KCET Talks Ocean Acidification


C. Coimbra photo

Paul Bunje is senior scientist for energy and environmental programs at XPRIZE, an awards organization based in Southern California. What does Dr. Bunje do? In his own words: “I work to help solve environmental grand challenges by inspiring and facilitating innovation.” Trained as an evolutionary biologist, Dr. Bunje was founding director of the Los Angeles Regional Collaborative for Climate Action and Sustainability. At XPRIZE, Dr. Bunje is helping to lead the organization’s work on climate change. He talked to Maya Bon for Climate Resolve about ocean acidification and hypoxia, an area of focus for XPRIZE — and what we can do about these threats.

Can you give us a background on ocean acidification — what it is, how it’s caused, what it does to the ocean, and how it relate to climate change?

Paul Bunje: Ocean acidification is essentially the evil twin of climate change, as it is also the consequence of carbon dioxide emissions. About one quarter of the CO2 that we’ve emitted into the atmosphere is absorbed by the world’s oceans. When you put CO2 into water, it forms carbonic acid, which in turn drives down the pH of seawater. The challenge is that this is happening globally — as more CO2 goes into the atmosphere, more goes into the ocean…. [and] upsets the chemical balance of carbonate ions, carbonic acid, and CO2, which changes the chemistry that sea creatures work within.

One of the first identified impacts were the shells of creatures that make their shells out of calcium carbonate — corals, mollusks, bivalves, some important phytoplankton such as coccolithophore, which produces a significant amount of oxygen for the planet. When this chemistry balance is upset, it becomes more difficult to get the carbonate out of the water and these creatures cannot make their shells. In extreme cases, the shells dissolve. There are interesting cases of this occurring with sea butterflies, a microscopic snail, because of ocean acidification. You can actually see their microscopic shells dissolving in water.

Human actions have already increased carbon on the planet by about 40 percent. A quarter of that goes into the ocean. And the ocean has decreased by about .2 pH units, which may not sound like a lot. But, pH is a logarithmic scale like the Richter scale. So .2 pH is about 30% more acidic than it was before the Industrial Revolution.

All living creatures have an equilibrium of the pH in their blood. If your blood decreased by .2 PH, you would have a condition called acidosis, which is very often fatal. The same is happening with sea creatures. As it turns out, with more research that is being done, the impacts aren’t just corals, clams, and oysters, but other things that depend on an equilibrium in pH to do their basic living. Even fish, which don’t make anything out of calcium carbonate — whose bones are made of calcium phosphate like ours — have to exert more energy because the water is more acidic, in the same way that if our blood became more acidic it would take a lot of energy for us to survive.

So are all of these sea creatures going to die off?

PB: No, they’re not. I say that for a couple of reasons. One, the pH of the world’s oceans have been significantly lowered in the geologic past, in evolutionary history. So we know that some creatures can survive this. There has also been more and more research in finding species that are tolerant of variation in PH.

Yet there are some species probably will go extinct as a result of changes in ocean acidification, in particular those species that have evolved to be within a very stable pH zone. Others won’t.

Ultimately, what this means is that we are likely to see a significant amount of extinction and we are likely to see even more ecological change, meaning the diversity of species that happen to be in one particular place will change. We will see a real reshuffling of the way natural ecosytems work.

How quickly is the ocean acidifying? If we continue the way we’re living now, what types of impacts can we expect to see in our own lifetimes?

PB: It is occurring extremely quickly. What we have seen globally is that the rate of ocean acidification has been accelerating, which is very worrisome. Even more than that, the impacts seem to be cropping up more frequently and faster.

There are certain places with coral, a canary in the coal mine situation, that are experiencing a phenomenon known as coral bleaching. Corals can make their own energy through photosynthesis, harvesting sunlight using a symbiotic creature called a zooxanthellae. But they expel the zooxanthellae if they get stressed out. This stress is caused by warming temperatures and acidification. When that happens, the whole coral reef can die and turn into barren, white coral — essentially just rock. And when that happens the entire ecosystem disappears.

What is XPRIZE doing to address ocean acidification?

In 2013, XPRIZE launched the Wendy Schmidt Ocean Health XPRIZE, which was all about ocean acidification. As it turns out, we don’t know very much about our oceans. We don’t know which creatures live in it, we don’t know what the chemistry is like, we just haven’t studied it partly because it is so giant. And because ocean acidification was such a new concept, we candidly didn’t have enough data to even know where the impacts were happening in order to try and respond. For example, how quickly is it acidifying? Where is it exactly? How far does it extend? The ocean isn’t uniform. It’s not the same temperature everywhere. XPRIZE noticed that this came down to a very basic concern that you can’t solve what you can’t measure. We knew ocean acidification was happening because there were some researchers who would go out on a giant research ship and they would sample some water, put it in a bottle and ship it back to a lab and it was clear that it was more acidic. But that’s not a very easy way to understand what is happening off the coast of Los Angeles, for example.

It turns out it is really difficult to measure pH accurately and it’s even harder to do that in a place like the ocean where the conditions are difficult, where if you go too deep the pressure crushes the devices. It’s technologically difficult and nobody had done it, nobody had invested the money to do it. So XPRIZE launched a two million dollar competition, which is what XPRIZE does, for whoever could create a super accurate pH sensor and do it in a way that is usable and affordable.

We ran the competition for two years. Teams actually had to demonstrate their new technologies. We had twenty six entries into the competition with lots of different techniques that they were trying to measure PH. Like I said, it’s actually a very difficult thing to do scientifically. The final part of the competition was how to see in the middle of the Pacific Ocean these sensors go about 10,000 feet deep to see if they could measure all the way down there. One of the five finalists did not make it. It came back crushed.

