A science presenter, writer, speaker & former TV host; author of The Skeptic's Handbook (over 200,000 copies distributed & available in 15 languages).


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Scripps blockbuster: Ocean acidification happens all the time — naturally

There goes another scare campaign.

Until recently we had very little data about real time changes in ocean pH around the world. Finally autonomous sensors placed in a variety of ecosystems “from tropical to polar, open-ocean to coastal, kelp forest to coral reef” give us the information we needed.

It turns out that far from being a stable pH, spots all over the world are constantly changing. One spot in the ocean varied by an astonishing 1.4 pH units regularly. All our human emissions are projected by models to change the world’s oceans by about 0.3 pH units over the next 90 years, and that’s referred to as “catastrophic”, yet we now know that fish and some calcifying critters adapt naturally to changes far larger than that every year, sometimes in just a month, and in extreme cases, in just a day.

Data was collected by 15 individual SeaFET sensors in seven types of marine habitats.  Four sites were fairly stable (1, which includes the open ocean, and also sites 2,3,4) but most of the rest were highly variable (esp site 15 near Italy and 14 near Mexico) . On a monthly scale the pH varies by 0.024 to 1.430 [...]

The chemistry of ocean pH and “acidification”

The ocean acidification threat is a big can of worms. I asked Professor Brice Bosnich to help create a quick reference page on the chemistry and was pleased he could find the time to help. Here’s everything you wanted to know about the basics…

He explains what pH means, and points out that:

Ocean pH varies by 0.3 naturally. Claims of acidification since 1750 are based on dubious models and few observations.

There are reasons to assume that marine life will not be overly affected by an increase in ocean acidity due to atmospheric carbon dioxide:

Ocean life evolved and survived far higher levels of CO2 for millions of years in the past. Marine organisms actively create carbonate shells (using energy) which means crustacea, corals and molluscs aren’t automatically prey to pH changes in the same way that say a limestone rock would be. The world’s oceans may have warmed a mere 0.17C since 1955, hardly a significant threat to marine life.

We also find out that acidic water is added to the ocean from rainfall and floods (and he explains why raindrops will always be acidic).

There are more pressing threats. — Jo


Guest Post by Professor [...]

The debate continues: Dr Glikson v Joanne Nova

Dr Andrew Glikson (an Earth and paleoclimate scientist, at the Australian National University) contacted Quadrant offering to write about the evidence for man-made global warming. Quadrant approached me asking for my response. Dr Glikson replied to my reply, and I replied again to him (copied below). No money exchanged hands, but Dr Glikson is, I presume, writing in an employed capacity, while I write pro bono. Why is it that the unpaid self taught commentator needs to point out the evidence he doesn’t seem to be aware of? Why does a PhD need to be reminded of basic scientific principles (like, don’t argue from authority). Such is the vacuum of funding for other theories that a debate that ought to happen inside the university obviously hasn’t occurred. Such is the decrepit, anaemic state of university science that even a doctorate doesn’t guarantee a scientist can reason. Where is the rigor in the training, and the discipline in the analysis?

Credibility lies on evidence

by Joanne Nova

April 29, 2010

Reply to Andrew Glikson

Dr Andrew Glikson still misses the point, and backs his arguments with weak evidence and logical errors. Instead of empirical evidence, often [...]

No, Dr Glikson

Dr Andrew Glikson writes for Quadrant and I respond .

This is a copy. It begs the question. Dr Glikson, is an Earth and paleo-climate scientist at the Australian National University. He’s paid to give us both sides of the story.

No, Dr Glikson

by Joanne Nova

April 19, 2010

Dr Andrew Glikson says the right motherhood lines [see: Case for Climate Change]: he talks about empirical evidence, and wants evidence based policies. All this is good, yet he sidesteps the main point — what exactly is the evidence for the theory of man-made global warming? It’s the only point that matters, yet when he presents evidence it’s either not empirical, not up to date, or not relevant. Why?

By hitting all the right key phrases a reader might accidentally think that Glikson is presenting key evidence and good reasoning. Take this for example: Glikson fears we’re turning away from evidence-based policies. (Me too!) But to complete the sentence he lists all the committees who predict bad weather 90 years from now. It makes for good PR, but is not scientific evidence.

Committee reports count as “evidence” in a court of law, but in science, certificates, declarations, contracts, commission [...]