IB Biology Topic D4.3: Climate Change Key Definitions

Albedo ($\alpha$) measures the reflectivity of a surface.

Anthropogenic refers to changes in the environment caused by human activities.

Carbon sequestration refers to the process of capturing and storing carbon dioxide (CO₂) from the atmosphere to mitigate the effects of climate change.

Long-term shifts in temperature, precipitation, and other environmental factors that can alter the conditions of an ecosystem.

Evolution is defined as a change in the heritable characteristics of a population over time.

A greenhouse gas is a gas that contributes to the greenhouse effect by absorbing infrared radiation

Ice that is attached to the coastline or the sea floor, remaining stationary.

Natural selection is the process where individuals with traits better suited to their environment have higher reproductive success, passing these traits to the next generation.

Pathogen refers to any organism or agent capable of causing disease.

Ground that remains frozen for two or more consecutive years, typically found in polar regions.

pH is a measure of how acidic or basic a solution is, ranging from 0 (very acidic) to 14 (very basic).

A relationship where an increase in one variable corresponds to an increase in another.

A process where an initial change causes further changes that amplify the original effect, making it stronger and self-reinforcing.

A range shift refers to the movement of a species’ habitat in response to environmental changes, such as climate warming.

Ice that floats on the ocean surface and is not anchored to the land.

The simultaneous occurrence of events at the same time, leading to optimal interactions between species in an ecosystem.

A tipping point is the critical threshold where a small change in conditions (like temperature or moisture) causes a dramatic shift in an ecosystem.

The movement of deep, cold, nutrient-rich water to the surface, usually driven by wind and ocean currents.