Transcript tropical cyclone

EARTH AND SPACE SCIENCE
WHAT YOU
NEED TO KNOW
Explain how evidence from stars and other
celestial objects provide information about
the processes that cause changes in the
composition and scale of the physical
universe.
1.
2.
Describe that stars produce energy from nuclear reactions and
that processes in stars have led to the formation of all elements
beyond hydrogen and helium.
Describe the current scientific evidence that supports the theory
of the explosive expansion of the universe, the Big Bang, over 10
billion years ago.
STARS AND ELEMENTS
• Elements heavier than lithium are all synthesized in
•
•
stars. During the late stages of a star’s life cycle,
massive stars burn helium to carbon, oxygen, silicon,
sulfur, and iron.
Elements heavier than iron are produced in two ways: in
the outer envelopes of super-giant stars and in the
explosion of a supernovae. All these heavy elements are
produced in stars through nuclear fusion. All carbonbased life on Earth is literally composed of stardust. Most
of the material in our universe, however, is still
hydrogen.
Keep in mind that our Sun is a star and currently does,
and will continue to do, these things.
BIG BANG THEORY
• The Big Bang Theory is the dominant scientific theory about the
•
•
•
•
•
origin of the universe. According to the Big Bang, the universe was
created sometime between 10 billion and 20 billion years ago from a
cosmic explosion that hurled matter and in all directions.
There are three tests of the Big Bang theory (the expansion of the
universe, the abundance of light elements, and cosmic microwave
background radiation). These tests are supports for this theory.
The universe is expanding because galaxies can be observed moving
away from us at great speeds. There is a red shift in the light from
these.
Light elements, including H and He, make up the majority of
elements in the universe.
The Big Bang Theory received its strongest confirmation when the
cosmic radiation was discovered in 1964 by Arno Penzias and Robert
Wilson, who later won the Nobel Prize for this discovery.
Although the Big Bang Theory is widely accepted, it probably will
never be proved; consequentially, leaving a number of tough,
unanswered questions. Most theories will never be proved!
Explain that many processes occur
in patterns within the Earth’s
systems.
1. Explain the relationships of the oceans to the
2.
3.
lithosphere and atmosphere (e.g., transfer of energy,
ocean currents, and landforms).
Summarize the relationship between the climatic zone
and the resultant biomes.
Explain climate and weather patterns associated with
certain geographical locations and features (e.g.,
tornado alley, tropical hurricanes, and lake effect
snow).
EARTH AND CLIMATE
Global circulations explain how air and storm systems travel
over the Earth's surface. The global circulation would be
simple if the Earth did not rotate, if the rotation was not
tilted relative to the sun, and if Earth had no water.
The sun heats the entire Earth, but where the sun is more
directly overhead it heats the Earth and atmosphere more.
The result is that the equator becomes very hot with the
hot air rising into the upper atmosphere. That air would
then move toward the poles where it would become very
cold and sink, then return to the equator. One large area
of high pressure would be at each of the poles with a
large belt of low pressure around the equator. However,
since the earth rotates, since the axis is tilted, and since
there is more land mass in the northern hemisphere than
in the southern hemisphere, the actual global pattern is
much more complicated than this.
EARTH AND CLIMATE
Usually, fair and dry/hot
weather is associated with
high pressure, with rainy and
stormy weather is associated
with low pressure. You can
see the results of these
circulations on a globe.
Look at the number of deserts
located along the 30°N/S
latitude around the world.
Now, look at the region
between 50°-60° N/S
latitude. These areas,
especially the west coast of
continents, tend to have more
precipitation due to more
storms moving around the
earth at these latitudes.
CLIMATE AND BIOMES
Biomes are defined as "the world's major communities, classified
according to the predominant vegetation and characterized by
adaptations of organisms to that particular environment“.
The importance of biomes cannot be overestimated. Biomes have
changed and moved many times during the history of life on Earth.
More recently, human activities have drastically altered these
communities. Thus, conservation and preservation of biomes
should be a major concern to all.
The five biomes are
aquatic, tundra, forests,
deserts, and grasslands.
Think about what it
would be like to live in
each!
EARTH AND CLIMATE
• Tornado alley:
This is where
warm, humid air
from the Gulf of
Mexico collides
with cooler, drier
air from Canada.
