Climate change: what is ocean acidification?

Summary

The video script addresses the alarming issue of ocean acidification, a lesser-known but critical consequence of increased carbon dioxide levels. It details the impacts on marine life, particularly deep-sea coral reefs and shelled creatures, which are experiencing thinning shells and ecosystem collapse. The script features explorer Vanessa O'Brien's journey to the Challenger Deep and her contribution to scientific research. It also discusses the economic repercussions for communities reliant on marine resources and explores potential solutions, including reducing CO2 emissions and innovative carbon capture technologies. The urgency to mitigate this 'evil twin' of climate change is emphasized to preserve marine ecosystems and human livelihoods.

Takeaways

• 🌊 Ocean acidification is a serious environmental issue threatening marine life, akin to removing the foundational bricks from deep-sea coral ecosystems.
• 🌍 Human activities, particularly the increased carbon dioxide levels in the water due to burning fossil fuels, are causing this phenomenon, which is often referred to as 'climate change's evil twin'.
• 🐚 The Natural History Museum's research indicates a significant thinning of marine organism shells, highlighting the impact of ocean acidification over the past 150 years.
• 📉 The ocean's pH level has dropped from 8.2 to around 8.05 since the Industrial Revolution, representing an increase in acidity of about 40 percent.
• 🔍 Washington state has been identified as a key area where ocean acidification first manifested, impacting oyster farmers and local economies.
• 🐟 The chemical changes in the ocean are particularly detrimental to marine animals that rely on forming shells, such as oysters and corals.
• 🌿 Seagrass and kelp, when grown underwater, can absorb carbon, potentially helping to mitigate the effects of ocean acidification.
• 🔬 Dr. Sebastian Henninger's research points to ocean acidification as a primary cause of coral porosis, a condition leading to the dissolution of coral skeletons.
• 🐠 Declines in salmon populations and size are linked to ocean acidification, as it affects their food source, the pteropods, which are experiencing shell dissolution.
• 🌱 Addressing ocean acidification requires a multifaceted approach, including reducing CO2 emissions, utilizing technology for carbon capture from the sea, and growing underwater plants to absorb carbon.

Q & A

What is ocean acidification, and why is it called the 'evil twin' of climate change?

Ocean acidification refers to the increase in ocean acidity due to the absorption of carbon dioxide (CO2) from the atmosphere. It's called the 'evil twin' of climate change because, like climate change, it is driven by CO2 emissions and has devastating effects on marine life and ecosystems.

How does ocean acidification affect marine ecosystems, specifically coral reefs?

Ocean acidification weakens coral reefs by dissolving their skeletons, leading to a condition called 'coral porosis,' similar to osteoporosis in humans. This causes coral ecosystems to collapse, which threatens the biodiversity that depends on these reefs for survival.

What evidence is there to show that ocean acidification is impacting marine life?

A study by the Natural History Museum in 2020 compared shelled organisms from 1875 to those from the same area today, revealing that modern shells are up to 76% thinner. This thinning is a result of ocean acidification, which makes it difficult for marine animals to form and maintain shells.

Why is Washington state considered 'Ground Zero' for ocean acidification?

Washington state is considered 'Ground Zero' because oyster farmers in the early 2000s experienced massive stock losses due to baby oysters being unable to form shells, marking the first significant identification of ocean acidification’s direct impact on marine life.

What are the predicted long-term impacts of ocean acidification by the end of this century?

By the end of the century, ocean acidity is expected to increase by 150%, leading to further disruptions in marine ecosystems, with severe consequences for marine species, food chains, and human livelihoods reliant on the ocean.

How is ocean acidification linked to the food chain, especially for species like salmon?

Ocean acidification affects small creatures like pteropods, which are a key food source for species like salmon. As the shells of pteropods dissolve, their populations decline, which disrupts the food chain and negatively impacts larger species that rely on them, including salmon.

What are pteropods, and why are they important in the context of ocean acidification?

Pteropods, often referred to as 'sea butterflies,' are small planktonic snails that are a crucial food source for many marine species, including salmon. They are considered an indicator species because their shells dissolve in acidic waters, highlighting the effects of ocean acidification.

What role do carbon dioxide emissions play in ocean acidification?

Carbon dioxide emissions are the main driver of ocean acidification. As CO2 levels in the atmosphere increase, more CO2 is absorbed by the ocean, leading to chemical changes that lower the pH and increase acidity, which disrupts marine life and ecosystems.

What solutions are being proposed to mitigate the effects of ocean acidification?

Proposed solutions include reducing carbon dioxide emissions, growing seagrass and kelp (which absorb CO2), and using technology to capture CO2 directly from the ocean. However, these measures will be limited in impact without significant reductions in atmospheric CO2.

What is the significance of the research conducted on the Californian coral systems?

The Californian coral systems serve as a 'window into the future' because they provide insights into how ocean acidification might affect deep-sea coral ecosystems globally. The collapse of these coral structures in California could foreshadow similar effects elsewhere.