In order to be an intelligent reader you must have a basic knowledge. Please do your own homework, a starting point http://www.InteliOrg.com/

GBR not bleaching due to temperature? Great! and thanks for keeping debate honest.
What news of ocean acidity?

"Rising levels of atmospheric carbon dioxide are causing the climate to warm and the oceans to become more acidic. Studies suggest that 20th century warming of approximately 0.6°C may have been beneficial to the growth of some corals and as a result masked the negative effects of declining ocean pH.
However, at some point water temperatures will exceed the thermal optimum for corals and when that happens both rising temperature and falling ocean pH will have a mutually reinforcing, negative effect on the ability of corals to build their calcium carbonate skeletons. Results from controlled laboratory experiments suggest that a doubling in atmospheric carbon dioxide could drive production of carbonate on many reefs below what is needed to replace skeletal damage from natural erosive forces."
http://www.sciencedaily.com/releases/2006/02/060220231628.htm

Suggesting acidity in Coral Sea naturally fluctuates more than previously thought:
http://www.abc.net.au/science/news/stories/s1470355.htm
Alarm from those subversives at The Times:
http://www.timesonline.co.uk/tol/news/world/article735077.ece

4 climate items in a row? What, no Muslim items in the locker?

Seriously how is anyone supposed to even read 4 seemingly identical items in a row. Yes no doubt there are nuances etc but just the titles tell us they are all about the climate. Which we, humans, can't fix.

Aren't there any other topics than climate and Islam?

What about a bit of bird flu, you know yesterday's fad topic used to frighten the public?

Nice article, that for a change looks at the science rather than the fairytale. I'm waiting for the alarmists to appear and contradict the author, predicting a Venus like global warming scenario where the seas will boil away leaving the coral exposed to die.

"What news of ocean acidity?"
Given that corals have lived through CO2 levels exceeding 2000ppm and most likely exceeding 4000ppm (compared with our measely 380ppm) I daresay this is a non-event as well. It may or may not affect other marine biota but corals will adapt.

I went to your listed web site Dr Coles - Most of what I saw was rhetoric and some what vitriolic - not a whole lot of science going on rather gainsaying at best.

A refreshing article which has the ring of truth.

The Reef is a great favourite with alarmists. I remember about thirty years ago, it was the crown of thorns starfish which was destroying the Reef and "needed urgent action".

The Reef is a perfect target for scaremongering global warming alarmists, and it is great to have the situation put into perspective.

I have visited the Reef many times over the years, so was aware that the greens were using their standard technique of finding a sick but insignificant part of the Reef and pretending, through photo techniques, that it was a universal problem.

It is reassuring to read an authoritative article from someone with the background and qualification of Peter Ridd, and it gives a handy reference to deal with alarmist nonsense.

I looked at the helpful website referred by Dr Coles, and would recommend that no one rely on the judgement of sneekeepete as to its substance.

An excellent article Peter.

It really is time to stop worrying so much about climate change and start concentrating on things that really matter such as population growth.

I would broaden this to continuous growth per se and overall sustainability. These are the things that need our immediate attention.

Climate change is proving to be a real distraction. All the new-found effort going towards climate change desperately needs to be steered towards genuine sustainability, of which continuous growth is a major negative factor.

We should continue to address fossil fuel consumption and alternative energy sources, but with the motive of avoiding enormous economic and social upheaval due to peak oil price rises rather than climate change.

If we were to do this, in conjunction with determinedly addressing the continuous growth issue (ie; directing ourselves towards a stable population and stable level of human activity), then we would be doing more for climate change than we could possibly do with the current approach, in which we are just unquestioningly accepting this continuous expansionism.

As for the Great Barrier Reef, I am pleased that it is very healthy all-told and not facing any serious threats at all…..except perhaps in some places from oil drilling (and spilling), as there are apparently large reserves under it. This is something which is bound to become more significant as oil prices rise and shortages loom.

I have two thoughts on this. First thought is that in 2002 the sea surface temp at Palm Cove (I am in Cairns and this is a northern suburb of our city) was 38C. This occurred for a few days in January. The water was like a hot bath and things were not normal.
Secondly if temps rise here by a few degrees they put the water in the same league as at 10 degrees south of the equator. Coral survives fine in these temps.
The point I am driving is that a majority of coral will survive at elevated temps. It is the inshore coral that exists in a smaller water pocket that will be destroyed. This seems the likely event if temps keep rising. They will be wrecked by greater extremes. It is a bit like people in Sydney putting up with a 45C day which occurred a couple of years ago. The trees in your garden survived OK but the maiden hair and other delicate plants were buggered. Same with the Barrier Reef.

Peter Ridd knows much more about the physical conditions of the Reef than I do so I accept his comments that it is in good shape without argument. For me however the connected issues he raises are more important - population and the condition of the land adjacent to the Reef. The condition of the Reef is just another example of the importance of maintaining population levels low. It matters not what problem in the world you watch or read about, it is almost always exacerbated by the frightening population growth. For example what hope is there that a country with nearly half its population less than 15 years old will be able to provide a decent education for tham all? Just try an experiment for a week or two. count the number of world problem that are mentioned that are made far worse by population growth. You will need lots of hands for counting!
I live adjacent to the Reef and have been involved in conservation/environment issues for 30 years. The condition of the catchments along the Queensland coast is poor. Weeds are a shocking problem, river banks are denuded, feral animals are rampant, some vegetation types are nearly gone - examples are wet schlerophyll and fresh water wetlands and so the awful list goes on. I am unable to rack up a lot of concern about a set of possible threats to a fraction of the Reef when all the catchments are so bad. worse is the fact that cash poors into Reef management and little goes into, for examlpe weed control. And now the ARC for weeds is probably going to be scrapped. Crackpot prioritisation.

Good article, Peter. People like you are doing what the Australian Democrats under Don Chipp once did, namely, keeping the b#st#rds honest!

Ocean acidity: this is another example of scientific exaggeration. In recent geological time - the past few million years - our oceans have never been acidic; they've only been less alkaline. A pH higher than 7 is alkaline, a pH lower than 7 is acidic. Current ocean pH is about 8.2. The worst prediction I've seen is that, under higher atmospheric CO2 levels in 100 or so years time, the pH may drop to about 7.7, although most authors indicate 7.9 to 8.0 is more likely. Whatever the actual number, the pH will remain alkaline and will not become acidic, which is the implication that some alarmists want you to believe. While a pH change of even this small magnitude will have environmental implications for corals and other marine life, there's one thing that won't happen: our oceans won't turn to acid.