Transcript Meteorology

Meteorology:
Part 1
Earth Science
Golodolinski/Black
2009
Meteorology Vocabulary
Meterology
The study of the Earth’s atmospheric
changes
Weather
Meteorologist
A scientist who studies weather
Weather
Weather
Short term condition of the atmosphere
Can change very quickly, within days,
hours, or minutes
Weather is constantly changing, and it refers to
the state of the atmosphere at any given time
and place. Climate, however, is based on
observations of weather that have been
collected over many years. Climate helps
describe a place or region.
Composition of Atmosphere
Major component is air.
Air is a mixture of different
gases and particles, each
with its own physical
properties.
Volume of clean, dry air
Other components include:
water vapor, ozone,
Meteorology Vocabulary (continued)
 Atmosphere
The shell of gases surrounding Earth
Divided into layers based on temperature changes
with altitude
The 4 atmosphere layers are:
 Troposphere
 Stratosphere
 Mesosphere
 Thermosphere
Each layer is seperated by a “-pause”
In ESRT: “Selected Properties of Earth’s Atmosphere” p.
14
Thermal Structure of Atmosphere
ESRT: “Selected Properties of Earth’s
Atmosphere” p. 14
Part 1: Energy in Earth’s System
Internal Energy
Inside the Earth
Causes
Radioactive decay
Heat left over from the forming of Earth
Part 1: Energy in Earth’s System
 External Energy
 Solar energy from the
Sun
 Effected by
 Position of the sun is
in the sky
 The amount of solar
energy absorbed or
reflected by the
atmosphere
 How long the sun is
above the horizon
 Insolation
 Incoming solar radiation
ESRT: “Selected Properties of Earth’s
Atmosphere” p. 14
**Questions #1-4 p. 167**
ESRT: “Selected Properties of Earth’s
Atmosphere” p. 14
**Answers #1-4 p. 167**
*Questions #1-16 p. 168-9
How Energy Reaches Earth
 Radiation
Energy transfer in the form of electromagnetic
waves
Can travel through empty spaces in all directions
Most of the Sun’s energy that reaches Earth’s
surface is in the visible light range on the
Electromagnetic spectrum.
 The sun emits light and heat as well as the ultraviolet rays
that cause a suntan. These forms of energy are only part
of a large array of energy emitted by the sun, called the
electromagnetic spectrum.
Radiation
 All objects, at any temperature, emit
radiant energy.
Hotter objects radiate more total energy
per unit area than colder objects do.
 The hottest radiating bodies produce the
shortest wavelengths of maximum
radiation.
 Objects that are good absorbers of
radiation are good emitters as well.
What happens to solar radiation?

When radiation strikes an object, there
usually are three different results.
1. Some energy is absorbed by the object.
2. Substances such as water and air are
transparent to certain wavelengths of
radiation.
3. Some radiation may bounce off the object
without being absorbed or transmitted.
Solar Radiation
How Energy Reaches Earth
 Electromagnetic Spectrum
The classification of radiation based on wavelength,
frequency, and amplitude
ESRT p.14
Electromagnetic Spectrum
Visible Light Consists of an Array of
Colors
ESRT: Electromagnetic Spectrum
p.14
Questions #1-7 p. 170
ESRT: Electromagnetic Spectrum
p.14
Questions #1-7 p. 170
ESRT: Electromagnetic Spectrum
p.14
Answers #1-7 p. 170
ESRT: Electromagnetic Spectrum
p.14
Answers #1-7 p. 170
Questions #1-6 p. 170-1
How Energy Reaches Earth
 Angle of Insolation
 The altitude of the sun over the horizon, measured in
degrees
 Highest altitude is 90° (directly overhead)
 Changes depending on 3 things: time of day, latitude, season
Angle of Insolation Changes Depending
on 3 Things:
1. Time of day
 Sunrise
 Sun is lowest in the sky- cooler temperatures
 Solar noon
 Sun is highest in the sky- warmer temperatures
 Sunset
 Sun is low in the sky- cooler temperatures
Angle of Insolation Changes Depending
on 3 Things:
2. Latitude
The lower the latitutdethe higher the angle of
insolation
Equator= 0°; altitude of
sun is high all year,
warm temperatures
Poles= 90° (North and
South); altitude of sun is
low all year, colder
temperatures
Angle of Insolation Changes Depending
on 3 Things:
3. Season
Seasonal changes occur because
Earth’s position relative to the sun
continually changes as it travels
along its orbit.
In the northern hemisphere:
 Sun is highest in the sky in June:
 Warm temperatures
 Summer
 The summer solstice is on June
21; the “official” first day of
summer.
 Sun is lowest in the sky in
December:
 Cooler temperatures
 Winter
 The winter solstice is on
December 21; is the “official” first
day of winter.
Solstice
How Energy Reaches Earth
Duration of Insolation
The length of time the sun is over the
horizon
Depends on latitude and time of year
At the equator (0°): 12 hour days all year
long- no seasons
As the latitude increases…
Summer= Longer days- warmer temperatures
Winter= Shorter days- cooler temperatures
Questions #1-3 p. 173
Atmospheric Transparency
Atmospheric Transparency: Reflection/
Refraction/ Absorption of Insolation
Light vs. Dark
Atmospheric Transparency: Reflection/
Refraction/ Absorption of Insolation
Rough vs. Smooth
Atmospheric Transparency: Reflection/
Refraction/ Absorption of Insolation
Land vs. Water
Land heats up faster than water because
water has a higher specific heat
Land cools down faster than water, because
water has a higher specific heat
In the winter, the lake may not freeze
In the spring, part of the lake may still be
frozen even though the temperatures are
warm
Land vs. Water
Atmospheric Transparency: Reflection/
Refraction/ Absorption of Insolation
Specific Heat
The amount of heat (calories) needed to
raise the temperature of 1 gram of a
substance one degree Celsius.
ESRT p. 1
The higher the specific heat, the more heat
energy it requires to raise the temperature of the
material
The lower the specific heat, the faster it heats up
ESRT: Specific Heat p.1
ESRT: Specific Heat p.1
Questions a-e p. 175
ESRT: Specific Heat p.1
Answers a-e p. 175
Atmospheric Transparency
A good absorber of electromagnetic
energy is a good radiator of
electromagnetic energy. If a material
heats up quickly, it will also cool down
quickly.
Questions #1-5 p. 176
Terrestrial Radiation
Terrestrial Radiation
Radiation from Earth’s Surface
Infrared
Long wave radiation emitted from Earth’s
surface and other terrestrial objects
Terrestrial Radiation
Terrestrial Radiation
Greenhouse effect
Occurs as long wave radiation (infrared) is
trapped within Earth’s Atmosphere
Greenhouse gasses, such as carbon dioxide
and waver vapor, absorb the long wave
radiation
Traps in heat which causes Earth’s surface
temperatures to increase
 About 50 percent of the solar energy that
strikes the top of the atmosphere reaches
Earth’s surface and is absorbed.
Questions #1-9 p. 177-8
Terrestrial Radiation
 Conduction
Transfer of energy
from molecule to
molecule
Most effective in
solids, but can occur
in gasses or solids
Example
 Metal bar
Terrestrial Radiation
Convection
Energy transfer caused by the differences in
density
Occurs in fluids (liquid or gasses)
Most dominant heat transfer in Earth’s
Atmosphere
Warm air rises, cool air sinks
Questions #1-4 p. 179;
Section Review Questions #1-16 p. 180-2