Introduction
The South China Sea (SCS) and the Southeast Asia (SEA) waters are highly dynamic, as manifested in geopolitical tensions and struggles for regional dominance and issues surrounding these marine environments. The high latent complexity of the region is linked to traditional and non-traditional security issues, including claims of sovereignty and competition for economic resources, transportation routes, food, and energy. Loss of marine biological habitats, damage to coral reefs, and air pollution are some issues in the SCS-SEA waters. The states bordering the SCS water area are on the front line of jointly addressing marine environmental challenges while managing the sustainability of markets and catering to the interests of their citizens.
SCS holds approximately 190 trillion cubic meters of natural gas and 11 billion barrels of oil (Basu & Chaturvedi, 2021). In 2016, SCS produced 16.6 million tons of catch from the marine sector, which could sustain the lives of millions of people in ten coastal countries. The United Nations Conference on Trade and Development (UNCTAD) estimated that 80 percent of global trade volume, or 70 percent of the value, is transported by sea and assumed to carry one-third of international shipments (UNCTAD, 2016). These affirmed that the SCS is positioned as a strategic maritime area, both geopolitically and geoeconomically.
Many countries depend on the strategic position and availability of economic resources in SCS waters. China, South Korea, Taiwan, Japan, the members of ASEAN, and a number of extra-regional states also play a part in the strategic competition in SCS waters. Those heavily relying on SCS in their marine sector are considered to be catalysts for environmental problems in the sea, including carbon pollution. The increasing trend of carbon emissions has indeed altered the evolution and chemical cycling in the global atmosphere from Asia to the edge of the Pacific region and it has contributed to a sea level rise of up to ± seven mm from 1900 to 2015 (Tao et al., 2022; Tseng et al., 2018).
The atmospheric circulation above SCS-SEA waters is a complex system that determines the redistribution of air pollutants (Ding et al., 2013). Rapid economic development in the food and energy sector stimulates more activities taking place in and utilizing maritime environments, such as offshore oil drilling, construction of artificial islands, and fishing vessel industries in SCS waters. Nitrogen oxide (NOx), hydrocarbon (HC), sulfur oxide (SOx), and carbon monoxide (CO) are several pollutants in exhaust gas emitted by ships sailing through these waters, affecting air quality and climate change (Wu et al., 2021). Climate change has significantly affected the region, not only in the short term but it also causes hydrological, socioeconomic, and environmental security challenges in the long term. This region has warmed at a much faster rate than the global average and disrupted the water cycle.
CO plays a central role in determining the oxidizing capacity of Earth's atmosphere. It is the primary determinant of tropospheric hydroxyl radical (OH) concentration and, therefore, indirectly affects the atmospheric residence times of greenhouse gases such as methane and halocarbons, which are predominately removed by OH-initiated oxidation. Air temperatures exceeding the global average air temperature result in abnormal evaporation. It affects other components of the water cycle. Evaporation that is too high will result in inconsistent or abnormal precipitation. For instance, rain occurs within a few months, with an average quantity of not more than 150 mm/day in the rainy season. However, due to this abnormality, rainfall occurs in short periods, exceeding the regular rate. Another consequence of abnormal evaporation is that some areas receive excessive precipitation. However, some areas experience drought.
SCS and its surrounding waters are considered a region with crucial roles in international geopolitics, mainly for Southeast, East, and Pacific Asia. Many neighboring countries, even the United States, pay great attention to every regional issue. Unfortunately, the most extensively discussed issues are usually political with major significance, while very few concerns are raised for light, common political issues with isolated impact. However, since the COVID-19 pandemic hit the world with an enormous impact on human survival, international policies have started to change direction. Most countries, government leaders, and the global civil movement have revived environmental sustainability and human security plans into global political agendas.