But, what we ended up with was a number of new approaches and really phenomenal pH sensors that are now being deployed around the world. The winner was a team from Missoula, Montana, which is not known to have much of an ocean. And so now we have a whole lot of new technology out in the world that is starting to be deployed…. This is like putting carbon dioxide into the atmosphere but not measuring whether the temperature is changing or not. Maybe you’ve measured the temperature three or four times scattered around the world and thought, “Yeah, on average we know it’s changing but we have no idea what it’s like in LA.” That would be a comparison. We did not have the thermometers, basically, to measure ocean acidification. They just didn’t exist. And now we do, which is remarkable. It’s the first step.

Are there other initiatives here in California dealing with ocean acidification?

PB: There are. Actually, one of the real leaders on ocean acidification is led by a number of scientists in California, a very important scientific initiative called the California Current Acidification Network (C-CAN). It is led by Stephen B. Weisberg, the executive director of a research lab in Costa Mesa called the Southern California Coastal Water Research Project (SCCWRP). SCCWRP is an entity that is made up of the water agencies, primarily the wastewater and stormwater agencies of California. One of the things they have to test for is ocean pH because we dump a lot of stuff into the ocean here. They have done a lot of research on that.

There are two state-funded agencies, the California Ocean Protection Council and the California Coastal Commission, that have done a fair amount of work on ocean acidification along the coast of California, both research and attempts to understand how new approaches can help mitigate the effects of ocean acidification. For example, there’s work off Santa Barbara to plant seagrass because it seems to help stave off the effects of ocean acidification. People are also looking at kelp forests, which may do the same thing.

The same is true for some of the educational institutions including the Aquarium of the Pacific in Long Beach, the Monterey Bay Aquarium, the California Academy of Sciences in San Francisco who have all done important work to try to understand ocean acidification.

What can science, government, local groups, and individuals do to make a difference on ocean acidification?

PB: Ultimately, this is a CO2 problem. If you wanted to get down to the root cause, it would be to reduce CO2 emissions. Absolutely everything we do for climate change is good for ocean acidification as well. But, it’s more than that. We have to cease some of the so-called co-stressors, the other bad things we are doing to the ocean, because if you’re a sea creature hanging out on the bottom of the ocean and the chemistry starts changing around you, you can deal with that to a degree — the same way you and I can deal with being sick, for example. But, if a lot of things start hitting you at once then it’s really hard to deal with. Ocean acidification is happening. But if there is a place where the oxygen content is going down as well as the pH, those are two co-stressors that can kill almost any sea creature.

We want to reduce something like hypoxia, which happens when fertilizer runoff fertilizes algae, and then the process of decomposition consumes oxygen and drives down the oxygen levels in the water. Urban and agricultural areas need to ensure that their runoff is not filled with organic material like sewage. They need to ensure that it is purified. Basic pollution that goes into the water can be another stressor. The advice I typically give to a local manager, a local individual, is to reduce all of the other nasty things we do to the environment like waste and pollution as much as we possibly can. That can help maintain healthy ecosystems while we are trying to shutdown CO2 emissions globally.

What’s the timeline on further impacts? What’s the range of the potential impacts?

PB: Candidly, this is not well known. There is still not enough research on this.

There is a reasonable projection that by the end of the century there will be functionally no more coral reefs on the planet, which is horrifying. This doesn’t mean that all corals will go extinct. It does mean, however, that outside of a few protected areas that have special characteristics, coral reefs could completely die off. These are the rainforests of the sea — this is diversity on an unparallelled scale. The role that they play for humans is unbelievable because of the amount of fish that they produce or the fact that they prevent storm surge from things like hurricanes and cyclones. Once we start to lose that, we will be throwing things off-balance. We’ve seen in geologic history that as oceans become more acidic, global oxygen content in the air can go down, which can have devastating impacts to anything that breathes oxygen.

In terms of the time frame, the impact to sea creatures has been more rapid than we had thought and we learned that it impacts things like fish and lobsters that don’t use carbonate. So, we are just learning now how far-reaching these impacts could be. At the same time that we are doing this research, we are finding that natural systems have a built-in resiliency that we also don’t appreciate.

I think it’s our job as people, as stewards of the environment, to support that resiliency as much as possible, not to undermine it by putting other nasty things into the environment. Even if the pH changes — if creatures and ecosystems and habitats aren’t battered by all kinds of other stressors — they may be able to adapt and survive.

A genie grants you two wishes that will help fight climate change. What do you ask for? The third wish is for anything you want.

PB: First, I want carbon-free energy for everybody. It’s good for economic development and democracy.

Second, I would like massive protection of natural systems globally, but especially the ocean. I want to put a moratorium on overuse of any natural system on the planet, be that agricultural or fishing or habitat. The reason is that I know we need to adapt and I don’t want to lose species. Our natural systems are going to be an important part of our adaptation — building resilience into the system for humans, valuing things like mangroves and wetlands. I want to put a complete stop on any impacts to natural systems. Is that asking too much?

As for the third wish, if the sky’s the limit, I’d like to completely do away with the notion of sustainability because the world has adopted it as the only way to live. We have permanent, global, sustainable activity. Sustainable use of our resources, sustainable economic growth, sustainable lifestyle. And so we don’t say it anymore because it is just how things are.

—From KCET

Categories: Ocean acidification, Uncategorized

Tags: , , ,

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: