Climate change: It’s all about the ocean
Geophysicist Marcia McNutt is president-elect of the National Academy of Sciences (NAS), editor-in-chief of the journal Science, and was the keynote speaker when the Aquarium honored Intel co-founder Gordon Moore on May 14 with its David Packard Award, recognizing Moore’s leadership in making the future of our planet surer and more sustainable. McNutt chaired the NAS climate intervention committee, was the former president and CEO of the Monterey Bay Aquarium Research Institute and a trustee of the Monterey Bay Aquarium. She also served as director of the United States Geological Survey and science adviser to the Secretary of the Interior. Here are her keynote remarks on climate change and ocean health:
I thought it fitting to paint a picture for you all of how far we have come in our understanding of the role of the ocean in anthropogenic climate change just in the 50 years or so since 1965 when Moore’s Law was first articulated. That year also coincides with the first warning by a group now known as the President’s Council of Advisors on Science and Technology about the potential for harm from continued release of CO2 into the atmosphere from the burning of fossil fuels.
It is staggering to consider that in 1965, observations of the ocean were limited to what could be obtained from a handful of anchored buoys and measurements along the ship tracks of expensive research vessels. The ships were limited by weather as to where and when they could collect information. In so many ways technology was not much advanced from the first oceanographic expedition, the HMS Challenger. Tools were still dredges and buckets and nets.
New ways to study the ocean
And then came visionaries such as David Packard, who said: “Send instruments to the ocean, not people. Bring back data, not samples.” He built institutions like MBARI to make that vision come true.
Fast forward to today. Unmanned platforms such as gliders, drifters, and autonomous underwater vehicles have replaced ships and buoys in providing high-resolution spatial and temporal coverage for physical and chemical changes in the ocean, such as temperature and salinity. We now know that each year the ocean absorbs an amount of heat roughly equivalent to one hundred times the average annual energy consumption of the United States. This heat that the ocean absorbs is about 90% of the heat building up from the release of excess greenhouse gases. If it were not for the oceans, the amount of global warming we would otherwise experience would be truly intolerable.
Progress in management and governance of the ocean is starting to see some returns in terms of proof of concepts, demonstration projects, and success stories. Back in 1965 there was little management of ocean fisheries beyond the race to catch the last fish, which unsurprisingly was the worst possible way to manage a fishery. This poor strategy led to widespread destruction of marine habitat and increased effort to catch fewer fish as we fished down the food chain.
Good science, good management
Today, thankfully, we are now actually applying some good science, from marine biology, economics, and behavioral science, to understand what promotes healthy stocks in the oceans and encourages the right response from fishermen. The Monterey Bay Aquarium has been a champion for decades in the movement to sustainable seafood.
California has been a leader in using science to establish marine protected areas and proving that they work. With the uncertainty of climate change, marine protected areas are an insurance policy to take the stress off the overexploited oceans. These protected areas are a necessary part of our management strategy for providing high-quality protein on a planet for which the productivity of the land surface is already maxed out.
I want to highlight especially the work of Jane Lubchenco, the world’s first Ambassador for the Oceans. Jane has traveled to places like China and Indonesia to encourage adoption of marine protected areas, individual transferable fishing quotas, and fishing cooperatives as tools to maintain healthy stocks for future years.
Global climate action
Finally, let me turn to governance. Back in 1965, when leaders were first learning of the risks of CO2 emissions, there was no discussion of global action to curb greenhouse gas emissions. Fast forward to today, when we recently have seen 195 nations come together on the Paris agreement to take action on climate change. Action on climate change falls into three categories: Mitigation, adaptation, and intervention.
Let’s start with mitigation. Mitigation, or reducing/eliminating the release of greenhouse gases, is generally the lowest risk approach to benefiting ourselves and the oceans. Californians are at the forefront of reducing their energy usage and greenhouse gas emissions. We can of course do more, but we are setting a great example for the rest of the nation.
I’ll turn next to adaptation. While humans may be able to adapt to some of the impacts of climate change, not so the oceans. Given the fact that we are highly dependent on the oceans for Earth’s habitability, for humans to rely on adaptation would be a short-sighted strategy.
Can we geoengineer a solution?
Finally, let’s discuss climate intervention, also commonly known as “geoengineering,” although the use of that term suggests a precision in the outcome that is illusory. One method of climate intervention is carbon capture. While some methods of carbon capture and storage are low risk, all approaches work slowly and are more expensive than simply not releasing the CO2 in the first place.
One method often discussed is ocean iron fertilization. Fifty percent of our oxygen comes from the ocean, from the absorption of CO2 by small plants that emit oxygen. But there is an excess of nutrients that would allow more CO2 to be drawn out of the atmosphere — if extra iron were added to the ocean to stimulate plant growth. Scientists have concerns about purposeful intervention in such a fundamental ocean process in this manner, and do not believe that this would be a safe method of climate control at this time.
Another method of climate intervention is modifying how much sunlight reaches Earth, for example, by injection of particles into the stratosphere to cool the planet by reflecting sunlight. This is what is naturally done by large volcanic eruptions. However, the process cannot be precisely controlled and has unknown effects on rainfall. It does not get to the source of the problem (excess CO2). While it might cool air temperatures quickly, it could not cool the oceans equally fast or impact ocean acidification. Injecting particles into the stratosphere is cheap, with respect to mitigation, adaptation, and carbon capture. Much needs to be done to warn others of these risks; otherwise, the low cost might carry the day.
When we tally up the pros and cons of these various responses to the risks of climate change, all of which can bring apparent relief for humans living on land, it is possible that adaptation, carbon capture through ocean iron fertilization, and stratospheric particle injection, either will not improve conditions for the ocean or could have deleterious effects. Mitigation and other forms of carbon capture will benefit the oceans. The voice of the oceans community needs to be at the decision table.
Above all else, science tells us that we cannot delay in deciding on a strategy for addressing climate change. Science does not dictate what approaches we should take, but does help clarify the tradeoffs: such as cost, speed, environmental and social impacts, to help society decide. My hope is that with leadership from great institutions like the Monterey Bay Aquarium, preferred approaches to tackling climate change are those that acknowledge the importance of the ocean to the welfare of every living being.
Featured image: Coral reef in the Northwest Hawaiian Islands. Courtesy NOAA.