Why is it generally warmer near the equator and colder near the poles?
AThe equator is closer to the Sun than the poles are
BSunlight hits the equator at a direct angle, concentrating energy on a smaller area, while sunlight hits the poles at a low angle, spreading energy over a larger area
CThe equator has more volcanoes that heat the surface
DThe poles are covered in ice, which blocks the Sun's heat
The curved shape of Earth means sunlight hits the equator nearly straight on (direct angle), concentrating solar energy on a relatively small area. Near the poles, the same amount of sunlight strikes at a low, glancing angle and is spread over a much larger area, delivering less energy per unit of surface. This geometric effect is the primary reason for Earth's temperature gradient from equator to poles.
Question 2 Short Answer
Name the three main climate zones and briefly describe each.
Think about your answer, then reveal below.
Model answer: Tropical (near the equator, roughly 0-23.5 degrees latitude) — warm to hot year-round with high precipitation in many areas. Temperate (mid-latitudes, roughly 23.5-66.5 degrees) — distinct seasons with warm summers and cool to cold winters. Polar (near the poles, above about 66.5 degrees) — cold year-round with very low precipitation, often covered in ice and snow.
These zones are determined primarily by the angle at which sunlight hits the surface, which is controlled by latitude. Local factors like altitude, ocean currents, and distance from the coast create important variations within each zone.
Question 3 True / False
Most tropical areas are wet and covered in rainforest.
TTrue
FFalse
Answer: False
While many tropical areas receive heavy rainfall (tropical rainforests), the tropical zone also includes some of Earth's driest deserts. The Sahara Desert, for example, is near the Tropic of Cancer. The tropical zone is defined by temperature (warm year-round), not by precipitation. Global atmospheric circulation patterns create both wet tropical regions (near the equator where air rises) and dry tropical regions (around 30 degrees latitude where air sinks).