The ocean, our super hero ? Will those vast expanses of salty water, reaching down to lightless depths, be our planet’s saviour ? In an interview with Eos magazine, none other than our own Phil Renforth (yes, the same with whom we walked the rugged shores of Hawai’i), explains in a very accessible way how the ocean may assist us in combating effects of climate change. More specifically, Phil explains how raising the ocean’s alkalinity -it’s acid buffer capacity- may help to sequester more CO2 from the atmosphere. This is of course a shared research interest, as we collaborate on several fronts. The interview in Eos was done to accompany a scientific article Phil published in the journal Reviews of Geophysics, on the same subject. It would be silly to repeat what Phil has to say, so I invite you sit down and read it here. Enjoy !
Since 2007, the government of The Netherlands -a small but densely populated and strongly industrialised country in north-western Europe- by virtue of the Netherlands Environmental Assessment Agency (NEAA) or Planbureau voor de Leefomgeving (PBL) in Dutch, has been annually releasing data on global trends in CO2 emissions. In the beginning, the NEAA/PBL issued no actual report, but merely provided processed data on their website, accompanied by explanations and interpretations in Dutch. However, from 2008 onwards, the NEAA/PBL also offered supporting texts in English, while since 2010 it is possible to download full reports (in English) in PDF format. The newest report was just released, and reports on the data from the year 2016. Strikingly, it appears that global CO2 emissions have stabilised in the period 2015-2016. This may indicate that the so-called Peak Emissions (the point after which emissions start to drop) may be in sight.
Peak Emissions are a sign that the de-carbonisation of our society is actually happening. It means that the measures being taken by politicians, consumers and industry are actually taking effect. It does not mean that we are not emitting CO2 anymore, because we are. Some 35 billion tons all in all, over 2016 alone. The leading independent British daily newspaper The Guardian also picked up on the Dutch report and published a very accessible article on it. Peak Emissions are of course always determined in hindsight, but it certainly marks the possible beginning of a hopeful trend.
When a scale tips over too far towards one side, placing more weight on the other side will help to balance it out again. That is exactly what is meant by “Negative Emissions”. It means that to restore the global carbon balance, heavily perturbed by anthropogenic (carbon) emissions, humankind needs to create or enhance processes that draw down carbon [dioxide] from the atmosphere. The Earth itself is quite capable of balancing the fluxes of carbon into and down from the atmosphere, but does so at a slow, geological pace. Over time scales that run in the thousands, if not millions of years, more CO2 in the atmosphere will lead to more dissolution of rocks and minerals, thereby effectively consuming the CO2 and so working towards another balance. However, our Industrial Revolution is only 200 years old, and when it comes to carbon emissions, we have been industrious indeed. We have been emitting so much carbon in such a short period of time, that the Earth’s climate system is starting to react accordingly. Certainly, without any intervention, transport of CO2 to the deep oceans and more mineral dissolution would restore the carbon balance over the next centuries. But those are time scales, which rather exceed our normal frame of reference. Growth and development (of our society, our “ecosystem”, if you will) can prosper in more stable and predictable environments, whereas the climatic events to be expected -should the currents trends continue- will be a far cry from those stable conditions. It would thus be a proper expression of self-preservation to prevent such extreme and potentially dangerous climate change from happening, correct ?
If we would be so inclined to reverse the current trend, Mother Earth would need a little hand in re-setting the carbon balance. One way is obviously to turn down our emissions, by deep de-carbonisation of our economy, fast. However, the surplus carbon emissions already present in the atmosphere, will continue to cause climate change, until the balance is again set. But, as discussed above, that would exceed our normal working time frame, and leave us moreover feeling rather powerless in the face of imminent climate change. The other way is to increase the uptake of carbon from the atmosphere, and render the CO2 inert. While re-designing our economy, and creating incentives for industrial and societal collaboration for low- or no-carbon energy, we may simultaneously sequester as much CO2 as is needed. Negative emissions may thus buy us some time, and avert the point of no return. In fact, the latest Assessment Report (AR5) of the International Panel on Climate Change explicitly states (paragraph SPM.4.2.2, page 21 in the Summary for Policy Makers) the need for negative emissions to steer Earth’s climate back to a cooler state, with significantly less CO2 in its atmosphere. A recent peer-reviewed scientific publication in the journal Environmental Research Letters discusses the research efforts into negative emissions, concluding that a fast up-scaling is needed, which in turn depends on (greatly) increased research efforts.
Now, I am not an explicit advocate of one or the other climate change mitigation approach. But I am a fervent supporter of increased research efforts in that direction. If we do not start researching the consequences and potential pitfalls of climate engineering from this very moment onwards, we will never be able to expect our leaders to make well-informed and (most importantly) evidence-based decisions in the (near) future. In the UK, a 8.6 million-pound (9.8 million euro or $11.5 million USD) national research programme has been initiated, to investigate the “potential, as well as the political, social and environmental issues surrounding [the] deployment” of negative emissions technologies (NETs). We wish the researchers involved much success and good luck in their work, and are of course hoping to collaborate in the future.
Being home for only some weeks after our Hawai’ian adventure, I had to pack my bags again by the end of April. This time, I would travel entirely to the opposite end of the world, to the Tasmanian capital of Hobart (Australia). A colleague of mine, Dr. Andrew Lenton, of the Australian research institute CSIRO, had asked me to come and give a talk at the Fourth International Symposium on The Ocean in a High-CO2 World. Andrew works with large-scale biogeochemical models and because we knew each other from the climate mitigation research community, he told me this symposium would be the perfect stage to give a presentation on how olivine could be used against ocean acidification. I did not have to think too long before I accepted. Of course I wanted to be a week long among the greatest minds involved in researching the ocean’s future trends !
The entire conference was a big success. Apart from bringing together hundreds of scientists from all over the world, the symposium comprised a public townhall meeting, in which climate change and ocean acidification was explained to the general public. This was a very special experience, as the plenary hall filled up to the rim with “normal” people, who came to listen to scientists (also known as “not so normal people”), doing their best to deliver an interesting, yet accessible story. The turnout was enormous, and the questions were both plentiful and valid. I for one had the impression that people were not being told by your (stereo)typical scientist about climate change, but rather educated and informed on a voluntary basis, with genuine interest on both sides.
Walking among these researchers who had dedicated the last decade(s) of their careers to researching the state of the ocean and listening to the talks in the beginning of the week, the main message appeared grim: “We are facing unprecedented rates of warming and acidification, on top of the environmental pressures which have been going on for almost just as long: pollution and over-fishing.” However, as the week took shape, I managed to talk to many of these great researchers, hailing from many different sub-disciplines, becoming more and more confident that my presentation was going to fit in very nicely. It felt a bit odd, though. It was almost missionary, to bring this message of hope against Ocean Acidification. Sure, our experiments were done in the laboratory or in simplified systems, but still…the results were so consistent and the implications so compelling, that I felt very excited to present them. Finally…the hour had come to bring my work to the stage. On the one-but-last day of the conference, I stepped up unto the dais and gave my presentation, which was well received, I might add. Apart from some nice questions right after the presentation, I received many positive reactions. Also, people seemed very much surprised that there is a possibility for remediation at all, even though research into this subject is still very preliminary. To my surprise, the attention for my presentation even spread further than the conference. I was contacted by the science journal, New Scientist, to comment on the work we are doing with olivine against ocean acidification. And by the next week, the interview appeared in their new issue. Very nice to have the research receive such attention !
Now that the human influence on climate change has been firmly and unequivocally established in the newest IPCC Assessment Reports (ARs) that came out in 2014, the new director of the IPCC, dr. Hoesung Lee, has called for a stronger focus on climate solutions. Among these solutions is Enhanced Weathering of Olivine (EWO), which increases seawater pH, buffer capacity (alkalinity) and the CO2 uptake capacity of seawater. In this way, EWO would address the problem from two sides, mitigating Ocean Acidification and enhancing CO2 uptake.