2270 Flashcards
What is the difference between weather and climate?
Weather is the day to day observations of weather.
Climate is the the long term averages of weather.
What are the atmospheric layers
Troposphere
Stratosphere
Mesosphere
Thermosphere
What are the boundaries between each sphere?
tropopause
strtopause
mesopause
What is the most abundant element in the atmosphere
nitrogen
What is the driving force of atmospheric circulation
the sun
What level of the atmosphere contains the most gas
troposphere
What atmospheric layer contains the ozone
strotosphere
Why is it interest that water vapour is naturally occurring in the atmosphere
it is a GHG
Where on the earth has the highest insolation potential?
Equator
Why is there ore insolation along the equator?
Due to earths spherical shape
What is solar irradiance
whereby equal amount of solar radiation is hitting earth, but heat is concentratied on smaller area at centre than at poles
Define convection
movement of heat from one place to another by movement of air - E.g. room analogy
Why can’t a one-convention cell theory be applied to earths surface?
Not smooth, not continuous, and spinning motion
Coriolis effect
Rotation causes movement to the right in N and moment to the left in S
How does the Coriolis effect impact atmospheric circultion
3-cell model
Hadley 0-30
Ferrel Cell 30-60
Polar 60-90
Cells impact movement of wings
Global wind belts - in North move to the right
In south move to the left
Science checklist
- focuses on natural world
aims to explain natural work
uses testable ideas
relies on evidence
The Scientific Method
Pragmatic - using wide variety of testing tactics continuous process of refinement 1. Identify problem 2. form hypothesis 3. test helpothesis/make observations 4. etc.
Define Law
general statement about expectation that certain events will occur where certain conditions are met (e.g. law of gravity)
Hypothesis
Human mental construct thet provides preliminary casual explanation of facts
Theory
more complex and wide-ranging mental construct
T/F Science IS about absolute truths
False
Peer Review process
- research writes publications and submits to peer-reviewed journal
- editor decides if publication is good enough
- Sent to a few reviewers to read and write for recommednations
- Can accept/reject/ask for revisions
- Paper back to author and author applies revisions
- editor makes final decision
What is the invisible boot?
Process by which peer reviewed process kicks out ideas that don’t work
Ozone Hole
Apparent that ozone holes were forming
Chemical that was found to be the culprit - CFCs (aerosol cans)
scientists were able to connect these results to other studies to determine relationship between Ozone and CFCs
Corelation does not equal causation
E.g. global average temperature and number of pirates
IPCC
Intergovernmental Panel of Climate change
UN in 88
Assess state of scientific knowledge on climate by regularly reviewing scientific literature and create assessment reports
What are the 3 volumes for the IPCC Assessment Reports?
- The Physical Science Basis
- Impacts, Adaption and Vulnerability
- Mitigation of Climate change
Thousands of scientists from all over the world contribute their results to the IPCC
True
Structure of a atom
contain small nucleus that contains protons (+) or neutrons (neutral) and electrons (-)
atomic number
element number referring to number of protons
atomic mass
number of protons + number of neutrons
Isotopes
Atoms of the same atomic number but differing mass
X vs Y axis
| = y _ = x
temperature Anomaly
difference between measured temperature of a year and its baseline period
How do scientist estimate average global temperatures
Divide earth into grid cells (lat and long)
obtain temperature measurements in each grid box to create averages
Add averages - need to correct for earth geometry (small near poles large near equator)
Weighted average
Problem associated with estimating average global temperatures
earth geometry
and lack of data in many areas in the world
How do satellites measure temperature
air temp of lower troposphere using microwave sound units
How do air balloons measure temp
radiosonde transmits temp info to reciever
Different data sets used for averages demonstrate differences
Difference: how datasets deal with having little data in remote parts of the world, size of grid, etc.
What is the most comprehensive coverage for data sets
NASA Goddard Institute
16 od the 17 warmest years on record occurred during the 21st centruy
True
Keeling curve
Telling - reported CO2 every day in Hawaii since 60s
Human finger print - 13C and 12C
Isotope = same number but different mass stable C (12/6 or 13/6) unstable 14/6 C = radioactive
Most of the CO2 in atmosphere is stable - easier for plants to assimilated 12C (light/smaller)
plants die - decompose - formed into fossil fuels
Burn fuels, adding more 12CO back into atmosphere which is directly a result of human burning of fuels
What greenhouse gases are increases
Methane, CO2, Nitrous Oxide, CFCs
methane
Powerful GHG and increasing due to agricultural (rice paddies and livestock)
What are main human causes of GHG emissions
Agriculture
Biomass burning
Livestock
Coal mining
What are the two stable C02
C12 and C13
What indicates that excess CO2 in atmosphere comes from burning fossil fuels
smaller C13/C12 ratio
Give examples of human finger prints
- decrease of 13c/12c ratio
- stratosphere cooling because less heat is leaving troposphere to heat it
What indicates that cooling of stratosphere is human causes
GHG trap heat and keep it in troposphere
Define paleoclimatology
research that examines past climates
Climate proxies
natural archives of the climate
Give examples of climate proxies
Tree rings pollen lake sediments ice cores corals stalagmites
How do tree rings indicate climate change
tree growth rates
width of ring are sensitive to the climate
The thicker the ring = the better the growing conditions
How to ice cores indicate climate change
800 000 years old
Thickness of layers, presence of ash and dust, air bubbles that contain C02
oxygen isotope chemistry
What makes a isotope stable
Has more neutrons than protons (heavier)
water isotopes
2H or 18O = heavy water
Heavy water evaporates less easily but condensates more easily
different temperatures lead to different stable isotope ratios
What does presence of heavier ice
WARMING
What does the presence of lighter ice
COLDER
How does pollen in Lakes identify climate change
Reconstruct vegetative history
Plants can only occur in certain climate conditions
E.g. sage - cold and dry
E.g. okay - warm and dry
Why use different climate proxies?
