Title: Objective 5 Earth and Space Systems
1Objective 5Earth and Space Systems
- Middle School Science
- Science STAAR Need to Know
2Changes in the Earth over time
Weathering- the process of rocks being broken
down into smaller pieces.
3Two types of Weathering
- Mechanical
- Rocks break into smaller pieces by physical means
- Water, ice, wind, gravity, organisms changing
temperatures
- Chemical
- Rocks break into smaller pieces by chemical
reactions Air, water, acid salts react with
minerals in rocks to form new substances
4Erosion
Destructive
- The movement of particles from one location to
another is erosion - Weathered particles of rock are transported by
gravity, living organisms, water, glaciers wind.
5Deposition
Constructive
- The settling (depositing) of eroded particles as
sediments wherever they are transported by wind
or water.
6Sedimentary
Igneous
Metamorphic
7WHO Alfred Wegener
Proposed that Earths continent were all joined
in a single land mass called PANGAEA, which means
All land
8EVIDENCE
- Fossil Clues
- fossils of Messosaurus (dinosaur) found in South
America and in Africa. Lived in freshwater and on
land continents separated by salt water no
way it could swim from one to the other. - B. Glossopteris (plant) fossil found
in Africa, Australia, South America, and
Antarctica. - So many
- different areas
- and climates.
9Climatic Clues fossils of warm weather plants
found on island of Spitsbergen in Artic Ocean,
Evidence of Glaciers in temperate and tropical
areas
10Rock Clues similar rock structures found on
different continents showing similarities East
South America and West Africa coastlines have
same rock structure
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12Plate Tectonics
The force behind tectonic plate movement is
thought to be currents of magma flowing in
Earths mantle.
13Plate boundaries
- Tectonic plates slowly collide against one
another along plate boundaries. Sections of the
plates may break off and be pushed down, up, or
to the side. Mountain ranges, ocean trenches,
earthquakes volcanic activity are all common
along plate boundaries.
Pacific Plate is the largest
14San Andreas fault
15Topographic Maps
A map that shows the shape and elevation of the
land surface using contour lines , and shows
other land features using symbols and colors
16The most important thing to remember is that
CLOSE contour lines mean STEEP terrain and OPEN
contour lines mean FLATT terrain.
17Neap Tides occur during quarter moons, produce an
especially weak high tides
18Spring tides are especially high tides, occur
when Earth , sun and moon are lined up occur
during full and new moons
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20Four types of Fronts
21Warm Front when warm air advances into a region
of colder air warm air mass slides up and over
the cold air mass. Produces long period of steady
precipitation over a wide area. After front
passes the skies clear , wind direction changes
and temperature rises.
Cold Front occurs when cold air mass advances
and pushes under a warm air mass. Warm air is
forced up. Produces short periods of storms with
heavy precipitation. After front passes, winds
change direction, skies begin to clear and
temperature usually drops
22Stationary Front occurs where a warm air mass
and a cold air mass meet but neither advances.
Produces cloudiness and steady precipitation.
Occluded Front occurs when a fast-moving cold
front overtakes a slower moving warm front,
produces cloudy weather with precipitation
23High and Low Pressure
High Pressure - Winds blow outward, clock-wise
air pressure is highest at center usually bring
clear skies and fair, cool weather
Low Pressure Winds blow inward toward center,
counterclockwise air pressure is lowest at
center usually brings cloudy skies,
precipitation and warm weather
24THE SUN
Provides energy that drives convection in the
atmosphere and oceans which causes weather
Produces wind and ocean currents.
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26- All the land that drains into a specific body of
water. - Groundwater and surface water both contribute to
the water in a watershed. - Surface water becomes groundwater by soaking into
the sand and soil or by traveling through cracks
in rock.
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28Two important ways that oceans affect climate on
land
- Land heats up faster than water because land has
a lower specific heat than water does. This
causes the air over land to heat faster than the
air over water. The warm air rises, starting a
convection current that pulls air toward land
from the ocean. This keeps air over the land
from getting too hot and brings moist ocean air
inland. - Warm air holds more water vapor than cold air
does. When warm, moist air is cooled, clouds
form and can produce precipitation. This warm
air can be cooled by rising into the colder upper
atmosphere, by moving over cold ocean or lakes,
or by mixing with colder air. (Ex. Front
boundary- the edge where cool, dry air meets
warm, moist air. Often causes stormy weather)
29Nitrogen Cycle
Nitrogen changes back forth from nitrogen gas
to the nitrogen compounds used by plants
animals.
Nitrogen is passed from plants to other organisms
through food webs in the ecosystem. Once plants
animals use the nitrogen it returns to the
atmosphere as a gas, completing the cycle.
Some fertilizers contain nitrogen compounds
because plants need nitrogen to grow. Though
there is plenty of nitrogen gas in the
atmosphere, plants cant use this form. In
nature nitrogen can be changed from a gas to a
form that plants can use by lightning or by soil
bacteria and fungi in a process called nitrogen
fixation.
30Problems if too much Nitrogen in environment
31Carbon Cycle
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34Effects of carbon on environment
One of the biggest ways humans affect the carbon
cycle is by burning fossil fuels. Burning fossil
fuels transforms carbon into carbon dioxide.
