Earth Science: Weathering, Erosion, Climate Change, and Biodiversity
- Earth is not quite as spherical as
a. the equatorial radius is a little larger than the polar radius.
2. Cryosphere includes:
o All forms of frozen water
3. Biosphere includes all of the following except:
o Atmosphere
4. Perihelion occurs in the Northern hemisphere (in January)
o Winter
· The seasons are caused by
o The tilt of the Earth’s axis
· On December 22nd the noon sun is directly overhead at
o 23.5° S
· The midnight sun or 24-hour daylight occurs on June 22nd
o North of the Arctic Circle
· The location of the Earth’s orbit where it is furthest from the sun is called
o Aphelion
· In mid-June parts of Alaska receive more insolation at the top of the atmosphere than parts of Florida. This is explained by:
o The daylight hours are much longer in Alaska
· In the Northern Hemisphere summer, the length of daylight increases
o From the equator poleward
· The amount of solar radiation reflected off a surface is called:
o Albedo
· Greenhouse gases are most efficient at absorbing ________ wavelengths of energy?
o Infrared
· Which is not a greenhouse gas?
o Nitrogen
· Earth’s radiation to space is mostly in _______ wavelengths
o Infrared
· Global net radiation is?
o Positive in the tropics, negative in the polar regions
· The two most abundant gases in the atmosphere are?
o Oxygen and nitrogen
· The ozone layer is important to life because
o It absorbs ultraviolet radiation (powerful)
· In a surface anticyclone, the upper-level air
o Sinks and diverges at the surface
· The Coriolis effect is caused by?
o Earth’s rotation
· Surface air converges and rises where?
o A cyclone
· In the Hadley cell, sinking air takes place around
o The subtropics
· The monsoon portions of Southern Asia (India) receive most of their precipitation during
o Summer
· The polar jet stream is located
o Near the tropopause around 60° latitudes
· Surface ocean currents are driven mainly by?
o Surface winds
· Deep ocean currents are driven by?
o Density differences
· The densest water has
o Cold temperature and high salinity
· During El Niño events, the _______ equatorial Pacific Ocean is unusually warm
o Western and central
· During La Niña, the trade winds are
o Stronger than normal
Midterm 2 (some of these are paraphrased, and I missed some because he started going through them very quickly)
Heat is released to the environment when water vapor changes into liquid. This process is called:
o Condensation
When snow melts and refreezes in cold air before reaching the Earth’s surface, it is called
o Sleet
Heat is absorbed from the environment when ice changes into liquid water
o Absorbed from
Today we are living in an … period of time
o Interglacial
Evidence of climatic variation prior to instrumented data is called
o Proxy data
Which of the following has been influenced by human activities?
o Atmospheric concentration of CO2, changes to surface albedo, atmospheric GHG concentration
o (All of the above)
The Milankovitch cycles explain long-term natural climate variations based on
o Earth’s orbital cycles
The record heat and drought in 2012 are good evidence of
o None of the above
Burning vegetation can
o Change surface albedo, water balance, and add GHG to the atmosphere
What evidence helped scientists understand the physical properties of Earth’s internal structure?
o Seismic waves
What determines the speed of seismic waves?
o Density of the material it is passing through
The internal layer of Earth that is responsible for allowing the lithospheric plates to move along
o Asthenosphere
The Mohorovičić discontinuity or Moho
o Is a sharp density change in Earth’s interior, is a contact plane between the crust and mantle, helped scientists determine the thickness of Earth’s crust
o (All of the above)
Crust is neither created nor destroyed at this boundary
o Transform boundaries
The oldest oceanic crust can be found
o Near the continents
Subduction zones are found along
o Where tectonic plates are converging
Mid-oceanic ridges are located where molten material flows from the mantle upward and solidifies at the surface
o True
Which of these is NOT a landform?
o Rocky Mountains
The most effective and significant agent of erosion is
o Running water
Runoff water moving over the land surface occurs when infiltration rates exceed the amount of water falling
o False
Which of the following holds the greatest amount of freshwater?
