Ocean acidification is once again in the news, with the Monaco Declaration. There is a lot of mystery and misunderstanding surrounding this topic. Below are a few points that I sent to a group, with claims and comments such as, “This sounds very alarming, so being diligent researchers we should of course check the facts. The ocean currently has a pH of 8.1, which is alkaline not acid. In order to become acid, it would have to drop below 7.0.”

1. “Acidification” refers to the lowering of pH, not whether the liquid is an acid or alkili. Acidity refers to the concentration of hydrogen ions in the liquid, of which pH is a logarithmic measure. So a decline in pH indicates an increase in the acidic properties of the liquid, regardless of what the actual pH number is. The ocean is a tremendous buffer, and pH should generally change only on geological timescales, as indeed we know it has. The fact that we have been able to measure a decrease in modern instrumental time is very disturbing.
2. The decrease is driven by the increased concentration of carbon dioxide in the atmosphere. When CO2, which is very soluble, dissolves in seawater, it undergoes a series of chemical dissociations, first to form carbonic acid, then free bicarbonate ions, and finally carbonate ions. As the ocean becomes more saturated with CO2, this equilibrium is being shifted so that solid carbonate salts become more soluble. The most common biologically produced carbonate is calcium carbonate, one form of which is used by corals for the construction of their skeletons. Therein lies the reasons to worry about the corals as atmospheric CO2 concentration rises.
3. There is a lot that we don’t know about the potential impact of this issue. It will definitely be detrimental for a lot of organisms, and not only because of the attack on their skeletons, but also because the increase in CO2 in the water often causes hypercapnia; think of this as strangulation underwater.
4. Some organisms might benefit, and there is some experimental evidence to support this now. However, before we celebrate this, I’ve noted that the reports of these organisms generally involve species that are currently minor ecological components. If they rise to more dominant ecological roles, we’ll see a shift in community/ecosystem compositions and functioning. Whether these changes will be bad, neutral, or beneficial to other species, as well as human economic dependencies, is a wide open question. Be concerned gentlemen.
5. To the coral aquarium enthusiast who claimed that his corals have never done better since adding CO2 to his water, I’ll point out simply that he is making it easier for the corals to mineralize their carbonate skeletons. His aquarium water is definitely not at a saturation point. If he’s interested, keep ramping up the CO2 concentration, and see what happens. Science at home.

I stumbled across a blog posting two days ago that was quite interesting: CO2, Temperatures, and Ice Ages. The analysis as presented contains some serious errors and misconceptions. I posted comments to that effect, but it seems that “skeptics” are intolerant of dissenting opinions, and my comments were never added to the blog. That’s too bad, and a bit funny since this is behaviour of which climate scientists are often accused (just read the voluminous comments on the posting; the ones which were published of course). That does not make for good science. Well, good thing I have my own blog. Maybe the authors of the other blog will stumble across it. So, take a look at the blog posting, and then read my (re-created) comments below…

The analysis are presented is flawed. The method of aggregating the data over several glacial-interglacial cycles, apparently by averaging estimated temperature values and carbon dioxide values invalidates the analysis. The cycles cannot be treated as independent replicates of a single process; they are serially correlated data. Moreover, the lag between temperature change and carbon dioxide concentrations is well known, and has absolutely nothing to do with carbon dioxides effectiveness as a greenhouse gas nor its role in the Pleistocene cycles. Our current regime of glacial-interglacial cycles was initiated approximately 2.4 million years ago, and temperature and carbon dioxide are reasonably well synchronized in the early cycles. Carbon dioxide however is intimately connected with the rest of the carbon cycles, and is affected noticeably by other processes such as fluctuating rates of carbonate deposition (which itself is intimately tied to global oceanic temperatures), carbon burial rates in the deep ocean, orogenic (mountain-building) processes, and erosion. To look at the data in the simplistic manner in which you did, and within such a narrow window, cannot be used to support a hypothesis of no role for carbon dioxide in global warming. And, very importantly, the implication that somehow prior interpretations of these data have been contrived to support arguments of current anthropogenic warming is nonsense. These data have been known and studied for decades (no, it did not all begin with a few ice cores), well before we became generally aware of the issue of modern climate crisis.

It came upon a midnight clear,
That glorious scent of coal,
With sooty air and greenhouse gas,
From fossil bodies so old.

Peace on the Earth and goodwill to all,
But please remember to care.
The World depends upon withdrawal
To give our future clean air.

