Science Flashcards
1
Q
What is a day?
A
The time it takes a planet to complete one full rotation on its axis
2
Q
What is a rotation?
A
the spinning of a body, such as a planet, on its axis
3
Q
What is daytime?
A
The half of the earth that faces the sun
4
Q
What is nighttime?
A
The half of the earth that faces away from the sun
5
Q
How long does it take for Earth to complete one rotation on its axis?
A
24 hrs
6
Q
What is a revolution?
A
The motion of a body that travels around another body in space
7
Q
How long is one full revolution of Earth around the sun?
A
365 days (1 year)
8
Q
What does the Earth’s axis always point toward as it revolves around the sun?
A
Toward the North Star,
Tilt 23.5 degrees (never changes)
9
Q
About how many hours of light do all locations on Earth experience per day?
A
an average of 12 hours of light a day. (It can vary)
10
Q
What is the midnight sun?
A
Areas north of the Arctic Circle that have 24 hours of daylight
11
Q
What is polar night?
A
Areas south of the Antarctic Circle that receive 24 hours of darkness
12
Q
What is a season?
A
the changes in the intensity of temperature and the number of daylight hours as Earth revolves around the sun. Both the tilt of Earth’s axis and Earth’s spherical shape play a role in Earth’s changing season
13
Q
What is an equinox?
A
When sunlight shines equally on the Northern and Southern Hemispheres. Half of each hemisphere is lit, and half is in darkness
14
Q
What is a solstice?
A
the area of sunlight at a maximum in one hemisphere and at a minimum in the other hemisphere
15
Q
What is the September Equinox?
A
September 22 or 23, marks the beginning of fall in the Northern Hemisphere. When Earth is in this position, sunlight shines equally on both poles, about 12 hours.
16
Q
What is the December Solstice?
A
December 21 or 22, the North Pole is tilted to the farthest point away from the sun and the South Pole is in complete sunlight (axis is the same). Marks the start of Winter in the Northern Hemisphere and shortest day of the year
17
Q
What is the March Equinox?
A
March 20 or 21 and marks the beginning of spring in the Northern Hemisphere.
Half of each hemisphere is lit, and the sunlight is centered on the equator. The hours of daylight and darkness are
approximately equal everywhere on Earth on these days, about 12 hours.
18
Q
What is the June Solstice?
A
June 21 or 22, when the North Pole’s tilt toward the sun is greatest, the South Pole is in complete darkness. This solstice marks the beginning of summer in the Northern Hemisphere and is the longest day of the year
19
Q
Where do the Earth’s temperatures and hours of daylight stay the most constant?
A
At the equator/pole
20
Q
What direction does the Earth rotate/spin in?
A
Counterclockwise
21
Q
What is the terminator?
A
The dividing line between light and dark
22
Q
Why do seasons occur?
A
Because of Earth’s tilt (always 23.5 degrees! toward the North Star)
23
Q
What is a satellite?
A
A body that orbits a larger body (doesn’t have to be natural)
24
Q
What is a moon?
A
A natural satellite, or body that orbits a larger body.
25
What is gravity?
The force that all bodies with mass have which allows them to exert a force that pulls other objects with mass toward themselves.
26
How long does it take the moon to orbit, or revolve around, the Earth?
The moon takes 27.3 days or about a month.
27
What are lunar phases?
As the moon revolves around Earth, the portion of the moon that reflects sunlight back to Earth changes, causing the moon’s appearance to change
28
What is the first lunar phase?
The new moon, Earth, and the sun are lined up, so that the near side of the moon is unlit. There appears to be no moon in the sky.
29
What is the first quarter in the lunar phase?
When half of the near side of the moon is in the sunlight, the moon has completed one-quarter of its cycle. This is when you see sunlight on the near side of the moon, as a crescent, as the moon waxes or grows
30
What is the (waxing) gibbous phase?
This is during the second week when the near side is more than half-lit but not fully lit. The moon is halfway through its cycle, and the whole near side of the moon is in sunlight, so we see a full moon
31
What is a full moon?
when the whole near side of the moon is in sunlight, during the waxing gibbous phase
32
What is the third quarter of the lunar phase (waning gibbous)?
During the third week, the amount of the moon’s near side in the sunlight decreases and it seems to shrink, or wane. The near side is again only half in sunlight.
33
How long are the moons phases?
29.5 days (Month)
34
What is an eclipse?
An event during which one object in space casts a shadow onto another.
35
What is an umbra?
the first shadow cast during an eclipse, innermost and darkest part of a shadow, where the light source is completely blocked
36
What is a penumbra?
the second shadow cast during an eclipse that occurs as it moves away from the sun
37
What is a solar eclipse?
When the moon is directly between the sun and Earth, the shadow of the moon falls on a part of Earth and causes this.
38
What is a total solar eclipse?
When the sun’s light is completely blocked by the moon
39
What is tidal force?
the gravitational pull exerted by a celestial body that raises the tides
40
What are tides?
daily changes in the level of ocean water, and are caused by the difference in the gravitational force of the sun and the moon across Earth
41
What is high tide?
Bulges that form in Earth’s oceans, when a water level that is higher than the average sea level.
42
What is low tide?
Form in the areas between the high tides when a water level that is lower than the average sea level
43
What is a tidal range?
The difference between the levels of ocean water at high tide and low tide; it depends on the positions of the sun and the moon relative to Earth
44
What is tidal force?
The difference between the force of gravity on one side of Earth and the other side of Earth
45
What is a spring tide?
A spring tide is a tide that occurs when the Earth, Sun, and Moon are aligned, causing their gravitational forces to combine and create unusually high tides
46
What is a neap tide?
A tide in which the difference between high and low tide is the least. Neap tides occur twice a month when the Sun and Moon are at right angles to the Earth
47
What is a tidal cycle?
a tidal cycle occurs in 24 h and 50 minute intervals; it takes about 6 h and 12.5 min (one-fourth the time of the total cycle) for water in an area to go from high tide to low tide
48
What is a star?
A large celestial body that is composed of gas and emits light
49
What is a universe?
The word that scientists use to describe space and all of the energy and matter in it; there are an estimated 100 billion or more galaxies in the universe
50
What is a galaxy?
Stars grouped together in structures; a large collection of stars, gas, and dust
51
What is a solar system?
the collection of large and small bodies that orbit our central star, the sun
52
What is a planet?
a large spherical body that orbits the sun; there are 8 in our solar system
53
What are the terrestrial planets?
the four planets that orbit nearest the sun, including Mercury, Venus, Earth and Mars; they are rocky, dense and relatively small
54
What are the gas giant planets?
the four planets orbiting away from the sun, including Jupiter, Saturn, Uranus and Neptune
55
What are moons?
smaller bodies orbiting planets; Earth has one, but Jupiter has more than 60
56
What is a star?
a large celestial body that is composed of gas and emits light; most are composed almost entirely of hydrogen and helium.
57
What is a galaxy?
a large collection of stars, gas, and dust that held together by gravity
58
What is a spiral galaxy?
galaxies that are shaped like pinwheels. They have a central bulge from which two or more spiral arms extend. Stars form in or near the spiral arms. An example is the Milky Way Galaxy.
59
What is a nebula?
a large cloud of gas and dust in space where most stars form; they may form from stars; they form when supergiant stars explode or when stars like the sun age and push away their outer layer
60
What is supernova remnant?
Nebulae that form after supergiant stars that are much larger than the sun explode
61
What is a light year?
the distance that light travels through space in one year
62
What is the radius of the universe?
The universe has a radius of at least 14 billion light years (Note: The universe is always expanding)
63
How are smaller objects in the universe measured?
In kilometers, such as moons, planets and stars
64
What are clusters?
Areas where several thousand galaxies are found
65
What are voids?
areas in the universe where little matter exists; huge spherical volumes
66
What are superclusters?
