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ISP 203 Exam 2
Global Change
93
Other
Undergraduate 2
11/02/2009

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Cards

Term
At what point in time did 60% of all species die out?
Definition
At the Cretaceous-Tertiary Boundary
Term
What are the impact results of a 10km diameter meteorite?
Definition
Blast Wave, vaporization of rock and water, earthquakes, tsunamis, global fires, global darkness, extreme cold, and acid rain.
Term
Name diferent types of meteorites.
Definition
Stony, Iron, and Stony-Irons.
Term
What are the two different types of stony meteorites?
Definition
Chrondites and achrondites.
Term
Where do meteorites come from?
Definition
The main source is from the asteroid belt between Mars and Jupiter but a few dozen also derived from the moon and mars and rarely derive from comets.
Term
What causes the formation of meteorites that come from the asteroid belt between Mars and Jupiter?
Definition
Collision and fragmentation shifts the orbit of some fragments out of the asteroid belt
Term
What causes the formation of meteorites that come from between the moon and mars?
Definition
They are most likely the result of an asteroid impact with the moon and mars, sending terrestrial material into space.
Term
What causes the formation of meteorites that come from comets?
Definition
As the comet gets close to the sun, it sublimates resulting in a cloud of diffuse and fine particles. Comets can split apart when affected by the sun's strong gravitational force.
Term
ABout how many new apollo objects are found each year?
Definition
35
Term
What will all earth-crossing asteroids eventually do?
Definition
Collide with the Earth
Term
How many impact craters our known on our planet?
Definition
174
Term
What is the closest large impact crater to Michigan?
Definition
The 1.8 billion year old 155 mile wide sudbury basin in Ontario, Canada
Term
What is the impact sequence of events?
Definition
Impact-Mass strikes the Earth and produces shock wave. Compression-SHock wave excavates and compresses material, vaporizing impactor and raising temperature of target rock. Decompression-compressed target rock rebounds.
Term
When did the First Primitive Atmosphere develop?
Definition
4.6-4.0 billion years ago
Term
What was a significant characteristic of the Firt Primitive atmosphere?
Definition
It was completely anoxic (lacking oxygen)
Term
When did the Secon Chemical/Premicrobal atmosphere develop?
Definition
4.0-3.3 billion years ago
Term
Why did the composition of the atmosphere change the first time?
Definition
Because of volcanic out gassing and perhaps impact degassing of left over planetesimals and cometesimals colliding with earth.
Term
What were the temperatures like of the second atmosphere?
Definition
Much higher than present temperatures because of high initial temperatures from accretion of planet impacts and also the high amount of carbon dioxide and water of the second atmosphere resulted in a considerable greenhouse effect
Term
When and why did the first oceans develop?
Definition
3.9-3.8 billion years ago during the second atmosphere when the atmosphere cooled enough for water vapor in the atmosphere to condense to form rain which collected in the ocean basins. the expanding ocean also served as a sink for much of the amospheric carbon dioxide
Term
Could life have existed during the second atmosphere?
Definition
Life could not have existed within 5M of the ocean surface or on the land because the atmosphere did not provide protection from ultraviolet radiation that disrupts the development of complex molecules such as those of living organisms
Term
When did the Third Microbal Atmosphere develop?
Definition
3.3-.4 billion years ago
Term
When and what were the first oxygen producing phototrophic organisms?
Definition
3.8-3.5 billion years ago procaryote cyanobacteria ("blue-green algae")
Term
What was the next step after oxygen producing organisms?
Definition
By 1.3 billion years more efficient eukaryotic cells ("green algae") evolved developing oxygen mediating enzymes which are a prerequisite for multicellular, advanced organisms
Term
What led to the formation of an ozone layer thick eough to shield plant life within 5m of the ocean surface from harmful effects of UV radiation?
Definition
slow buildup of free oxygen in the atmosphere during developmet of the thrids atmosphere
Term
When did the Fourth Modern Atmosphere develop?
Definition
400 million years ago
Term
What is today's atmosphere composed mainly of?
Definition
nitrogen, oxygen, and argon with some carbon dioxide, neon, helium, methane, and hydrogen
Term
What is the average thickness of Earth's atmosphere?
Definition
>82km or 50 miles
Term
What happens to Earth's atmospheric pressure with elevation?
Definition
It decreases exponentially
Term
What happens to earth's atmosphereic density with elevation?
Definition
it decreases
Term
What are the two characters of the sea floor?
Definition
oceanic ridges and abyssal plains
Term
What is the largest topographic feature on the earth?
Definition
mid-ocean ridges
Term
How are black smokers formed?
Definition
Hydrothermal vents within central valleys release hot sulfur rich solutions from volcanic rocks. The vents form meter-high dark mounds (black smokers) composed of metal-rich precipitates.
Term
Where do abyssal plains lie?
Definition
5-6km below the ocean surface and are underlain by fine sediment (mud)
Term
What sea floor characteristic form most of the ocean floor?
Definition
abyssal plains
Term
Hoe does the thickness of abyssal plains work?
Definition
The sediment thins towards the mid-ocean ridges and becomes thicker away from the ridges
Term
Types of continental margins
Definition
Passive continental margins, active continental margins, special environments
Term
What are passive continental margins characterized by?
Definition
continental shelves
Term
What occurs past the continental shelves?
Definition
continental slope
Term
What are active continental margins characterized by?
Definition
narrow to nonexistent continental shelves or by deep ocean trenches
Term
What is a characteristic of the special environments within the continental margin?
Definition
reefs
Term
What sort of reefs are associated with islands?
