Download Atmosphere, Air Mass, Humidity, Severe Storms

AIR

Mixture of gases and particulates that are found
in the atmosphere
Two major gases are Nitrogen (70%) and Oxygen
(20%)
 Most other gases are found in varying amounts

Carbon dioxide is found in increasing amounts because of
human activities
 CO2 raises the temperatures in the atmosphere because of a
blanketing effect that traps the heat here near the surface
of the earth

LAYERS OF THE ATMOSPHERE





Exosphere This is really
space and contains very small
amounts of gases; temperatures
increase
Thermosphere Highest level
of the atmosphere where many
of our satellites and the
northern lights are found;
temperatures increase
Mesosphere Air begins to get
thicker and meteorites will
begin to burn up with friction;
temperatures decrease
Stratosphere Layer where
the ozone layer is found, along
with HALO jump flights and
military flights; Temperature
increases
Troposphere Layer that we
live in and the air is thickest
because gravity pulls it down,
all weather is located in this
layer; temperatures decrease as
you increase in altitude
TEMPERATURE

a measure of the warmth or
coldness of an object or
substance with reference to
some standard value


Most of the world uses Celsius as
a tool for measuring temperature;
Americans use Fahrenheit.
Temperatures have a great
effect on the biomes and
environments of the Earth

Can change them over long term
or short term changes
Example long term Plate tectonics
and Ice Ages
 Examples short term Volcanic
Eruptions and Storm Fronts

TEMPERATURE EFFECTS ON BIOMES
The amount of radiation
that the different parts of
the Earth receives creates
different zones on the
Earth that are created by
their temperatures
 The elevation changes
also affect the biomes
because the temperatures
change as you go further
up mountains and
plateaus

TEMPERATURE EFFECTS ON SEA LEVELS


Sea level has naturally
changed from changes
in plate movements and
global cooling and
warming trends
Since the Industrial
Revolution, there has
been a general increase
in sea level due to the
increased amounts of
carbon dioxide in the
atmosphere that keeps
heat near the surface of
the Earth and melts the
glaciers, adding to the
water found in the
oceans
HEAT TRANSFER ON EARTH

Heat on Earth is transferred in 3 ways

Conduction
Heat transfer through direct contact of an object
 Examples: Hand touching a hot pan, lava touching a forest,
hot iron on hair/clothes


Convection
Heat transfer through the
circulation of heat
 Examples: Mantle convection,
air and water currents, convection oven

HEAT TRANSFER ON EARTH

Radiation
Heat transfer through which
heat travels by waves
through an empty space
 3 types of ways that radiant
energy will react when it
comes to Earth
 1. Absorption Heat is
taken in by an object
 2. Reflection  Heat is
bounced off a reflective
surface (water, glass)
 3. Scattering  Heat hits
an object and is thrown in
random directions

TEMPERATURE AND AIR PRESSURE

Since warm air rises and cool air sinks, there is a
difference in the amount of air that is located in
certain parts of the atmosphere

That means that there is different amounts of air
pressing down on us

This pressing down of air on us is called air pressure

Air Pressure  The total amount of air that is
exerted on us
We are being pushed in all directions by the air that
surrounds us
 The amount of pressure can be measured using a tool
known as a barometer

DIFFERENCE IN AIR PRESSURES

Is what gives us winds
 All things in nature want to move to some sort
of balance, so areas that have high amounts of
air pressure will move to areas of low air
pressure
 When this movement happens, it will bring
with it any moisture and temperature
differences that it was experiencing in the
areas of high pressure
 Wind could bring bad or good conditions to a
new area
DIRECTION OF THE WINDS

Are characterized by the differences in air
pressure and the Coriolis Effect
In the Northern Hemisphere Clockwise
 In the Southern Hemisphere  Counterclockwise

AREAS WHERE THE AIR PRESSURES ARE THE
HIGHEST AND LOWEST WILL CREATE
PRESSURE CENTERS

1. Low Pressure Center
 a. AKA Cyclone
 b. The lowest pressures in this system will be
in the center of this area and the highest will
be on the outside parts of this area, meaning
that winds will blow from the outside to the
center of these systems
 c. These will spin counterclockwise in the
Northern Hemisphere
 d. These pressure systems will bring most of
the storms, because the gathering of the
moisture from the inward moving air collects
and condenses the moisture to form clouds

2. High Pressure Center
 a. AKA Anticyclone
 b. The highest pressure will be on the
inside and the lowest pressures will
be on the outside meaning that wind
will blow from the inside to the
outside
 c. They will spin clockwise in the
Northern Hemisphere
 d. These pressure centers will more
and likely be accompanied by fair
weather because the outward moving
air separate moisture and does not
encourage condensation into clouds.

