Energy and Environmental Dynamics Revision Sheet

1. 📌 Essentials

• Energy is the capacity to perform work enabling physical and societal transformations.
• The conservation of energy states energy cannot be created or destroyed, only transformed.
• Fossil fuels comprise approximately 77% of current global energy consumption (2023).
• Human population has grown from 1 billion in 1850 to over 8 billion today, driving energy demand.
• CO₂ emissions are directly linked to energy use, contributing to climate change.
• Limiting global warming to 2°C requires capping total CO₂ emissions around 3,000 billion tons.
• Planetary Boundaries define Earth's safe operating space; many are exceeded, risking irreversible change.
• Biodiversity is threatened by habitat destruction, pollution, invasive species, and climate change.
• Ecosystems currently act as carbon sinks but may become sources due to degradation.
• Unchecked biodiversity loss and environmental degradation threaten ecosystem services essential for life.