Anthropogenically induced climate change has created a set of intriguing scientific
problems pertaining to the Seas and the Oceans on earth that can be monitored, analysed,
modelled and consequently understood at some level. The international research community
is deeply engaged in this endeavour as exemplified by the United Nations Decade of
Ocean Science for Sustainable Development (2021–2030). Even so, the types of problems
caused by human activity are inherently difficult to solve, if solvable at all, making
them equally difficult to approach and manage. Here we address these as ‘wicked problems’
(first discussed by Churchman 1967, and later defined and formalized regarding social
and natural sciences by Rittel and Webber 1973), posing challenges that currently
seem to surpass our ability to tackle them.
We see the Sea and the Oceans, but mainly from above—we see only the surface. A curved
and broken line that separates our world from the one below, from the life in and
of the Sea. Seen from ashore, its beauty and incessant perplexity is staggering—an
outlook which we increasingly seek refuge in, for recreation and for well-being (see
for instance Bowen et al. 2014).
Our land-based perspective is rewarding, but also limiting in its lack of three-dimensionality,
because the vastness of the Seas and the Oceans is so much more than the surface we
observe from a distance. It is what we cannot see which makes it so challenging to
understand. Water stretches across basins and beneath ice shelves, extending all the
way down to the abyssal depths. The Seas and Oceans cover over 70% of Earth’s surface
or 3.61 × 1014 km2 with a total mass of 1.4 × 1021 kg (Vallis 2011). It has a mean
depth of over 3.7 km, but even so all water on Earth can still be fitted in a sphere
of only 1400 km in diameter. Despite big numbers, clean water is a scarce commodity
that needs to be treated accordingly.
Ocean circulation and overturning, processes that involve wind-driven gyres, turbulent
diffusion and the sinking of surface water, are unevenly distributed globally. Gebbie
and Huybers (2011) estimate that 15% of the total ocean’s surface accounts for 85%
of the production of deep water. Despite the fact that this production is localized
to a few high latitude areas, it still enables continued water mass exchange between
the major interhemispheric basins.
This vital engine helps maintain a balance in earth’s climate by constantly moderating
it through uptake of heat and subsequent redistribution. On a human time scale, the
ocean engine is slow, given the volume in question, explaining why it can take up
to 1200–1500 years before submerged surface water in the Pacific Ocean reach the deepest
parts of the basin (Gebbie and Huybers 2012) or even longer before it resurfaces,
all depending on which ocean and water mass you examine (Wunsch and Heimbach 2008).
It is that sluggishness we have come to rest the fundaments of our fast-growing and
fast-living civilizations on because if the heat absorbed was released back from the
ocean on shorter time scales the impact of our expanding footprint would be immediately
evident. This is but one explanation for why we have taken the goods and services
provided by the Seas and Oceans for granted through the centuries, a type of behaviour
which has cemented a view that is hard to change. Numerous species have been decimated
until saved in the last hour like the Antarctic blue whale (Attard et al. 2016) or
the sea otter (Doroff et al. 2003). The list of threatened species is growing by the
day which in effect makes the global marine ecosystem less resilient to further change
(Levin and Lubchenco 2008).
The Ocean’s great storage capacity is something we have exploited to the full, and
have done for quite some time. For much too long we have believed in the concept that
“dilution is the solution to pollution”, and that the resources in the ocean, though
plentiful, would be endless. Surplus heat and CO2 are absorbed and funnelled to the
darkest nadirs, not to return to the surface before centuries have passed. The dire
side of the industrial revolution is conveniently hidden from our naked eye—if we
don’t see it, it’s easier to pretend it’s not there.
Even so, there is an increasing interest in the Oceans and the Seas, politically as
well as commercially. The paradox is inescapable, encapsulating our contorted modernity.
We undermine its functions at the same time as we expect ever more from it. Because
more food needs to be marine, and as we harvest down the food web, we inevitably make
recovery slower and more uncertain. Removing large predatory mesopelagic fish (i.e.
top predators) will alter the entire marine food web through trophic cascades, including
pelagic primary production, and might have unforeseen impacts on the general energy
flow of the entire marine ecosystem (van Denderen et al. 2017) and on their role in
capturing and exporting CO2 from the surface (Pauly et al. 1998; Daskalov et al. 2007).
Goods must be transported with ships (already 90% of global trade is by sea (Valentine
et al. 2013)), and atmospheric CO2 must be taken up, preferentially at the same pace
as now or faster. We have created a series of wicked problems, where the solutions
we propose oftentimes trigger new problems, or are merely covering up for old sins.
Despite the fact that sea level since 1993 has risen with 3.1 mm ± 1.4 mm y−1 (Dangendorf
et al. 2017) enhancing the risk of costal hazards, the coastal population of the planet
is on the rise. The fraction of humans now living less than 100 km from the coast
is at least 40% (Small and Nichollis 2003; http://www.un.org/esa/sustdev/natlinfo/indicators/methodology_sheets/oceans_seas_coasts/pop_coastal_areas.pdf),
and scenarios suggest that the trend is steepening (Neumann et al. 2015).
