Enhanced Oceanographic Research Needed to Address Ocean Crises

Context:

Recently, the UNESCO State of Ocean Report 2024 highlighted the need for enhanced oceanographic research and data collection to address escalating ocean crises, including warming, acidification, deoxygenation, and rising sea levels.

Relevance:

GS III: Environment and Ecology

Dimensions of the Article:

1. Key Findings of the State of Ocean Report 2024:
2. Effects of Global Warming on the Indian Ocean
3. Way Forward

Key Findings of the State of Ocean Report 2024:

Data and Research Gap:

• The report highlights a crucial lack of data and research on the rapid warming of oceans, emphasizing the need for ongoing data collection to monitor and address the impacts on ocean health and resilience.

Ocean Warming Trends:

• The upper 2,000 meters of oceans have warmed at a rate of approximately 0.32 Watt/m² from 1960 to 2023, which has increased to 0.66 Watt/m² in the last two decades.

This warming is expected to persist, leading to irreversible changes over the long term.

Earth Energy Imbalance (EEI):

• Human activities have increased greenhouse gas emissions, resulting in the oceans absorbing more EEI.
• EEI represents the balance between the energy the Earth receives from the Sun and the energy it emits back into space.
• Around 90% of this imbalance is being absorbed by the oceans, causing a rise in ocean heat content (OHC) in the upper 2,000 meters of the water column.

Ocean Heat Content (OHC):

• The oceans are storing more heat, which might inhibit ocean layer mixing and reduce oxygen levels, leading to deoxygenation.

Deoxygenation:

• This process can have adverse long-term effects on the health of coastal and large marine ecosystems and the communities that rely on them.

Ocean Acidification:

• There is a global increase in ocean acidification across all ocean basins and seas.
• The open ocean has seen a continuous decline in pH levels, with an average decrease of 0.017-0.027 pH units per decade since the late 1980s.
• Coastal waters can also become acidic due to natural processes and human activities like nutrient runoff from agriculture and industry.

Rising Sea Levels:

• From 1993 to 2023, the global mean sea level has risen at a rate of about 3.4 mm per year.
• Enhancing space-based and in situ observing systems is necessary for monitoring sea level rise on global, regional, and coastal scales.

Marine Carbon Dioxide Removal (mCDR):

• The report recognizes the growing interest in mCDR technologies aimed at capturing and storing atmospheric CO2.
• Techniques include altering seawater chemistry or adding nutrients like iron to stimulate the growth of microscopic plankton that can sequester carbon.

Challenges and Research Needs:

• Interest in mCDR technologies is increasing, with support from start-ups, the United States, and the European Union.
• Challenges include the limited implementation of mCDR and potential unintended effects on the ocean carbon cycle, which could threaten marine life in the long term.

Effects of Global Warming on the Indian Ocean

• Warming Trends: The Indian Ocean is heating up faster than other oceans, which can lead to irreversible changes, including more frequent cyclones and heatwaves.
• Monsoon and Cyclone Formation: The Indian Ocean is crucial in forming monsoons and pre-monsoon cyclones, impacting South Asia, East Africa, and West Asia.
• Cyclone Characteristics: Although the North Indian Ocean produces fewer cyclones compared to the Pacific or Atlantic Oceans, these storms are intensifying more rapidly, becoming increasingly deadly.
• Case Study – Cyclone Fani: In 2019, Cyclone Fani caused significant damage in Odisha, India, due to its strong winds and storm surge.
• Marine Heatwaves: These are becoming more common and severe, leading to coral bleaching and negatively affecting marine life. For example, the 2010 marine heatwave in the Indian Ocean resulted in extensive coral bleaching in the Lakshadweep Islands.
• Impact on Upwelling: Ocean warming can reduce upwelling, which brings cooler, nutrient-rich waters to the surface, affecting fish populations that rely on these nutrients. The Arabian Sea has seen a decline in upwelling, impacting the sardine fishery.
• Ocean Acidification: Increased absorption of carbon dioxide makes oceans more acidic, harming marine organisms with calcium carbonate structures, such as corals and shellfish. The Great Barrier Reef in Australia and coral reefs in the Indian Ocean are already experiencing significant damage.
• Oxygen Depletion: Warmer waters hold less oxygen. Increased stratification due to warming can hinder deep ocean mixing, leading to deoxygenation in deeper layers and creating dead zones where marine life cannot survive.
• Food Security Threats: Disruptions in fisheries, cyclones, and droughts pose risks to the food security of millions who depend on the Indian Ocean.
• Rising Sea Levels: Global warming causes sea levels to rise, threatening coastal communities with flooding and erosion. Low-lying areas in India, like Mumbai and Kolkata, are especially at risk.
• Tourism and Recreation Impact: Industries relying on healthy coral reefs and beaches will suffer from bleaching and coastal degradation.

Way Forward

• Real-Time Weather Forecasting: Improve real-time weather forecasts and cyclone warnings for coastal communities. India can enhance the capabilities of the Indian National Centre for Ocean Information Services (INCOIS) for more accurate and timely predictions.
• Geo-Engineering Solutions: Implement large-scale geo-engineering techniques such as stratospheric aerosol injection and marine cloud brightening to address oceanic warming.
• Sustainable Coastal Development: Promote practices that build seawalls and levees to minimize infrastructure and community damage during extreme weather events. For instance, planting casuarina trees along the Odisha coast has proven effective in mitigating cyclone impacts.
• Public Awareness and Drills: Conduct awareness campaigns and regular evacuation drills to educate coastal communities about cyclone risks and evacuation procedures.
• Marine Protected Areas: Establish protected areas to conserve coral reefs and other fragile ecosystems.
• International Collaboration: Foster international efforts to address climate change and limit global warming, benefiting the Indian Ocean in the long term.

-Source: Down To Earth