mention of uncertainty. In the Hansen NASA quote "denial of the truth exposes them to even greater risk.". Truth is a concept that imbues certainty.

Spiro: "My point is that rather than asking policymakers to waste taxpayers money on some very dubious propositions, you should use your own money if believe with certainty that predictions of climate catastrophe are true."

Spiro, your point is among the most abject misunderstandings of the issue that I have ever encountered. Not only do you demonstrate blithering ignorance of climate science, you also do not understand that the earth's climate system directly affects everyone: me, you, your bookie, the public officials who decide allocation of public funds, and the students who are being ripped off by accumulating HECS debts while in receipt of your curious notion that the common interest is insufficient reason for expenditure of public funds.

Spiro: "blah, blah, blah".

Thanks for that, Spiro, the most vapid and most amorl exposition of value-free neoliberalism I have yet encountered.

A bit of a catalogue of errors and fallacies there Geoffrey.
1) Climate change and weather events don't just "occur". They occur for reasons, to do with the conservation of energy, albedo of the earth, orbital cycles, levels of greenhouse gases, prevailing weather patterns, etcetera. The search for reasons is one aspect of science. The causality behind previous long-term changes is well understood (google "Milankovitch cycles"). We are not in the warming part of a Milankovitch cycle. We are not in a period of anomalous solar activity. We have not had any supervolcanoes, asteroid strikes, unusual levels of cosmic rays, etc. What we have done is dramatically increased the level of greenhouse gases in the atmosphere. These gases trap heat. It has gotten warmer at precisely the rate we would expect if these gases were doing what basic physics and chemistry tells us they do. QED.
2) Greenhouse gases have not increased linearly over the last century. Their biggest increase has been since the general industrialisation of production post WWII. In the 40s-70s, that increase in production was accompanied by huge increases in aerosol pollution (coal dust, ash, etc) which partly cancelled out the warming by blocking radiation. Furthermore, I don't think you quite realise just how much energy it takes to warm the whole planet by 1 degree. It is huge, not something that occurs without easily detectable causal agents (see 1) (one analogy found on line: the energy equivalent of 1.3 BILLION one megaton atomic bombs for every one deg C rise in the temperature of the worlds oceans.)
3) Your 15 year period a) ignores that most climate scientists agree that it takes ~30 years for a meaningful climactic trend to be unambiguously identified above random noise and b) relies on starting in 1997-8, an infamously hot year caused by a much larger than normal El Nino effect, itself probably driven by global warming.
4) Future projections are based on computer models - what do you think they should be based upon? Tea leaves? Computer models are just a way of doing maths very very quickly. You can work out the expected rough average temperature increase for the whole earth, given the increase in greenhouse gases, on the back of an envelope. The computers are useful for adding all the different non-linear factors (co2, methane, clouds, evaporation, atmospheric dynamics, aerosols, solar variation, etc), together to get more precise estimates, and modelling the effect of that general increase on smaller geographic areas and existing weather patterns. This demands a lot of maths.
5) Unproven assumptions - It is difficult to know what you mean here. That the universe is not run by a herd of invisible pink unicorns that just make it look as if we have gravity, conservation of energy, etc is an unproven assumption. Mathematics is, in certain ways, one big unproven assumption (google Godel's Incompleteness Theorem). Due to the three- and n-body problems, the idea that the sun will rise tomorrow without the earth suddenly being knocked out of its orbit by some chaotic strange attractor embedded in the solar system's gravitational dynamics is an unproven assumption. That Great Cthulhu will not arise tomorrow to eat your soul is an unproven assumption.
If you mean "the models are not as accurate as we can make them", however, this is clearly false.