TOMORROWS

16 OCEANS,
THE NEW
HUMAN
FRONTIER

With a population of more than 7 billion people, Earth already presents worrying signs of overexploitation of its natural resources, which are now considered on the verge of exhaustion. Humanity is looking for new sources of resources and it can “stretch” a little more its maintenance on the planet by using technology and creativity for its benefit, and unfortunately also by taking advantage of the social inequality factor.

In this context, given the limits of natural resources, the future imposes the imperative need for new options for sources of resources. On this horizon, the seas are emerging as a source for human maintenance, as they are much more available and reachable than other planets, which need to be explored.

To get an idea of the extent to which oceans constitute a veritable Universe to be harnessed, one only needs to consider that people have already traveled to the Moon more times than they have visited ocean depths greater than 3,000 meters. More than 80% of the Pacific Ocean’s area is deeper than this, and we have reached such places very few times. It is estimated that we have yet to discover more than 750,000 marine species – in other words, three times as many as we know of currently.

Since we do not yet know the oceans’ potential, the maintenance of important environmental services supplied by the sea – such as oxygen production, carbon sequestration, food production, and heat distribution around the planet – depends on how we will interact with them. So far, we are still “in the red”, as we have produced significant negative impacts.

The next 50 years seem crucial for humans to learn to take friendlier paths in their relations with the oceans. Humanity must not miss the great chance it has now to develop new technologies and to avoid making the same mistakes in the seas that it has committed on the continents. The future use of marine resources with social justice therefore depends on the human capacity to know how to respect their limits of use and cycling of natural elements.[1]

It is already possible to note many changes under way in the oceans: rising sea levels and water temperatures, acidification and pollution of coastal waters. These gradual transformations may not affect us at first, but we should take into account that sudden changes may arise from them. The increased frequency and intensity of storm surges, cyclones, intense rain, violent waves and dead zones in coastal environments demonstrates the ocean’s potential aggressiveness, hence our concern regarding its degradation. Accordingly, the coming decades may be seen as a decisive period for the rectification of the environmental liability we have accumulated in the last century (including global warming, overfishing, and the gradual and growing buildup of discharged pollutants, among many other elements).

A better understanding of the oceans’ natural cycles would be fundamental to promote a change in attitude regarding our relationship with the sea. In addition to losses – which almost always happen – these one-off and extreme phenomena may affect people’s safety and their future relationship with the ocean. By making more research efforts, for example, it would be possible to act in this direction, correcting the mistakes of the past and materializing the implementation of new technologies.

One of the first steps toward a change in attitude would be for us to perceive which ocean reactions are evidence of damage and therefore deserving of more attention. One important observation – posing a growing threat of collapse to coastal buildings, ports and even offshore oil platforms – is the fact that our coastline is being significantly altered, with silting or erosion processes observed in many places. The risk of coastal plain flooding, caused by sudden and one-off fluctuations in the sea level due to violent waves and storm surges, is now also a reality.

To propose a new attitude, technical construction and safety standards need to be updated in accordance with the new climatic and oceanographic conditions that are forming. In the medium term, we should also pay attention to the aggressiveness of sea spray, which is causing coastal buildings to deteriorate more quickly.

Let us look, for example, at urban beaches, which are environments made fragile by human occupation as well as climatic and oceanographic fluctuations. The coastal areas of Rio de Janeiro have experienced a gradual increase in the impacts of significant violent waves.2Over the course of 21 years (from 1991 to 2011), we have seen a substantial rise in the average annual number of periods of violent waves in three-year periods. Likewise, we have recorded an increase in the number of days with significant violent waves, indicating growing pressure on these beaches.

In terms of diversity of impacts, we have also perceived saturation over the years, with stabilization at the maximum rate in recent years (from 2006 to 2011). Due to the observed impacts, we recommend preventive procedures to prevent the loss of beach resilience, such as the use of structures to protect against violent waves. Ecological restoration, involving beach nourishment and/or regeneration of vegetation, is one of the recommended strategies.

In Brazil, areas of the coast made fragile by dense human settlement in the South (Santa Catarina), Southeast (Rio de Janeiro) and Northeast (Pernambuco) will suffer significant impacts. [3] Such coastal areas must therefore be adapted to resist these new climatic and oceanographic conditions. The main impacts related to coastal erosion are as follows: reduction in beach width; retreat of coastline; disappearance of post-beach zone; loss of natural habitats, such as beaches, dunes, mangroves and restinga (sandy coastal vegetation); and increased frequency and magnitude of coastal flooding caused by violent waves or very high tide events. [4]

Beaches are mainly used for recreation and coastal protection. [5] In the latter case, it is necessary to establish minimum beach widths to promote greater resistance to the erosive action of waves and prevent them from getting close to urban infrastructure (sidewalks, lifeguard posts, kiosks and coastal avenues). Recommended preventive (anticipatory) measures include artificial beach nourishment and the restoration of sandy vegetation. Macumba and Arpoador, in Rio de Janeiro, are examples of beaches in Rio de Janeiro that have become squeezed between human occupation and the advance of the sea. Thus, one can perceive the importance of maintaining beaches as an element of coastline adaptation in the face of climate change.

The coastal areas of Rio de Janeiro have experienced a gradual increase in the impacts of significant violent waves. Over the course of 21 years (from 1991 to 2011), we have seen a substantial rise in the average annual number of periods of violent waves in three-year periods. Likewise, we have recorded an increase in the number of days with significant violent waves, indicating growing pressure on urban beaches.

One of the main parameters taken into consideration for beaches as a protective element is their width. [6] In the case of urban beaches, such as along Rio de Janeiro’s coast, it is fundamental to formulate public land use policies, as well as long-term interventions to maintain these coastal systems.

Another important element is water use and consumption. Human beings currently use the oceans as an area for discharging anthropogenic effluents, extracting petroleum and food sources, and transportation. New uses, such as energy production, mining and pharmaceuticals, are possibilities to be considered. In addition, the salinization of groundwater in coastal zones – an occurrence that may arise from climate imbalance – would impede the harnessing of underground springs, worsening the shortage of drinking water.

The projected oceanographic scenario challenges humanity to invest financially and politically in cutting-edge research and also the planning and development of strategies to enhance the use of natural resources. To stop viewing the oceans as places to dump waste, it would be interesting to develop their other beneficial uses for them and not only prepare to occupy them, but also research new ways of doing so sustainably.

A good way to increase the resilience of the cities of the future and the natural environment around them would be to develop coastal management strategies aimed at better land use, respecting coastal fragilities and harnessing their potentialities with wisdom. Another fundamental strategy is to monitor oceans’ evolution and behavior to better understand the energy exchanges between the planet’s different spheres: the hydrosphere (oceans), lithosphere (continent), and atmosphere (air).

We now have some knowledge of the planet’s changes arising from human action. It is up to us to seek the necessary means to reverse this degenerative process in the coming decades. To this end, we need to assume a questioning, reflective and purposeful perspective. Transforming all this data into information that is useful and understandable to society, encouraging people’s participation and responsibility in the process, is extremely relevant, as it will favor a change in attitude toward nature.

Who knows, perhaps the oceans are giving us the opportunity to do things right, based on the mistakes we have made on the land, and this might be one of the best options for us. Humanity may live on the planet in a sustainable way if we respect nature and consider it as a partner in our journey. After all, it is not about saving the planet; it is we who need to save ourselves from what we have done so far.

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