Higher levels of carbon dioxide cause the
atmosphere to hold more heat energy. This may be
the cause of warmer temperatures measured in
recent years on Earth. (Called The Greenhouse
Effect) This could affect the climate in many
places. The kinds of plants and animals in these
climates may change if the warming continues.
35Without the carbon and nitrogen cycles, there
would be no life on earth!
36Catastrophic events affect the earth
Earthquakes
Floods
Meteorite crater
Volcanoes
37Ways humans affect the earth
- Two common forms of pollution
- Gases released into the atmosphere
- Chemicals that are carried by water into a
watershed
38Humans can cause extinctions
- Human can change
- The quality of the air, water soil we use
- Ecosystems by removing plants animals by
introducing new species, such as invasive plants
pets - Invasive species dont naturally live in the
ecosystem where they are introduced. - Invasive species compete with/or drive out native
species (species that live naturally in an
ecosystem)
FIRE ANTS- invasive species- accidentally
introduced to North America from South America.
They have few predators in NA aggressively
attack kill many kinds of native plants
animals. They have upset the balance of
ecosystems in many southern states.
39Eclipses
40Solar eclipse
When the moon is aligned so that its shadow falls
on Earths surface, the suns light is blocked
from reaching part of the Earth. Called solar
eclipse because its the sun that is being
blocked from our view.
41Lunar Eclipse
A lunar eclipse occurs when Earth blocks sunlight
from reaching the moon. This puts the moon in
Earths shadow.
424 main Phases of the Moon
43Moon phase diagram
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45Moons Revolution Rotation
46Seasons
Have you ever noticed that the sun travels lower
across the sky in winter than in summer? This
is because Earth is tilted on its axis at a 23.5o
angle.
During winter part of Earth tilts away from the
sun. This causes the suns rays to strike that
part of Earth at a lower angle than in the
summer.
47Seasons- Remember its the TILT of the Earth
that causes the seasons
48Winter Solstice- shortest day of the year
Days are shorter nights are longer during
winter. This occurs in December in the Northern
Hemisphere in June in the Southern
Hemisphere. Each hemisphere receives less
sunlight therefore less heat energy during the
winter. This is why temperatures are colder
during winter.
49Summer Solstice- longest day of the year
This occurs in June in the Northern Hemisphere
and in December in the Southern
Hemisphere. Earths revolution around the sun
causes part of the Earth to tilt toward the sun
at different times of the year. This causes that
part of the Earth to receive more sunlight at a
more direct angle. This is why days are longer
and nights are shorter.
50Equinox
Equinox- means Equal Night Daytime lasts
exactly as long as nighttime on the first day of
autumn the Autumnal Equinox (about September
21) and the first day of spring - the Vernal
Equinox (about March 21).
51The Sun Gravity
52The Sun is a Star
Our sun is a medium-size yellow star. In the
sun, hydrogen undergoes nuclear fusion, a process
that releases vast amounts of energy. During
fusion hydrogen atoms join to form helium atoms.
Hydrogen fusion is the source of light, heat, and
other radiation from the sun.
53Comets
Comets are made of various solids (like dirt
dust) and ice crystals. When their orbits take
them close to the sun, dust and ice heat up to
produce a tail behind the comet. Larger comets
may even become visible without the aid of a
telescope.
54Asteroids
Asteroids are rocky and usually follow regular
orbits around the sun. Asteroid belt- the
area between Mars and Jupiter that contains many
asteroids orbiting the sun.
55Nebulae
Nebulae are huge clouds of dust and gas. Some
scientists think that our solar system was formed
from nebula.
56Spiral
Irregular
Galaxies are groups of millions or billions of
stars. The galaxy we live in is the Milky Way
galaxy and has over 100 billion stars. It would
take 100,000 light years to travel across it!
Elliptical
57300,000,000 meters per second is the same as
300,000 kilometers per second. Thats the Speed
of Light!
58Light Speed!
59LIGHT YEAR - ly
Based on the speed of light and is a measure of
DISTANCE not TIME 9.5 X 10¹² Km/yr
60- Gravity is the force that governs motion of our
solar system.
61Closest star to Earth (besides the Sun)
Proxima Centauri is the nearest star to our Solar
System. Traveling at the speed of light, it
would take about 4 years 3 months to reach it
from Earth. (That makes it about 280,000 times
farther away from Earth than our sun!)
62H-R Diagram
In the Hertzsprung-Russell diagram each star is
represented by a dot. Stars are plotted by their
luminosity (brightness) and surface temperature.
63Hurricane
A huge, slowly-spinning tropical storm that forms
over water and has winds of at least 119 km/hr
(78 mph)
64Recipe to start development of a HURRICANE!!
- Water temperature 80 F or 26 C and up to 150
feet deep - Low Air Pressure
- High Moisture content
- Warm water mixes with warm air makes heat build
up quickly - Winds move into storm center from High Pressure
areas - Thunderstorms
65Hurricane Season
June 1st through November 30th
Hurricane Eye
Warm Temperatures, clear skies and calm conditions
Hurricane Movement
Atlantic ocean start in warm waters off west
coast of Africa and travel W/NW towards United
States
66- Hurricane Development
- Tropical Disturbance
- Tropical Depression
- Tropical Storm
- Hurricane