Climate change due to carbon emissions is predicted to have varied consequences on states bordering SEA-SCS, posing a long-term threat to their welfare and prosperity. Research has found that climate change and sea surface temperature rise push several fish species in SCS further northward (Lau, 2022). CO, one of the greenhouse sources, emerged largely from the ocean. This part led to the ocean releasing more CO, which means that air and water pollution emissions increased. The warmer the ocean, the harder marine microorganisms are to oxidize. The amount of CO in the air also contributes to temperature and weather changes. As a place where the population relies on marine activities, the unpredictable and sudden temperature and weather changes could be troublesome. Without immediate measures, this will lead to reduced income, and people's livelihoods that depend on marine resources will be economically vulnerable. As viewed from satellite images of SEA, millions of people in low-lying lands like Indonesia, Thailand, Vietnam, and the Philippines are at risk of being adversely affected by sea level rise and land subsidence. These countries have announced plans to move their capital city due to frequent heavy flooding in coastal areas (Lau, 2022).
The latest developments in the marine situation show threats and vulnerability of the residents for three reasons: (1) most islands in SCS are in low-lying lands; (2) the livelihoods of densely populated and low-income states and territories on this sea tend to depend on the marine sector and marine environments that continue to change in negative trends potentially reducing the economic security of local communities; and (3) increased mobility in maritime transport contributes to the spread of carbon emissions, resulting in a higher amount of greenhouse gases, accelerated climate change, and sea level rise, which in turn create disasters for the region's economic growth. Ironically, these issues are not perceived and formulated in decision-making as regional threats.
Due to the recent drop in oil and gas exports from Russia and their soaring price in the international market, more countries in SCS and its surrounding waters will rely on coal, which is cheaper but adds a significant amount of carbon gas released to the atmosphere in its combustion. As a result, predictions warn that 2022 and 2023 will significantly contribute to decelerating the pace of climate change. Unfortunately, over the past decade, the region has focused on territorial disputes between China and its Southeast Asian neighbors and geopolitical struggles between China and the United States over freedom of navigation in the contested waters. Consequently, the security of the marine environment is not a priority for countries in the region. However, considering the significance of SCS-SEA waters for many states and populations within and outside of it, climate change driven by CO needs to be investigated—which raises two questions: What is the trend of CO in SCS-SEA waters, and how can this issue be securitized as a regional threat to environmental security?
Methods
The selection of the research theme and method set out from a reflection that Geospatial Information System (GIS) substantially helps observe how a country's political-economical activities impact the environment. Physical environmental data obtained through GIS can be used to analyze a particular location's socioeconomic or political conditions, and GIS has proven to be a powerful tool for examination (Hochstetler & Laituri, 2006).
GIS can answer questions about what, when, and where an action occurs and its temporal pattern in SCS and surrounding waters. Concerning both areas, CO can be used as a variable to determine real dynamics and activity patterns over a certain period. Previous studies used the Google Earth Engine to identify the spatial and temporal pattern of CO (exhaust gas) emission (Kwiecien & Szopinska, 2020).
GIS can also be a tool to analyze an environmental problem and a scientific asset in adding details to supporting regional and international cooperation policy formulation (Branch, 2016). In the context of international relations, it has a significant role in re-formulating current and future decisions in environmental governance and designing its models and strategies. It also bridges interdisciplinary studies of global environmental politics in three ways. The first is identifying spatial data relevant to specific environmental issues. The second is to analyze and visualize spatial data through GIS software and techniques. This could involve overlaying different layers of data, conducting spatial analyses such as proximity analysis or hotspot identification, and generating maps and visualizations. The third incorporates spatial analysis into securitization theory as an effort to construct existential threats in the region. Hence, integrating GIS analysis with the Copenhagen School can offer a more holistic comprehension of how spatial dynamics play a role in shaping the securitization processes within the global political realm of environmental cooperation.
Study area
The study area (Figure 1, red square) is a region where the Southeast Asian waters meet the SCS, lying from 5.38° to 10.91°N and from 108.77° to 115.14°E. Geographically, SCS is connected to the western side of the North Pacific Ocean by the Luzon Strait, to the Sulu Sea by the Mindoro Strait, the Java Sea by the Karimata Sea, and the East China Sea by the Taiwan Strait. Based on the literature review, the research area has a strategic position because it contains two international sea transportation routes: the core and secondary. The two routes connect shipping from the Malacca Strait to the Taiwan Strait and the Luzon Strait. The research area has a high density of sea transportation (Rodrigue, 2017). According to this geographical condition, we highlight the importance of its analysis.
• Study area.