Areas where ten or more thousand galaxies are found
67
What are emission nebula?
bright, diffuse clouds of ionized gas that emit their own light
68
What is a reflection nebula?
a cloud of interstellar dust and gas that shines by reflecting light from nearby stars instead of producing its own light
69
What is a star?
star is a large celestial body that is composed of gas and emits light; made mostly of hydrogen and helium; they emit light and vary in brightness.
70
What is a red star?
a "cool" star
71
What is a blue star?
a "hot" star
72
What is a multiple star or multiple star system?
Three or more stars that are bound together by gravity, which causes those stars to orbit each other.
73
What is the core?
the center of the sun; there gases are compressed and heated, and temperatures reach 15,000,000 °C. This is where matter is converted into energy
74
What is the photosphere?
The sun’s surface. It is the layer of the sun’s atmosphere that we see from Earth, with an average temperature of 5,527 °C.
75
What is the chromosphere?
The sun’s middle atmosphere. It is 4,225 °C to 6,000 °C.
76
What is the corona?
The sun’s outer atmosphere. It can reach 2,000,000 °C.
77
What is apparent magnitude?
The measure of a star’s brightness as seen from Earth. Some stars are actually more luminous, or brighter, than the sun is. If these stars are located far from Earth, they may not appear bright to us.
78
Faint stars have what kind of numbers?
positive (larger) numbers
79
Bright stars have what kind of numbers?
negative (smaller) numbers; for example, the brightest star in the night sky, Sirius, has -1.46; the sun has a magnitude of -26.8, not because it is as luminous, but because it is located closer to the Earth
80
What is luminosity?
the actual brightness of a star
81
What is absolute magnitude?
a measure of how bright a star would be if the star were located at a standard distance; a measure of the brightness of a star whose distance from Earth is known
example: the apparent magnitude of the Sun is -26.8, while the absolute magnitude of the Sun is +4.8, which is typical of many stars. The Sun is 8.3 light-minutes from Earth.
Sirius is located 8.6 light-years from Earth. Sirius has an apparent magnitude of —1.46 and an absolute magnitude of +1.4. It is far more luminous.
82
What is a black body?
When an object’s color depends only on temperature; as the temperature of a black body rises, it glows brighter and brighter red. As it gets hotter, its color changes to orange, yellow, white, and blue-white. It also glows more brightly
83
What are red stars?
Stars that have the lowest surface temperatures (below 3,500 °C)
84
What are blue stars?
Stars that have the highest surface temperatures (above 25,000 °C)
85
What are yellow-white stars?
Stars with middle temperatures that have between 6,000 - 7,500 degrees C
86
How do astronomers measure the size of stars?
Solar radii. Astronomers use the radius of the sun which is approximately 695,000 km, or about 109 times the radius of Earth.
87
What are white dwarfs?
very small stars that are about the same size as Earth; about .01 solar radi
88
What are giant stars?
very large stars that typically have sizes between 10 and 100 times the radius of the sun
89
What are super giants?
Rare, extremely large stars that have sizes of up to 1,000 solar radii; are often red or blue stars
90
Where do stars form? (step 1)
Stars form in nebulae. A nebula is a large cloud of gas and dust. Like stars, nebulae are composed of mostly hydrogen and helium.
91
What are dense cores? (step 1)
The force of gravity increases with increasing mass and decreasing distance between objects. As particles within the nebula are pulled closer together, gravitational attraction increases. As a result, dense regions of gas and dust form within the nebula. These are the densest regions in nebula where new stars are formed
92
What is nuclear fusion and when does it take place? (step 2)
at 10 million degrees celcius this takes place, when high temperature and pressure cause two or more low-mass atomic nuclei to form a heavier nucleus. A nucleus is an atom’s central region, which is made up of neutrons and protons. Nuclear fusion (or hydrogen fusion) marks the first of a star; it is the longest stage in the life cycle of a star and last for billions of years, stops when star runs out of hydrogen
93
What happens when all the hydrogen has fused into helium? (step 3)
Nearly all the hydrogen has fused to helium and he core of the star contracts under its own gravity. This increases the temperature of the core. Energy is transferred to a thin shell of hydrogen that surrounds the core. Hydrogen fusion continues in this outer shell. The outer shell of the star expands, which makes the star grow much larger.
When fusion ends completely, stars begin to eject matter. Stars rapidly lose mass until only the core remains.
94
What is a white dwarf?
a low mass star, like our sun
White dwarfs shine for billions of years before they cool completely. As white dwarfs cool, they become fainter. This is the final stage in the life cycle of low-mass stars
95
After nuclear fusion is complete, what does a high mass star become?
a supergiant
96
What is a supernova?
explosion of a super giant
97
What is a neutron star?
a small, incredibly dense ball of closely packed neutron, which occurs when the core of a supernova collapses under the force of gravity.
98
What is a pulsar?
Neutron stars that rotate very rapidly and emit a beam of electromagnetic radiation that can be detected every time the beam sweeps by Earth
99
What is a black hole?
When the most massive super giants collapse, they form black holes. The stars are so massive, so the cores continue to collapse and compress into a single point (Note: Nothing can escape black holes including light)
100
What is luminosity?
a measure of the total amount of energy a star gives off each second, or its brightness.
101
What is the H-R diagram?
Hertzsprung-Russell diagram is how scientists measure the brightness and life cycle of stars; the hottest stars are on the left and blue; the coolest stars are on the right and red; the brightest stars are at the top (at the beginning of their life cycle), while the dimmest stars are at the bottom (at the end of their life cycle)
102
What is the main sequence?
region of H-R diagram where stars spend most of their lives; here they are actively fusing hydrogen
Sun is a main-sequence star. When nuclear fusion ends in the sun, it will become a giant and will move to the upper right corner of the H-R diagram. When the outer layers of the giant are lost to space, the sun will become a white dwarf and move to the bottom of the diagram
103
What is electromagnetic radiation?
Energy traveling as electromagnetic waves; Waves can be described by either their wavelength or frequency.
104
What is wave length and what is frequency? When do waves have shorter wavelengths?
Wave length is the distance between two adjacent crests or troughs of a wave. Frequency measures the number of waves passing a point per second.
Higher-frequency waves have a shorter wavelength.
Energy carried by electromagnetic radiation depends on both the wavelength and the amount of radiation at that wavelength. A higher-frequency wave carries higher energy than a lower-frequency wavelength.
105
What is the electromagnetic spectrum?
All known wavelengths and frequencies make up. A spectrum (plural, spectra ) is a continuous range of a single feature, in this case wavelength
106
What are the seven types of known wavelengths and their frequencies?
1. Radio and television waves - longest wavelength and lowest frequency; these produce sound waves (NOT electromagnetic radiation)
2. Microwaves have shorter wavelengths and higher frequencies than radio waves.
3. Infrared, which is sometimes called “heat radiation"
4. Visible light. Images produced in visible light are the only images we can see without computer enhancement
5. Ultraviolet radiation (sun burn)
6. X-rays
7. Gamma ray (shortest wavelength and highest frequency)
107
What is a spectroscope?
instrument that measures the chemical make-up or spectrum of light of an object by separating visible light into patterns/wavelengths (rainbow); light passes through a prism
Spectroscopes can tell us the chemical composition of substances; analyze spectra to learn about the motion and distance of objects. They can also learn about the properties of objects, such as composition and temperature
108
What is a continuous spectra?
shows all colors of light without any gaps
109
What is an emission spectrum?
a series of unevenly spaced lines of different colors and brightnesses. Each color corresponds to a certain wavelength of light that is emitted
110
What is an absorption spectrum?
looks a lot like a continuous spectrum but shows dark lines where gas absorbs light
111
What is the Doppler effect?
an observed change in frequency or wavelength when the source is moving with respect to the observer
(wavelength increases, frequency decreases, sound is higher)
112
What is a blueshift?
When a star is moving toward Earth, the wavelengths emitted by the star are compressed and appear blue to an observer on Earth. A blueshift occurs. (Think blue is good you want it to come to you)
113
What is a redshift?
