Climate And Biomes

Characterize the changes in temperature/available sunlight from the equator to the poles. Explain how the curvature of Earth influences these changes.

Temperature and sunlight are highest at the equator and decrease toward the poles. Because Earth is curved, sunlight strikes the equator more directly, concentrating energy in a smaller area, while at higher latitudes, sunlight spreads over a larger area and passes through more atmosphere, reducing its intensity.

Characterize the changes in precipitation from the equator to the poles. Explain how patterns of temperature/sunlight influence patterns of precipitation and global air circulation.

Warm air at the equator rises, cools, and releases moisture, creating high rainfall near the equator. As the air moves poleward and sinks around 30° latitude, it becomes dry, forming deserts. This pattern repeats with alternating wet and dry regions due to global air circulation driven by solar heating.

Define seasonality and describe how the tilt of Earth on its axis contributes to patterns of seasonality.

Seasonality refers to regular, predictable changes in climate through the year. Earth's 23.5° tilt causes different regions to receive varying sunlight throughout the year — producing the seasons. When the Northern Hemisphere tilts toward the Sun, it experiences summer, while the Southern Hemisphere experiences winter.

Explain why it can be 25°C in Vancouver and, at the same time, there is snow on the peaks of the North Shore mountains.

Temperature decreases with elevation because air at higher altitudes is thinner and holds less heat. As warm air rises, it expands and cools, causing mountain peaks to be much colder than sea-level regions nearby.

Describe and explain the global pattern of organization of terrestrial biomes.

Terrestrial biomes are organized by temperature and precipitation. Near the equator, tropical rainforests dominate where it's hot and wet. Moving toward the poles, decreasing temperature and moisture produce savannas, deserts, temperate forests, taiga (boreal forest), and tundra. These gradients are shaped by Earth's climate zones and air circulation.

What characteristics are used to classify aquatic biomes?

Aquatic biomes are classified by physical and chemical features such as salinity (freshwater or marine), light penetration (photic vs aphotic), depth, temperature, and nutrient availability. Examples include lakes, rivers, estuaries, coral reefs, and the open ocean.

Explain why the diversity of heterotrophic organisms varies among biomes.

Heterotroph diversity depends on primary productivity, temperature, and nutrient availability. Biomes with high plant productivity (like tropical rainforests or coral reefs) support more consumers, while low-productivity biomes (like deserts or the deep ocean) support fewer.

What is an ecotone?

An ecotone is a transition zone between two ecosystems or biomes where species from both habitats mix. These regions often have high biodiversity because they include species from both adjoining ecosystems and some unique to the boundary itself.