o Glaciers and ice sheets
The lower zone in the ground in which all the pores are filled with water is termed:
o Saturated zone or phreatic zone
Which of the following are components of soil?
o Organic matter, inorganic matter, gases, water
A soil profile shows a sequence of layers called
o Horizons
The decomposition of soil organic matter releases CO2 to the atmosphere
o True
Percentage of ocean and freshwater on Earth
o Ocean 97% and fresh 3%
Blue Book Questions and Answers Exam #2
1) a. Explain the main difference between weathering and erosion
B. Please describe briefly two examples of weathering and two examples of erosion
Weathering: mechanical, chemical, biological
Erosion: Mass movements (landslide, mudslide), Running Water (abrasion, corrosion), Glacial (plucking, abrasion), wind, waves
2) Give an example of a natural internal, one example of a natural external, and one example of an anthropogenic climate change process
External: Changes to Earth’s orbit
Internal: Changes of climate (atmosphere, hydrosphere, etc.)
Anthropogenic: Pollution, land use land cover (deforestation, desertification)
Describe at least 2 processes in how deforestation can enhance global warming
Global Impacts: Less CO2 taken by vegetation during photosynthesis, more CO2 released by decomposing trees
Local Impacts: Increase albedo, changes in surface roughness, change in latent and sensible heat exchange, changes in soil water balance, increased diurnal temperature range because the shading effect is removed
3) Name the layers of Earth’s interior structure starting with the innermost one
Solid inner core, liquid outer core, mantle, crust
Provide 2 pieces of evidence for continental drift
Fossils in two places across continents, continents fit together like puzzle pieces, ocean floor ridges show where it used to be
4) Triangle thing: Start on the bottom with sand then go clockwise
Explain why regions with poor soils are able to support a lot of vegetation, like rainforests
Oxisoils = low fertility soils due to excessive rainfalls which leach the nutrients from the soil, so it has nutrient-poor soil
Rainforests have trees because nutrients are held in the biomass and topsoil, the plants are adapted to low nutrient levels, and the rainforest soils are not suitable for crop production.
What is the circulation pattern around a surface low-pressure center in the Northern and Southern Hemispheres?
A) Draw diagrams to illustrate these circulation patterns.
B) What are the forces responsible for these wind patterns? A) Northern hemisphere, it’s moving anticlockwise towards the centre; southern hemisphere it’s moving clockwise towards the centre
B) Near the surface the forces responsible for the wind circulation are pressure-gradient, Coriolis, centrifugal, and friction forces
Draw a diagram to illustrate the Hadley cell circulation. Your diagram must include the high and low pressure centers, the convergence and divergence zones, and the rising and sinking air locations. Look up in the midterm 1 lecture
Explain the three processes by which heat can be transferred. Please give at least two examples of each process. Radiation: transmission of heat through electromagnetic waves; examples – solar heating, room heater, microwave oven
Conduction: transmission of heat by contact between molecules; examples – soil warming/cooling, icepacks, stovetops, seat warmers
Convection: transmission of heat by the movement of fluids; examples – atmospheric warming, thunderstorms, clouds, convective oven, warming water in a pan, hot air balloon
In Springfield, the surface air temperature is 30°C and the environmental lapse rate is 7.5°C/1,000m.
A) If a surface air parcel is lifted following a dry adiabatic lapse rate (10°C/km), what is the air parcel temperature at 2,000m height?
B) Is the air parcel stable or unstable at 2,000m? Why? A) 10°C
B) Parcel is stable because it is colder than the air around it
A) Explain the main difference between weathering and erosion
B) Please describe briefly two examples of weathering and two examples of erosion A) Weathering -> breakdown of rocks in place (no transport); sets the stage for erosion by bringing about the disintegration of rocks
Erosion -> the other types of breakdown processes that includes transportation; transports sediments from disintegration away
B) Weathering
– Mechanical: water freezing, water evaporation, temperature changes
– Chemical: carbonation, oxidation, hydrolysis
– Biological: organic acid produced by microorganisms, root growth, etc.
