WeatherSTEM Lesson
  • 9 of 19
    • 1: Title
    • 2: Objectives & Standards
    • 3: Essential Questions
    • 4: Sensor Sponsor
    • 5: Words To Know
    • 6: What is Solar Radiation?
    • 7: Weather Fusion - Solar Radiation
    • 8: What Influences Solar Radiation?
    • 9: Solar Radiation Influences
    • 10: Solar Radiation - Diffuse Measurements
    • 11: Solar Radiation - Direct Measurements
    • 12: Cosine Response
    • 13: Reasons to Measure Solar Radiation
    • 14: WeatherSTEM Fusion: UV Index
    • 15: UV Sensor
    • 16: Ultraviolet (UV) Exposure
    • 17: How to Avoid UV Exposure
    • 18: Key Points: Radiometers
    • 19: Evaluate Your Learning!
  • Prev
  • Next

Solar Radiation Influences

Source: Seagull J/Bigstock.com

Cloud Cover

Source: Veresovich/Bigstock.com

Solar Position

Source: Tatiana_Grozetskaya/Bigstock.com

Air Pollution

Cloud Cover

Because lower clouds are much thicker, much of the solar energy is reflected back into space so less solar energy reaches the Earth's surface. High, thin cirrus clouds in the Earth's atmosphere act in a way similar to clear air because they are highly transparent, allowing most of the solar radiation to pass through.

Solar Position

Places closest to the equator do not see much variation in the length of daylight hours during all four seasons. The number of daylight hours decreases in the northern hemisphere during the fall and winter due to the tilt of the Earth and distance from the equator. More solar radiation is present at midday, when the Sun is directly overhead, meaning the Sun’s rays have a shorter path to get to the surface of the Earth and the energy is not scattered.

Air Pollution

Different types of air pollutions (smog, smoke and volcanic ash) can limit the amount of solar radiation that reaches the Earth’s surface by up to 40%. More of the Sun’s direct light is scattered and have a larger impact on radiation coming in a direct line from the sun. In case of large volcanic eruptions, larger regions of the globe can experience decreased solar radiation for several months or years.

Copyright © 2017. WeatherSTEM. All Rights Reserved.