acidification | ConservationBytes.com

Citizens ask the expert in climate physics

24 11 2020

In the first of two consecutive interviews with climate-change experts, authors, editors and readers of the Spanish magazine Quercus have a chat with Ken Caldeira, a global-ecology researcher at the Carnegie Institution for Science (Washington, USA). His responses attest that the climate system is complex, and that we need to be practical in dealing with the planet’s ongoing climate emergency.

*PhD in atmospheric sciences and professor at* *Stanford University* (USA), Ken Caldeira has pioneered the study of ocean acidification and its impact on coral reefs (1) and geoengineering solutions to mitigate anthropogenic climate change by extracting carbon from the atmosphere and reflecting solar radiation (2, 3). He has also been part of the Intergovernmental Panel on Climate change (*IPCC) and assessed zero-emissions scenarios (4, 5). To the right, Ken manoeuvers a drone while collecting aerial data from the Great Barrier Reef in Australia (6). Source.*

SARS-Covid-19 is impacting the world. In our home country, Spain, scientists argue that (i) previous budget cuts in public health have weakened our capacity to tackle the pandemic (7), and (ii) the expert panels providing advice to our government should be independent of political agendas in their membership and decisions (8). Nevertheless, the Spanish national and regional governments’ data lack the periodicity, coherence, and detail to harness an effective medical response (9). Sometimes it feels as if politics partly operate by neglecting the science needed to tackle challenges such as the covid pandemic or climate change.

Having said that, even if a country has cultivated and invested in the best science possible, people have difficulties coming to terms with the idea that scientists work with probabilities of alternative scenarios. As much as there are different ways of managing a pandemic, scientists differ about how to mitigate the ecological, economic, and health impacts of a high-carbon society.

Thus, a more and more common approach is to make collective assessments (elicitations) by weighing different points of view across experts — for instance, to establish links between climate change and armed conflict (10) or to evaluate the role of nuclear energy as we transition to a low-carbon energy-production model (11). The overarching goal is to quantify consensus based on different (evidence-based) opinions.

The questions we here ask Ken Caldeira could well have different answers if asked of other experts. Still, as Ken points out, it is urgent that (of the many options available) we use the immense and certainty-proof knowledge we have already about climate change to take actions that work.

Interview done 23 January 2020

We italicise each question and the name of the person asking the question and cite one to three relevant publications per question. For expanding on Ken Caldeira’s views on climate change, see a sample of his public talks here and here and newspaper articles here and here.

Read the rest of this entry »

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Tags: climate change, climate disruption, climate models, climate physics, climatology, coral reefs, Emissions, Global warming, Gulf Stream, ice ages, interview, Ken Caldeira, nuclear energy, nuclear power, Stanford University
Categories : acidification, agriculture, anthropocene, biodiversity, carbon, climate change, climate shift, conservation, coral reefs, economics, environmental policy, Europe, extinction, ocean, research, science

Offshore Energy & Marine Spatial Planning

22 02 2018

I have the pleasure (and relief) of announcing a new book that’s nearly ready to buy, and I think many readers of CB.com might be interested in what it describes. I know it might be a bit premature to announce it, but given that we’ve just finished the last few details (e.g., and index) and the book is ready to pre-order online, I don’t think it’s too precocious to advertise now.

A little history is in order. The brilliant and hard-working Katherine Yates (now at the University of Salford in Manchester, UK) approached me back in 2014 to assist her with co-editing the volume that she wanted to propose for the Routledge Earthscan Ocean series. I admit that I reluctantly agreed at the time, knowing full well what was in store (anyone who has already edited a book will know what I mean). Being an active researcher in energy and biodiversity (perhaps not so much on the ‘planning’ side per se) certainly helped in my decision.

And yes, there were ups and downs, and sometimes it was a helluva lot of work, but Katherine certainly made my life easier, and she has finally driven the whole thing to completion. She deserves most of the credit.

