Climate Change
Which is a stronger greenhouse gas, molecule for molecule, carbon dioxide or methane
Methane (CH4)
What is the name for the band of atmospheric convection generally around the equatorial region, although not stable?
Intertropical Convergence Zone.
What is the difference between lithogenous, hydrogenous, and biogenous sediment?
Lithogenous: Derived from preexisting rock material (SiO2 chemistry) from erosion, volcanic eruptions, and wind-blown dust.
Hydrogenous:
hydro = water, generate = to produce
- Inorganic carbonates: ooids and oolites,
inorganic carbonate precipitates
- Evaporites: halite, anhydrite, gypsum
production from the evaporation of
seawater
- Ex: Manganese modules
Biogenous: bio = life, generate = to produce
- Derived from the hard parts of once living
organisms
What is unique about the water molecule in terms of polarity?
What is a hydrogen bond and how does that influence the physical properties of water?
-The overall bent geometry of the water molecule gives a slight negative charge to the oxygen side, giving the entire molecule electrical polarity (dipolar)
-In water, the positively charged H bonds with the negative charged O to form hydrogen bonds
-Hydrogen bonds are weaker than covalent bonds but strong enough to generate surface tension
What drives the flow of surface currents vs. deep currents?
BONUS: What is unique about the Antarctic Circumpolar Current?
Surface ocean currents: wind-driven currents
Deep Ocean Currents: Density driven currents
BONUS: Only current to encircle globe
How are computer models used in paleoclimatology?
To try to estimate climate change in the future.
What are sunspots? Over the last 400 years, do sunspots changes relate to any known change in climate events (or how are they related to global climate)?
Who is Wallace Broecker and what did he contribute to Oceanography that changed the scientific world in 1991?
He developed the idea of a global ocean conveyor belt linking the circulation of the global ocean.
What drives the changes in the seasons between the northern and southern hemispheres?
What is Albedo? What is the albedo of snow versus blacktop?
Global Tilt causes Earth’s Seasons
Albedo: The percentage of incidence radiation this is reflected back to space
Snow has high albedo and blacktop has low albedo.
Put the following in order of first to last to precipitate from evaporating seawater.
Gypsum, Calcite, K& Mg salts, Halite
Calcite, Gypsum, Halite, K&Mg salts.
What is the difference between positive and negative feedback? Give an example of each
Positive feedback: factors that amplify the rate of a processes
Ex: Sea Ice Melting
Negative feedback: factors that decrease the rate of a process
Ex: Build up of clouds reflecting solar radiation back into space.
What is the Global Warming Potential (GWP) of a gas?
What is the scale relative to? Which gases have the highest vs. lowest GWP?
- The Global Warming Potential (GWP) expresses the warming effect of an atmospheric gas over a set time period relative to CO2
- Lowest to highest GWP:
CO2 (1)
CH4 (25)
NO (265)
CClF2 (10,200)
What are the three specific, basic relationships for how temperature, salinity, and pressure are related?
Temperature increase = Density decrease
Salinity increase = Density increase
Pressure increase = Density increase
What is the difference between turbidity and contour currents (perpendicular or parallel to bathymetric lines?)
What forces drive their flow, and what is the name of their sedimentary deposit?
Turbidity Currents are great masses of sediment-
laden water flowing downhill under gravitational
forcing, they carve submarine canyons
- Flow is perpendicular to the bathymetric lines
sedimentary deposits: Turbidites
Contour Currents flow parallel to the
bathymetric lines, typically on the
continental slope
Driven by the Coriolis effect
sedimentary deposits: Contourites
How is hurricane activity likely to change this century from atmospheric CO2 loading from humans (hint: compare and contrast intensity vs. frequency)?
The frequency will likely stay the same (or decrease) while intensity has been and will likely continue to increase.
What and when was the Medieval Warm Period? Little Ice Age?
Little Ice Age: global ~1°C cooling from
1400 AD to 1850 AD
Medieval Warm Period: global ~1°C
warming from ~900 to 1400 AD
What are the three main cycles of Milankovic Cycles (name and time?)
Eccentricity: Earth's orbit around sun is elliptical (100 to 400k year-long cycles)
Obliquity or Axial Tilt: Earth's axis varies in tilt from 22.1°to 24.5° (41,000-year cycle)
Procession: Earths axis of rotation wobbles through time in response to the gravity of the sun and moon (23,000 year cycle)
What are the order of minerals on the discontinuous series of Bowen’s Reaction Series, from high to low
temperatures?
(Pyroxine, Biotite, Amphibole, Olivine)
Olivine, Pyroxine, Amphibole, Biotite.
What are the five silicate structural arrangements?
Isolated, Single-Chain, Double-chain, Sheet Silicates, Framework.
What igneous rock has a glassy texture? What igneous rocks have a vesicular texture?
BONUS: What causes an igneous rock to have a glassy texture?
BONUS 2.0: What are the other two igneous rock textures?
Obsidian
Scoria and Pumice
BONUS: Rapid cooling
BONUS 2.0:
Fine-grained = aphanitic
What are the 4 types of paleoclimate archives, and how do they store information (or how do we use them to learn about past climates)?
ice cores: Bubblespreserve previous atmosphere composition (CO2, CH4)
sediment records: sediment chemistry, texture,
microfossils & their geochemistry (e.g., foraminifera, pollen) can reconstruct salinity, temperature, pH, sea level, ocean circulation, etc.
corals: The geochemistry of the calcium carbonate layers can be used to reconstruct seawater temperature & salinity through time
tree rings: Can examine wood physiology and
chemistry to understand past climate on land when the tree was growing
What are the three primary components of Earth’s energy budget?
What part of the earth’s energy budget is impacted by greenhouse gasses?
1.1 Incoming solar energy (shortwave radiation)
1.2 Outgoing longwave radiation.
1.3 Earth's internal heat sources and other small effects.
Greenhouse gases decrease the outgoing radiation, which causes the retainment of heat.
What are the seven key steps in the Wilson Cycle?
Stage A: Stable Craton
Stage B: Early Rifting
Stage C: Full Ocean Basin
Stage D: Subduction Zone
Stage E: Closing Remnant Ocean Basin
Stage F: Collision Orogeny
Stage G: Peneplained Mountain
Who is credited with first suggesting continental drift, what evidence did he have, and what the problem with his theory?
- Proposed by Alfred Wegner from
1913-15
- Fossil Evidence and Glacial Evidence
- Wegner suggested that the driving
the mechanism was a combination of
the centrifugal force from Earth’s rotation
& the gravitational forces that cause
tides
(Physicists calculated these forces to
be insufficient)
What were two major contributions to the Theory of Plate Tectonics made by John Wilson?
- In 1965, Wilson proposed “transform faults”
in a Nature paper to describe plates slipping
past one another (e.g., San Andreas fault)
- In 1966, Wilson linked seafloor spreading
with land geology in a seminal Nature
publication.