No, reefs were lost during major extinction events caused by high levels of CO2 and runaway warming. Sound familiar?

Yes, and when they went away during periods of mass extinctions, they were gone for millions of years. Is Mr. Plimer suggesting doing away with the GBR for millions of years is an appropriate price to pay for short-term fossil fuel profits?

Quote that Colorado's snowpack was the worst in 30 years cites the January snowpack. The April snowpack is the measure of peak snowpack at the end of the season. It should have quoted https://www.denverpost.com/2018/04/05/colorado-mountain-snowpack-drought/ The conclusion would have been similar but not the more than 30 year figure.

I like the hopeful final paragraph. We can't give up yet but we definitely must act now.

The quote from Jon Brodie about giving up refers to government action on water quality and is dropped into the article with no context of how water quality fits into the rest of a story that is focused on global warming and bleaching.

In Brief says many portions are facing no hope for recovery. I think that's an overstatement. While the back to back bleaching has given some areas no chance for recovery, that doesn't mean they have no hope for recovery in the future -- especially based on what was known in April 2017 when this was posted.

I haven't heard scientists use the word terminal. The article infers that but doesn't cite a source. I'm not fond of the reporter using a term like terminal without a direct attribution.

This is rather overstated. While some weedy species may migrate poleward, studies have shown that corals cannot move to much higher latitude due to other factors such as the light corals require for photosynthesis and skeletal growth. Higher latitude corals will also be restricted to shallow water where they are more susceptible to cold stress.

Environmental Limits to Coral Reef Development: Where Do We Draw the Line? Joan A. Kleypas, John W. McManus and Lambert A. B. Meñez American Zoologist Vol. 39, No. 1 (Feb., 1999), pp. 146-159

This is corrected but it is important to note that the severe damage was restricted to the northern Great Barrier Reef.

The article overlooks the fact that not only was the bleaching on the northern Great Barrier Reef the worst on record, so was the bleaching in many areas around the world. In fact, the global coral bleaching event that is still underway is the longest, most widespread, and perhaps most damaging event on record.

Another important note is that the 1997-98 El Niño was much stronger than the 2015-16 El Niño. Even so, 2016 was much warmer than 1998.

This may turn out to be true but most studies place annual bleaching, especially on the GBR a bit further out, perhaps 2050. http://www.nature.com/nclimate/journal/v3/n5/full/nclimate1829.html

Correct http://www.sciencedirect.com/science/article/pii/S0272771408003405

Article should have noted that while injured and starving, bleached corals are still alive. When thermal stress is severe or prolonged corals often die. Thermally-stressed corals also frequently die due to disease outbreaks. http://coralreef.noaa.gov/gallery/infographics.html http://www.annualreviews.org/eprint/qtrxqRIr8GERt4WyRUDC/full/10.1146/annurev-marine-010213-135029

Skeletons, not shells. Far from the most articulate description but generally not wrong.

Correct, per official figure found below.

Again, confirmed by scientists responsible for the study. http://theconversation.com/how-much-coral-has-died-in-the-great-barrier-reefs-worst-bleaching-event-69494

Actually, this is an underestimate as the "25% of the worst affected reefs (the top quartile), losses of corals ranged from 83-99%." http://theconversation.com/how-much-coral-has-died-in-the-great-barrier-reefs-worst-bleaching-event-69494

The best reference for most of this paper is the 29 Nov. story posted on "The Conversation". Written by the scientists responsible for the work at James Cook University and co-authored by a high-ranking official of the Great Barrier Reef Marine Park Authority, this article contains the most comprehensive summary to date. http://theconversation.com/how-much-coral-has-died-in-the-great-barrier-reefs-worst-bleaching-event-69494

In general, Doyle Rice got this one almost completely right, with one of my two quibbles being in one of his experts' quote -- something Mr. Rice has to take at face value.

It is unfortunate, however, that Mr. Rice didn't put this in the context of the global coral bleaching event that is still underway -- currently hitting hardest in Micronesia and the Marshall Islands. http://coralreefwatch.noaa.gov/vs/gauges/eastern_fsm.php

This is another misstatement used in this article to overstate the actual findings. There have been discussions in the community about the best methods to use. Ocean acidification is a relatively new field and some early methods probably were not the best comparison against what will happen in nature. Newer approaches have improved on this. However, some newer studies also have found that methods such as acid addition can be just as relevant physiologically as bubbled CO2 methods depending on the hypothesis being tested. Thus, some methods thought to be less comparable to natural systems have been found to be perfectly valid in some cases.

This is an inflammatory twisting of the author's words. Browman discusses the well-known bias against publication of negative results. It has nothing to do with the direction of the signal, only the inability of the researchers to demonstrate an effect in their experiments. It has nothing to do with how "calamitous" the predictions are. In fact, sometimes the negative results would have been more calamitous depending on the experimental design.

Yes. There is a definite value in work like the issue Dr. Browman edited. The difficulty in publishing negative results in science can make it challenging to fully assess the sate of the science, especially in newer fields such as ocean acidification.

I concur with other annotators that this statement is much too weak. The consensus of the IPCC and scientific community is clear. Humans are the primary cause of most of the warming and ocean acidification.

We may have reached the point now where climate change has eclipsed the local impacts mentioned in the previous sentence as the greatest, most pervasive threat to coral reefs. See links above in paragraph (41).

There are multiple estimates of the biodiversity of coral reefs both from what is known and what is estimated to have not yet been discovered. In general, coral reefs contain about 25% of known marine species despite covering less than 1/10 of 1% of the ocean's area. This clearly makes them one of the most diverse ecosystems on earth, if not the most diverse.

Knowlton et al. 2010

Reaka-Kudla 1997

The combination of warming and acidification of the ocean is having tremendous consequences on organisms, ecosystems, ecosystem services, and human societies.

A recent summary of impacts of ocean acidification can be found in Turley and Gattuso 2012

A recent review of the combined impacts of ocean warming and acidification on ocean chemistry and physics can be found in Howes et al. 2015

A new review of the combined impacts of ocean warming and acidification on ocean chemistry, physics, ecosystems, and dependent human societies coming out shortly: Gattuso J.-P., et al., in press. Contrasting futures for ocean and society from different anthropogenic CO2 emissions scenarios. Science.

This has been especially true of the over-exploitation of reef fish.

Jackson et al. 2014

Coral reef decline has been well-documented and is accelerating due to the combination of local impacts and the global impacts of ocean warming and acidification due to anthropogenic increases in greenhouse gases.

Pandolfi et al. 2003 Knowlton 2001 Hughes et al. 2003