Feeling a bit under the weather (pun intended!) these days, so this post will be short. I caught a report on the local news a few nights ago, warning of a cooling trend here in northern California. I was a bit concerned by the teaser, but the report turned out to be quite good. Yes, it seems that we are in a cooling trend, across a good chunk of the globe in fact. This is not news, however. The trend was noticed earlier this year, and results from a superimposition of oceanic cooling trends. Given the recent La Niña, we’ve had the coolest year this century! Add to that the expected northern hemisphere cooling over the next 15-20 years, and that’s all good news. It is very important to note, though, that these trends are unrelated to greenhouse gas warming (at least they do not interact directly), and that warming will continue. A very nice summary is given here by the BBC.

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Many years ago, I believe that I was 12 years old, I read a compilation of short science fiction stories entitled Universe 5, edited by Terry Carr. I was introduced to some of my favourite authors for the first time, including Ursula K. Le Guin and Fritz Leiber. Leiber’s entry was entitled “Mysterious Doings in the Metropolitan Museum”, and if I recall correctly, it featured an international convention of beetles at a “metropolitan” museum in New York City. I like to think that Mr. Leiber was in actuality referring to the American Museum of Natural History (that slightly larger but junior cousin of the California Academy of Sciences, ahem). Anyway, what really stuck in my mind about the story was that the cockroaches were excluded. So every morning, as the other beetles headed into the building for their meetings, circles of picketing roaches would march outside chanting “Blat, Blat, Blattidae”, Blattidae being one of the taxonomic families of cockroaches. It seems that the poor pests were offended by their continual exclusion from the esteemed college of that most diverse group of animals, the Coleoptera (beetles). What foresight on the part of Mr. Leiber, since we now know that the roaches are far more closely related to termites! But I digress. This is a blog about climate change after all!

Several months ago, one of my fellow scientists here at the Academy, Dave Kavanaugh came into my office with a disturbing but interesting story. Dave is one of the world’s foremost beetle experts and had spent some of this past summer revisiting sites in the Sierra Nevada where he had collected beetles more than twenty years ago. Many of these beetles are endemic (unique) to California, and live on or near the ice fields of our high alpine areas. Dave is interested in obtaining more specimens in order to conduct analyses of species DNA. Much to Dave’s dismay, many of the areas in which he collected successfully all those years ago are now devoid of snow and ice. The alpine air is warmer, the snow melts earlier, and the ice fields are shrinking. As for the beetles; Dave and his colleagues located some of the species at higher elevation, where the poor bugs are retreating in an effort to track a habitat suitable for their survival. Other species remain missing, and for all we know might now be extinct. The entire story is told far more eloquently here.

Why should we care about these ice beetles? Dave is hooked on beetles; he loves them. My fascination is a bit more abstract (see Le Guin’s “Schrodinger’s Cat” in Universe 5 for a glimpse into my own mind) and I want to know why we should care about the beetles. Why should we care about any species that is not of obvious benefit to our own species? I can’t give you a precise answer for the beetles, but an ecosystem is a complex network of dependencies and interactions. As we lose pieces, as we erode the system, we move closer and closer to points of unpleasant transitions. Need an explanatory analogy? Just think for a moment about a failed Dungeness crab harvest, the monetary cost of fighting insanely ferocious wildfires, and California’s ongoing water shortages. It’s all connected folks.

By the way, if you’d like to see some of these enigmatic beetles, stop by the Academy’s Altered States exhibit. You can watch them trudge about on a miniature ice field, and they’re awfully cute.

A recent visitor to the Academy brought this article from the National Post to my attention. After visiting our Altered State: California and Climate Change exhibit, reading the article raised some questions for our visitor. The article is very typical of a certain segment of the media that tends to politicize the science of climate change in a skeptical manner. I responded to both our visitor’s questions and the article, and I’ve posted my response below. I should point out that there is also certainly politicization of climate change science on the other side of the issue, and I will take this up in another posting.

Dear Visitor,

Thank you for your comments on the museum and the climate change exhibit.
And thank you for the link to Lorne Gunter’s article in the National Post. I
will indeed comment on it, but first let me address your question about solar
inactivity and cooler temperatures.

Solar activity is indeed one of the major influences on global temperature
and climate (see my blog entry here).
This activity tends to wax and wane cyclically on a couple of different
frequencies. The first is a seasonal one and is very easy to understand; it’s
based on the orientation of the Earth’s northern and southern hemispheres as
it orbits the sun. The second is a frequency that is roughly decadal, and is
more difficult to understand. It obviously has something to do with the
internal fluid mechanics of the sun, which in turn is influencing how much
heat is produced, but we don’t understand exactly why it cycles in such a
regular fashion.

Now, what does this have to do with ongoing global warming? Not much. The
influence of the sun has not varied very much for a very long time, and while
the amount of heat that it contributes does indeed vary over time, the
Earth’s warming trend is progressing independently of solar output. We have
considered solar activity very carefully, and it simply cannot explain the
observed warming. The fact that this keeps coming up again and again in
the “skeptics” media is, frankly, an annoying and dishonest misrepresentation
of science.

Mr Gunter’s article…I’ll pick this apart in a sequential manner. First,
notice that he refers to a string of news stories, not scientific articles.
He is simply wrong in implying that it is difficult to publish scientific
articles skeptical of global warming. A more accurate observation would be
that there are constantly articles questioning, checking, and re-checking
ideas and observations of the warming, and many of them run counter to our
current ideas. For example, it was recently demonstrated that the Greenland
ice sheet might not be melting as rapidly as previously thought (whew).
Another example would be the worry first raised a few years ago that deep
water circulation in the Atlantic was slowing down as the Arctic warmed. We
know now that the slowdown is part of a long-term cycle that is not being
driven by global warming (yay). And I could go on. What Mr. Gunter should
state is that the “string of news stories” really refers to the
self-perpetuating and unvetted output of an agenda-driven group of
journalists, himself included, and not the scientific literature.

The number of climate skeptics in the scientific community is not growing
at all. I believe that I am better informed of this than Mr. Gunter is. I do the science, I
read the journals, I write articles, I review articles, I go to conferences
and meet, chat and argue with colleagues. Mr Gunter does not.

The thrust of his article is summarized by the statement, “Because a funny
thing is happening to global temperatures — they’re going down, not up.”
Well now, doesn’t global temperature always go up and down on certain
timescales? Isn’t is cooler in winter and warmer in summer? What he is
referring to is the recent discovery of a multi-decade trend in North
Pacific/northern hemisphere temperatures, the Pacific Decadal Oscillation,
and we are indeed entering a cool phase. So yes, we can expect a slight
cooling over the next 20 years (that’s good news). However, and this is a
very important “however”, this cooling trend is imprinted on a longer-term
and constant rise in temperature, the global warming trend. So while the
cooling will occur, it will not be as significant as it would be in the
absence of human-caused, greenhouse gas-driven warming, nor will it be
permanent. As soon as the cycle begins to wane, the global warming trend,
which will have continued in the background, will make itself felt.

And who ever said that the Medieval Warm Period (MWP) “had to be made to
disappear”? This one made me laugh. The MWP is an absolutely fascinating
paleoeclimatic episode, and lots of scientists study its causes and effects
every day. Just look it up on Google Scholar. But it’s surrounded by
questions such as, how long did it last? How widespread was it? Did it occur
at the same time in all places? Whatever the answers, it seems that the MWP
was a real phenomenon, but that it was not a synchronous nor global event.
Note that even Mr. Gunter concedes, “…the period from 800 AD to 1300 AD was
unusually warm, particularly in Northern Europe.” Ah, if only the world
consisted only of Northern Europe, how much easier it would be to understand.

I’ll just skip ahead toward the end of the article where the NASA record is
discussed. Look at the graph. To draw the conclusion that global
temperatures “have given back” (whatever that is supposed to mean) most of
the warming that has occurred since 1980, from that graph, is a terrible
conclusion. I suppose that in the same way that some economists are
apparently inept at reading financial charts, there are apparently folks
applying the same ineptness to climate science.

In summary, let me just say that this non-scientific skepticism is
intellectually challenged. Scientists don’t “believe” in this or that
conclusion (see this blog post,
June 2007). We observe, we measure, we
hypothesize and test, and we reject our hypotheses or we fail to reject them.
It is what we are trained to do. It underlies the care with which we designed
the Academy’s climate change exhibit. If we did not discuss solar influence,
it is because it has no meaningful impact on the problem. Mr. Gunter and his
friends would do well to visit our exhibit with an open mind.

Again, thank you for visiting the Academy, and your kind words regarding our
efforts. And thank you for your questions. The Academy is here because we ask
questions.

Just when you think that messages and understanding are spreading, recent personal observations suggest otherwise. The data are increasing, we may already be experiencing impacts, and there is a growing awareness globally of the climate change problem. At the same time, however, I see both an increase in alarmism, and the perhaps predictable reactionary responses from disingenuous and ill-informed skeptics.

