The Global Carbon Cycle (Interdisciplinary)

Crash Course: The Global Carbon Cycle (Interdisciplinary)

The Global Carbon Cycle: A Crash Course

Introduction Imagine a giant game of carbon tag, where atoms of carbon are being passed around the Earth, from the atmosphere to the oceans, to the land, and back again. But here's the thing: we're the ones who've been tagging the carbon, and it's not a game we're winning.

The Core Idea The global carbon cycle is the movement of carbon through the Earth's atmosphere, oceans, land, and living things. It's like a never-ending game of carbon tag, where carbon is constantly being cycled through the planet. And, just like in the game, we're affecting the rules.

Key Facts & Figures

• 4.4 billion years ago: The Earth's atmosphere was mostly carbon dioxide, with no oxygen.
• 2.7 billion years ago: Oxygen started appearing in the atmosphere, thanks to photosynthetic bacteria.
• Carbon dioxide levels: Today, they're at 415 parts per million (ppm), up from 280 ppm in the 18th century.
• Fossil fuels: We've burned through 1.4 trillion barrels of oil, 7.2 trillion cubic meters of natural gas, and 1.1 trillion tons of coal since the Industrial Revolution.
• Deforestation: We've cleared 13% of the world's forests since the 19th century, releasing stored carbon into the atmosphere.
• Carbon sequestration: The world's oceans absorb about 25% of the carbon dioxide we emit, but that's not enough to balance the books.
• Permafrost: Thawing permafrost could release 1,500 billion metric tons of carbon into the atmosphere by 2100.
• Carbon sinks: Forests, oceans, and soils absorb about 50% of the carbon dioxide we emit, but that's not enough to balance the books.
• Climate change: The global average temperature has risen by 1°C since the late 19th century, and we're on track for a 3°C increase by 2100.
• Carbon pricing: Some countries, like Sweden and Norway, have implemented carbon pricing schemes to reduce emissions.
• Renewable energy: Solar and wind power now account for 10% of global electricity generation, up from 2% in 2010.

Thought Bubble Imagine you're a carbon atom, floating through the atmosphere. You're part of a molecule of carbon dioxide, CO2. You're carried by the wind to a forest, where you're absorbed by a tree. The tree uses you to build its leaves, and you're part of the food chain. But then, the tree dies, and you're released back into the atmosphere. You're part of the carbon cycle, and it's a never-ending game.

Why This Matters

• Climate change: The global carbon cycle is driving climate change, which affects everything from sea levels to extreme weather events.
• Ecosystems: Changes to the carbon cycle are impacting ecosystems, from coral reefs to forests.
• Food security: Climate change is affecting crop yields and food security, which affects human populations.
• Economic impacts: Climate change is already costing the global economy trillions of dollars per year.
• Human health: Climate change is linked to increased mortality rates, respiratory problems, and other health issues.
• Sustainability: The global carbon cycle is a key indicator of sustainability, and we need to get it right to ensure a livable future.
• Policy: Governments and corporations are starting to take action on carbon pricing, renewable energy, and carbon sequestration.

Crash Course Recap

• ⚠️ Carbon dioxide levels: We've increased CO2 levels by 50% since the Industrial Revolution.
• Photosynthesis: Plants absorb CO2 and release oxygen, which is essential for life.
• Fossil fuels: We've burned through massive amounts of fossil fuels since the Industrial Revolution.
• Deforestation: We've cleared 13% of the world's forests since the 19th century.
• Carbon sequestration: The world's oceans absorb about 25% of the carbon dioxide we emit.
• Permafrost: Thawing permafrost could release 1,500 billion metric tons of carbon into the atmosphere by 2100.
• Carbon sinks: Forests, oceans, and soils absorb about 50% of the carbon dioxide we emit.
• Climate change: The global average temperature has risen by 1°C since the late 19th century.
• Renewable energy: Solar and wind power now account for 10% of global electricity generation.
• Carbon pricing: Some countries have implemented carbon pricing schemes to reduce emissions.

Quiz Yourself

1. What percentage of the world's forests have we cleared since the 19th century? a) 5% b) 13% c) 20%

Answer: b) 13%

1. What percentage of the carbon dioxide we emit is absorbed by the world's oceans? a) 10% b) 25% c) 50%

Answer: b) 25%

1. How much carbon could be released from thawing permafrost by 2100? a) 500 billion metric tons b) 1,500 billion metric tons c) 2,000 billion metric tons

Answer: b) 1,500 billion metric tons

1. What percentage of global electricity generation comes from solar and wind power? a) 2% b) 5% c) 10%

Answer: c) 10%

1. What is the current level of carbon dioxide in the atmosphere? a) 280 ppm b) 415 ppm c) 500 ppm

Answer: b) 415 ppm