Our systematic exploitations have had, and continue to have severe effects on marine
and terrestrial ecosystems and on global climate itself. Some of these effects are
secondary, and we have barely seen the manifestation of them yet. Many of these problems
are wicked: they are moving targets that cannot be fully solved on human time scales,
and the success of whatever potential solutions we come up with are contingent on
how we frame them and what type of conflict of interest they embed in the first place.
On a geopolitical level the UN’s 17 Sustainable Development Goals are important, embodying
a moderate progress. They are written in the expectant language that international
politics demands. Goal #14, curiously dubbed ‘Life below water’, is all about the
Oceans and the Seas. Target 14.3 states that we need to « Minimize and address the
impacts of ocean acidification, including through enhanced scientific cooperation
at all levels. » (https://sustainabledevelopment.un.org/sdg14).
As opposed to many other consequences of industrial CO2 emissions, ocean acidification
is easier to grasp, but harder to reverse. More CO2 in the atmosphere due to combustion
of fossil fuels equates with more uptake of CO2 by the Oceans (e.g. Le Quéré et al.
2017). This gradually affects and ultimately lowers the pH value of the ocean, which
in turn contributes to ocean acidification. Observations confirm this (e.g. Sabine
et al. 2004). Observations also confirm that we keep on emitting CO2 at a surprisingly
high rate (as if the currency of scientific knowledge carries limited value for political
decision-making and subsequent societal action), and once the CO2 is absorbed by the
upper layer of the ocean it cannot easily be undone.
There is no backdoor out of this wicked problem, which we barely understand the range
or severity of. There is no silver bullet that will present a universal remedy for
the wickedness. Having a political target that depends upon ‘enhanced scientific cooperation
at all levels are’ is courteous to the science community, but will do little to ‘minimize
the impact’ or, more importantly, halt the current development on human time scales
unless other agents and processes put that insight to good use.
Acknowledging the problem, making it emblematic, but doing next to nothing is confusing
and demotivating. It paints a contradictory picture of reality that obfuscates a clear
understanding of what the crux of the problem is: our continued emissions of greenhouse
gases, our continued harvests and usage of ecosystem goods and services. And by doing
so, it becomes increasingly harder for the public to identify pathways to action that
at least resolve parts of the problem. We need an opening that shows the way forward,
and we need positive and sustainable examples based on scientific knowledge, implemented
at full scale rather than just demonstration-projects. An equivalent to The Montreal
Protocol on Substances that Deplete the Ozone Layer, only for the ocean, would serve
the purpose only if it were fast enough. Precisely how The Paris Agreement will be
played out in terms of reduced CO2 emissions remains to be seen, as is true for the
COP23 meeting in Bonn in November 2017, but atmospheric concentrations of CO2 will
continue to soar in decades to come and have in fact increased for 2017 as well (Le
Quéré et al. 2017).
Global sea level rise is another wicked problem. There are many others including deoxygenation
(Keeling et al. 2010) and plastic debris (Law 2017), which have little in common except
that they need to be addressed and managed. Reaching an international agreement on
marine plastic pollution could be the first important step towards a less polluted
scenario (Borelle et al. 2017). As for deoxygenation, it is barely mentioned in governmental
papers (Gallo et al. 2017). Other issues, like temperature and sea level, are possibly
better known outside the science community.
Consider the fact that since the mid-20th century over 90% of the excess heat in the
atmosphere due to greenhouse gases has been absorbed by the Oceans and during the
last century or so surface waters have warmed by 0.7° ± 0.08 °C (Jewett et al. 2017).
The phenomena mentioned here constitute problems that neither are easily addressed
nor solved. A task further complicated by the sheer number of stakeholders involved
because we all need to agree. The reality of rising sea level will not quietly go
away, not even when it finally stabilizes hundreds of years from now and our sustainable
targets will since long have elapsed and many coastal settlements have been abandoned.
Part of the surplus heat once absorbed at the ocean surface will by default resurface
and by then be someone else’s problem to handle.
The Oceans and the Seas are sometimes posed as a potential redeemer of the perilous
climate and environmental challenges we are currently facing only if we treat it right
(Cf. OECD 2016)—a message echoed by governments and international bodies. If that
truly is the case, then we need to start addressing it with the resources and attention
it necessitates. As of now, we still behave as if there is little urgency associated
with the wicked problems described here, but urgency can also result in ad hoc solutions
or statements with little or no positive impact.
We need serious and solid science-and-society interactions to grasp, comprehend, communicate
and ultimately perhaps try to tame some of the wickedness of the anthropogenized Ocean.
A step in the right direction would, according to Frame (2008), be to build “a constituency
that is willing to think beyond the next generation”. Such a view arguably permits
a wider perspective on several of the issues raised here and can perhaps replace the
sense of disbelief that haunts the ongoing debate about the ocean and by so doing
help create new pathways to action.