When a star is moving away from Earth, the wavelengths are stretched out. A redshift occurs (Think red is bad you want it to go away)
114
What is the hubble constant?
the speed of an object in space; the faster its traveling away from Earth, the farther away it is
115
What is a telescope?
an instrument used to collect and concentrate electromagnetic radiation; optical telescopes were the first instruments and gathered visible light
116
What are non-optical telescopes?
these telescopes are used to collect electromagnetic radiation outside of the visible region, such as radio waves or x-rays
117
What is a reflecting telescope?
(see things far away) The Hubble Space Telescope is an example; uses mirrors to produce an image from light
118
What is a refracting telescope?
(see things closer, in our solar system) uses lenses to produce a magnified image
119
Why are telescopes often built in mountains and away from cities?
Because the atmosphere is thinner higher up, and because it doesn't then absorb light from cities
120
What do microwave telescopes do?
They tell us about the formation of the early universe
121
What are radio telescopes and how are they used?
detect radio waves from objects in space; have smooth, curved surfaces that look like a satellite dish; very large; learn about the properties of dust clouds where stars, planets, and new solar systems form; provide details about the temperature and density of the dust clouds and the size of the structures in the clouds; study the activity on the sun, including solar flare
122
What do x-ray telescopes do?
Analyze very hot areas and black holes, exploding stars; they have to be in space and orbit the earth, b/c Earth's atmosphere blocks x-rays
123
What do infrared telescopes see?
composition of atmosphere of planets and moons, whether planets are forming
124
What do ultraviolet telescopes see?
solar cycles, young stars, and star formations
125
What do gamma ray telescopes see?
very high energy, explosions of the most massive stars
126
What are the different types of structures in the universe?
1. Solar system 2. star cluster (3 or more) 3) galaxy 4) galaxy cluster (dozens) 5) supercluster (hundreds)
127
What is false color?
a technique that astronomers use to make images taken by telescopes more meaningful and reveal more detail than the human eye can see
128
What is the law of universal gravitation and who was responsible for it?
Sir Isaac Newton; every object in the universe attracts other objects; the force of the attraction depends on the masses of the objects and the distance between them
129
What is the theory of special relativity and who was responsible for it?
Albert Einstein; this theory states that space and time are relative. Relative means that they depend on the motion of the observer and the object being observed. (Note: His theories were inspired by Newton)
130
What is the theory of general relativity and who was responsible for it?
Albert Einstein; this theory explains how gravity causes space and time to curve; in 1921 Einstein won the Nobel Prize in Physics; his studies indicated the universe was expanding
131
Who proposed that the universe is expanding and developed the currently accepted theory of the origin of the universe?
Georges Lemaître; he used Einstein’s equations to show that the universe is expanding; explained the relationship between the distances of galaxies and the speeds at which those galaxies are moving away from Earth; He thought that if the universe was expanding, all matter must have been packed into a very small space—a “primeval atom”—at some time in the past
132
Who provided evidence that the universe is expanding and how?
Edwin Hubble; he observed a redshift in the light that was coming from distant galaxies; this happens when the object moves away from an observer, ie, most galaxies were moving away from Earth; the fainter and farther away a galaxy appeared, the greater its redshift. Therefore, the greater a galaxy’s distance from Earth, the faster it is moving away from Earth
133
Who outlined the theory of how elements formed in the universe?
George Gamow; most of the visible matter in the universe is hydrogen and helium; heavier elements formed later in stars
134
What is the Big Bang Theory?
the universe began with a tremendous expansion 13–15 billion years ago; all of the contents of the universe existed in a tiny volume that suddenly began expanding in all directions.
135
How does the redshift of galaxies support the Big Bang Theory?
Because galaxies are moving apart, they must have been closer together in the past; the farther away a galaxy is, the faster it is moving
136
What is CMB?
the Cosmic Microwave Background (CMB) are traces of early radiation from the creation of the universe
137
How does the abundance of light elements in the universe support the Big Bang Theory?
abundance of light elements in the early universe can be compared with the abundance of light elements in stars today; scientists study stars that are very far from Earth and in the early stages of development. Scientists analyze the spectral lines of theses tars to determine the amounts of elements being produced within their cores. The percentages of light elements in these stars are very close to the theoretical values predicted by the Big Bang theory
138
What is inflation?
the brief period of very rapid expansion immediately after the Big Bang; the universe was no bigger than an atom and was extremely dense and hot at 1 x 10 to the 32 K.
Matter and energy began to spread out rapidly in all directions. The temperature and density of the universe decreased quickly; lasted only a few fractions of a second; after inflation, the universe began to expand at a slower rate
139
What is the currently estimated age of the universe?
between 13 and 15 billion years
140
How do scientists estimate the age of the universe?
They use the present rate of expansion, or how fast galaxies are moving away from Earth
141
What is a redshift?
apparent shift toward longer wavelengths of light caused when an object moves away from an observer
142
What is remote sensing?
describe the process of gathering and analyzing information about an object without physically touching the object
143
What is continental drift?
the hypothesis proposed by Wegener that today’s continents (7) were once part of a single landmass, or supercontinent, called Pangaea.
144
Who first noticed that continents had coastlines that seemed to match up?
Abraham Ortelius, a mapmaker
145
What fossil and rock evidence exists to support the theory of continental drift?
Fossils of the same plant and animal species are found on continents separated by vast oceans. Scientists infer that when these plants and animals were alive, the continents were joined.
There are also matching rock layers and land features that match up on different continents.
146
What is the climatic evidence for continental drift?
Both past glacial ice distribution and coal deposits supported the theory because there deposits matched up if you put the continents together.
147
What is the theory of plate tectonics?
Earth’s surface, or outer layer is made up of giant, moving slabs or puzzle pieces.
148
What is the lithosphere?
Earth's outer layer made up of tectonic plates
149
What is the asthenosphere?
Earth's layer under the lithosphere (or tectonic plates); differences in temperature and pressure cause material to slowly move, which makes the tectonic plates above to move too
150
What is a theory?
a system of ideas that explains many related observations about the natural world, based on a lot of evidence; this is how a hypothesis becomes a theory in science
151
What evidence supports plate tectonics?
mapping the following three: sea-floor spreading, sea-floor rock, and earthquakes and volcanos
152
What is sea-floor spreading?
the process by which a new sea floor is formed. this occurs at underwater mountain belts called mid-ocean ridges, where magma rises to the surface and solidifies, forming a new sea floor
153
What is subduction?
A geologic process in which one edge of one lithospheric plate is forced below the edge of another.
154
What is magnetic reversal?
the change of the magnetic poles (North and South poles have switched repeatedly) The last major magnetic reversal of Earth's magnetic field occurred around 780,000 years ago, but the exact timing is debated.
155
What is magnetic reversal pattern?
a striped pattern of rock, due to the switching of Earth's poles and the switching of aligning of magnetic minerals in newly formed rocks
156
Why are earthquakes and volcanoes evidence for the plate tectonics theory?
Because most active volcanoes are found near and earthquakes occur near plate boundaries
157
How does research about plate tectonics affect society?
We know the location of earthquakes and volcanoes. We are also able to locate valuable resources like minerals and fossil fuels.
158
The lithosphere is broken up into how many major tectonic plates?
around 15, which differ in size, shape, density, thickness, and composition.
159
Tectonic plates are composed of two types of lithosphere?
oceanic or continental lithosphere—or both.
160
What is oceanic lithosphere?
made of younger rock and generally denser than continental lithosphere and sinks (or goes down)
161
What is continental lithosphere?
is thicker and older than oceanic lithosphere (lifts or goes up)
162
What is deformation?
the bending, tilting, and breaking of rock. It changes the shape and size of features on and below Earth’s surface. three types of stress can cause it
163
What is stress?
the amount of force per area put on a body, tectonic plate movement puts stress on rock; there are three types of stress, which cause deformation
164
What is tension?
the second kind of stress, when rock is lengthened or pulled apart (it can deform rock by breaking it)
165
What is compression?
the first kind of stress, when rock is squeezed or shortened
Rock that is less rigid bends instead of breaks. Rock that is more rigid breaks, (or faults)
166
What is sheer stress?
the third kind of stress, when rock grinds against and moves past each other (transform boundary)
167
What is a convergent boundary?
