Report on the State of Global Coral Reefs and Alignment with Sustainable Development Goals

1.0 Introduction: The Critical Role of Coral Reefs in Sustainable Development

Coral reef ecosystems are fundamental to achieving several Sustainable Development Goals (SDGs), yet they are among the most vulnerable habitats on Earth. Occupying just 0.1% of the Earth’s surface, their contributions are disproportionately large. This report outlines the critical functions of coral reefs and analyzes the anthropogenic threats that jeopardize their existence and undermine global sustainability targets.

• SDG 14 (Life Below Water): Coral reefs support over a quarter of all marine species, making them epicenters of biodiversity.
• SDG 11 (Sustainable Cities and Communities): They provide critical coastal protection by absorbing up to 97% of wave energy, safeguarding coastal communities from erosion and storm surges.
• SDG 2 (Zero Hunger) & SDG 1 (No Poverty): Reefs are a primary source of food and livelihoods for millions of people globally.
• SDG 3 (Good Health and Well-being): They are a source of compounds used in modern medicine.

Despite their importance, an estimated half of the world’s coral reefs have been lost since 1950. The continued degradation of these ecosystems poses a direct threat to the achievement of these SDGs.

2.0 Analysis of Key Threats and Impacts on Sustainable Development

The primary drivers of coral reef decline are linked to climate change and pollution, directly conflicting with the objectives of the SDGs. The following sections detail the five principal threats.

2.1 Coral Bleaching and Rising Sea Temperatures

Coral bleaching is a direct consequence of rising global temperatures, a critical concern for SDG 13 (Climate Action). The process involves the expulsion of symbiotic zooxanthellae algae from coral tissue when water temperatures become too high. This not only strips the coral of its color but also removes its primary food source, leading to starvation and death.

• If global temperatures rise to 1.5°C above pre-industrial levels, up to 90% of tropical coral reefs may be lost by 2050.
• A fourth global bleaching event (2023-2025) has impacted nearly 84% of the world’s reefs.
• In 2023, Jamaica experienced a severe bleaching event, resulting in the loss of approximately 90% of its corals in a two-month period.

This widespread loss of coral directly undermines SDG 14 (Life Below Water) by destroying critical marine habitats.

2.2 Ocean Acidification

Ocean acidification, driven by the absorption of atmospheric carbon dioxide (CO2), presents a significant challenge to SDG 13 (Climate Action) and SDG 14 (Life Below Water). The ocean absorbs approximately 30% of anthropogenic CO2, which forms carbonic acid and lowers the water’s pH.

• Increased acidity reduces the availability of carbonate ions, which are essential for corals to build their aragonite skeletons.
• In highly acidic conditions, existing coral skeletons can begin to dissolve.
• Monitoring efforts, such as the ocean acidification buoy in Puerto Rico, are in place to track this threat and inform mitigation strategies.

2.3 Extreme Weather Events

Climate change is increasing the intensity and frequency of extreme weather events, such as tropical cyclones, which physically devastate reef structures. This phenomenon is a key indicator of the challenges addressed by SDG 13 (Climate Action).

• The intensity of cyclones has risen over the past 30 years, particularly in the Atlantic and Caribbean regions.
• In Southwest Madagascar, cyclones between 2012 and 2015 caused a decrease in coral cover of up to 45.8% across 19 sites.

The destruction of reefs by storms weakens natural coastal defenses, increasing the vulnerability of coastal populations and infrastructure, thereby impacting progress toward SDG 11 (Sustainable Cities and Communities).

2.4 Plastic and Debris Pollution

Plastic pollution is a pervasive threat that compromises progress on SDG 12 (Responsible Consumption and Production) and SDG 14 (Life Below Water). Both macroplastics and microplastics inflict harm on coral ecosystems.

• Microplastics can impede coral growth, interfere with feeding, and cause corals to expend energy on removal.
• A recent study found human-generated debris, 88% of which was macroplastics, in 77 of 84 surveyed reefs across three oceans.

These findings highlight the urgent need for improved waste management and a reduction in plastic production to protect marine environments.

2.5 Chemical Pollution from Consumer Products

Chemicals from consumer products, particularly sunscreens, exacerbate the stress on coral reefs. This issue highlights a conflict between consumer choices and environmental health, relevant to SDG 12 (Responsible Consumption and Production) and SDG 3 (Good Health and Well-being).

• An estimated 14,000 tons of sunscreen enter the world’s oceans annually.
• Chemicals such as oxybenzone (BP-3) and benzophenone-2 (BP-2), found in over 3,500 skincare products, are proven to increase coral bleaching, damage DNA, and cause mortality in juvenile corals.
• These pollutants enter marine systems directly from swimmers and through wastewater discharge, impacting reefs in the Caribbean and Indo-Pacific.

Regulatory actions, such as Hawaii’s ban on harmful sunscreens, represent a step toward mitigating this threat to SDG 14 (Life Below Water).

3.0 Recommendations and Strategic Actions for Mitigation

To protect global coral reefs and ensure progress toward the Sustainable Development Goals, a multi-faceted approach is required. The following actions are recommended for governments, industries, and individuals:

1. Advance Responsible Consumption (SDG 12): Promote the widespread adoption of mineral-based, coral-safe sunscreens and raise consumer awareness about the environmental impact of chemical-based products.
2. Strengthen Global Governance (SDG 17): Support and implement international agreements like the Global Plastics Treaty to establish binding targets for reducing plastic pollution at its source.
3. Accelerate Climate Action (SDG 13 & SDG 7): Advocate for and invest in a rapid transition to renewable energy sources to reduce greenhouse gas emissions, addressing the root causes of ocean warming and acidification.