Provide different climate information (e.g. precipitation, temperature, etc.) and have different timescales
Define resolution
smallest quantity of time for which information can be extracted from proxy
Define timespan
total amount of time a climate proxy can provide
Explain carbon dating
14C - unstable therefore decaying over time
Decaying at stable rate
Measure how much 14C is left, tells us how long its been dead for
Less 14C = longer its been dead
What does coral growth depend on
water temperature
What is the most commonly used proxy
Ice cores
Dendrochronology
Count tree rings
Milankovitch cycles
Intensity of radiation from sun vairies according to 3 cycles:
- obliquity - tilt
- Eccentricity - shape
- Precession - wobble
Relate milan. cycles to climate change
ice ages occur when orbital variations to cause lands to receive less sunshine in summers
What is a positive feed back?
Increased warming from solar irradiation has led to warming oceans
warmer oceans cannot hold as much C02, therefore more CO2 is released into atmosphere and perpetuates warming
What is a negative feedback
E.g. Younger Dryas - increased warming - increased melting of ice - increased fresh water - diluting saltiness of waters and stopped circulation which created intense cooling
What is THERMOHALINE CIRCULTURE
Convery belt transporting heat
P.A.I.N. Explanation
Personal
Abrupt
Immoral
Now
Need to meet all these things to be taken seriously
largest emission source
Burning of fossil fuels
- deforestation
- agriculture
Scenarios that determine future GHG emissions
Economic growth
Population size
technological development
social will
What are the differences between each climate scenario
A - focus on comic growth
B - focus on environmental integrity
What is RCP
Each has expected CO2 concentration as of 2100
Increased concern for environmental issues; low population growth; slow economic development; emphasis on local solutions to economic, social and environmental sustainability.
B2
High level of environmental consciousness; global population peaks in mid-century and then declines; moderate economic growth; economy focused on clean and resource efficient technologies
b1
Uneven economic growth; continuously increasing population; emphasis on self-reliance and local identities.
a2
What do we use so many models
- limits due to computer speed
- potential trade-offs
How can you test how good a model is
run the model backward to see its validity
What is the relationship between climate and scenario model
scenario models calculate future GHG emissions - these calculations are used in climate models
Findings of current IPCC report
- atmosphere and oceans warmed
- sea level rising
- GHG emissions increased
- Lossing icesheets
how many meters does the melting of Greenland icecsheet have the potential to raise sea level
5-7 meters
What are the deadly trio
ocean warming
ocean acidification
and ocean anoxia
coral bleaching
Ocean warming is greatly affecting oxygen content in algae,
Corals eat algal but can’t process excess oxygen
Ocean acidification
Increased CO2 in atmosphere is being dissolved in waters increasing its acidification
impacting organisms such as sells
What is thermal expansion
seawater can expand to fill a greater volume of heat
Impacts of a rising sea level
- storms and flooding
- storms able to reach further inland
- changing coastlines
- salt water intrusion
Which pole is melting quiker
Arctic
What is saltwater intrusion
movement of sea water underground into reservoirs
Who are the first climate change refugees, and why
The Maldives - lowest country on planet
How will sea level rise affect canada
- extended flooding
- accelerating erosion
- saltwater intrusion
- impacts on wildlife
Which Canadian coasts are the most affected
Atlantic coast and beaufort
How much shoreline is lost when sea level rises 1 foot
300 feet
When would we see regular flooding every 28 days with sea-level rise
due to spring tides occurring every 28 days
when do we expect polar icecaps to be ice-free
next 20 years
Can we alter sealevels rising
Do to intense storage of heat in oceans now we will not be able to stop sea-level rise
What are mitigation tactics
decreasing sources: decreasing total GHG emissions
Increasing the sinks: finding ways to remove CO2 from atmosphere (carbon capture)
Bathtub analogy
Faucet=carbon sources
Drain= sinks of carbon
How can we lessen our demand for GHG: Demand-driven
Improve Energy Efficiency (E.g. Hybrid vehicles)
Improve every consumption (E.g. walking/ turning lights ogg)
Give example of a green building
Wendell Wyatt
60-65% less energy than regular
Energy efficiency dilemma
Energy efficiency increases with economic growth BUT GHG also increase
How can we lessen our demand for GHG: Supply-side
Renewable energies (e.g. wind turbines)
List some biomass sources
human sewage
corn and ag residues
food waste
Publicly, what is the most support energy source
solar
What are the benefits and challenges associated with alternative energy sources
Benefits: - reduced emissions -sustainable -easy distribution Cons - Cost - conflicts for land use - variable outputs (wind/sun)
How can we adapt to climate change
- migration corridors
- 50 million tree program
- green roofs
