Ch. 7- Humans and Global Change

The Great Acceleration

The period beginning around the mid-20th century when human activity (population growth, industry, energy use, pollution, and resource consumption) increased dramatically, causing major environmental changes worldwide

The Anthropocene

A proposed geological epoch in which humans are the dominant force shaping Earth’s climate, ecosystems, and geological processes through pollution, land use, and resource exploitation

Smog

A harmful mixture of smoke and fog caused mainly by vehicle emissions and industrial pollution; reduces air quality and harms human health and ecosystems

Ozone Depletion

The thinning of Earth’s ozone layer caused by chemicals like CFCs, which allows more harmful UV radiation to reach Earth’s surface

Global Warming

The long-term increase in Earth’s average temperature due to rising greenhouse gases such as CO₂ and methane

Acid Precipitation (Acid Rain)

Precipitation made acidic by air pollutants (like sulfur dioxide and nitrogen oxides) that damage ecosystems, soils, water systems, and buildings

Biological Magnification

The increase in concentration of toxic substances as they move up the food chain, affecting top predators the most

Extinction

The permanent disappearance of a species from Earth

Climate Change

Long-term shifts in temperature, weather patterns, and climate systems, largely driven today by human greenhouse gas emissions

Ocean Acidification

The decrease in ocean pH caused by absorption of excess CO₂ from the atmosphere, harming organisms like corals and shellfish

Deforestation

The large-scale removal of forests, often for agriculture, logging, or development, leading to habitat loss and climate impacts

Habitat Loss

The destruction or alteration of natural environments, making them unsuitable for species survival

Habitat Fragmentation

The breaking of large habitats into smaller isolated patches, reducing biodiversity and limiting species movement

Habitat Restoration

The process of repairing damaged ecosystems to return them to a more natural and functional state

Invasive Species

Non-native species introduced to an ecosystem that spread rapidly and disrupt native species and ecological balance

Pollution

The introduction of harmful substances or energy into the environment, negatively affecting organisms and ecosystems

Climate Change Impacts

Rising sea levels, extreme weather events, shifting ecosystems, loss of biodiversity, disrupted food and water supplies, and changes in species distribution

Sustainable Development

Development that meets present needs without compromising the ability of future generations to meet their own needs, balancing environmental, social, and economic factors

Keystone Species

A species that has a major impact on its ecosystem despite being relatively low in abundance; its removal can cause dramatic changes in ecosystem structure and biodiversity