Base map source: (Google Map, 2022)
Citation: Regions and Cohesion 13, 3; 10.3167/reco.2023.130303
Data processing
The most widely used technology to acquire and analyze geospatial data is cloud computing-based Google Earth Engine (GEE), connected to millions of remote sensing big data (Gorelick et al., 2017). GEE can identify phenomena on and above the Earth's surface, including CO's spatial and temporal pattern (Kwiecien & Szopinska, 2020). The study analyzed the current trend of CO above the SCS. Thus, we used the cloud computing platform GEE to analyze the data using the script in Figure 2.
• Script data analysis.
Source: Copernicus Sentinel data (2022) for Sentinel data.
Citation: Regions and Cohesion 13, 3; 10.3167/reco.2023.130303
We obtained the geospatial data from the satellite image Copernicus Sentinel-5P NRTI CO: Near Real-Time Carbon Monoxide from January 2019 to June 2021. It can spatially describe the CO column's total composition with excellent horizontal resolution (Inness et al., 2022). Each pixel in the Copernicus Sentinel-5P NRTI CO satellite imagery has a spatial resolution of 3.5 x 7.5 km. The researchers previously used this type of satellite imagery to identify spatial patterns of CO on local and global scales. Easy data accessibility and excellent validity are the basis for using this data set in the study.
Research period
The research data were collected by observing changes in CO density above SCS-SEA waters every semester, both spatially and temporally. The density was later divided into five periods: January–June 2019, June–December 2019, January–June 2020, June–December 2020, and January–June 2021.
Literature review
Air pollution, especially linked to the chemical evolution of the global atmosphere, is an environmental problem in the SCS and its surrounding waters. Current data show a concerning development since air pollution has spread from the Asian continent to the Pacific Rim (Chan et al., 2002). Also, previous studies have highlighted air pollution as a cause of increased carbon dioxide (CO2) emissions above sea level (Lee et al., 2016). Furthermore, other research findings suggest that the East Asian region is a significant source of anthropogenic air pollutants emitted from fossil fuel ships, and there have been local reports on declining water quality and climatic change (Ding et al., 2013; Wu et al., 2021).
Another study found that China's oil and gas exploration and construction of artificial islands also contribute to the amount of gas contaminating the SCS's waters (Basu & Chaturvedi, 2021). In addition, fossil fuel trade from the ports of Singapore exports up to 42 percent of carbon emissions, with the highest density being in the SCS-SEA waters (Mao et al., 2022). Moreover, in 2019, Singapore, the world's largest bunkering hub, accounted for one-fifth of global marine fuel sales, leaving a trail of global air, water, and climate pollution. Smog due to forest fires from palm oil burning in Indonesia over a certain period has been reported to alter the trend of carbon gas emissions in Peninsular Malaysia and Brunei Darussalam. Even though carbon emissions have indirect effects, incomplete combustion of gases, such as CO, increases the atmospheric concentrations of greenhouse gases, affects human health, and creates a warming effect.
The study of CO in the SCS and its surrounding waters receives insufficient attention, considering its major impact on the states around the region. This gap is at odds with the relevance of existential threats for humanity and the environment, and it also limits the ability of scientific communities to engage with emerging debates and narratives about the existential dimension of climate change that have recently gained considerable traction. This article intends to address this gap by framing CO as an existential threat related to climate change. We argue that the CO emissions trend should be investigated to understand climate change and its significance in global environmental-political studies. This research incorporated analysis and political recognition of the complexity of air pollution as a threat to the marine environment in the region. Employing an international relations theory to construct the empirical data leads to making logical, systematic, and fact-based policies. Therefore, combining geospatial approaches and securitization theory in international relations, this research was intended to develop ways in which an environmental issue can be defined and constructed as an existential threat, both politically and factually.
Bridging environmental securitization and GIS: A framework development
Air pollution, especially linked to the chemical evolution of the global atmosphere, is an environmental problem in the SCS and its surrounding waters. Current data show a concerning development since air pollution has spread from the Asian continent to the Pacific Rim (Chan et al., 2002). Also, previous studies have highlighted air pollution as a cause of increased CO2 emissions above sea level (Lee et al., 2016). Furthermore, other research findings suggest that the East Asian region is a significant source of anthropogenic air pollutants emitted from fossil fuel ships, and there have been local reports on declining water quality and climatic change (Ding et al., 2013; Wu et al., 2021).
