Oceans have been warming nearly twice as fast since 2005 due to human-caused climate change, according to the Copernicus Marine Service report.
Accelerating Ocean Warming: A Clear Indicator of Global Climate Change
- Oceans, which cover 70% of the Earth’s surface, play a crucial role in regulating global climate.
- Continuous Rise in Ocean Temperature:
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- Ocean warming has been ongoing since the 1960s but has sharply increased since 2005.
- The warming rate has nearly doubled, from 0.58 watts per m² to 1.05 watts per m² over the past two decades.
- Ocean Warming Reflects Global Warming: Ocean warming is seen as a clear indicator of global warming.
- It absorbs 90% of excess heat from the atmosphere caused by carbon dioxide and other greenhouse gases, as reported by the IPCC.
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About Ocean Warming
- The ocean absorbs extra heat from greenhouse gases, causing the water temperature to increase.
Reasons for Ocean Warming-
- Greenhouse Gas Emissions: Burning fossil fuels, cutting trees, and industrial activities release gases like carbon dioxide (CO2) and methane (CH4) that trap heat, making the atmosphere and oceans warmer.
- CO2 Absorption: The ocean absorbs excess CO2 from human activities. While this helps reduce climate change, it also causes ocean warming.
- Solar Radiation: Changes in solar energy can also increase ocean temperatures over long periods, but it’s a small factor compared to human activities.
- Rising sea surface temperatures: Implications:
- Marine biodiversity loss
- Weak reef ecosystem
- Disruption of food web
- Disruption of ocean currents
Key Findings of the Report
- Status of warming of oceans
- Marine Heatwaves: In 2023, 20% of the world’s oceans experienced severe marine heatwaves, affecting marine life and ecosystems.
Longer Marine Heatwaves: The average duration of marine heatwaves has doubled since 2008, from 20 days to 40 days annually.- Permanent Heatwave in the Arctic: Parts of the Arctic, particularly the north-east Barents Sea, have entered a state of permanent marine heatwave.
- Impact of Ocean warming (CMS report)
- Severe Weather Events: Warmer oceans fuel storms, hurricanes, and extreme weather by influencing global weather patterns.
- Mass migration: Marine heatwaves can cause mass migration and mortality of species, disrupting ecosystems and nutrient distribution.
- Sea Ice Loss and Record Temperatures: 2023 saw the lowest sea ice levels on record in the polar regions.
- In August 2022, the Balearic Islands recorded their warmest coastal waters in 40 years at 29.2°C.
- Coral Bleaching: Warmer water causes corals to lose algae that they need to survive, leading to coral bleaching and making them more prone to diseases, which harms coral reefs.
- Sea Level Rise: Warmer oceans cause water to expand and polar ice to melt, raising sea levels. This leads to coastal erosion and makes coastal areas more vulnerable.
- Disruption of Marine Food Webs: Rising temperatures change the distribution of marine species, disrupting the food chain and impacting fisheries and communities that depend on them.
- Increased Ocean Acidity: Ocean acidity has increased by 30% since 1985 due to climate change, primarily from burning fossil fuels.
- This increasing acidity threatens marine species like corals, mussels, and oysters, affecting their ability to form skeletons and shells.
- It damages fragile ecosystems, and disrupts the flow of nutrients in the ocean.
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Role of Oceans in the Global Carbon Cycle (CMS Report)
- Oceans as a Carbon Sink: Oceans play a significant role in absorbing human-made CO2, helping to moderate climate change.
- CO2 Uptake Since the 1980s: According to the IPCC, oceans have absorbed about 20-30% of carbon dioxide emissions caused by humans since the 1980s.
- Annual Absorption: Each year, oceans absorb around 25% of the CO2 released from fossil fuels, cement production, and land-use changes.
Sustainable Development Goals (SDG) and Ocean Acidification
- SDG 14.3: Minimising ocean acidification is one of the goals under the Sustainable Development Goal 14: Life Below Water.
- This involves promoting scientific cooperation to address the issue.
- Monitoring Efforts: The Intergovernmental Oceanographic Commission (IOC) of UNESCO is responsible for monitoring ocean acidity (pH).
- It follows scientific best practices to ensure accurate data collection and reporting from selected sampling locations.
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October 1, 2024