Erosion
– Mass movement: landslides, mudflows, debris flow
– Running water: hydraulic action, abrasion, corrosion
– Glacial: plucking and abrasion
– Wind: suspension, saltation, and creep
– Coastal waves: wave impact and air pressure in rock cracks
Weathering by temperature changes: temps changes cause cracks on rocks which eventually results in rock breakup
Weathering by carbonation: water and CO2 combine to form carbonic acid which corrodes some types of rocks
Erosion by running water: running water erodes the sides and bottom of stream channels
Erosion by landslide: movement of soil often related to excessive rainfall
A) Please give one example of a natural internal, one example of a natural external, and one example of an anthropogenic climate change process
B) Describe at least two processes, either local or global, by which deforestation can enhance climate change A) External causes: changes to the Earth’s orbit and solar output
1. Changes to Earth’s orbit (Milankovitch cycles)
2. Changes to the Sun (solar output)
Internal causes: natural changes in the major components of climate
1. Plate tectonics (distribution of land and water on Earth)
2. Volcanic eruptions (greenhouse gases and ash emission)
3. Natural changes to the ocean currents
Anthropogenic causes:
1. Deforestation
2. Fossil fuel burning
3. Vegetation burning
4. Land use change
B) Deforestation reduces the amount of CO2 removed from the atmosphere through photosynthesis therefore enhancing global warming. Also deforestation decomposing dead tree release CO2 to the air
1) Global impacts
a) Less CO2 sequestered by vegetation during photosynthesis
b) more CO2 released via burning and decomposition of dead trees
2) Local impacts
a) increased surface albedo
b) changes in surface roughness
c) changes in latent and sensible heat exchange
d) changes in the soil water balance
e) increased diurnal temperature range because the shading effect of the forest canopy is removed.
A) Name the main layers of the Earth’s interior structure starting with the innermost one.
B) Please provide 2 evidences that support the concept of continental drift. A) Based on seismic wave analysis and other evidences, Earth is believed to have 4 major layers: solid inner core, liquid outer core, mantle (upper and lower), crust
B) Fossil records show that same species once lived in Africa and South America; earthquakes and volcanic eruptions are caused by the continental drift; mid-oceanic ridge or continental mountain ranges; different rock ages that form the ocean floor
A) Using the soil texture triangle below, please determine the soil type based on the percentages:
40% silt, 20% clay, and 40% sand.
B) Explain why despite being located in regions of poor-quality soils, rainforests are able to sustain diverse and dense vegetation. A) Loam
B) The nutrients are held in the biomass and topsoil (trees roots, decomposing matter), and the rainforest plants have adapted over time to this environment.
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Sources
Processes That Can Reduce Carbon Uptake By The biosphere
1. Deforestation— Reduces Photosynthesis—- Carbon source
2. Vegetation burning—release Carbon That The Plants Had Absorbed When They were alive—- Carbon source
3. Cultivation Of soil—accelerates Soil decomposition And Increases Carbon release— Carbon source
Sinks
Processes That Can Increase Carbon uptake
1. Secondary succession
a. Regrowth Of Forests On Farms and pastures
2. Carbon fertilization effect
. CO2 May Act As a “fertilizer”
Carbon budget equation as seen in class
sources–sinks = reservoir changes
Land release= 120PgC—source
Ocean release = 90PgC—-source
Land uptake= 122PgC—-sink
Ocean uptake = 92 PgC–sink
+8.0 + 0.9 – 2.0 – 2.0 = +4.9PgC per yr
8- fossil fuel burn
0.9 Deforestation
2 Net land uptake
2 Net ocean uptake
Be able to:
1. Describe the main sources and sinks of carbon in the Earth system
2. Explain the role of photosynthesis and respiration in the carbon cycle
3. Explain how fossil fuel burning and land use change contribute to atmospheric carbon budget
4. Calculate the average annual change in atmospheric carbon
5. Describe ocean acidification
- The ocean removing CO2 From the atmosphere.