Read the rest of this entry »

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Tags: acoustic, aquaculture, benthic communities, benthos, biodiversity, birds, buffer zones, cables, climate change, co-location, collision, conflict, earthquake, ecosystem services, energy, energy extraction, energy security, entanglement, epifauna, eutrophication, exclusion, exclusive economic zone, Fish, fisheries, fishing, food security, gas leak, impact, infauna, intertidal, invasive species, Law of the Sea, local knowledge, marine, marine mammals, marine spatial planning, mooring lines, noise, objective function, oil and gas, oil platforms, oil spill, OSPAR, partnerships, pile-driving, pipelines, planning, platforms, pollution, portfolio theory, production, productivity, Renewable energy, renewables, resilience, resuspension, sediments, social licence, spatial planning, stakeholder engagement, stakeholders, tidal energy, trade-offs, values, wave energy, wind farms
Categories : acidification, alien species, aquaculture, biodiversity, biowealth, birds, book, carbon, climate change, climate shift, community ecology, connectivity, conservation, development, economics, ecosystem function, ecosystem services, environmental economics, environmental policy, eutrophication, exploitation, fish, fisheries, food, habitat loss, harvest, invasive species, investment, management, marine protected area, modelling, monitoring, MPA, ocean, planning, pollution, prioritisation, research, seagrass, sustainability, toxicology, toxification

Noses baffled by ocean acidification

18 04 2017

Clown fish couple (Amphiprion percula) among the tentacles of anemone Heteractis magnifica in Kimbe Bay (Papua New Guinea) – courtesy of Mark McCormick. Clownfish protect anemones from predators and parasites in exchange of shelter and food. The fish tolerates the host’s venom because its skin is protected by a mucus layer some 2-3× thicker than phylogenetically related species (12); clownfish fabricate the mucus themselves and seem to obtain anemone antigens through a period of acclimation (13), but whether protection is acquired or innate is still debated. Clownfish are highly social bony fish, forming groups with one reproductive pair (up to 11 cm in length each) and several smaller, non-reproductive males. Reproduction is protandrous (also known as sequential hermaphroditism), so larvae are born male and, as soon as the reproductive female dies, her widower becomes female and the largest of the subsidiary males becomes the alpha male. The IUCN lists clownfish, generically named ‘anemone fish’, as threatened by the pet-trade industry and habitat degradation, although surprisingly, only 1 species has been assessed (A. sandaracinos). The clown anemone fish A. ocellaris is the species that inspired Nemo in the 2003 Academy-Award fiction movie – contrary to the logical expectation that the Oscars Red Carpet would generate support for conservation on behalf of Hollywood, of the 1568 species represented in the movie, only 16 % of those evaluated are threatened (14).

Smell is like noise, the more scents we breathe in one sniff, the more difficult it is to distinguish them to the point of olfactory saturation. Experimental work with clownfish reveals that the increase in dissolved carbon dioxide in seawater, mimicking ocean acidification, alters olfactory physiology, with potential cascading effects on the demography of species.

Places such as a restaurant, a hospital or a library have a characteristic bouquet, and we can guess the emotional state of other people by their scents. Smell is critical between predators and prey of many species because both have evolved to detect each other without the aid of vision. At sea, the smell of predators dissolves in water during detection, attack, capture, and ingestion of prey, and many fishes use this information to assess the risk of ending up crunched by enemy teeth (1, 2). But predator-prey interactions can be modified by changes in the chemical composition of seawater and are therefore highly sensitive to ongoing ocean acidification (see global measuring network here). Experts regard ocean acidification as the ‘other CO₂ problem’ of climate change (3) — just to emphasize that anthropogenic climate-change impacts terrestrial and aquatic ecosystems alike. Acidification occurs because the ocean absorbs CO₂ at a rate proportional with the concentration of this gas in the atmosphere and, once dissolved, CO₂ becomes carbonic acid (H₂CO₃), which in turn releases protons (H⁺) — in simple terms, pH is the concentration of protons (see video about ocean acidification): Read the rest of this entry »

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Tags: acidification, anemone, behavioural shift, Carbon dioxide, climate change, clown fish, Global warming, Nemo, odour, olfaction, physiology, scent, smell
Categories : acidification, behaviour, biodiversity, carbon, climate change, climate shift, conservation biology, decline, demography, development, ecology, extinction, fish, function, marine, ocean, predation, predator, research, threatened species, tropical

Get serious about divestment

21 11 2014

We are a sensitive and conflict-avoiding lot, aren’t we? Most scientists I know absolutely dread reprisals of any form, whether they are from a colleague commenting on their work, a sensationalism-seeking journalist posing nasty questions, or a half-wit troll commenting on a blog feed. For all our swagger and intellectual superiority complexes, most of us would rather lock ourselves in a room and do our work without anyone bothering us.