When tectonic plates move toward each other and collide
168
What is a divergent boundary?
When tectonic plates move away from each other or diverge; new lithosphere is formed at divergent boundaries; most are under the ocean
169
What is a transform boundary?
where two tectonic plates move horizontally past each other (sheer stress commonly occurs); most are on the ocean floor, but one examples of ocean-land is the San Andreas Fault in CA
170
What are folded mountains?
a result of convergent boundaries, with the collision of two continental plates which result in high mountain ranges (compressed, folded and faulted upward)
171
What are volcanoes?
a result of convergent boundaries, with the collision of oceanic and continental plates, or oceanic and oceanic plates
172
What are ocean trenches?
the deepest landform on the ocean floor
173
What are fault block mountains?
a rock formation that occurs at divergent boundaries, when blocks of lithosphere are lifted up or dropped down
174
What are rifts?
rock formation that occurs at divergent boundaries, when Earth's lithosphere pulls apart to form long, narrow, faulted rift valleys
175
What features are associated with transform boundaries?
major and minor earthquakes
176
What are hot spots?
volcanic landforms that occur far away from plate boundaries, where volcanic island chains form
177
What is a map?
models that represents Earth's surface; they can show large areas of Earth’s three-dimensional landscape on small, flat surfaces.
Physical maps show land features, such as mountains, rivers, and valleys.
Political maps show areas such as territories, states, counties, and cities.
Other map types might show resources, elevation, or roads
Maps can be combined to show more information on one map.
178
What are aerial images?
images taken from planes
179
What are satellite images?
images are taken from space by satellites that orbit Earth
180
What is a geologic map?
maps that show rock types and ages; they also show geologic features such as fault lines
181
What is topography?
the shape and size of the land features on Earth’s surface (ie, moutainous, hilly or flat)
182
What is a topographic map?
a map that shows the shape of Earth’s surface with lines that represent different elevations; it may use different symbols to show a variety of natural and human-made features, such as rivers, lakes, cities, and parks; you might see depositional features, such as alluvial fans, deltas, and floodplains
US uses feet and miles
Other countries use meters and kilometers
183
What is a contour line?
most of the lines on a topographic map and they are usually curved and smooth; they connect points of equal elevation; shapes formed by the contour lines show the shape
* All points along a contour line represent a single elevation.
* A contour line forms a complete, closed loop. You may only see part of the loop if a contour line runs off the edge of a map.
* A contour line never forks or splits apart.
* Contour lines almost never cross.
* Contour line spacing depends on the land’s steepness. Closely spaced lines represent a steep slope. Lines spaced far apart represent a gentle slope
184
What is relief?
the difference between the highest and lowest elevations in an area
relief describes how areas can differ in steepness; steep mountains have high relief, while flat plains have low relief
185
What is a contour interval?
the difference in elevation between two contour lines
186
What is an index contour?
a thicker contour line that often has an elevation label
187
What is a map scale?
a scale that shows the relationship between the sizes and distances shown on the map and the actual measurements on Earth’s surface
For example, consider a map with a scale of 1:10,000. 1 inch on the map equals 10,000 inches on Earth’s surface.
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What is slope?
measures steepness from one point to another, using rise over run. The change in elevation is the rise, the change in horizontal distance between the two points is the run
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What is convection?
the movement of matter (air) due to differences in density (based on temperature)
Cold air is denser than warm air, so cold air sinks. When denser air sinks, it places greater pressure on the surface of Earth than warmer, less-dense air does. This results in areas of higher air pressure. Air moves from areas of higher pressure toward areas of lower pressure.
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What is wind?
the movement of air caused by differences in air pressure; the greater the differences in air pressure, the faster the air moves
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The warming and cooling of air produces pressure belts every _____ degrees of latitude?
30 degrees latitude
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What kind of air creates areas of high pressure at Earth’s north and south poles?
Cold air
Warm air creates less pressure and forms at the equator
This pressure gradient results in global movement of air.
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What are convection cells?
smaller, circular patterns of air; as air moves from the equator, it cools and becomes more dense
At about 30°N and 30°S latitudes, a high-pressure belt results from the sinking of air
Cold air warms as it moves away from the poles. At around 60°N and 60°S latitudes, a low-pressure belt forms and pushes air upward
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What is the Coriolis effect?
an apparent force that causes objects traveling long distances around the Earth to appear to curve instead of moving in a straight line, due to the Earth's rotation
winds in the Northern hemisphere curve to the right
winds in the Southern hemisphere curve to the left
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What are global winds?
wind systems that occur at or near Earth’s surface
the major global wind systems are the polar easterlies, the westerlies, and the trade winds.
Calm areas include the doldrums and the horse latitude
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What are the trade winds?
A major wind system that blow between 30° latitude and the equator in both hemispheres. Curves to the west
Trade winds in the Northern Hemisphere come from the northeast, and trade winds in the Southern Hemisphere come from the southeast. These winds became known as the trade winds because sailors relied on them to sail from Europe to the Americas
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What are westerlies?
a major wind current that produces rain and snow and blow between 30° and 60°latitudes in both hemispheres
the rotation of Earth causes these winds to curve to the east
in the Northern Hemisphere come from the southwest
in the Southern Hemisphere come from the northwest
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What are polar easterlies?
major winds that blow between the poles and 60° latitude in both hemispheres; form as cold, sinking air moves from the poles downward.
The rotation of Earth causes these winds to curve to the west.
In the Northern Hemisphere, polar easterlies can carry cold Arctic air over the majority of the United States, producing snow and freezing weather
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What are doldrums?
calm area around the equater where trade winds of both hemispheres meet; warm, less dense air, so low pressure, little wind blows, "dull" or "sluggish"
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What are horse latitudes?
the calm area at about 30° latitude in both hemispheres, where air stops moving and sinks; name given when sailing ships carried horses from Europe to the Americas and when they were stalled, they threw horses overboard
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What are jet streams?
narrow belts of high-speed winds that blow from west to east, between 7 km and 16 km above Earth’s surface. Airplanes traveling in the same direction as a jet stream go faster than those traveling in the opposite direction of a jet stream
the two main jet streams are the polar jet stream and the subtropical jet stream; both hemispheres experiences these jet streams
Jet streams follow boundaries between hot and cold air and can shift north and south.
In the winter, as Northern Hemisphere cools, the polar jet stream moves south. This shift brings cold Arctic air to the United States.
When temperatures rise in the spring, this jet stream shifts to the north
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What are local winds?
winds over short distances
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What is a sea breeze?
cool breeze coming off a lake or ocean toward the land during the day
the colder, denser air overwater flows toward the land and pushes the warm air on the land upward
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What is a land breeze?
wind blows from land toward the water at night
cooler air on land causes a higher-pressure zone over the land. So, a wind blows from the land toward the water
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What is a valley breeze?
during the day the air flows from the valley up the slopes of the mountains
uneven heating results in areas of lower pressure near the mountain tops
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What is a mountain breeze?
at night the air along the mountain slopes cools and moves down into the valley
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What is an ocean current?
stream-like movements of water in the ocean
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What is a surface current?
an ocean current at or near the surface of the ocean, caused by wind; most reach depths of about 100 m, but some go deeper; reach lengths of several thousand kilometers and can stretch across oceans. One of the strongest surface currents on earth is the Gulf Stream. It transports more water each year than is transported by all the rivers in the world combined. Infrared cameras on satellites can show the temperatures of ocean currents
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What affects surface currents?
three factors: continental deflections, the Coriolis effect, and global winds. These factors keep surface currents flowing in distinct patterns around Earth
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What are continental deflections?
when ocean currents meet continents, they change direction (example, when the South Equatorial Current meets South America, it turns southward); if there were no continents, currents would just go straight!