Lines on this map are called isobars and they
help us to tell where weather will move to and
how fast the winds may be in a particular area.
 When isobars are close together, much like
contour lines, you will have faster winds in
that area because the air pressure will try to
balance out quickly
 When isobars are far apart, you will have more
of a gentle breeze
 Weather and winds will travel southeast on
this map because winds will take them with it
to the areas of low pressure
AIR IS NOT JUST AIR WHEN IT COMES TO
WEATHER

When pressure systems move the air across the
country, they will combine large bodies of air
known as air masses
When air mass first form, they take on the
characteristics of the area that they form over (source
region)
 Air masses are named by the two main
characteristics of moisture content and temperature

CHARACTERISTICS OF AIR MASSES

1. If an air mass forms over water, it will draw
water vapor into the air, making the air more
moist

This air will have a high humidity



Humidity is the total amount of water vapor in the air
This type of air mass is called Maritime
2. If an air mass forms over land, it will not draw
as much moisture from the land, so the air is
drier
This air will have a low humidity
 This type of air mass is called Continental


*** You CANNOT have moist and dry air at the
same time, so can an air mass be named
continental maritime? ________****
CHARACTERISTICS OF AIR MASSES

3. If an air mass forms far from the equator, the
air does not receive as much solar radiation, the
temperature of the air is colder


4. If an air mass forms closer to the equator, the
air receives more solar radiation, the
temperature of the air is warmer


This type of air mass is called polar
This type of air mass is called tropical
*** You CANNOT have hot and cold air at the
same time, so can an air mass be named Polar
Tropical? ___________***
TYPES OF AIR MASSES


mP  maritime Polar
 Moisture Content? wet
 Temperature? cold
 Location where it
could form over?
North Atlantic Ocean/
North Pacific Ocean
mT  maritime Tropical
 Moisture Content? wet
 Temperature?
Warm/hot
 Location where it
could form over? Gulf
of Mexico/South
Atlantic and Pacific
Ocean
TYPES OF AIR MASSES


cP  continental Polar
 Moisture Content? dry
 Temperature? cold
 Location where it
could form over?
Canada/ Northern
United States
cT  continental Tropical
 Moisture Content? dry
 Temperature?
Warm/hot
 Location where it
could form over?
Mexico/ Southern
United States

**** When an air mass moves, its characteristics
will change as its moves to areas of different
temperatures and humidity.****
EX. If a maritime Polar air mass moves from the
Northern Pacific Ocean to Canada, what type of air
mass will it become? continental Polar
 If a continental Tropical air mass moves from Texas
to Minnesota, what type of air mass will it become?
continental Polar

FRONTS

Air mass themselves will not make weather and
storms form. It is when the air masses combine
that you will have a mixing of different
temperatures that will cause clouds to form.

The boundaries that form between different air
masses is known as fronts
TYPES OF FRONTS

1. Warm Front
When a warm air mass moves into an area that has
colder temperatures, the warm air will rise and
condensation will slowly form clouds
 Weather for this type of front is light to moderate
precipitation for long periods of time
 There will be an increase in temperatures as the
warm air moves in
 Symbol:

WARM FRONT DIAGRAM
TYPES OF FRONTS

2. Cold Front
When a cold air mass moves into areas that has
warmer temperatures, the cooler air pushes the
warm air up rapidly and causes the clouds to form
rapidly as well.
 The clouds rise high in the air and form the stronger
storms like tornadoes, hurricanes, and
thunderstorms.


These towering clouds are called cumulonimbus
Weather for this type of front is heavy precipitation
and gusty winds, but they will clear quickly
 There will be a decrease in temperatures as the cold
air moves in
 Symbol:

COLD FRONT DIAGRAM
TYPES OF FRONTS

3. Stationary Front

When neither a cold or warm air mass is strong
enough to move the other one around, this type of
front forms and remains until some other air mass or
pressure system moves the air around.