These collisions
create the huge
thunderstorms
that can form
tornadoes.
EARTH AND CLIMATE
Tropical hurricanes: The terms "hurricane" and "typhoon" are other
names for a strong "tropical cyclone". Five factors are necessary
to possibly form tropical cyclones:
• Warm waters (or, more specifically, the moisture in the air above
them) are the energy source for tropical cyclones. When these
storms move over land or cooler areas of water, they weaken
rapidly.
• Upper level conditions must be conducive to thunderstorm
formation.
• A pre-existing weather disturbance. This is most frequently provided
by tropical waves—non-rotating areas of thunderstorms that move
through the world's tropical oceans.
• A distance of approximately 10 degrees or more from the equator,
so that the Coriolis effect is strong enough to initiate the cyclone's
rotation.
• Lack of vertical wind shear (change in wind velocity or direction over
height). High levels of wind shear can break apart the vertical
structure of a tropical cyclone.
EARTH AND CLIMATE
• Lake effect snow: Lake-generated snow squalls form
when cold air, passing for long distances over the
relatively warm waters of a large lake, picks up moisture
and heat and is then forced to drop the moisture in the
form of snow upon reaching the downwind shore. Lakeeffect snows are common over the Great Lakes region
because these large bodies of water can hold their
summer heat well into the winter, rarely freeze over, and
provide the long distance which allows the air to gain the
heat and moisture required to fuel the snow squalls.
Lake-effect snows are most
pronounced and effective
wherever terrain features
such as small hills or
mountains are oriented along
the lee shores. This is what it
would be like in Cleveland!
EARTH AND
CLIMATE
Moisture for storms comes
from large bodies of
water, primarily oceans,
and are pushed over the
continents by air
currents. When this
moist air comes over a
land and hits a
mountain, it is forced up
the range where it cools,
condenses, and often
falls as rain. Mountains
often receive much more
precipitation than the
areas around them.
As this air pushes over the top of the
mountain and down the other side, it
can again expand, although it has
now lost much of its moisture. This
"Rain Shadow" effect can be so
strong that the area behind a
mountain is a desert. In fact, all the
deserts of North America are
influenced by this "Rain Shadow"
effect.
Explain the 4.5 billion-year-history of Earth
and the 4 billion-year-history of life on Earth
based on observable scientific evidence in
the geologic record.
1. Explain that gravitational forces govern the
characteristics and movement patterns of the planets,
comets, and asteroids in the solar system.
2. Explain how geologic time can be estimated by multiple
methods (e.g., rock sequences, fossil correlation and
radiometric dating).
3. Describe how organisms on Earth contributed to the
dramatic change in oxygen content of Earth’s early
atmosphere.
SOLAR SYSTEM
• How does gravity work? There are two ideas you need to
know. These ideas work throughout the universe. The
more massive an object is, the more gravity it has. The
closer two objects are, the stronger the gravitational pull
between them. SO, putting these two rules together, the
more massive and the closer two objects are, the greater
the gravitational attraction between them. Think of
Newton when you think of gravity! Think of how early
scientists got in trouble for thinking the Sun, rather than
the Earth, was the center of our solar system!
Asteroids are rocky lumps of
material, sometimes known as
minor planets and exist mostly
between Mars and Jupiter. Comets
are a bit like giant dirty ice-balls
with diameters between five and
fifty kilometers. They, like the
planets, are kept in orbit by the
force of gravity.
GEOLOGIC TIME
• Fossil correlation – Fossils can often be used to
estimate dates of rocks in which they are embedded.
They can also be used to make guesses about what
earlier times were like (climate, etc).
• Radiometric dating – Rocks often contain
radioactive materials that are decaying at a constant
rate. Looking at the fractions of these materials now
present helps us date things. Carbon dating is a good
example.
Describe the finite nature of Earth’s
resources and those human activities that
can conserve or delete Earth’s resources.
• Use of resources
• Urban growth and waste disposal
• Farming (C and N cycles, erosion, crop
rotation, fertilizers)
• Pest control
• Global warming
• Exponential population growth
Explain the processes that move and shape
Earth’s surface.