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What is the Coriolis effect?
the deflection of moving objects from a straight path due to Earth’s rotation
Earth’s rotation causes all wind and ocean currents, except on the equator, to be deflected
Points on Earth near the equator travel faster than points closer to the poles
In the Northern Hemisphere, currents (wind and water) are deflected to the right. In the Southern Hemisphere, currents are deflected to the left
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What is the major source of energy that powers surface currents?
the sun
the sun causes winds to form (due to differences in air pressure), and winds cause surface currents to form
Warm currents leave the equator (low pressure zones)
Cold currents leave the Poles (high pressure zones)
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What are deep currents?
Movements of ocean water far below the surface; they are caused by differences in water density.
Density is the amount of matter in a given space or volume. The density of ocean water is affected by salinity
and temperature.
Salinity is a measure of the amount of dissolved salts. Water with high salinity is denser than water with low salinity. Cold water is denser than warm water.
the deepest and densest water in the ocean is Antarctic Bottom Water, near Antarctica
Warm water from surface currents cools in polar regions, becomes denser, and sinks toward the ocean floor
Deep currents carry colder, denser water in the deep ocean from polar regions to other parts of Earth
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What is upwelling?
when warm surface water is then replaced by cold, nutrient-rich water from the deep ocean; very important to ocean life, lots of plankton
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What is a convection current?
a movement of water that results from density differences; can be vertical, circular, or cyclical. Think of them as a conveyor belt. Surface currents make up the top part of the belt. Deep currents make up the bottom part of the belt; they transfer energy (Water from deep currents rises to replace water that leaves in surface current)
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What do ocean currents transport?
water, dissolved solids, dissolved gases, and energy; takes a water molecule over 1,000 years to return to its starting point
convection currents carry about 40% of the energy (heat) that is transported around Earth’s surface
Ocean currents carry this energy from the equator toward the poles. When the warm water travels to cooler areas, the energy is released back into the atmosphere. Therefore, ocean circulation has an important influence on Earth’s climate
most common dissolved solid - table salt; also phosphorus and nitrogen, important for plants and animals
the most abundant gases in the atmosphere— nitrogen, oxygen, argon, and carbon dioxide—are also abundant in the ocean.
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What is weather?
the short-term state of the atmosphere at a given time or place. Includes many factors. Temperature, humidity, precipitation, air pressure, wind speed and direction, and visibility are all part of weather. Energy from the sun influences most of these factors
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How is solar energy related to weather?
There is more solar energy at the equator than elsewhere. Heat moves from warm areas to cold areas. Energy as heat is transferred from the warm tropics toward the colder poles, by air that moves in the atmosphere and by water that flows in the oceans.
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What is convection?
the movement of matter due to differences in density caused by differences in temperature
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What is a convection current?
the cycling of matter caused by differences in density; In the atmosphere and ocean, convection currents transfer energy as heat from the tropics toward the poles
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What factors influence patterns of global weather?
driven by interactions between the atmosphere and ocean; global weather generally behaves in predictable ways
Atmospheric factors include wind systems that flow across the surface of Earth. Areas of high and low pressure, seasonal changes in wind and pressure systems
Oceanic factors include the movement of surface water and sea-surface temperatures.
These factors affect weather over land and over the oceans.
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What are the atmospheric factors of global weather?
global winds, global pressure belts, and jet streams
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What is global wind?
the movement of air over Earth's surface in patterns that are worldwide; there are three kinds: trade winds, the westerlies, the polar easterlies,
Occur in both hemispheres. Because Earth rotates, winds in each of these systems curve to the east or to the west
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What are trade winds?
global winds that blow between the equator and 30º latitude. These winds curve to the west in both hemispheres. The paths of tropical storms are steered in an east-to-west direction across the Atlantic Ocean and the Pacific Ocean by trade winds
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What are westerlies?
global winds that blow between 30º and 60º latitude and curve to the east in both hemispheres. These winds generally blow from lower latitudes, bringing warm air to middle latitudes (Westerlies = WARM)
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What are polar easterlies?
global winds blow between 60º latitude and the poles and curve to the west in both hemispheres. They move cold, dry air from the poles toward the middle latitudes. In the middle latitudes, the polar easterlies meet the westerlies
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Where are the different pressure belts and what happens?
1. A LOW-pressure belt forms at the equator; warm, moist air, which rises. Air then cools and it rains a lot. Tropical storms also form in this region.
2. The westerlies and polar easterlies meet between 50° and 70° latitude in both hemispheres to form another LOW pressure belt. (b/c air rises) In the Northern Hemisphere, storms often form in this belt
3. Cold, sinking air is denser and exerts more air pressure than warm, rising air. Cold air sinks where the trade winds and westerlies blow away from each other between 20° and 40° (HIGH pressure).
The sinking air is dry. These areas have little rainfall and high rates of evaporation. Most of the world’s deserts are found in this high-pressure belt.
4. Poles the air is cold, dense, and dry. As the air sinks, it forms a belt of HIGH pressure. The poles receive little snow. Any snow that does fall remains frozen. The poles are cold deserts
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What is a jet stream?
A jet stream is a narrow band of strong, fast winds high in the upper troposphere, above global winds; two per hempisphere: the polar jet stream and the subtropical jet stream, which flow from W to E
Position changes with the seasons, following boundaries of hot and cold and trigger weather changes, like tornados and thunderstorms; for example , in the Northern Hemisphere, the polar jet stream moves southward in winter and the cold arctic air to the US; in the summer it shifts north; moves storm systems
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What are the oceanic factors of global weather?
Surface currents (like ocean currents)
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What are ocean currents?
a movement of ocean water that follows a regular pattern, if they're near the ocean surface they're called surface currents and move horizontally; result of friction b/w the atmosphere and the ocean surface
Surface winds determine the direction of surface currents, they may be warm or cold; warm surface currents generally move warm water from lower latitudes to higher latitudes. Cold surface currents generally move cold water from higher latitudes to lower latitudes
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What is the Gulf Stream?
A warm water current that flows northward along the east coast of the US; it keeps UK, Ireland and western Europe warmer than inward Europe on the same latitude, b/c of the warm air it transports
Tropical storms and hurricanes form near warm water currents, like the southern part of the Gulf of Stream, need surface temp of at least 26 degrees C; Once a storm moves over land, it rapidly loses strength
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What is the California current?
A cold water current that moves cold weather south along the west coast of the US; b/c of this, land along the west US coast is cooler than the west US coast of the same latitude; more fog along the W coast; storms weaken before they make it to the Pacific Coast, but they still produce rain
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What is ENSO?
El Niño Southern Oscillation is a periodic change in the ocean-atmosphere system in the equatorial Pacific Ocean. It is has two phases: El Niño and La Niña. Both affect wind patterns, jet stream positions, and global weather
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What is El Nino?
a periodic change characterized by above-average ocean temperatures across the Pacific Ocean; affects wind patterns, jet stream positions, and global weather
high pressure builds over the western Pacific Ocean. At the same time, low pressure builds over the eastern Pacific Ocean; trade winds weaken; winds push warmer ocean water into the eastern Pacific Ocean.
In the Northern Hemisphere, the polar jet stream strengthens and moves south; increase in rain in CA and southeastern US
The subtropical jet stream strengthens and moves north; increase in tropical storms in the eastern Pacific Ocean and rain across western South America. Droughts can occur in Southeast Asia and Australia; decreases hurricane activity in the North Atlantic
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What is La Nina?
a periodic change during which below-average ocean temperatures occur in the eastern Pacific Ocean; affects wind patterns, jet stream positions, and global weather
High pressure develops over the eastern Pacific Ocean, low pressure over the western Pacific Ocean; strong trade winds blow from east to west
During La Niña, the polar jet stream moves northward.
Snowfall increases in the Pacific Northwest and upper Midwestern states, especially near the western Great Lakes. At the same time, the central and southern United States get less rainfall than average; increases hurricane activity in the North Atlantic Ocean.