Fortunately for the taxpayer, we should not and cannot be this way. As I’ve stated before, we have at the very least a moral obligation to divulge our results to as many people as possible because for the most part, they pay us. If you work in any applied form of science (most of us do) – such as conservation, for example – then your moral obligation to make your work public extends to the entirety of humanity and the planet. That’s a staggering responsibility, and one of the reasons I’ve embraced many other forms of communication beyond the bog-standard scientific publication outlets.

There are many great examples of impressive science advocates out there – a few that come to mind are people like inter alia Lesley Hughes, James Hansen, Michael Mann, Paul Ehrlich, Bill Laurance, Barry Brook, Ove Hoegh-Guldberg, Tony Barnosky, Gretchen Daily, Emma Johnston, Stuart Pimm, and Hugh Possingham. There are even others willing to go to extraordinary lengths to make an evidence-based protest against society’s more inane actions. I’ve said it before, but it bears repeating – evidence-based advocacy can work.

To the topic at hand – I’ve been a little disappointed – to say the least – with the near-total silence emanating from my colleagues about the fossil-fuel divestment wave sweeping the world. While gaining traction worldwide, it wasn’t until The Australian National University took the bold move to divest (at least partially) from many of its fossil-fuel financial interests that it became a reality in Australia. Let’s face it – of all the types of institutions in our world, universities should be at the forefront of good, morally grounded and socially responsible investment strategies. They are, after all, meant to be filled with the most erudite, informed and cutting-edge people in the world, most of whom should have the best information at their fingertips regarding the precarious state of our environment. Read the rest of this entry »

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Tags: advocacy, climate change, divest, divesting, divestment, fossil fuels, fossil-fuel industry, plutocracy
Categories : acidification, Australia, biodiversity, carbon, climate change, conservation, economics, environmental policy, investment, science, science communication

Rise of the phycologists

22 09 2011

Dead man's fingers (Codium fragile) - © CJA Bradshaw

I’ve had an interesting week. First, it’s been about 6 years since I was last in Japan, and I love coming here; the food is exquisite, the people are fantastic (polite, happy, accommodating), everything works (trains, buses, etc.) and most importantly, it has an almost incredible proportion of its native forests intact.

But it wasn’t for forests that I travelled to Japan (nor the sumo currently showing on the guest-room telly where I’m staying – love the sumo): I was here for a calcareous macroalgae workshop.

What?

First, what are ‘macroalgae’, and why are some ‘calcareous’? And why should anyone in their right mind care?

Good questions. Answers: 1. Seaweeds; 2. Many incorporate calcium carbonate into their structures as added structural support; 3. Read on.

Now, I’m no phycologist (seaweed scientist), but I’m fascinated by this particular taxon. I’ve written a few posts about their vital ecological roles (see here and here), but let me regale you with some other important facts about these amazing species.

Some Japanese macroalgae - © CJA Bradshaw

There are about 12,000 known species of macroalgae described by phycologists, but as I’ve learnt this week, this is obviously a vast underestimate. For most taxa that people are investigating now using molecular techniques, the genetic diversity is so high and so geographically structured that there are obviously a huge number of ‘cryptic’ species within our current taxonomic divisions. This could mean that we’re out by up to a factor of 2 in the number of species in the world.

Another amazing fact – about 50 % of all known seaweed species are found in just two countries – Japan and Australia (hence the workshop between Japanese and Australian phycologists). Southern Australia in particular is an endemism hotspot.

Ok. Cool. So far so good. But so what? Read the rest of this entry »

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Tags: biodiversity, climate change, coral reef, diversity, extinction, Japan, macroalgae, marine, Seaweed
Categories : acidification, Asia, Australia, biodiversity, carbon, China, climate change, conference, conservation, deforestation, ecosystem services, endemism, fish, fisheries, habitat loss, harvest, hotspot, marine, research, southern Australia, The University of Adelaide

Scoping the future threats and solutions to biodiversity conservation

4 12 2009

Way back in 1989, Jared Diamond defined the ‘evil quartet’ of habitat destruction, over-exploitation, introduced species and extinction cascades as the principal drivers of modern extinctions. I think we could easily update this to the ‘evil quintet’ that includes climate change, and I would even go so far as to add extinction synergies as a the sixth member of the ‘evil sextet’.

But the future could hold quite a few more latent threats to biodiversity, and a corresponding number of potential solutions to its degradation. That’s why Bill Sutherland of Cambridge University recently got together with some other well-known scientists and technology leaders to do a ‘horizon scanning’ exercise to define what these threats and solutions might be in the immediate future. It’s an interesting, eclectic and somewhat enigmatic list, so I thought I’d summarise it here. The paper is entitled A horizon scan of global conservation issues for 2010 and was recently published online in Trends in Ecology and Evolution.