Another study found that China's oil and gas exploration and construction of artificial islands also contribute to the amount of gas contaminating the SCS's waters (Basu & Chaturvedi, 2021). In addition, fossil fuel trade from the ports of Singapore exports up to 42 percent of carbon emissions, with the highest density being in the SCS-SEA waters (Mao et al., 2022). Moreover, in 2019, Singapore, the world's largest bunkering hub, accounted for one-fifth of global marine fuel sales, leaving a trail of global air, water, and climate pollution. Smog due to forest fires from palm oil burning in Indonesia over a certain period has been reported to alter the trend of carbon gas emissions in Peninsular Malaysia and Brunei Darussalam. Even though carbon emissions have indirect effects, incomplete combustion of gases, such as CO, increases the atmospheric concentrations of greenhouse gases, affects human health, and creates a warming effect.
The study of CO in the SCS and its surrounding waters receives insufficient attention, considering its major impact on the states around the region. This gap is at odds with the relevance of existential threats for humanity and the environment, and it also limits the ability of scientific communities to engage with emerging debates and narratives about the existential dimension of climate change that have recently gained considerable traction. This article intends to address this gap by framing CO as an existential threat related to climate change. We argue that the CO emissions trend should be investigated to understand climate change and its significance in global environmental-political studies. This research incorporated analysis and political recognition of the complexity of air pollution as a threat to the marine environment in the region. Employing an international relations theory to construct the empirical data leads to making logical, systematic, and fact-based policies. Therefore, combining geospatial approaches and securitization theory in international relations, this research was intended to develop ways in which an environmental issue can be defined and constructed as an existential threat, both politically and factually.
Results: CO trends in the SCS
The high CO density in the SCS was observed during the entire study period. The SCS is home to exploring various resources, military exercises, and small- to large-scale fishing by countries in the SEA-SCS region and beyond. These activities’ accumulation also shapes the CO density in SCS. The International Maritime Organization found that greenhouse gases resulting from distribution by sea in 2018 were 9.6 percent higher than in 2012. This increase added more than 2 percent of emissions to global warming (Millefiori et al., 2021). Visualization of geospatial data from January to June 2019 indicated the highest CO density of 2 to 3.5 mol/m2 at 10.547°N, 108.941°E (Figure 3).
• Spatial and temporal distribution of CO (January–June 2019).
Base map source: (Google Map, 2022)
Citation: Regions and Cohesion 13, 3; 10.3167/reco.2023.130303
Then, this density level lowered in June–December 2019 (Figure 4), although not significantly. The highest density was detected at 10,071°N, 110.490°E. Based on the visualized CO data, there was a decrease in density from what was initially 2–3.5 mol/m2 to 1–2.8 mol/m2, a dominant range during this period. Even though the densities were lower than the previous semester, their spatial pattern was generally similar.
• Spatial and temporal distribution of CO gas (June–December 2019).
Base map source: (Google Map, 2022)
Citation: Regions and Cohesion 13, 3; 10.3167/reco.2023.130303
From January to June 2020 (Figure 5), the highest 2 mol/m2 CO density was at 8.564°N, 109.732°E. This indicated a significant decrease resulting from restrictions on socioeconomic activities and regional to national quarantine or isolation due to the COVID-19 pandemic. The UNCTAD also recorded a decrease in the rate of container ship movement in 2020 in the area during the first quarter of the year and a more significant one in the second quarter. Various responses made by many countries to curb the pandemic's spread, including border closures, were responsible for the lower CO density observed in the area.
• Spatial and temporal distribution of CO gas (January–June 2020).
Base map source: (Google Map, 2022)
Citation: Regions and Cohesion 13, 3; 10.3167/reco.2023.130303
From June to December 2020, the highest density of 1.8 mol/m2 was identified at 10.342°N, 110.171°E (Figure 6). CO above SCS-SEA waters was predominantly at the density of 0.5 to 1.5 mol/m2. The density dropped drastically, resulting from a rise in COVID-19 cases and pandemic-related policies (Guan et al., 2022; Millefiori et al., 2021). At the same time, other pollutants like nitrogen monoxide and black carbon were released at a lower intensity into the atmosphere due to the border closure and travel restriction, which supported the CO trend identified in this article.