•
•
•
Explain how the slow movement of material within
Earth results from:
a. thermal energy transfer (conduction and convection)
from the deep interior;
b. the action of gravitational forces on regions of
different density.
Explain the results of plate tectonic activity (e.g.,
magma generation, igneous intrusion, metamorphism,
volcanic action, earthquakes, faulting, and folding).
Explain sea-floor spreading and continental drift using
scientific evidence (e.g., fossil distributions, magnetic
reversals, and radiometric dating).
CONTINENTAL DRIFT
Wegener was intrigued (like people before
him) by plant and animal fossils found on the
matching coastlines of South America and
Africa, now widely separated by the Atlantic
Ocean. He reasoned that it was impossible
for most of these organisms to have swum or
have been transported across the ocean. To
him, the presence of identical fossil species
along the coastal parts of Africa and South
America was the best evidence that the two
continents were once joined.
His theory was also supported by the
discovery of both fossils of tropical plants
and dinosaurs in Antarctica that led him to
the conclusion that this now frozen land once
must have been situated closer to the equator
where lush, swampy vegetation could grow.
His downfall: HOW? WHAT FORCES?
EARTH’S STRUCTURE
In the picture,
you can see
the thin
crust, over
the mantle
and then the
core. Most of
the mantle
and core are
liquid and
can flow.
PLATE TECTONICS
What causes these plates
to move?
Since plates move, do
they run into each other?
The Earth’s crust is made up of
a dozen or so major plates
and several minor plates.
These tectonic plates are
constantly on the move. The
fastest plate races along at
15 centimeters (6 inches) per
year while the slowest plates
crawl at less than 2.5
centimeters (1 inch) per year.
You'll notice that most plates
are part continental and part
oceanic. Continental plates
tend to be made of lighter,
less dense rocks and oceanic
plates are made of heavier,
more dense rocks.
CONVERGENT BOUNDARIES
In a contest between a dense oceanic plate
and a less dense continental plate, it’s the
dense oceanic plate that sinks. In this case,
one plate is pulled beneath another
(subduction), forming a deep trench. The
long, narrow zone where the two plates
meet is called a subduction zone. Look for
curved volcanic mountain ranges with deep
trenches alongside. Boundaries like this
are known to produce historic earthquakes
of great magnitudes.
When two oceanic plates
collide, the plate that is older,
therefore colder and denser, is
the one that will sink.
MORE ON CONVERGENT
BOUNDARIES
• The Himalayan mountain
•
range provides a spectacular
example of continent vs.
continent collision. When two
continental plates meet headon, sometimes neither one
can sink because both plates
are too buoyant.
It is here that the highest
mountains in the world grow.
At these boundaries solid rock
is crumpled and faulted. Huge
slivers of rock, many
kilometers wide are thrust on
top of one another, forming a
towering mountain range.
Look at how older rocks that
are colder and denser may
now be layers under younger
rocks!
DIVERGENT BOUNDARIES
If plates collide, can
they also separate?
An example of divergent plate
boundaries is in East Africa
where a spreading process
has already torn Saudi Arabia
away from the rest of the
African continent, forming the
Red Sea. A new spreading
center may be developing
under Africa along the East
African Rift Zone.
Geologists believe that, if spreading
continues, the three plates that meet
at the edge of the present-day African
continent will separate completely,
allowing the Indian Ocean to flood the
area and making the easternmost
corner of Africa (the Horn of Africa) a
large island.
TRANSFORM PLATE BOUNDARIES
At transform plate boundaries plates grind
past each other side by side. Unlike
convergent or divergent boundaries, the
plates do not go under or over each other. A
good example of this type of boundary is the
one that separates the North American plate
from the Pacific plate along the San Andreas
fault, a famous transform plate boundary
that’s responsible for many of California’s
earthquakes. The San Andreas fault is
unusual because most transform boundaries
occur on the ocean floor.
Movement along the San Andreas (or any
other fault) can occur either in sudden jolts
or in a slow, steady motion called creep.
Which is a bigger problem for us here on
Earth?
CARTOON ACTIVITY
• Take your cartoon and place it in line with
the others so that the pictures tell a story.
This is very similar to how we take fossil
pieces and put them together to tell a
story about the past.