In no particular order or relative rank, Sutherland and colleagues list the following 15 ‘issues’ that I’ve broadly divided into ‘Emerging Threats’ and ‘Potential Solutions’:

Emerging Threats

Microplastic pollution – The massive increase in plastics found in the world’s waterways and oceans really doesn’t have much focus right now in conservation research, but it should. We really don’t know how much we’re potentially threatening species with this source of pollution.
Nanosilver in wastewater – The ubiquity of antimicrobial silver oxide or ions in products these days needs careful consideration for what the waste might be doing to our microbial communities that keep ecosystems alive and functioning.
Stratospheric aerosols – A simultaneous solution and threat. Creating what would in effect be an artificial global cooling by injecting particles like sulphate aerosols into the stratosphere might work to cool the planet down somewhat. However, it would not reduce carbon dioxide, ocean acidification or other greenhouse gas-related changes. This strikes me as a potential for serious mucking up of the global climate and only a band-aid solution to the real problem.
Deoxygenation of the oceans – Very scary. Ironically today I was listening to a talk by Martin Kennedy on the deep-time past of ocean hypoxia and he suggests we’re well on our way to a situation where our shelf waters could essentially become too anoxic for marine life to persist. It’s happened before, and rapid climate change makes the prospect plausible within less than a century. And you thought acidification was scary.
Changes in denitrifying bacteria – Just like we’re changing the carbon cycle, we’re buggering up the nitrogen cycle as well. Changing our water bodies to nitrogen sources rather than sinks could fundamentally change marine ecosystems for the worse.
High-latitude volcanism – One of these horrible positive feedback ideas. Reducing high-latitude ice cover exposes all these slumbering volcanoes that once ‘released’, start increasing atmospheric gas concentrations and contributing to faster ice melt and sea level rise.
Trans-Arctic dispersal and colonisation – Warming polar seas and less ice mean fewer barriers to species movements. Expect Arctic ecosystems to be a hotbed of invasion, regime shifts and community reshuffling as a result.
Invasive Indo-Pacific lionfish – Not one I would have focussed on, but interesting. These spiny, venomous fish like to eat a lot of other species, and so represent a potentially important invasive species in the marine realm.
REDD and non-forested ecosystems – Heralded as a great potential coup for forest preservation and climate change mitigation, focussing on maintaining forests for their carbon sequestration value might divert pressure toward non-forested habitats and ironically, threaten a whole new sphere of species.
International land acquisition – Global financial crises and dwindling food supplies mean that governments are acquiring more and more huge tracts of land for agricultural development. While this might solve some immediate issues, it could potentially threaten a lot more undeveloped land in the long run, putting even more pressure on habitats.

Potential Solutions

Synthetic meat – Ever thought about eating a sausage grown in a vat rather than cut from a dead pig? It could become the norm and a way of reducing the huge pressure on terrestrial and aquatic systems for the production of livestock and fish for human protein provision.
Artificial life – Both a risk and a potential solution. While I’ve commented before on the pointlessness of cloning technology for conservation, the ability to create genomes and reinvigorate species on the brink is an exciting prospect. It’s also frightening as hell because we don’t know how all these custom-made genomes might react and transform naturally evolved ones.
Biochar – Burn organic material (e.g., plant matter) in the absence of oxygen, you get biochar. This essentially sequesters a lot of carbon that can then be put underground. The upshot is that agricultural yields can also increase. Would there be a trade-off though between land available for biochar sequestration and natural habitats?
Mobile-sensing technology – Not so much a solution per se, but the rapid acceleration of remote technology will make our ability to measure and predict the subtleties of ecosystem and climate change much more precise. A lot more work and application required here.
Assisted colonisation – I’ve blogged about this before. With such rapid shifts in climate, we might be obliged to move species around so that they can keep up with rapidly changing conditions. Many pros and cons here, not least of which is exacerbating the invasive species problems around the globe.

Certainly some interesting ideas here and worth a thought or two. I wonder if the discipline of ‘conservation biology’ might even exist in 50-100 years – we might all end up being climate or agricultural engineers with a focus on biodiversity-friendly technology. Who knows?

