The Role of solar energy
The student will investigate and understand the role of
solar energy in driving most natural processes within
the atmosphere, the hydrosphere, and on the Earth’s
surface. Key concepts include
a) the Earth’s energy budget;
b) the role of radiation and convection in the
distribution of energy;
c) the motion of the atmosphere and the oceans;
d) cloud formation; and
e) the role of heat energy in weather-related phenomena
including thunderstorms and hurricanes.
- The Earth receives only a very small portion of the sun’s energy,
yet this energy is responsible for powering the motion of the
atmosphere, the oceans, and many processes at the Earth’s
- Solar radiation is made up of different types of radiation including
infrared, visible light, and
ultraviolet. (Know terms wavelength;
ultraviolet, visible, and
infrared radiation; and reflection and
- Incoming solar radiation is in
close balance with the energy that
leaves the atmosphere; otherwise the Earth would heat up or cool down.
(Analyze and interpret a chart or diagram showing the Earth’s energy
- Excess carbon dioxide and other gases may disrupt this
balance, creating a Greenhouse Effect. (Explain the Greenhouse Effect in
terms of the energy entering and leaving the atmosphere.)
- About one third of the sun’s incoming energy is reflected back out
to space. About one half of the energy striking the Earth is
the Earth’s surface.
convection distribute heat energy
around the globe
- The Earth’s surface is heated unequally.
- When air or water is heated, the molecules move faster and farther
apart, reducing their density, causing them to rise.
Cooler air or water
molecules move more slowly and are
denser than warm air or water. Warm
air or water rising coupled with cooler air or water descending forms a
cyclic rising/falling pattern called
- Radiation and convection
from the surface transfer heat energy. This
energy powers the global circulation of the atmosphere and the oceans on
our planet. (Students should analyze and explain how convection currents
occur, and how they distribute heat energy in the atmosphere and
The role of
in cloud formation
- As bodies of water (oceans, lakes, rivers, etc.) absorb heat energy,
the water evaporates forming clouds.
- Warm, moist air is
less dense than cold, dry air, so it
relative to colder, drier air. Warm, moist air rises and actually gives
off some heat as the moisture condenses.
- Clouds are not gaseous water
vapor; rather they are minute, condensed water particles. (order the
sequence of events that takes place in the formation of a cloud;
understand the role of heating and cooling in the formation of clouds.)
- Some thunderstorms are formed where the
land is strongly heated.
- Hurricanes form over
warm, tropical water and are fed by the energy of that water