fv7 - solar radiation

AP Environmental Science: Unit 4 – Earth Systems & Resources

Topic: 4.7 Solar Radiation and Earth's Seasons

Main Source of Energy

  • Solar Radiation

    • The sun is the primary energy source for Earth.

    • Affects seasonal changes in light and temperature.

Seasonal Changes

  • Length of Daylight

    • Varies with seasons; longer days in summer, shorter in winter.

  • Sun's Angle

    • In winter, the sun's angle is less favorable, resulting in longer nights and less solar radiation.

    • In summer, the sun's angle is more direct, leading to shorter nights and more solar radiation.

Latitude's Role

  • Solar Radiation Reception

    • At the equator (0° latitude), solar radiation hits directly, resulting in higher intensity.

    • Higher and lower latitudes experience curvature, spreading solar radiation over a larger area, leading to lower intensity.

Earth's Tilt and Orbit

  • Seasons and Temperature

    • Earth's tilt towards the sun results in longer days and higher temperatures.

    • Tilt away from the sun leads to longer nights and cooler temperatures.

  • Equinoxes

    • Occur during spring and fall when the tilt changes, marking transitions between seasons.

    • Day and night lengths are approximately equal.

Key Terms

  • Biomes

    • Large ecological communities with distinct climate, vegetation, and animal species.

  • Equinoxes

    • Two points in Earth's orbit when day and night are nearly equal, marking the start of spring and autumn.

  • Solstices

    • Points in the year when the sun reaches its highest or lowest point, resulting in the longest and shortest days.

    • Summer Solstice: Around June 21, marks the start of summer.

    • Winter Solstice: Around December 21, marks the start of winter.

Effects of Earth's Curvature

  • Distribution of Solar Radiation

    • Solar radiation is not evenly distributed due to Earth's curvature.

    • Lower latitudes receive more intense solar radiation.

    • Higher latitudes receive less intense solar radiation due to the oblique angle of sunlight.

Summary

  • Understanding solar radiation and its effects on Earth's seasons is crucial for comprehending climate patterns and ecological systems. The interplay between Earth's tilt, orbit, and latitude significantly influences temperature and daylight variations throughout