Definition
fringing reefs
Term
What sort of reefs are associated with continental margins?
Definition
barrier reef
Term
What sort of reefs are isolated and ring shaped and associated with guyots?
Definition
atolls
Term
Composition and properties of seawater
Definition
Gases, Salinity, Temperature, and Density
Term
What are gases in seawater made of?
Definition
Mainly oxygen and carbon dioxide
Term
Why is dissolved oxygen high in the photic zones?
Definition
Due to exchange with the atmosphere and photosynthesis by marine organisms
Term
Does oxygen increase or decrease with depth and why?
Definition
Decreases due to oxidation of dead organic matter.
Term
What doe soxygen do below the depth of 1km?
Definition
Dissolved oxygen increases due to convection (circulation) of oxygen rich cold waters from polar regions
Term
Why is carbon dioxide low in the photic zone?
Definition
Due to uptake by plants
Term
Does carbon dioxide increase or decrease with depth and why?
Definition
Increases due to decay of organic matter and high solubility of carbon dioxide in cold waters
Term
What is the average ssalinity of the ocean?
Definition
3.5%
Term
What is salinity in the ocean due to?
Definition
mainly dissolved Cl, Na, SO4 and Mg
Term
Where is the salinity of the ocean generally least and why?
Definition
Near the surface due to dilution by fresh water
Term
Does salinity increase or decrease with depth?
Definition
Increases
Term
What is the average temperature of the ocean?
Definition
6 degrees Celsius
Term
Does temperature increase or decrease with depth and what results from the change?
Definition
Decreases often resulting in a warm mixed surface layer 100-200m thick.
Term
What temperature lies beneath the surface layer?
Definition
A permanent thermocline of unmixed water  and a cold layer of unmixed water below that
Term
What is the range of density in the ocean?
Definition
1.024-1.027
Term
What is the density at high latitudes?
Definition
It increases to a depth of 300m and then remains generally constant.
Term
What does density do in low latitudes?
Definition
It increases to a depth of 2,000m and then remains constant
Term
What are some examples of surface ocean currents?
Definition
The north and south equatorial currents, the west wind current, the north pacific current, and the gulf stream
Term
According to the Coriolis and Ekman effects which way is the curviture in the northern and southern hemisphere?
Definition
In the northern hemisphere the curviture is to the right, while in the southern hemisphere it is to the left.
Term
When are reverse flows possible according to the Coriolis and Ekman effect?
Definition
At depths of 100m
Term
Examples of gyres
Definition
The north atlantic subtropical gyre, the north pacific gyre (Great Pacific Garbage Patch)
Term
What are deep-sea currents driven by?
Definition
Thermohaline circulation
Term
What causes the density of seawater to increase?
Definition
Cooling and freazing in the polar regions
Term
What causes the density of seawater to decrease?
Definition
High temperatures and large quantities of rainfall in the tropics
Term
What causes upwelling of cold waters elsewhere?
Definition
Sinking of polar waters displaces deep waters
Term
examples of deap-sea currents upwelling
Definition
North Atlantic deep water, antarctic bottom water
Term
How long does the cycle of upwelling take?
Definition
1600 years to complete
Term
What is the result of trade-wind currents weakening or reversing late in the year due to eastward shift of the low pressure cell?
Definition
Warm surface waters are transported eastward resulting in blockage of upwelling of cold deep water (El Nina) and high precipitation along coast of South America
Term
When do effects of El Nina extend far beyond the eatern pacific?
Definition
During periods of unusually well-developed blockage ( a strong El Nina event)
Term
Examples of El Nina effect
Definition
Drought conditions in Western Pacific, heavy rains in Western South America, Southern US and California, and warmer winters in Canada
Term
How do tropical cyclones originate?
Definition
As tropical depressions
Term
Where do tropical cyclones develop?
Definition
Along the boundary between the doldrums and the trade-wind belt
Term
Of the short-wave radiation intercepted by the Earth's atmosphere, what percent is reflected off air molecules, atmospheric dust, clouds, and the Earth's surface?
Definition
30%
Term
Of the short-wave radiation not reflected, what percent is absorbed by the atmosphere, mainly by ozone in stratosphere?
Definition
19%
Term
Of the short-wave radiation not reflected, what percent is absorbed by the atmosphere, mainly by the Earth's surface?
Definition
51%
Term
the amount of longwave radiation emitted from an object is a function of what?
Definition
its temperature
Term
What is the temperature of the Earth's surface and atmosphere dictated by?
Definition
The balance between incoming and out going radiation
Term
What type of radiation is mostly gained or lost at the Earth's surface?
Definition
Longwave radiation
Term
Is the heat capacity of liquid water relatively large or small?
Definition
Large
Term
Factors driving natural climate change
Definition
Atmosphere composition, plate tectonics, orbital variablilty, solar variability, and volcanic eruptions
Term
What doe spositive climate forcing lead to?
Definition
Global warming
Term
What does negative climate forcing lead to?
Definition
Global cooling
Term
What is atmosphere composition connected to?
Definition
Changes in concentration of greenhouse gases
Term
What is plate tectonics connected to?
Definition
Changes in Earth's surface albedo and ocean circulation
Term
What is orbital variability connected to?
Definition
Changes in received shortwave radiation
Term
What is solar variability connected to?
Definition
Changes in sunspot activity
Term
What are volcanic eruptions connected to?
Definition
An increase in the atmospheric albedo
Term
WHat are greenhouse gasses connected to?
Definition
An increase in atmospheric longwave radition from burning fossil fuels
Term
What are anthropogenic aerosols connected to?
Definition
An increase in atmospheric albedo from generation of air-born dust
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