by Anthony Watts, August 17, 2018 in WUWT
From the “science eventually self-corrects” department, new science showing coral bleaching of the Great Barrier Reef is a centuries-old problem, well before “climate change” became a buzzword and rising CO2 levels were blamed.
Marc Hendrickx writes:
New paper shows coral bleaching in GBR extending back 400+ years.
by Anthony Watts, August 4, 2018 in WUWT
MIAMI—New research shows that not all corals respond the same to changes in climate. The University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science-led study looked at the sensitivity of two types of corals found in Florida and the Caribbean and found that one of them—mountainous star coral—possesses an adaptation that allows it to survive under high temperatures and acidity conditions.
“Stressful periods of high temperature and increasingly acidic conditions are becoming more frequent and longer lasting in Florida waters,” said Chris Langdon, marine biology and ecology professor and lead author on the new study. “However, we found that not all coral species are equally sensitive to climate change and there’s hope that some species that seemed doomed may yet develop adaptations that will allow them to survive as well.”
See also (in French) here and here
by JoNova, June 12, 2018 inJoNovaBlog
After half a billion million years of climate change, I’m shocked, shocked I tell you, that life on Earth (and specifically corals) have so many ways to cope with the climate changing. After all, it’s natural (if you are trained by Greenpeace) to assume that corals can only survive in a world with one constant stable temperature just like they never had.
One more tool in the coral-reef-workshop
Corals don’t just have a tool-box, they have a Home Depot Warehouse. h/t to GWPF
by Ross C.L. et al., 2017, June 10, 2018 in CO2Science
The global increase in the atmosphere’s CO2 content has been hypothesized to possess the potential to harm coral reefs directly. By inducing changes in ocean water chemistry that can lead to reductions in the calcium carbonate saturation state of seawater (Ω), it has been predicted that elevated levels of atmospheric CO2 may reduce rates of coral calcification, possibly leading to slower-growing — and, therefore, weaker — coral skeletons, and in some cases even death.
As we have previously pointed out on our website, however (see The End of the Ocean Acidification Scare for Corals and A Coral’s Biological Control of its Calcifying Medium to Favor Skeletal Growth), such projections often fail to account for the fact that coral calcification is a biologically mediated process, and that out in the real world, living organisms tend to find ways to meet and overcome the many challenges they face; and coral calcification in response to ocean acidification is no exception.
See also in French
by Prof. Dr. P. Berth, 5 juin 2018, in ScienceClimatEnergie.be
Voici quelques réflexions sur la théorie de l’acidification des océans. Selon cette théorie, le pH des océans diminuerait inlassablement, en raison du CO2 qui ne cesse de s’accumuler dans l’atmosphère.
• Les mesures directes de pH sont récentes et nous n’avons aucun recul. Selon les médias et les ONG écologistes, qui se basent sur le GIEC et sur certaines publications (e.g., Caldeira & Wickett 2003), le pH des océans aurait été de 8.25 en 1750. Cependant, il faut savoir que personne n’a jamais mesuré le pH des océans en 1750, puisque le concept de pH n’a été inventé qu’en 1909 (par le danois Søren P.L. Sørensen), et que les premiers appareils fiables pour mesurer le pH ne sont apparus qu’en 1924… Nous ne sommes donc pas certains de cette valeur de 8.25 pour 1750… La valeur de 8.25 est donc obtenue par des mesures indirectes et n’est donc pas certaine.
• A l’heure d’aujourd’hui, tous les pH sont possibles. Lorsqu’on dit que les océans actuels sont à un pH de 8.1, de quel océan parle-t-on? S’agit-il du pH moyen global? Si c’est de cela qu’on parle, quelle est l’incertitude sur la mesure? (i.e., l’écart-type?). Ceci n’est jamais indiqué. Il faut savoir que si l’on prend un jour de la semaine, tous les pH sont possibles dans les océans, comme l’illustre très bien la figure suivante.
by David Middleton, June 5, 2018 in WUWT
The Fable of Chicken Little of the Sea
Guest essay by David Middleton,
When if comes to debunking Gorebal Warming, Chicken Little of the Sea (“ocean acidification”) and other Warmunist myths, my favorite starting points are my old college textbooks.
Way back in the Pleistocene (spring semester 1979) in Marine Science I, our professor, Robert Radulski, assigned us The Oceans by Sverdrup (yes, that Sverdrup), Johnson and Fleming. Even though it was published in 1942, it was (and may still be) considered the definitive oceanography textbook. I looked up “ocean acidification” in the index… It wasn’t there.
