Climate Resolve Q&A: Paul Bunje

Paul Bunje of XPRIZE

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 its 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 weve 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, theyre not. I say that for a couple of reasons. One, the pH of the worlds 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 wont.

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 were 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 dont know very much about our oceans. We dont know which creatures live in it, we dont 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 didnt 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 isnt uniform. Its not the same temperature everywhere. XPRIZE noticed that this came down to a very basic concern that you cant solve what you cant 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 clea

LINK:	https://www.kcet.org/climate-change-la/climate-resolve-talk-with-a-sci...
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