CJA Bradshaw

Sutherland, W., Clout, M., Côté, I., Daszak, P., Depledge, M., Fellman, L., Fleishman, E., Garthwaite, R., Gibbons, D., & De Lurio, J. (2009). A horizon scan of global conservation issues for 2010 Trends in Ecology & Evolution DOI: 10.1016/j.tree.2009.10.003

Comments : 12 Comments »
Tags: biodiversity, conservation, horizon scanning, science
Categories : acidification, agriculture, alien species, aquaculture, Arctic, biocarbon, biodiversity, biosequestration, carbon, carbon trading, climate change, cloning, conservation, deforestation, environmental engineering, fish, fisheries, habitat loss, invasive species, marine, pollution, research, threatened species, trophic cascades

How to make an effective marine protected area

22 09 2009

Here’s a nice little review from the increasingly impressive Frontiers in Ecology and the Environment which seems to be showcasing a lot of good conservation research lately.

As we know, the world’s oceans are under huge threat, with predictions of 70 % loss of coral reefs by 2050, decline in kelp forests, loss of seagrasses, over-fishing, pollution and a rapidly warming and acidifying physical environment. Given all these stressors, it is absolutely imperative we spend a good deal of time thinking about the right way to impose restrictions on damage to marine areas – the simplest way to do this is via marine protected areas (MPA).

The science of MPA network design has matured over the last 10-20 years such that there is a decent body of literature now on what we need to do (now the policy makers just have to listen – some progress there too, but see also here). McLeod and colleagues in the latest issue of Frontiers in Ecology and the Environment have published a review outlining the best, at least for coral reefs, set of recommendations for MPA network design given available information (paper title: Designing marine protected area networks to address the impacts of climate change). Definitely one for the Potential list.

Here’s what they recommend:

Size

bigger is always better
minimum diameter of an MPA should be 10-20 km to ensure exchange of propagules among protected benthic populations

Shape

simple shapes best (squares, rectangles)
avoid convoluted shapes to minimise edge effects

Representation

protect at least 20-30 % of each habitat

Replication

protect at least 3 examples of each marine habitat

Spread

select MPA in a variety of temperature regimes to avoid risk of all protected reefs succumbing to future climate changes

Critical Areas

protect nursery areas, spawning aggregations, and areas of high species diversity
protect areas demonstrating natural resilience or rapid recovery from previous disturbances

Connectivity

measure connectivity between MPA to ensure replenishment
space maximum distance of 15-20 km apart
include whole ecological units
buffer core areas
protect adjacent areas such as outlying reefs, seagrass beds, mangroves

Ecosystem Function

maintain key functional groups of species (e.g., herbivorous fishes)

Ecosystem Management

embed MPA in broader management frameworks addressing other threats
address and rectify sources of pollution
monitor changes

Of course, this is just a quick-and-dirty list as presented here – I highly recommend reading the review for specifics.

CJA Bradshaw

McLeod, E., Salm, R., Green, A., & Almany, J. (2009). Designing marine protected area networks to address the impacts of climate change Frontiers in Ecology and the Environment, 7 (7), 362-370 DOI: 10.1890/070211

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Tags: biodiversity, conservation, marine protected area, MPA, reserve design, science
Categories : acidification, biodiversity, climate change, coasts, conservation, coral reefs, deforestation, ecosystem function, environmental policy, eutrophication, fish, fisheries, fragmentation, island biogeography, management, marine protected area, MPA, prioritisation, protected area

Realising you’re a drunk is only the first step

11 05 2009

I recently did an interview for the Reef Tank blog about my research, ConservationBytes.com and various opinions about marine conservation in general. I’ve been on about ‘awareness’ raising in biodiversity conservation over the last few weeks (e.g., see last post), saying that it’s really only the first step. To use an analogy, alcoholics must first recognise and accept that they are indeed drunks with a problem before than can take the (infamous AA) steps to resolve it. It’s not unlike biodiversity conservation – I think much of the world is aware that our forests are disappearing, species are going extinct, our oceans are becoming polluted and devoid of fish, our air and soils are degraded to the point where they threaten our very lives, and climate change has and will continue to exacerbate all of these problems for the next few centuries at least (and probably for much longer).

We’ve admitted we have a disease, now let’s do something about it.

Read the full interview here.

