1 Earth Science
E.12.A.1 http://www.rpdp.net/sciencetips_v2/E12A1.html
What is the primary energy source behind
the water cycle?
A. Earth’s internal energy
B. Sun’s electromagnetic radiation
C. Moon’s gravitational attraction
D. Radioactive decay of elements
Southern Nevada Regional Professional Development Program
K-12 Science
2 Earth Science
E.12.A.1 http://www.rpdp.net/sciencetips_v2/E12A1.html
Which of the following is not a contributing factor to
the uneven warming of Earth’s surface?
A. Different surfaces warm at different rates.
B. Different surfaces retain energy differently.
C. The Sun is farther from Earth during winter.
D. The Sun’s rays hit the surface at varied angles.
Southern Nevada Regional Professional Development Program
K-12 Science
3 Earth Science
E.12.A.2 http://www.rpdp.net/sciencetips_v2/E12A2.html
Cyanobacteria first appeared in Earth’s oceans over 2
billion years ago and were extremely abundant by 545
million years ago.
Cyanobacteria affected Earth’s atmosphere by
A. rapidly increasing carbon dioxide levels in the
atmosphere.
B. gradually adding to the amount of oxygen in the
atmosphere.
C. slowly consuming all the ozone from the
atmosphere.
D. progressively using up the nitrogen in the
atmosphere.
Southern Nevada Regional Professional Development Program
K-12 Science
Principles of Science
Mr. Porter
How Clouds Form
1.) The sun’s heat causes water to
evaporate, or change to a gas.
A.) This gas, water vapor, becomes
part of the air.
2.) As the air is heated, it becomes
less dense and rises taking the water
vapor with it.
How Clouds Form
3.) As the air rises, it cools (loses
heat) and the water vapor
condenses, turns to liquid water,
on dust particles.
A.) The water droplet are so tiny
they stay in the air and make
clouds.
How Clouds Form
Precipitation
4.) If the water droplets get large
enough, they fall to the ground as
precipitation.
-Examples:
Rain, Sleet, Snow, or Hail
Precipitation (Hail)
Cloud Formation
Wind
Defined as “moving air”.
Caused by unequal heating of the
Earth due to radiation from the sun.
When warm air rises, cooler air
flows in to take its place.
The new air is then warmed and
rises.
Wind
Greenhouse Effect
Greenhouse Effect
Gases in the atmosphere capture
heat from the sun that is radiated,
or comes from the Earth.
Greenhouse Effect
1) The sun emits rays that heat the Earth.


Some rays bounce off the atmosphere
back into space.
Some rays make it to the surface and
warm our planet.
2) This warming is one reason Earth can
support life.
Greenhouse Effect
Greenhouse Effect
3) The Earth radiates the sun’s energy
back in the form of heat (infrared
radiation).

Some rays go to space
4) Some rays are absorbed by
greenhouse gases such as carbon
dioxide (CO2) that hold in more
heat.
Greenhouse Effect
Global Warming - The increase
of the Earth's atmospheric
and oceanic temperatures
Global warming due to an increased
greenhouse effect has
ABSOLUTELY NOTHING TO DO
WITH THE “O-ZONE” LAYER!!!
The “O-Zone” layer is a part of the
Earth’s atmosphere that acts as a filter
which reduces the amount of the sun’s
UV rays that reach our planet.
 The greenhouse effect is the warmth
that the atmosphere traps for our planet
due to CO2 and other gases that trap
infrared radiation.

Global Warming - Causes
1) Deforestation – removal of large
numbers of trees, plants, and
other vegetation that absorb CO2.

This causes an excess of CO2 in the
atmosphere.
Global Warming
Global Warming - Causes
2) Fossil Fuels – Gasoline (made
from petroleum) being used by
automobiles and other types of
transportation, as well as
polluting factories, also contribute
to excess CO2 in the atmosphere.
Greenhouse Effect
Homework Questions
1) What causes air to move?
2) List 4 examples of precipitation.
3) Why is the Earth’s atmosphere compared
to a “greenhouse”?
4) Is the Greenhouse Effect good or bad for
our planet. Explain.
5) How can someone get sun-burned when
it’s cloudy outside, or sit in a steam room
and not get a tan? (Hint: o-zone and
greenhouse effect).
5 Earth Science
E.12.A.3 http://www.rpdp.net/sciencetips_v2/E12A3.htm
The two most abundant greenhouse gases in
Earth’s atmosphere are
A. water vapor (H2O) and carbon dioxide (CO2).
B. carbon dioxide (CO2) and methane (CH4).
C. ozone (O3) and carbon monoxide (CO).
D. nitrogen (N2) and oxygen (O2).
Southern Nevada Regional Professional Development Program
K-12 Science
6 Earth Science
E.12.A.3 http://www.rpdp.net/sciencetips_v2/E12A3.htm
Greenhouse gases help keep Earth at a habitable
temperature by
A. blocking the cold winds and ices originating in
outer space.
B. serving as essential nutrients for atmospheric
phytoplankton.
C. allowing only infrared light to reach Earth’s
surface.
D. retaining some of the Sun’s energy in our lower
atmosphere.
Southern Nevada Regional Professional Development Program
K-12 Science
7 Earth Science
E.12.A.4 http://www.rpdp.net/sciencetips_v2/E12A4.htm
Over the next century, the temperature in the Great Basin Desert is
expected to increase anywhere from 2 to 5 degrees Celsius due to
global climate change.
Which statement best explains how the movement of heat will likely be affected
in the Great Basin Desert due to global climate change?
A. Radiation will transfer more heat from the desert’s floor to Earth’s
atmosphere and conduction will move more heat out of Earth’s atmosphere
into space.
B. Conduction will move more heat from Earth’s surface to the atmosphere and
radiation will move more heat around in the atmosphere.
C. Radiation will transfer the same amount of heat from the sun to Earth’s
surface and more heat will be moved around in the atmosphere via
convection.
D. Conduction will transfer the same amount of heat from the sun to Earth’s
surface and more heat will move through the desert’s floor via radiation.
Southern Nevada Regional Professional Development Program
K-12 Science
From http://nde.doe.nv.gov/Assessment_HSPE.htm