On the opposite side of the Pacific Ocean, wetter-than- normal conditions may be common in Southeast Asia and Australia during La Niña. Drought may occur in Peru and Chile
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What is weather forecasting?
the analysis of scientific data to predict future weather conditions (8 elements of weather)
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What is meteorology?
the study of weather and Earth’s atmosphere; scientists who study meteorology are called meteorologists
There are eight elements of weather which are observed: air temperature, humidity, wind direction, wind speed, clouds, precipitation, atmospheric pressure, and visibility.
Weather forecasts helps people stay safe and comfortable. Meteorologists need accurate data
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Who are the Hurricane Hunters?
pilots trained to fly in the most intense storms, i.e., tropical storms and hurricanes, to collect data; they charts the storms intensity and direction, and is sent to weather forecasters
Collect data using the nose, tail and underside
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What is a dropsonade?
a lightweight instrument package launched from the aircraft during a storm to collect data about temperature, humidity, wind speed
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How are weather data collected?
ground stations, satellites, balloons and aircraft, radars
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What are ground stations?
one way weather data is collected; often near airports, land-based ground stations; collect from the lower atmosphere 24 hours a day. Use weather-sensing instruments instruments to measure pressure, temperature, humidity, precipitation, wind speed, visibility, and cloud cover
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What is radar?
Another method for collecting weather data; used to find the location, movement, and intensity of storms; bounces radio waves off precipitation.
The stronger the signal that is returned to the radar, the heavier the precipitation is.
The longer it takes for the signal to return to the radar, the farther away the precipitation is
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What is Doppler radar?
Doppler radar, a type of weather radar, tracks severe storms and tornadoes
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How do balloons and aircraft measure weather?
measure weather conditions in the middle to upper atmosphere, such as over oceans
Weather balloons are released twice daily from stations around the world. Collect data at different altitudes and carry a small instrument package called a radiosonde, which measure atmospheric pressure, air temperature, and humidity up to about 32 km, also wind speed and direction; Radiosondes send data by radio signal to ground stations
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What are weather satellites?
satellites at high altitudes provide that data on water vapor, cloud-top temperatures, and the movement of weather systems. There are two kinds: Geostationary and polar-orbiting satellites monitor Earth’s weather
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What are geostationary weather satellites?
satellites monitor Earth from a fixed position thousands of kilometers above Earth
polar-orbiting satellites circle Earth and provide global information from hundreds of kilometers above Earth’s surface
Cameras on satellites take images at regular intervals to track weather conditions on Earth. Digital images are sent back to ground stations. These images can be animated to show changes in weather over time
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What is the NWS?
The National Weather Service, where meteorologists in the US collect and analyze data; they prepare weather maps and station models to make it easier to understand
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What is a station model?
a set of meteorological symbols that represent the weather at a particular observing station; often shown on weather maps; makes it possible to see large weather patterns, such as fronts
Key weather elements shown are temperature, wind speed and direction, cloud cover, air pressure, and dew point. Note that the pointer, or wind barb, for wind direction points into the wind
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What is a surface weather map?
show forecasts on television; displays air pressure, the locations of fronts, and sometimes precipitation
Air pressure is shown by using isobars.
Isobars are lines that connect points of equal air pressure and are marked in units called millibars. Isobars form closed loops. The center of these loops is marked with either a capital H (high) or L (low).
Fronts are shown on surface weather maps. Blue lines with blue triangles are cold fronts. Red lines with red half circles are warm fronts. Stationary fronts alternate between blue and red
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What are upper air charts?
type weather map based on data collected by instruments carried into the atmosphere by weather balloons.
Show wind and air pressure at middle and upper levels of Earth’s atmosphere.
Indicates if and where weather systems will form, move, remain stationary, or fall apart.
Determine the position of jet streams
Airlines and airplane pilots use upper-air charts to determine flight paths and possible areas of turbulence
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What is a short-range weather forecast?
weather forecasts that makes predictions about the weather 0 to 3 days into the future
Temperature, wind, cloud cover, and precipitation are predicted with different degrees of accuracy
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What is a medium-range weather forecast?
forecasts predict weather conditions between 3 days and 7 days into the future
temperature, wind, cloud cover, and precipitation are predicted with different degrees of accuracy
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What is a long-range weather forecast?
NWS issues long-range forecasts for weeks to months into the future; using sea surface temperatures and high-level winds, forecasters can make general predictions; For example, if the weather will be warmer or colder or wetter or drier than average for a certain region. However, they cannot predict the temperature or if it will rain on a particular day.
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What are the three types of hazardous weather forecasts issued by the NWS?
weather advisory, weather watch and weather warning
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What is a weather advisory?
the expected weather conditions are not a serious hazard but an inconvenience
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What is a weather watch?
severe weather conditions are possible over a large geographic area; people should prepare and have a plan of action
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What is a weather warning?
when weather conditions pose a threat to life and property; people who live in the path of the storm need to take immediate action
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What is an ecosystem?
a community of species and their nonliving environment. Living and nonliving things interact constantly in an ecosystem
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What are abiotic factors?
the nonliving parts of an ecosystem, including water, air, soil, sunlight and temperature
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What are biotic factors?
the living parts of an ecosystem and their interactions
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What are the levels of organization in an ecosystem?
individual, population and community
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What is an individual?
one organism, which is the smallest level of an ecosystem
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What is competition?
happens when two or more organisms try to get the same resource. For example, prairie dogs compete with each other for biotic factors such as mates and food. Individual plants on the prairie compete with each other for abiotic factors such as space, water, and nutrients
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What is a population?
a group of individuals of the same species that live in the same area; the level of organization above an individual in an ecosystem.
For example, all prairie dogs in this prairie make up one population.
Not all populations can live in the same part of an ecosystem. Different populations have different roles to play.
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What is a community?
made up of all the populations of different species that live in the same area, and is the largest level of organization in an ecosystem
The community in this prairie ecosystem is made up of populations of grasshoppers, prairie dogs, bumblebees, yellow coneflowers, and many other species.
Every ecosystem has different species in its community. These species compete for a limited number of resources. If resources decrease, populations in a community may also decrease in number or even leave the community
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What is a habitat?
where a population lives in an ecosystem; can be as large as an lake or as small as the leaf;
often depends on abiotic factors. For example, ferns may live in wet soil in a forest ecosystem. Pine trees may live in drier soil in that same ecosystem.
A population’s habitat can also depend on biotic factors. Squirrel monkeys like the ones above find food and shelter in the trees of a tropical rain forest ecosystem. So trees are part of their habitat
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What is a niche?
the role a population plays in its community; includes its interactions with other populations; also includes the biotic and abiotic factors the population needs to survive.
For example, sea anemones occupy a niche in the sunny, warm waters of a coral reef.
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Why does competition occur in an ecosystem?
Resources are limited. Organisms may compete for the same biotic or abiotic resource. Competition can happen between members of the same or different species, between individuals or between entire populations, and be direct or indirect
Competition for resources can limit the number of populations in an ecosystem. It can also cause populations to decrease or become extinct within that ecosystem too
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What is a producer?
producers convert energy into food; most use energy from the sun to make food, through the process of photosynthesis
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What is photosynthesis?
a process when producers use sunlight to change carbon dioxide and water into sugars and oxygen; they release oxygen and store the sugars as food for later use. These sugars fuel cell processes.
Green plants and algae are examples of producers that use photosynthesis
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What are decomposers?
gets energy by breaking down organic matter; they live in soil or on rotting logs in a forest. Fungi, bacteria, and earthworms are all decomposers.
Decomposers play an important role as they breakdown waste and dead organisms, and return nutrients to the soil. w/o them, nutrients and energy would remain trapped in dead organisms instead of moving through the ecosystem.
Scavengers are sometimes classified as decomposers. They are animals that feed on dead animals, like vultures and raccoons
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What is a consumer?
an organism that gets energy by eating other organisms
There are different types of consumers.
An herbivore, such as a deer, eats plants.
An omnivore, such as a grizzly bear, eats both plants and animals.
A carnivore, such as a shark, only eats other animals.
The predator-prey relationship is a common feeding relationship in an ecosystem.