CJA Bradshaw

Comments : 2 Comments »
Tags: biodiversity, conservation, science
Categories : acidification, Australia, climate change, climate shift, conservation, coral reefs, ecosystem services, environmental policy, eutrophication, exploitation, extinction, fish, fisheries, habitat loss, harvest, illegal fishing, invasive species, marine, marine protected area, recovery, threatened species

Eastern Seaboard Climate Change Initiative

30 04 2009

I’ve just spent the last few days in Sydney attending a workshop on the Eastern Seaboard Climate Change Initiative which is trying to come to grips with assessing the rising impact of climate change in the marine environment (both from biodiversity and coastal geomorphology perspectives).

Often these sorts of get-togethers end up doing little more than identifying what we don’t know, but in this case, the ESCCI (love that acronym) participants identified some very good and necessary ways forward in terms of marine research. Being a biologist, and given this is a conservation blog, I’ll focus here on the biological aspects I found interesting.

The first part of the workshop was devoted to kelp. Kelp? Why is this important?

As it turns out, kelp forests (e.g., species such as Ecklonia, Macrocystis, Durvillaea and Phyllospora) are possibly THE most important habitat-forming group of species in temperate Australia (corals and calcareous macroalgae being more important in the tropics). Without kelp, there are a whole host of species (invertebrates and fish) that cannot persist. The Australian marine environment is worth something in the vicinity of $26.8 billion to our economy each year, so it’s pretty important we maintain our major habitats. Unfortunately, kelp is starting to disappear around the country, with southern contractions of Durvillaea, Ecklonia and Hormosira on the east coast linked to the increasing southward penetration of the East Australia Current (i.e., the big current that brings warm tropical water south from Queensland to NSW, Victoria and now, Tasmania). Pollution around the country at major urban centres is also causing the loss or degradation of Phyllospora and Ecklonia (e.g., see recent paper by Connell et al. in Marine Ecology Progress Series). There is even some evidence that disease causing bleaching in some species is exacerbated by rising temperatures.

Some of the key kelp research recommendations coming out of the workshop were:

Estimating the value of kelp to Australians (direct harvesting; fishing; diving)
Physical drivers of change: understanding how variation in the East Australian Current (temperature, nutrients) affects kelp distribution; understanding how urban and agricultural run-off (nutrients, pollutants, sedimentation) affects distribution and health; understanding how major storm events (e.g., East Coast Lows and El Niño-Southern Oscillation) affects long-term persistence
Monitoring: what is the distribution and physical limits of kelp species?; how do we detect declines in ‘health’?; what is the associated biodiversity in kelp forests?
Experimental: manipulations of temperature/nutrients/pathogens in the lab and in situ to determine sensitivities; sensitivity of different life stages; latitudinal transplants to determine localised adaption
Adaptation (management): reseeding; managing run-off; managing fisheries to maintain a good balance of grazers and predators; inform marine protected area zoning; understanding trophic cascades

The second part of the discussion centred on ocean acidification and increasing CO₂ content in the marine environment. As you might know, increasing atmospheric CO₂ is taken up partially by ocean water, which lowers the availability of carbonate and increases the concentration of hydrogen ions (thus lowering pH or ‘acidifying’). It’s a pretty worrying trend – we’ve seen a drop in pH already, with conservative predictions of another 0.3 pH drop by the end of this century (equating to a doubling of hydrogen ions in the water). What does all this mean for marine biodiversity? Well, many species will simply not be able to maintain carbonate shells (e.g., coccolithophore phytoplankton, corals, echinoderms, etc.), many will suffer reproductive failure through physiological stress and embryological malfunction, and still many more will be physiologically stressed via hypercapnia (overdose of CO₂, the waste product of animal respiration).

Many good studies have come out in the last few years demonstrating the sensitivity of certain species to reductions in pH (some simultaneous with increases in temperature), but some big gaps remain in our understanding of what higher CO₂ content in the marine environment will mean for biota. Some of the key research questions in this area identified were therefore:

What is the adaptation (evolutionary) potential of sensitive species? Will many (any) be able to evolve higher resistance quickly enough?
In situ experiments outside the lab that mimic pH and pCO₂ variation in space and time are needed to expose species to more realistic conditions.
What are the population consequences (e.g., change in extinction risk) of higher individual susceptibility?
Which species are most at risk, and what does this mean for ecosystem function (e.g., trophic cascades)?

As you can imagine, the conversation was complex, varied and stimulating. I thank the people at the Sydney Institute of Marine Science for hosting the fascinating discussion and I sincerely hope that even a fraction of the research identified gets realised. We need to know how our marine systems will respond – the possibilities are indeed frightening. Ignorance will leave us ill-prepared.

CJA Bradshaw