- CO2 absorbed by the ocean is changing the chemistry of the seawater
6. Explain how rock weathering removes carbon from the atmosphere
- Carbonation Occurs When carbon Dioxide (CO2) From Atmosphere Or Within The Soil Dissolves In Rainwater To Form An Mild Acidic Solution Called Carbonic acid
- Carbonic acid dissolves or breaks down minerals in the rock. For Instance, limestone(CaCO3)
7. Differentiate long-term and short-term carbon cycle components
- Long
- Removal of carbon through rock (chemical) weathering
- Absorption of carbon by marine Organisms To Make shells and skeletons (sedimentation process)
- Converging tectonic plates move carbon down into the subduction zone. Carbon is released at mid-oceanic ridges as new rock material is brought upward
- Short
- Removal of carbon through the ocean surface and atmosphere exchange
- Photosynthesis
- Respiration and decomposition
- Anthropogenic sources
Week 14: Biodiversity and conservation
Keywords:
Biodiversity
Refers to the variety of plants and animals species in a given area, ecosystem or biome
Species geographical range and habitat
- Where species live
- Physical limiting factors
- Temperature
- Availability of water
- Other climatic factors
- Distribution of soils
- Landforms
Optimum range,
in which a species is at its best survival and reproduction level
zones of stress
a species increasingly finds zones of physiological Stress where it can still survive but in small populations
Zone of intolerance
When conditions become even worse
Competition,
Refers to the competition between species for resources such as food, space, light, or water
Predation,
individuals of one species feed on another species
Amensalism,
an interaction where an organism inflicts harm to another organism without any costs or benefits received by itself.
Mutualism
Biological interaction in which individuals of two species interact to their mutual benefit
Ecological niche,
the environmental space within which a species Operates most efficiently or to which it is most effectively adapted.
disturbances,
Disturbances are the starting point for secondary succession
Examples: wildfires, deforestation, hurricanes, diseases
endemic species
- Movement of land
- For example, Madagascar was originally part of Africa and so the same species are found on both a
can also affect species range
Adaptation by natural selection
- Adaptations allow species to survive under environmental changes.
- Natural selection stems from reproductive processes
- Not all individuals of a population will pass their genetic information
to the next generation.
- Natural selection process Is responsible for all the Adaptations to environments.
Species conservation and biodiversity hotspots
Hotspot strategy concentrating conservation efforts and funds on a relatively small number of highly vulnerable ”hot spots”
Be able to:
1. Explain the main physical factors can control species range
2. Define competition, predation, amensalism, and mutualism
3. Explain species dispersal and endemic species
- species dispersal
- Physical and biotic factors determine the natural range of plant and animal species
4. Describe natural selection and adaptation
5. Differentiate between endangered and threatened species
- endangered
· species in danger of extinction throughout all or a significant portion of its range
- threatened
- a species that is likely to become endangered in the foreseeable future.
6. Describe why there may be an on-going (sixth) mass extinction
- The past 400 years have seen 89 mammal species extinctions, and 169 species are now considered critically endangered
- This is 45 times the predicted rate based on mass extinctions
7. Explain the impact of human activities on biodiversity
- and use change Is the primary driver of species loss
- Overall, 35% to 50% of the Earth’s Land cover have been altered
8. Comment on species conservation and biodiversity hotspot
9. Why should we try to conserve species?
- Promote biodiversity
- biodiversity is essential for a healthy and Functional ecosystem (trophic levels).
- Beneficial for humans
- one can learn a lot from animal and plant species which can benefit the human race (medication, resins, etc)
- Ensure a healthy ecosystem: conservation of ecosystems helps maintain stable soil and land cover, which have direct impact on erosion and water cycle