Geerat Vermeij and I recently published a short article in Science outlining our predictions of some of the effects that a future ice-free Arctic will have on the diversity of molluscs and other animals in the Arctic and North Atlantic oceans. The main predictions are that (1) species in the Bering and Chukchi seas (see figure) will migrate and invade the Arctic and North Atlantic, and that (2) as a consequence, diversity will increase in both those regions. We point out that although the invading species will most likely be competitively superior to their native counterparts, that we remain agnostic, or at least uncertain, of the ecological consequences of the invasion. (See, for example, this press release.) It was very interesting to see the story picked up by news agencies around the world. Nevertheless, it was also interesting, and somewhat amusing, to see negative comments posted on many blogs and newsites accusing us of all sorts of things. For example, several commentators wondered why we expect an increase in diversity to be “harmful”. My response is simple: We never said that it would be harmful, and my advice to those individuals is that they spend more time reading, and less time writing. One fellow, presumably from a state on the East Coast, said, “I’ll happily keep my SUV chugging if it means more shellfish on the table.” That’s funny! It really is. Some of you who know me well wouldn’t be surprised to hear me say something cynically funny if I were standing on the foredeck of the Titanic. I would, of course, also have realized the gravity of the situation (no pun intended), and the futility of my unrecorded comment.

Another example was brought to my attention recently in a comment to the blog regarding an article by Wall Street writer Bret Stephens. Mr. Stephens expounds, in this article, the usual agenda-driven skepticism that I’ve come to expect from short-sighted and frankly, unintelligent economists. He leaps upon a recent error in NASA’s reporting of the hottest year since instrument records have been kept, noting that it was 1934, not 1998. NASA made a boo-boo, but shame on Mr. Stephens. NASA is not responsible for keeping and reporting on our temperature records, NOAA is. And the far more accurate and reliable NOAA records remain unequivocal. Mr. Stephens also makes reference to recent reports that the planet is undergoing a cooling trend, and rather cynically (I could like this guy in another lifetime) questions the reliability of "apocalyptic" predictions. He is presumably referring to this article (apparently journalists, unlike scientists, are trustworthy enough to not have to cite their sources) which reports a cooling trend over the next 20 years. Indeed correct. Those scientists report on the increasing trend of a long-term oscillation in climate which will imprint a cooling signature onto anthropogenic warming for the next two decades, after which, it’ll be all warming again. This is not refutation folks, it’s a reprieve! Let’s put those 20 years to good use. My point is that skeptics such as Mr. Stephen’s would do well to separate science from their own professional concerns. I’m not even sure what those concerns are, since economic reports and forecasts seem to be so far removed from the current reality of negative experiences by many of the people enrolled in those economies.

Finally, I would like to suggest some caution to the "other" side of the debate. Alarmist statements without sound scientific underpinnings are not helpful. There are still a lot of open questions; they’re the ones that keep me optimistic. I’ve heard recent reference to the consequences of a 5 meter rise in sea level this century. Uhm yes, that would be horrific, and yes, it’s possible. But it is not, to the best of our current knowledge, probable. So let’s keep it honest. I don’t know if Pacific shellfish will devastate the North Atlantic. I am fairly certain that their bags are packed and they’re ready to go. Perhaps the guy with the chugging SUV will agree to send me his notes.

Many of you are now familiar with the major ongoing and predicted impacts of global warming: warmer air temperatures, changes in rain and snowfall, melting ice, rising sea levels, etc.. A more subtle change which is taking place, and one that escaped serious attention until a few years ago, is the acidity of the oceans.

Acidity is usually measured in pH units, a metric of the amount of free hydrogen ions in the liquid; those little buggers cause a liquid to be acidic. The acidity of seawater is determined almost entirely by the amount of carbon dioxide being dissolved into it from the atmosphere. The carbon dioxide gas dissolves, and undergoes a series of somewhat complicated transformations to eventually yield, among other things, carbonate ions. The world’s ocean is a vast volume of water, and it is normally buffered, meaning that it is very very difficult to alter its chemistry. The bright side of this is the fact that for a long time, the ocean has been absorbing a lot of carbon dioxide and heat from the atmosphere, and has therefore helped to slow down the impacts of our fossil fuel emissions. But, as I mentioned once before, there’s no free lunch, and it seems that all good things must come to an end. So too with the ocean’s gift. The ability of the ocean to absorb our bad stuff from the air is now declining rapidly; it’s filling up! One consequence is that the pH is declining noticeably (lower pH = more acidic).