• Spatial and temporal distribution of CO gas (June–December 2020).
Base map source: (Google Map, 2022)
Citation: Regions and Cohesion 13, 3; 10.3167/reco.2023.130303
Overall, the presence of CO in the area fluctuated. Despite the plunge in June–December 2020, the overall density remained high. Because of the COVID-19 pandemic, the number, distribution range, intensity of activity, and duration of fishing vessel movement experienced a relatively significant decline. However, from January to June 2021, an increase to 3.3 mol/m2 was recorded (Figure 7). Then, maritime activities rapidly increased after countries in the SCS-SEA waters effectively controlled the pandemic (Guan et al., 2022).
• Spatial and temporal distribution of CO gas (January–June 2021).
Base map source: (Google Map, 2022)
Citation: Regions and Cohesion 13, 3; 10.3167/reco.2023.130303
The density of CO can influence the interactions between the air and sea in specific regions, as well as impact the climate. Furthermore, since certain areas within the SEA-SCS waters play a significant role in the thermohaline circulation, knowing transcontinental maritime transport (MC) is relevant for comprehending global climate change. As anthropogenic warming continues, the world's oceans absorb the excess heat. From 1971 to 2010, up to 63 percent of an increase in this excess heat was at 700 m above sea level (IPCC, 2019). With persistent warming rates into the late 21st century, upper ocean dynamics and marine biogeochemistry are projected to change, potentially exceeding current mean ranges and variability over different timescales. This substantially affects regional ocean dynamics and sea level rise, threatening many low-lying islands. Regardless of which socioeconomic path(s) become a reality in the late 21st century, it is essential to understand how changes in areas above sea level are linked to high carbon emissions.
The changing patterns of CO density in the SCS over a particular period are far from average, considering that this gas is one of the pollutants that accelerates climate change. In addition, the large-scale burning of fossil fuels for marine transportation significantly contributes to the pattern. Datasets on CO emissions provide insight into various activities occurring in the SCS. However, there are some limitations in studying the spatial-temporal variability of upper ocean behavior with these datasets, such as significant regional data gaps, low/grainy horizontal resolution, intermittent time series, lack of longer records, and visibility only at the surface level.
The oxidation of carbon gases into the atmosphere increases the number of greenhouse gases. It raises the temperature on land and sea surfaces, which regulate ecosystem stability and the formation of extreme weather. Coastal areas are most vulnerable to global climate change. Lowlands surround the SCS-SEA waters, and most local communities depend on the sea. Thus, CO has major implications for the stability and security of marine environments and people in the region.
The high trend of CO derived from the analysis indicated that securitization or transformation of CO into a collective threat is needed for three reasons: (1) CO has degraded air quality in the region, changing the marine climate and underwater ecosystem behavior; (2) securitization that enables “extraordinary political actions” can be used by state or non-state actors in the region to “force” contributors of air pollutants to change the use of fossil fuels for environmentally friendly practices; (3) the securitization of air pollution means labeling hazardous contaminants as a threat to the preservation of the environments, people, and countries bordering the SCS-SEA waters.
Regional cooperation that incorporates air pollution due to maritime activities in the SCS-SEA waters is a strategy to mitigate and prevent the adverse impacts of climate change while strengthening the marine resource- dependent economies and mainstreaming the global energy transition. Furthermore, the COVID-19 pandemic should be momentum for every country to take a closer look at the concept of security, not just as matters of war and arms race. Protecting terrestrial and marine environments maintains international stability and environmental sustainability for the world community and human security.
Regional Emission Control Area: Securing the environment, society, and managing the market
There is a consensus in the international community that more effective actions on climate change are needed, as reflected in the Paris Agreement, which was adopted by 195 countries at the end of 2015 as a historic outcome of the United Nations Framework Convention on Climate Change (UNFCCC) to enhance the capacity to deal with climate change impact. So then, how has it influenced pollutant-emitting sectors in the SCS-SEA waters?