The notion that CO2 partial pressure influences the pH of seawater isn’t a new concept, *surely* ocean acidification must have been mentioned in at least one of my college textbooks.
by S. Xu et al., December 2017, in AGU1000Biogeosciences
Coral bleaching is becoming a serious issue for coral reefs under the stress of global warming. However, whether it has occurred in the past in times of thermal stress remains unclear. Moreover, an understanding of historic coral bleaching events would greatly improve our insight into the adaptive capabilities of corals under such stresses. It is known that Porites corals, a massive coral, have relatively high levels of symbiotic zooxanthellae and a strong thermal tolerance when compared with most other corals (and particularly branched corals). Thus, growth hiatuses and/or mortality surfaces of fossil Porites may be used to indicate past ecological or environmental stress events, such as severe bleaching. In this study, monthly geochemical and isotopic environmental proxies of four fossil Porites corals with well‐preserved growth hiatuses and mortality surfaces (aged 3,800–4,200 years before 2013 A.D.), collected from Wenchang fringing reef, Hainan Island, Northern South China Sea were analyzed. Specifically, the Sr/Ca, δ18O, and δ13C were measured with a monthly resolution for each sample.
by Kate Wheeling, April 19, 2018 in PacificStandard
Coral reefs are facing no shortage of threats including ocean acidification, overfishing, plastic pollution, and rising temperatures. Sea surface temperatures have been climbing on average for over a century, and ocean heat waves—which can trigger coral bleaching events—are becoming more common and severe. Scientists have long worried that as coral-killing spikes in temperature become more frequent, corals won’t have enough time to recover between bleaching events and will ultimately go extinct. But a new paper, published today in PLoS Genetics, suggests that corals might be able to adapt to another century of warming.
by Donald et al. 2017, in CO2Science from Géochim.Cosmochim.Acta
The influence of pHsw on both pHcf and the calcification rate of Neogoniolithon is plotted in Figure 1 below. As indicated there, this coralline algal species is able to elevate its pHcf so as to increase its rate of calcification under moderate levels of ocean acidification (pHsw of 7.91 and 8.05), which increase the authors say is “most likely due to CO2-fertilization of [algal] photosynthesis” that is limited in Neogoniolithon at these lower pCO2 conditions. (….)
by Matt Ridley, December 12, 2017
A 2010 analysis of 372 studies of 44 different marine species found that the world’s marine fauna is “more resistant to ocean acidification than suggested by pessimistic predictions” and that it “may not be the widespread problem conjured into the 21st century”
by Andy May, October 4, 2017 in WUWT
Georgiou, et al. 2015 have reported that coral reefs in the Australian Great Barrier Reef, near Heron Island, are insensitive to ocean pH changes. The location of Heron Island, about 257 miles (414 km) north of Brisbane, Queensland, Australia, is shown in figure 1 using Google maps
by David Middleton, July 17, 2017 in WUWT
The Tethys Sea couldn’t have been a better place for petroleum source rock deposition even if it had been designed for such a purpose. The “Tethyan realm” encompassed much of the Jurassic and Cretaceous periods…
See also here and also here
by S.D. Connell et al., 2017 in Current Biology (in CO2 Science)
The increasing absorption of CO2 and associated decline in seawater pH values is thought to pose direct harm to marine life in the decades and centuries to come by affecting rates of survival, calcification, growth, development and/or reproduction. However, as ever more pertinent evidence accumulates, a much more optimistic viewpoint is emerging.
by Mote Marine Laboratory, June 5, 2017 in ScienceDaily
A controlled lab study led by Mote Marine Laboratory and published June 1 in the peer-reviewed journal PLOS ONE revealed that black band disease was less deadly to mountainous star coral (Orbicella faveolata) as water acidified, or decreased in pH.
by N.R. Evensen and P.J. Edmunds, 2017, J. Exp. Biology
Regardless of the actual mechanism responsible for the densely aggregated corals to maintain calcification rates in the face of ocean acidification, the study of Evensen and Edmunds, in their words, offers “a compelling case for differential densities of branching coral colonies (i.e. aggregation types) mediating the sensitivity of coral communities in at least some habitats” and it further supports “recent indications that neighboring organisms, such as conspecific coral colonies in the present example, can create small-scale refugia from the negative effects of ocean acidification” And that is more good news for those concerned about the future health of these important marine ecosystems.