So what does this all mean? Technically, one major consequence is the decline in available carbonate ions in seawater. As the pH falls, more carbon dioxide enters a bicarbonate ion phase. And again you ask, WHAT DOES THAT MEAN??! It means this. Calcium carbonate ("chalk") is the material used most commonly by marine organisms to build their skeletons. Corals, clams, snails, many algae, and so on, use it. As the amount of carbonate ions in seawater declines, it will become increasingly difficult for these organisms to build, and even maintain, their skeletons. The skeletons will begin to dissolve. This is a huge and looming disaster. Coral reefs are the most diverse marine ecosystems, and are of tremendous economic value in the tropics. Microscopic planktonic algae with carbonate skeletons are the major producers of food and oxygen in the oceans. Clams are one of the major groups of algal consumers in the oceans, providing a vital link between the producers and consumers. Tens of thousands of years of accumulated carbonate skeletons in the ocean could begin to dissolve and release their carbon dioxide back into the atmosphere. Ocean acidity could well be the elephant in the room.

Is it all doom and gloom? Maybe not. It is shocking, personally shocking, that we know so little about the effects of pH on marine organisms. But unlike temperature and salinity, pH does not vary very easily, and so we scientists perhaps paid less attention to it. Now, new studies are suggesting that it’s not all hopeless, and that the responses of organisms could be more varied than we realize. I’ll talk about that in my next post, and we’ll also chat about the last time that this happened, 55 million years ago.

I’m really welcoming myself back to the blog. For the past few months we have been moving the Academy to its new facility in Golden Gate Park, which has involved a lot of packing, moving, unpacking, and so on. Many of you know about moving, but in this case, moving includes the more than 22 million specimens in the natural history collections, as well as all the live animals, etc. We are also very busy getting the place ready for the grand re-opening to the public on September 27th!

But, I’m in the new facility and settled into my new digs. The blog is back, and I will post something new soon!

The new California Academy of Sciences is headed toward completion, and the process of preparing the new facility, readying the exhibits, and moving the more than 20 million specimens in our natural history collections is keeping many of us very busy. You can find out more about the happenings here, and view a very nice video here.

Nevertheless, science goes on. While discussing our planned exhibit on climate change with some external designers a couple of weeks ago, one of them commented on the topic of “uncertainty.” She said that we should avoid the word at all costs because the general public already does not trust scientists, and that everytime they hear that particular word, it reinforces the notion that we scientists don’t know what we’re talking about (”You can’t even predict the weather 12 days from now!”). Is this true? Please send comments if you have any! Anyway, nothing could be farther from the truth. Let me tell you, Uncertainty is part of the beauty of the Universe.

When we (scientists) use the term Uncertainty, we mean either unknown, not understood, or unknowable. Let me attempt to explain using climate change science as an example. There is uncertainty in our predictions of the future’s climate because there are unknown quantities in our reasoning. Some of these quantities include important feedbacks in climate change processes that we simply have not recognized. For example, who would have thought ten years ago that as ice sheets melt, that they would lubricate and accelerate their own slide towards the sea? Other important unknowns include all the human ones. How quickly will the developing world increase its carbon emissions over the next 100 years? How much international economic cooperation can we all count on? Then there is the “not understood.” There are processes and phenomena whose science still escape us. E.g. we know that clouds play a role in climate, but will it be an important role as the planet continues to heat up? Will it be a cooling role? I don’t know, though there are some very clever people out there trying to figure it out.

And then there is the unknowable. The notion that once we’ve understood the mechanisms at work in the world, and have measured the right things, that we will be able to predict the future the way that we predict the ticking of a clock, is a deep-rooted consequence of the Newtonian and Cartesian revolutions. It is a dangerous hubris. The Universe does not work that way. The revolution of quantum physics told us that the Universe is random at the smallest scales. More recently, areas such as Chaos Theory and Catastrophe Theory have revealed that even the most innocent looking phenomena, such as weather(!), can be full of surprises. Take a look at this little equation.
X(t+1) = rX(t)(1-X(t))

It simply tells us that the size of an animal’s population, X, at time t+1 is the product of the population’s size at time t, multiplied by the typical birthrate of the species (r). If r is 3 (members of the population have 3 offspring per breeding season in excess of deaths), then we see that one can predict population size well into the future; it’s a simple cycle (upper graph). Sir Isaac is happy. Now, however, let’s say that r is 3.6 (I know, you can’t have three and a bit kids, but just indulge me). At this value, and for most values beyond, population size is effectively unpredictable! There’s no randomness here folks. This is a deterministic but inherently unknowable system! Welcome to Chaos Theory. And welcome to weather prediction. In this case, Uncertainty is not the result of ignorance, it is part of the inherently unknowable Universe. The system cannot tell us where it’s headed if the system itself doesn’t know. Beautiful.

Btw, if any of you yougsters out there think that you can predict where the second population is headed, then you deserve a Fields Medal (let me know; I’ll nominate you). In the next posting we’ll get back to our modeling, touch on Catastrophe Theory, and chat about tipping points.

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