Due to the impetus for industrialization, the dependence of countries, their citizens, and various markets in the SCS-SEA waters leads to high economic mobility. At the same time, the region has been increasingly vulnerable, which is expected to continue in the long term. Air pollution harms member states, territories, and world trade without proper handling. Hence, two problems arise. First, maritime cooperation policies in the SEA-SCS region have yet to consider air pollution and the alarming concentration of greenhouse gases. Second, the marine environment's behavior at the surface (i.e., ocean heat content, salinity, and mixed layer depth) is still poorly understood. These problems are exacerbated by the absence of regulations and policies that drive and compel the transition to zero-carbon energy to control regional emissions.
Transboundary Haze Pollution in Southeast Asian countries has yet to accommodate gas emission management in the maritime transportation sector. As inferred from the agreement objective, it is limited to smoke pollution from forest fires. CO trends identified in this article indicate air pollution attributed not only to forest fires but also to burning fossil fuels. Regulatory and control instruments for monitoring and modulating CO amid the increasing maritime activities remain underdeveloped and limited to voluntary measures, leading to sub-optimal plans and actions.
Carbon emissions in the region rife with shipping and resource exploitation have received less scholarly attention in regional environmental politics studies. They have not been explicitly formulated into maritime environmental governance and cooperation. Task forces to oversee and control various regional maritime activities in relation to carbon control are lacking, meaning that carbon emissions are not a political issue. These findings are consistent with comparative scholarship on regional environmental security agendas which have documented the disconnect between environmental and human security at the regional level (see Koff, 2016; Koff and Maganda, 2016). At the same time, CO emissions are a shared political issue because they put the stability of state, human, and environmental security at risk amid the high dependence on resources in the SCS. Despite their indirect effects, these emissions require speech acts from securitization actors to prevent accelerated global warming, sea level rise, and pollution above sea level.
Based on the trend of CO emissions identified in this article, it is imperative that countries bordering the SCS-SEA waters encourage fact-based environmental securitization by formulating Regional Emission Control Areas for all contributors: business actors and fossil fuel users. Guaranteeing clean air means saving countries, environments, and people and regulating the amount of carbon emitted to the atmosphere above the region.
Conclusion
The ASEAN Maritime Cooperation still needs to regulate CO as one of the environmental security issues in the SCS-SEA waters. Awareness of the dangers and impacts of increasing CO in the SCS should encompass the shared agenda that shapes the governance architecture of the marine environment. The argument is straightforward: Southeast Asian waters and the SCS play a crucial role in the survival of states and territories bordering this region and their citizens. The fact that the SCS is a vital route for global trade cannot be separated from the number of shipping vessels, the main means of sea transportation that generate CO in the ocean. Warships (under the argument of providing security in the SCS) also increase the atmospheric concentration of CO, even during the COVID-19 pandemic when non-military ships were temporarily grounded.
The SCS and its surrounding waters are a region that is indivisible from maritime civilization; therefore, it is time for the enclosing countries to look deeper into environmental issues, not solely from the perspective of traditional geopolitical battles. Environmentally friendly sea transportation and sustainable global trade routes in the region should be components of the maritime management formula; this aligns with current efforts to mainstream the world's energy transition and face pressure from dwindling natural resources. High CO emissions before and after the pandemic-related policies worldwide predicate the need to raise and integrate this issue in the framework of regional maritime cooperation to achieve sustainable sea transportation amidst the region's effort to mainstream energy transition.
Except for the representation of security studies in the SCS-SEA waters, this article highlights the possibility of collaborative science to deliver a new way of understanding regional security issues. Securitization studies in Copenhagen schools have so far presented the main concepts descriptively. Besides, accurate scientific data are needed to identify factors that strengthen securitization. This article offers a framework for environmental securitization in Southeast Asian cooperation by involving socio-political and geospatial approaches. Here, geospatial data prove that securitization should be predicated on empirical data, which creates the basis for developing interdisciplinary research between science and politics and incorporating them into global environmental and political cooperation. Technological advances that enable remote sensing make this geospatial political approach an alternative for environmental security studies in international relations to obtain accurate and significant data sources.
The mainstreaming of energy transitions worldwide is momentum for world leaders, supported by an authoritative epistemic community, to construct discourses and take extraordinary action against the existing threats of CO pollution in the SCS-SEA waters. This is especially true since these threats affect the achievement of goals in national and global climate change agendas. The transformation of maritime security policies in the SCS-SEA waters decides to what extent international trade, society, and environmental sustainability can be realized.
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