This could change into a cold or warm front later
Usually cloudy, prolonged precipitation and storm
trains are found there
 Symbol:

STATIONARY FRONT DIAGRAM
TYPES OF FRONTS

4. Occluded Front
When two cold air masses converge on opposite sides
of a warm air mass, they both push together and the
warm air rises rapidly
 This rapid ascension of warm air causes fast rates of
precipitation
 Short bursts of storms and heavy rain will happen
until the humidity drops and the air is left feeling
very light
 Symbol:

OCCLUDED FRONT DIAGRAM
HUMIDITY
is the amount of water vapor in the air. It is kind
of a hard number to find because the air is
always flowing and circulating so the number is
never constant.
 Relative Humidity is the amount of water vapor
that is in the air now compared to the amount of
water vapor that air can hold all together. The
formula for this is:
Amount of water vapor in the air
Total amount of water vapor the air can hold

RELATIVE HUMIDITY
This number is then told in a percentage for us to
then read and interpret how moist the air is.
 When the air temperature drops, and the
humidity is high, the air reaches dew point, when
water will condensate out of the air and form
water droplets on objects outside.
 With this chart below, we can find the relative
humidity of an area using the dry air
temperature of the area (dry bulb) and the
temperature of the water vapor in the air (wet
bulb). We use a tool known as a psychrometer to
find both of these temperatures at the same time.

SEVERE STORM TYPES 
THUNDERSTORMS

Thunderstorms Large cumulonimbus
clouds that have lightning and thunder that
occur within and around the cloud
How do they form?
 1. When warm air is lifted, the moisture in the air
cools and condenses
 2. Water droplets in the clouds continue to condense
larger and build
 3. When the droplets are too heavy, they fall to the
ground as rain

SEVERE STORM TYPES 
THUNDERSTORMS
4. When the droplets break up in the cloud, they
become electrically charged, with different parts of
the cloud become positively and negatively charged
 5. The charge is attracted to opposite charges on the
surface of the Earth, and as the air broken around
that charge, you get the rumbles of thunder


Most thunderstorms in North Carolina happen in the
spring and summer months
SEVERE STORM TYPES 
THUNDERSTORMS

What are the effects of a thunderstorm?
Heavy rains will increase the watertable and a loosening of
the soils and lightning strikes could start forest fires which
leads to habitat alteration
 On average, 93 to 223 deaths happen annually nationwide
in the US

SEVERE STORM TYPES  TORNADOES

Tornadoes The result of a supercell
thunderstorm that have rains and high velocity
wind speeds.

How do they form?
1. A change in wind direction and speed within the
thunderstorm itself
 2. This change happens high in the cloud and creates an
invisible circulating affect in the atmosphere
 3. Rising air will spiral in the thunderstorm and the
rotating winds drop and lower a wall of clouds to the ground
 4. Once the touchdown occurs, the energy of the storm will
continue until the air in the cloud cools and the tornado, in
essence, dies.

SEVERE STORM TYPES  TORNADOES

What are the effects of a tornado?
Rains, severe winds, lightning, or flash floods (if the
tornado happens near water)
 Because of the winds in a tornado, the cross winds
can tear apart any structure that is not built in the
ground or lower to the ground
 When gas lines or electrical lines are caught by these
winds, they can destroy homes and towns because of
responders unable to get through rubble and chaos

SEVERE STORM TYPES  TORNADOES
Most tornadoes in the US happen in Tornado
Alley which is the Midwest section of the US
(Kansas, Oklahoma, Texas)
 Peak months for tornadoes are March through
May in the southern US
 75 % of the world’s tornadoes happen in the US
 On the enhanced Fujita, the scale upon which
tornadoes are measured, strength of a tornado is
based on the amount of destruction it causes and
not the wind speed
 Tornadoes generally only last for a few minutes

SEVERE STORM TYPES  HURRICANES

Hurricanes Large thunderstorm storms that
start in the Atlantic or Pacific Ocean near the
equator
How do they form?
 1. Moisture from the oceans evaporates and rises into
the air and builds a thunderstorm
 2. As that hot, humid air rises further, circulating air
begins twist the air and increases the moisture and
the winds
 3. The continuing evaporation adds more water vapor
to the atmosphere; the thunderstorm builds and
builds into a topical storm
 4. Eventually, the tropical storm has some much
energy and spinning winds that it is then classified
as a hurricane

