Study Guide: Topic 1A & 1B – Sustaining a Planet

Land Surface Degradation

Damage to Earth’s surface caused by urbanization, deforestation, soil erosion, and habitat loss.

Resource Depletion

Overuse of energy, water, materials, and extraction of non-renewable resources.

Population Growth

Increase in population, particularly significant in developing countries, leading to strain on resources.

Water Cycle Issues

Problems such as droughts, floods, and pollution affecting rivers and aquifers.

Atmospheric & Global Change

Changes including air pollution, ozone depletion, smog, global warming, and sea level rise.

Ecosystems

Communities of living organisms which can experience biodiversity loss due to human activities.

Dead Zone (Gulf of Mexico)

A low oxygen zone caused by nutrient runoff, leading to algal blooms that kill marine life.

Carbon Dioxide Trend

A rapid increase in atmospheric CO₂ levels from ~280 ppm pre-industrial to 428 ppm, linked to fossil fuels and deforestation.

Tipping Points

Critical thresholds beyond which changes in environmental conditions become irreversible.

Sustainable Development

Developing in a way that meets present needs without compromising the ability of future generations to meet theirs.

Sustainability

The practice of meeting present needs without compromising future generations' ability to meet their own needs, as defined by the Brundtland Commission.

Sustainability Science

The interdisciplinary study of interactions between nature and society to achieve sustainability.

Generation Q

Critique of digital activism; emphasizes the need for real action beyond social media support.

Power of One vs. Power of Many

Concept differentiating between individual initiatives and collective action in promoting change.

Greenhouse Effect

Natural process where certain gases trap outgoing infrared radiation, warming Earth’s surface.

Greenhouse Gases (GHGs)

Gases that trap heat in the atmosphere, including CO₂, CH₄, N₂O, and others.

Positive Feedback

A climate feedback mechanism that amplifies changes, such as ice melt leading to greater warmth.

Negative Feedback

A climate feedback mechanism that stabilizes changes, like increased vegetation absorbing more CO₂.

Energy Budget

The balance between incoming solar radiation and outgoing terrestrial radiation that governs Earth's climate.