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What is a predator?
an animal that kills and eats all or part of another animal
Predators in ecosystems include lions, wolves, sharks, and birds such as the kingfisher shown here.
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What is prey?
The prey is the animal that is killed and eaten
Prey include zebra, rabbits, mice, insects, and many species of fish. Many animals can be both predator and prey. For example, a trout is a predator that eats insects. A trout can also be prey to a bald eagle.
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What is a food chain?
A food chain uses arrows to show how energy flows from one organism to the next. A food chain for the pond ecosystem described here would start with algae and look like this:
algae, small fish, large fish, osprey
In ecosystems, energy flows from one organism to the next
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What is a food web?
a model that shows the many feeding relationships in an ecosystem; it is made up of many food chains
Notice the arrows point toward each organism that is getting energy. Most organisms get energy from several different sources.
Producers form the base of most food webs. Most producers get energy from the sun. Energy flows from producers to primary consumers that eat them. Then to secondary consumers. Levels of consumers can continue to increase, depending on the number of organisms in the food web
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What is mutualism?
symbiotic relationship that is positive for both organisms; for example, bats and flowers, as bats get food and flowers get help with reproduction
Some mutualistic relationships are exclusive (ie, they cannot survive without each other). Certain fungi live on the roots of plants. The fungi get nutrients from the roots. They also help the plants to take in nutrients from the soil. The fungi cannot live without the plants. If the plants are moved to an area without the fungi, they can also die
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What is symbiosis?
a relationship in which two organisms live in close association with each other. It may involve food, shelter, protection, or other needs. Can be helpful, neutral, or harmful to one or both of the organisms in the relationship. Include mutualism, commensalism, and parasitism
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What is commensalism?
a relationship that is positive for one organism and has no effect on the other.
For example, orchids on trees in tropical rain forests; remora fish on sharks in the ocean
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What is parasitism?
a relationship that is positive for the parasite and negative for the host.
For example, the strangler fig is a parasite whose seeds get stuck in cracks of tree bark. After it sprouts and grows, it takes over the tree and eventually, the tree can die.
Some parasites use different hoses during different stages of their lives. For example, a young tapeworm may live in the muscles of a fish. If a dog eats the fish, the tapeworm may grow into an adult in the dog’s intestines. Tapeworm eggs can be passed in feces. If water washes these eggs into streams, aquatic organisms can eat them and become infected.
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What is a terrestrial ecosystem?
an ecosystem on land; trees, grasses, fungi, worms, squirrels, birds, and bears can live in terrestrial ecosystems. These organisms and their interactions make up the biotic factors in a terrestrial ecosystem
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What are abiotic factors in a terrestrial ecosystem?
soil type, temperature, amount of water, and amount of sunlight; they influence the type of organisms that can live in an ecosystem
for example, high temperatures and high humidity in a tropical rain forest allow many different types of plants to live there. However, the lack of light in some of these thick forests limits the number of plants that can grow on the dark forest floor
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What is a biome? What are the eight major biomes?
a major regional or global community of organisms; much larger than an ecosystem. Many different ecosystems can be found in any biome; characterized by their climate conditions and plant communities.
Each biome has a distinct set of climate conditions, including typical temperature range and amount of precipitation.
Climate affects the plant communities that can live in the biome. For example, a tropical rain forest biome has a warm, moist climate. This climate can support many layers of plants, such as orchids, banana trees, and rubber trees.
Latitude is one factor that affects climate. Latitude is the distance of a place north or south of Earth’s equator. Areas at lower latitudes get more sunlight and have warmer temperatures than areas at higher latitudes. Similar climate conditions explain why certain biomes are found at similar latitudes around the world.
Eight biomes:
Desert
Tropical Grassland
Temperate Grassland
Tropical Rainforest
Temperate deciduous forest
Temperate rain forest
Taiga
Tundra
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What is a tundra?
an arctic biome that is cold and dry; temperatures range from –32 °C in winter to 4 °C in summer. Yearly precipitation can be less than 38 cm, which includes melted snow. Tundra soil has a layer of permafrost, which stays frozen all year long. Mosses, lichens, grasses, and some flowering plants grow in the tundra. Lemmings, caribou, arctic ground squirrels, arctic foxes, wolves, and polar bears can survive in the tundra
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What is a desert?
the driest biome with often only a few centimeters of rain fall in a desert each year; temperatures can reach 40–50 °C during the day. At night, they can drop to 0 °C.
Soil is dry with few nutrients; plants have shallow roots to take up water when it rains. Some cacti have stems that store water. They also have spines (modified leaves) that prevent water loss. Desert animals are adapted to extreme temperatures and lack of water; many animals sleep in burrows during the day. These animals are active at night, when it is cooler
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What is a grassland?
grasses dominate grassland biomes; there are frequent fires, which prevents most trees from; hoofed animals that eat grasses are common
Prairies and steppes are temperate grasslands; temperatures in temperate grasslands can fall to 0 °C during winter;
Bison and pronghorn are found in prairies.
Savannas are tropical grasslands; Tropical grasslands are warmer and may have more rain than temperate grasslands; Zebras and antelope are found in savannas
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What are taiga?
a boreal forest, which is the northernmost forest biome, with long, cold winters and short summers; soils can stay frozen all year.
Mosses and cone-bearing trees such as spruce and pine are common plants; Moose, deer, mink, owls, wolves, and lynx are animals that can live there. Many bird species nest in the taiga during the summer
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What are the three forest biomes?
Tropical rain forests, temperate rain forests, and temperate deciduous forests
Tropical rain forests have warm, wet climates all year round.
Temperate rain forests have wet climates and seasonal temperature changes.
Temperate deciduous forests have seasonal temperature changes and less precipitation than rain forests.
Animal and plant life is rich in forests. The inhabitants of tropical rain forests include trees and vines, sloths, monkeys, insects, and birds. Temperate rain forests have cone-bearing trees and animals such as owls, elk, and cougars. Temperate deciduous forests have trees that lose their leaves in the fall. Mice, squirrels, deer, woodpeckers, and black bears are common animals in this biome
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What is the main abiotic factor that makes a temperate rain forest different from a temperate deciduous forest?
climate; this explains why similar biomes are found at similar latitudes (or climates) around the globe
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What are the feeding relationships in a terrestrial ecosystem?
Plants are the producers in a terrestrial ecosystem; primary consumers in an ecosystem eat producers; secondary consumers eat primary consumers
For example, in a desert food web, mesquite is the producer, grasshoppers and kangaroo rats are primary consumers; the great horned owl is a secondary consumer (great horned owl is also a predator)
Some organisms can gain energy and nutrients from other organisms without killing them. For example, an ear tick can attach a pronghorn and suck its blood; the tick is a parasite. it doesn't kill its host but can make it sick or weak
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How do terrestrial organisms compete with each other?
biotic factors compete for mates, food, territory and water
abiotic factors compete for sunlight, water, soil, and soil nutrients
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What are the major types of freshwater ecosystems?
take up only about 1% of Earth’s surface; all have water with a salt concentration of less than 1%; includes lakes, ponds, rivers, streams, and wetlands.
Lakes and ponds are depressions filled with still water. Lakes are bigger than ponds. Rivers and streams have flowing water. Rivers are usually wider and deeper than streams.
Wetlands are areas of land covered by fresh water for all or part of the year. Like lakes, the water in wetlands is mostly still
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What abiotic factors affect freshwater ecosystems?
Temperature, water depth, water flow rate, light levels, and oxygen levels are abiotic factors that affect freshwater ecosystems.
The importance of each factor is different in each type of fresh water ecosystem. For example, water flow rate is important in a river or stream. A fast-moving stream can carry many particles that are food for fish or insects.
Oxygen levels are important in a lake or pond. Fish can die if oxygen gets too low in a lake
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Where are examples of freshwater ecosystems found?
Lakes and ponds are found where depressions in the land fill with rain water or water from springs. Some lakes are so small you can walk around them. Others are as big as whole states.
Rivers and streams can start from small springs or melting snow in the mountains. This water runs downhill and forms channels of flowing water.
Wetlands are often found where underground water is near the surface. Water levels change over time in a wetland
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What are biotic factors in still water environments?
Algae, fish, and some plants and insects live underwater in lakes and ponds. Cattails, frogs, birds, and mammals such as muskrats live at the edge of the water. Each organism is adapted to survive in this still-water environment.
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What are examples of freshwater ecosystems with changing water levels? How are they good for the environment?
Wetlands are areas of land that are covered with water whose levels change due to climate, weather, and location. Bogs, marshes, fens, and swamps are types
They are very productive ecosystems, which means they have a large amount of living matter per unit of area. They have important environmental, functions bc they filter and clean water as it moves through wetlands; they also protect surrounding areas from flooding and pollution
Alligators live here!
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What are ecosytems with moving, fresh water?
Rivers and streams; they have both deep and shallow parts.
Microorganisms such as giardia can also be found in rivers or streams; this is parasite that lives in the small intestines of host animals
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What is an estuary?
a partly enclosed body of water where a river flows into an ocean (always coastal area); this when nutrient-rich river water mixes with salty ocean water and creates a very productive ecosystems. Many organisms use estuaries for nesting and breeding.
Plants such as seagrass, eelgrass, marsh grass, and mangroves can live in estuaries. So can animals such as fish, shrimp, clams, crabs, and ducks.
Examples include the Galveston Bay system in Texas and the Chesapeake Bay system in Maryland and Virginia
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What abiotic factors affect an estuary?
some of the same abiotic factors that affect freshwater ecosystems also affect estuaries: temperature, water depth, light levels ,oxygen levels, and water flow rate. Because estuaries are found in coastal areas, they are also affected by tides. Tides cause daily changes in water levels and salt levels.
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How do organisms in estuaries deal with changing salt levels?
Some fish swim to different areas of the estuary. Some mussels close their valves . Crabs and some birds have glands that can get rid of extra salt quickly. The roots of cord-grass plants remove salt from the water before they take it in.
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How do organisms in estuaries deal with changing water levels?
Typically there are two high tides and two low tides each day.
Oysters close their shells and stop feeding. They switch to anaerobic respiration, which lets them survive without oxygen. When the water level rises, oysters open their shells. They use their gills to take in oxygen again.
When water levels are low, the temperature of the water increases. Some worms burrow into the mud to avoid the heat
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What are the feeding relationships in freshwater ecosystems?
Producers are the base of all food webs. Algae and plants.
Consumers eat other organisms in a food web. Primary consumers such as snails eat producers.
Secondary consumers, like birds and many fish, eat primary consumers.
Tertiary consumers, like large fish and grizzly bears, eat secondary consumers.
A parasite-host relationship is another feeding relationship. The parasite takes energy and nutrients from the host’s body. Some flatworms are parasites that infect snails
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How do freshwater organisms compete with one another?
Bank swallows and trout are predators that compete for insect prey.
Snails and mayfly larvae compete for algae.
Freshwater organisms can also compete for abiotic factors, such as sunlight or space on rocks. Organisms of the same species can compete with each other for mates
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What are marine ecosystems? What are the three types?
saltwater ecosystems
Coastal ocean
examples include: Sandy beaches, rocky shores, and coral reefs
Open ocean
found over very deep water
Deep ocean
deepest, darkest parts of the ocean (ie ocean floor)
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What abiotic factors affect marine ecosystems?
Temperature, pressure, water depth, water flow rate, light levels, salt levels, and oxygen levels
For example, highlight levels in the shallow waters of coral reefs can cause highwater temperatures in these ecosystems.
The absence of light in deep ocean ecosystems causes them to be dark and cold, and the extreme depth leads to high pressure
The movement of waves near coastlines can change water depth and temperature in ecosystems on beaches and rocky shore
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Where can ocean ecosystems be found?
Coastal ocean ecosystems are found along the edges of continents and islands and include beaches, tidal pools, seagrass beds, coral reefs, and kelp forests.
Open ocean ecosystems are located in waters away from the coast.
Deep ocean ecosystems are found as far down as 11,000 meters under the sea
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What are coast ocean ecosystems like and where are they found?
Beaches, tidal pools, and seagrass beds are coastal ocean ecosystems that are most affected by tides and waves.
Coral reefs and kelp forests are underwater coastal ocean ecosystems. Coral reefs are found mainly in shallow, tropical coastal waters. These nutrient-rich ecosystems provide shelter and food for many species.
Kelp forests are found mainly in cold, nutrient-rich coastal waters. Kelp is a kind of seaweed. It provides food and shelter for sea otters, octopuses, and many fish species
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What are the three layers or zones of open ocean ecosystems?
The sunlight zone is near the surface of the open ocean.
The twilight zone is deeper and has less light.
The midnight zone is even deeper and darker.
Floating producers called phytoplankton live in the sunlight zone. Phytoplankton can be eaten by zooplankton, which are tiny floating animals. Plankton are an important food source for many open-ocean animals.
Flying fish, bluefin tuna, ocean sunfish, blue sharks, and some dolphins are true residents of the open ocean.
Other animals, such as herring, move between coastal and open ocean ecosystems.
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What are deep ocean ecosystems like?
completely dark, under high pressure, and often very cold. Water temperature can be close to 0°C in some deep places.
Because of the lack of light, no photosynthesis happens in these ecosystems. Organisms in the cold, deep ocean cannot get energy from living producers. They must have adaptations to get energy in other ways.
Sea cucumbers and brittle stars feed on organic matter that floats down from higher ocean layers. Anglerfish have adaptations that allow them to produce their own light to attract prey.
Hydrothermal vent ecosystems are also found in the deep ocean. The water around these ecosystems is very hot. because it's heated by molten rock from Earth’s interior. This water contains hydrogen sulfide, which bacteria can use to make food.
Vent bacteria have a mutualistic relationship with giant tubeworms. The tubeworms provide shelter for the bacteria. The bacteria produce substances the tubeworms can use for energy.
Giant clams, Pompeii worms, and some snails and shrimp also live in hydrothermal vent ecosystems
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What are the feeding relationships in a marine ecosystem?
Algae are producers in coral reefs and other marine ecosystems. Single-celled algae often belong to floating phytoplankton communities. Multicellular algae and algae that grow in colonies can look like plants. All types of algae use photosynthesis to make food.
Coral reefs are made of hard materials secreted by colonies of coral. Coral are animals, so they are consumers.
Coreal are primary consumers because they can get energy from algae. They are also secondary consumers because they eat zooplankton.
Parrotfish and sea turtles are other primary consumers in a coral reef (eat algae, plankton)
Groupers are others secondary consumers.
Reef sharks are tertiary consumers that eat secondary consumers like groupers.
Parasites: nematodes get shelter and food from the grouper’s body. However, these parasites can cause the fish to become weak and eventually die
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How do marine organisms compete with one another?
marine organisms of the same species may compete for food, space, or mates. For example, reef sharks may compete with each other for fish.
Members of different species can compete for resources. Different algae species may compete for sunlight and space to grow on a coral reef. Different marine animals may compete for food
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How do humans use oceans?
recreation and sport, food, raw materials (fertilizer for crops), minerals, additives for food, energy resources, such as oil and gas
tides and waves provide alternate forms of energy, like wind turbines, which produce wind energy that can be used to generate electricity
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How do human activities affect marine ecosystems?
Human activities on land can affect ocean organisms; for example, run-off is water that moves over land and eventually enters oceans.
from farms can carry pesticides and fertilizers.
from cities can carry oil and gasoline
Pesticides, oil, and gasoline can harm marine organisms
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What is overharvestingb?
when rates of fishing are higher than the rate of reproduction in a population; overharvesting can cause a population to disappear
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What are ways humans can help conserve marine ecosystems?
eating only fish that are not overharvested
reduce the use of chemicals, properly dispose of oil
governments pass laws to reduce overfishing and pollution
build artificial ocean reefs
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What is an artificial reef?
a human-made structure that is sunk into a coastal ocean area