SEVERE STORM TYPES  HURRICANES

What are the effects of a hurricane?
Storms surges (a wall of ocean water that is pushed
up and out by the hurricane will flood areas of the
coast
 High winds and shifting winds take out many power
lines, vegetation, and any structures that are not
cemented deep into the ground

SEVERE STORM TYPES  HURRICANES
Typical season for hurricanes in the US is from
late summer to early autumn because by then
the water is warm enough to evaporate readily
 The Saffir-Simpson scale is the measurement tool
for determining how big a hurricane is based
again on its level of destruction
 In the Pacific Ocean, hurricanes are called
typhoons in order to give people a better idea of
where they formed
 Hurricanes can last up to a week from the
moment they form to the moment they “die”
 Hurricanes will lose their energy for two reasons:
 1. Friction with the land
 2. Loss of water evaporated water (energy source)

CLIMATE

The accumulation of temperature and weather
patterns in a certain location over a long period
of time
FACTORS THAT CAN AFFECT CLIMATES
WORLDWIDE

1. Latitude  As latitude increases (meaning
that you are getting closer to the poles), the
intensity of the sun’s rays decreases (means that
there is less sun reaching these places.)
Near the Poles Less radiation, cooler temperatures
 Near the Equator  more radiation, warmer
temperatures


2. Altitude The higher you go in altitude, the
colder it gets

Mountains are colder climates than plains and
valleys
FACTORS THAT CAN AFFECT CLIMATES
WORLDWIDE
3. Topography Depending on which side of
mountains you are on, you may receive more or
less precipitation due to the fact that
precipitation will run dry as it passes over
mountain ranges
 4. Water Bodies  Areas that are downwind of
large bodies of water will have cooler
temperatures because of the affect that water
takes longer to heat

FACTORS THAT CAN AFFECT CLIMATES
WORLDWIDE
5. Global Winds  The amount of circulation
around an area can distribute the heat and
moisture differently around the global
 6. Vegetation  This affects how much sun is
absorbed and how quickly moisture can be
released in the form of water vapor

ALL CLIMATES AROUND THE WORLD HAVE
BEEN CLASSIFIED INTO 5 MAJOR CLIMATE
GROUPS UNDER THE KOPPEN CLIMATE
CLASSIFICATION

1. Humid Tropical Climates
These climates have no winters, have an average
temperature of 18 ºC, and an annual rainfall of about
200 cm or more
 Examples Tropical Rainforest and Savannas (Africa
and South America)


2. Mid Latitude Climates
These climate can have mild or severe winters,
temperatures that are on average 18 ºC to above
-3 ºC, and can either have a high precipitation rate
in the winter or in the summer.
 Examples Mostly cover the US and Northern Eurasia


3. Dry Climates
Not really having a temperature range, this climate
is more defined by the amount of precipitation that it
receives annually, which is very little
 Examples Steppe or Deserts (Gobi, Sahara, Arabian)


4. Polar Climates
This climates warmest months are below 10 ºC, has
periods of perpetual night (no sunlight at all during
the day) and very little solar radiation
 Examples Tundra (Greenland and Antarctica)


5. Highland Climates
Very localized and small, these climates are usually
cooler and wetter than those areas that are at lower
elevations nearby.
 Examples Mid China, British Columbia, Canada

WE ALL KNOW THAT RAISED AMOUNTS OF CO2 PUT OUT MY
HUMANS CAN INFLUENCE THE CLIMATES OF THE WORLD, BUT
THERE ARE SEVERAL NATURAL PROCESSES THAT CAN EFFECT
CHANGE IN THEM TOO

1. Volcanic Eruptions

Large amounts of ash and dust can reflect some of
the solar radiation back into space and cool
temperatures here on Earth

2. Ocean Circulation

Warmer than usual ocean temperatures can create a
short term change in climates (El Nino)
El Nino is when climates around the world are wetter and
warmer, especially in the US
 La Nina is when the climates around the world are drier
and cooler, creating massive droughts


3. Solar Activity

Dark spots on the sun called sunspots occur at times
of high solar activity and corresponds with warmer
temperatures in Earth’s history

