Most of the planet is covered by water – seas, oceans, rivers, springs, lakes and other aquifers make up a significant portion of the world as society knows it. Not enough, the seas have served, since the dawn of civilization, as countless possible sources of income. It is from this region that food, minerals and oil are extracted, as well as it brings the possibility of connecting distant countries through transport. Thus, when studies surrounding the importance of seas and oceans are carried out from the perspective of Economics, their essentiality gains a new parameter.

According to Lu Wenhai et al. (2019), the Blue Economy has two basic characteristics: it has a general economy attribute and is related to the sea. It is important to clarify that Economics is, as Thauan Santos teaches, a branch of social science that studies the chains of “production, distribution and consumption of wealth” (SANTOS, 2019). Due to this, when using such a lens to study the sea, it is clear that there is an evident focus on the exploration of its living and non-living resources, on the sustainable development of economic activities in such space, as well as on its use as a commercial route. Considering the sea's capacity to produce wealth, Santos argues that the “Economy of the Sea” is born interdisciplinary in its essence, given that it has a relationship with different areas of Social Sciences, such as Labor Economics, Finance and Public Policies, for example (SANTOS, 2019).

Due to such interdisciplinarity, studies focused on this area are still dispersed among authors, and there is a wide range of terms used that seek to conceptualize the subject, such as “Maritime Economy”, “Sea Economy”, “Ocean Economy”, “Blue Growth”, “Marine Economy”, “Coastal Economy” and the most used currently, “Blue Economy”. Although they all follow the same line of observing the ocean from an economic point of view and have no strict definition, these terms are not synonymous in their common use, which contributes to great conceptual confusion.

Maritime Economy typically refers to the shipping sector; Sea Economy encompasses the study of living and non-living marine resources in a sustainable way; the Ocean Economy comprises not only resources, but also activities carried out in the ocean, such as the offshore wind industry; the term Blue Growth is normally used to designate the sustainable growth of the maritime sector; the Marine Economy usually encompasses biological and ecological issues; and Coastal Economy is related to the coastal management of States and their sectoral problems and interests.

The most commonly used term “Blue Economy” is old – although it has gained prominence in academia and business circles in recent years. According to Santos (2022, p. 38), this expression was used for the first time in the academic setting in the 19th century, and its content was more focused on biological sciences. Currently, it can be seen as an “umbrella concept” and, for the aforementioned author, its scope is precisely what made its use so popular, considering that it allows it to cover all previously seen sectors and concepts (SANTOS, 2022, p. 50). Due to this, it can be said that Blue Economy studies the use of the seas and oceans, both from the point of view of living and non-living marine resources, as well as biology and the naval industry, in its various sectors, from the perspective of Economy and sustainable development.

For Lu Wenhai et al. (2019), the Blue Economy is a strategic structure; a policy; it is inserted inside the studies of the Green Economy; it is a sustainable form of Marine Economy; and is a marine-based new technology economy. Andrés M. Cisneros-Montemayor et al. (2021), in turn, understand that the Blue Economy allows the emergence of “socially equitable, environmentally sustainable and economically viable ocean industries”.

Due to globalization and growth in consumption by world society, studies related to the Blue Economy have grown in recent years, although, as mentioned, they are somewhat dispersed across different areas. Some coastal countries and islands have developed their own indices to measure both the economic potential of the sea and human dependence on it (SANTOS, 2019), such as the Maritime Potential Index (MPI) and the Ocean Index (OI). In Brazil, for instance, the concept of the Blue Amazon became very important for the country (as seen here), and recently, the Brazilian National Bank for Economic and Social Development – BNDES started to invest in the Marine Spatial Planning – PEM, a multisector policy strongly based on the Blue Economy studies.

Furthermore, although timidly, over the years, this concern for the economic potential of the seas, which began with interests from coastal countries, gained greater strength and caught the attention of international communities. Within the scope of the United Nations – UN, Santos (2019) analyzes two exponents who sought to provide some care for the sea from an economic perspective. The first of these occurred in 2000, through the creation of the Millennium Development Goals, whose objective 7b brought the perspective of ensuring environmental sustainability and protecting ecosystems, both terrestrial and marine.

Years later, there was the second exponent within the UN, namely the Sustainable Development Goals (SDG). The SDGs are development goals established within the scope of the 2030 Agenda for Sustainable Development, a plan adopted by the UN that aims to fulfill, over the period, several global development indicators, which cover the social, economic and environmental areas, among others. SDG No. 14 expressly addresses the need for sustainable management of the oceans, marine resources and their ecosystems.

This plan adopted by the UN is aligned with the Ocean Decade (2021-2030), which is an initiative approved during the 72nd General Assembly of the United Nations that aims to promote the development of scientific studies in various areas that are related to the ocean. The project seeks international cooperation between nations, in order to create ideas, solutions and partnerships and thus build a basis for implementing the 2030 Agenda. This stance adopted by the international community demonstrates the importance that marine resources and the sustainable use of the oceans represent from the perspective of several areas, and Economics is one of them.

Thus, in view of climate change and its harmful effects on the ocean (as seen here), as well as the current and growing problems that draw attention to the marine environment (overfishing, plastic pollution, among others), the strength demonstrated by the Blue Economy is positive for the sustainable development of the oceans. The sea provides diverse forms of resources to human beings, whether through food, transport or the energy generation sector, and it is essential that this potential is explored in a sustainable and conscious way by industries.