1. Which SDGs are addressed or connected to the issues highlighted in the article?

SDG 14: Life Below Water

• The article’s central theme is the degradation of coral reefs, which are critical marine ecosystems. It discusses threats like pollution, ocean acidification, and the loss of marine biodiversity that depends on these reefs. The text states that reefs “support over a quarter of all marine species on Earth.”

SDG 13: Climate Action

• The article explicitly identifies climate change as the “main culprit” behind the destruction of coral reefs. It details how rising global temperatures lead to coral bleaching, ocean acidification, and more extreme weather events like intense cyclones, all of which directly harm or destroy reef ecosystems.

SDG 12: Responsible Consumption and Production

• The article links the damage to coral reefs to specific consumption patterns. It highlights the negative impact of plastic pollution from tourism and the use of sunscreens containing harmful chemicals like oxybenzone and BP-2. It calls for consumers to switch to “mineral-based” sunscreens and supports initiatives like the “Global Plastics Treaty” to reduce plastic pollution.

2. What specific targets under those SDGs can be identified based on the article’s content?

SDG 14: Life Below Water

1. Target 14.1: By 2025, prevent and significantly reduce marine pollution of all kinds, in particular from land-based activities, including marine debris and nutrient pollution.
   • This target is addressed through the discussion of plastic pollution, where a study found “human-generated debris” in most surveyed reefs, and chemical pollution from sunscreen, with an estimated “14,000 tons of sunscreen end up in our oceans annually.”
2. Target 14.2: By 2020, sustainably manage and protect marine and coastal ecosystems to avoid significant adverse impacts… and take action for their restoration.
   • The article highlights the failure to meet this target by stating that “half of the planet’s coral reefs have been lost since 1950” and that up to “90% of tropical coral reefs may disappear by 2050.” The entire article is a call to action for the protection of these ecosystems.
3. Target 14.3: Minimize and address the impacts of ocean acidification, including through enhanced scientific cooperation at all levels.
   • The section “Acidic Waters” directly addresses this target. It explains how increased atmospheric CO2 makes oceans more acidic, which dissolves the calcium carbonate skeletons of corals. It also mentions scientific cooperation through the “ocean acidification buoy” in Puerto Rico used to monitor the problem.

SDG 13: Climate Action

1. Target 13.1: Strengthen resilience and adaptive capacity to climate-related hazards and natural disasters in all countries.
   • The article connects climate change to “more extreme weather events,” noting that the intensity of cyclones has risen. It describes the “physical damage” these storms cause to reefs, which diminishes their ability to protect coastlines by absorbing “97% of wave impact,” thus reducing coastal resilience to natural disasters.
2. Target 13.3: Improve education, awareness-raising and human and institutional capacity on climate change mitigation, adaptation, impact reduction and early warning.
   • The article itself is an example of fulfilling this target. Published for “Coral Reef Awareness Week,” its purpose is to educate the public on how climate change impacts coral reefs and to raise awareness about mitigation actions.

SDG 12: Responsible Consumption and Production

1. Target 12.4: By 2020, achieve the environmentally sound management of chemicals and all wastes throughout their life cycle… and significantly reduce their release to air, water and soil.
   • This is relevant to the article’s discussion of harmful chemicals in sunscreen, such as “oxybenzone, or BP-3,” and “Benzophenone-2, or BP-2,” which wash off swimmers or enter the ocean via wastewater, harming coral. It also relates to the problem of plastic waste, where “macroplastics accounting for 88% of this detritus” are found on reefs.

3. Are there any indicators mentioned or implied in the article that can be used to measure progress towards the identified targets?

Indicators for SDG 14 (Life Below Water)

• Indicator for Target 14.2 (Ecosystem Health): The article provides several quantitative data points that serve as proxy indicators for coral reef health and coverage. These include:
  • Percentage of coral reef loss over time: “half of the planet’s coral reefs have been lost since 1950.”
  • Percentage of reefs affected by bleaching: “fourth global bleaching event that has impacted nearly 84% of the world’s reefs between January 1, 2023 and May 31, 2025.”
  • Specific regional coral mortality rates: “90% of the nation’s [Jamaica’s] corals died in a two month span.”
  • Change in coral cover due to specific events: “decrease of up to 45.8% of coral cover at 19 sites [in Madagascar]… as a result of cyclones.”
• Indicator for Target 14.3 (Ocean Acidification): The article mentions a direct method of measurement related to the official indicator (Average marine acidity). It describes an “ocean acidification buoy… [that] measures carbon dioxide levels in the air and water to monitor the acidity of the waters.”
• Indicator for Target 14.1 (Marine Pollution): The article provides data that can measure the scale of pollution:
  • Volume of chemical pollutants: “14,000 tons of sunscreen end up in our oceans annually.”
  • Prevalence of plastic debris: A study found “human-generated debris” in “77 out of 84 surveyed reefs.”

Indicators for SDG 13 (Climate Action)

• Indicator for Target 13.1 (Resilience to Hazards): The article provides a metric for the disaster risk reduction service provided by reefs: their ability to absorb “97% of wave impact.” The loss of reefs can be used as an inverse indicator of declining coastal resilience.

4. Create a table with three columns titled ‘SDGs, Targets and Indicators” to present the findings from analyzing the article. In this table, list the Sustainable Development Goals (SDGs), their corresponding targets, and the specific indicators identified in the article.

Source: earthday.org