4. Earth Motions
Plates diverging and converging can change the
amount of land and water exposed, creating different
climates all the time
 Earth’s orbit has moved us closer and farther from
the Sun at times over the last 4 by, changing climates
by increased and decreased amounts of solar
radiation

GREENHOUSE EFFECT
Natural Heating of the Earth’s atmosphere from
the retention of heat
 We need to retain some of the heat from the core
and solar radiation in order for life to continue on
this planet
 The effect is created by several gases that hold
this heat near the surface


Examples: Water vapor, Carbon Dioxide, Methane,
Nitrous Oxide, and Ozone
OZONE

Ozone can have both good and bad effects
Good ozone is found in the stratosphere and protects
us from high amounts of solar radiation
 It is made by the splitting of oxygen, where it is then
added to another oxygen atom
 Many countries all over the world are trying to
protect the ozone layer, but some countries burn
chemicals or have chemicals factories going that can
deplete the ozone, though not always in their areas

OZONE
Bad ozone is found in the troposphere where we and
are exposed to it.
 Bad ozone, when we are exposed to it, can cause
upper respiratory problems, along with other skin
diseases with prolonged exposure
 Made when coal and gasoline is burned in the
process of combustion
 Everyone is exposed to bad ozone, but some people
are more susceptible to the health risk of ozone
exposure

Babies and Toddlers (weak immune systems)
 Elderly (weak immune systems)
 City Dwellers (People in the city are more exposed because
of the close conditions to each other and the higher
percentage of transportation running)

RESULTS OF GREENHOUSE EFFECT

> With the increasing amount of burnt fossil
fuels, we are increasing the amount of
greenhouse gases, which means that we are
increasing the amount of heat that is kept near
the surface. This leads to global warming.
GLOBAL WARMING
The unnatural heating of the Earth’s atmosphere
 This can be caused by nature at an accelerated
pace or by human activities (which is the
prevailing theory at this time)
 Causes of Global Warming in this age

1. Burning of fossil fuels (gasoline, oil, coal,
petroleum)
 2. Release of aerosols into the atmosphere from any
type of spray can (hair spray, air fresheners, cleaning
supplies)
 3. Deforestation (there is not enough plants taking in
the extra carbon dioxide that is flowing into the
atmosphere)

GLOBAL WARMING

Effects of Global Warming





1. There is an increase in temperatures around the
globe
2. The climates will begin to change because with a
change in temperature, that means that climate
conditions will change as well
3. Glaciers will begin to melt because of the increase
in global temperatures, meaning that there will
smaller cooling centers for the world
4. With the glacial melt, there will be a rise in sea
level, which may help to cool the Earth, but that
would lead to further problems for the human race
5. Higher oceans means that anyone that is located
on the lower coastal areas may be flooded out of their
homes. This means problems for business, docks and
transportations, and property damage to all
UNNATURAL CAUSES OF CLIMATE
CHANGE

Heat Islands As urban areas develop,
changes occur in their landscape.
Buildings, roads, and other infrastructure replace
open land and forests
 Surfaces that were once permeable and moist become
impermeable and dry
 These changes cause urban regions to become
warmer than their rural surroundings, forming an
"island" of higher temperatures in the landscape.
 How is this going to change the climate of an area?
The city will have higher temperatures and less
precipitation because of all of the concrete jungle

UNNATURAL CAUSES OF CLIMATE
CHANGE

Deforestation Forests play a huge role in the
warming cycle on our planet.
When forests are cut down, not only does carbon
absorption decrease, but also the carbon stored in the
trees is released into the atmosphere as CO2 if the
wood is burned or even if it is left to rot after the
deforestation process.
 If we carry on cutting down the main tool we have to
reduce this CO2 build up, we can expect the climate
of our planet to change dramatically over the next
decades
 How is this going to change the climate of an area?
The increased amount of CO2 will cause the
increase in temperatures and precipitation that is
associated with global warming

UNNATURAL CAUSES OF CLIMATE
CHANGE

Ocean Acidification Oceans absorb quite a
bit of carbon dioxide from the atmosphere
With the increased amount of CO2 in the air, the
oceans cannot absorb any more than it can hold
 Too much CO2 in the ocean will cause the shells of
clams and the coral reefs to be fragile and not
support the life that exist in and around it
 Sea life will not be able to adapt to the changing
environment that will grow acidic because of the
rising amount of CO2 in the oceans
