Global Climate Change Flashcards
true or false
climate change only influences certain aspects around us
false - influences EVERYTHING around us
what does climate include (traits)
- temp
- moisture content
- wind
- precipitation
- pressure
- solar radiation
weather vs climate
weather
- specifies conditions at localized sites over hours or days
climate
- an area’s long term atmospheric conditions over seasons, years or millennia
what is included in global climate change
- temp changes
- precipitation changes
- storm frequency and intensity
global warming vs global climate change
global climate change
- trends and variations in earth’s climate
global warming
- specifically refers to an increase in earth’s average surface temp
is global warming an aspect of global climate change OR is global climate change an aspect of global warming
global warming an aspect of global climate change
what is largely responsible for climatic changes
human activities
- deforestation
- fossil fuels
- combustion
the three factors that influence earth’s climate more than all others combined
- sun
(without earth would be dark and frozen- provides earth’s energy) - atmosphere
(without earth would be almost 33 degrees Celsius colder- absorbs incoming solar radiation) - ocean
(shapes the climate by storing and transporting heat and moisture)
what supplies most of earth’s energy
sun
albedo
the reflectivity of a surface
where do GHGs warm
the lower atmosphere
how does earth’s surface interact with solar radiation
earth’s surface absorbs incoming short-wave solar radiation
surface materials emit longer-wave solar radiation (infrared radiation)
best gases in lower atmosphere that absorb infrared radiation
- water vapour
- ozone
- carbon dioxide
- nitrous oxide
- methane
- halocarbons
- CFS (Chlorofluorocarbons)
what are greenhouse gases
gases that selectively absorb infrared radiation released by earth’s surface and then warms the surface and troposphere by emitting INFRARED energy
greenhouse effect
Some of the re-emitted energy from the earth’s surface that is not lost to space instead travels back downward to warm the troposphere and earth’s surface
is greenhouse effect a natural phenomenon
YES
how is the greenhouse effect a positive process
our planet would have a much cooler surface temp without it = no life would be found
what part of the greenhouse effect is the problem
the human generated contributions is the problem NOT the natural process
how have human impacts negatively impacted the greenhouse effect process
Human activities have increased concentrations of greenhouse gases = enhances the greenhouse effect
Global warming potential
The relative ability of one molecule of a given greenhouse gas to contribute to warming that is measured against CO2
how do greenhouse gases differ from each other
- concentrations
- ability to warm the troposphere and surface
what GHG is of primary concern
CO2
why is CO2 the primary concern of the GHGs
may not be the most potent GHG on a per-molecule bases HOWEVER it is the most abundant gas in the atmosphere of any other GHGs
main natural source of carbon dioxide into the atmosphere
decay of organic matter
what is the link between GHG is atmosphere and temperature
high amounts of GHG in atmosphere = higher temp
how does the human source of carbon unbalance the natural process of carbon fluxes
Natural source of carbon may be higher than human source BUT the natural fluxes cancel each other out while the human sources do NOT have fluxes cancel.
how do human activities impact fluxes of materials
accelerates the fluxes of materials from one to another reservoir
is human fluxes or natural fluxes of carbon into atmosphere faster
human fluxes are faster
what are the 2 main reasons for increase in atmospheric CO2 concentrations since industrial revolution
- Release of carbon from long-term reservoirs (deforestation removes CO2 from terrestrial reservoirs to atmosphere)
- Acceleration of the carbon flux from lithospheric reservoir to atmospheric reservoir by burning fossil fuels
why is ozone important for life
it’s function in the stratosphere as a UV filter
what are halocarbons
anthropogenic group of chemicals
what is part of the reason for the stratospheric ozone depletion
halocarbons
what is the most abundant naturally occurring GHG in atmosphere
water vapour
what GHG contributes the most to the natural greenhouse effect
water vapour
has the global concentration of water vapor changed over recent centuries in atmosphere
NO
how is the concentration of water in atmosphere connected to temp
as the tropospheric temp increases, water bodies transfer more water vapour to the atmosphere which causes further warming since the water vapour is a GHG
aerosols
Microscopic droplets and particles suspended in the air
what are some positive feedback loops found in the climate system
- increase in the concentration of water vapour in the atmosphere, can cause more warming because water is a radiatively active gas (GHG) = causes more evaporation which further increases in water vapour in the atmosphere
- Soot, or black carbon aerosols, can cause warming by absorbing solar energy = increased warmth of surface
what are some examples of negative feedback loops in climate system
- increase cloudiness caused by more water vapour in atmosphere would result in slowing global warming by reflecting more solar radiation
- soil formation is accelerated by warmer, wetter weather, and soils function as a major sink for organic matter, removing carbon from the atmospheric reservoir
radiative forcing
the amount of change in energy that a given factor causes
positive radiative forcing examples vs negative radiative forcing examples
positive forcing
- carbon dioxide
- halocarbons
- methane
- ozone
- dark surface albedo
negative forcing
- ozone in stratosphere
- light surface albedo
- aerosols
- cloud albedo
negative vs positive forcing
negative - cools the surface
positive - warms the surface
what are 4 key influences on climate
- changes in earth’s rotation and orbit (Milankovitch cycles)
- Variation in solar output which drives temp changes on earth’s surface
- ocean absorption of carbon dioxide (ocean holds 50 times more carbon than the atmosphere - acts as sink)
- Oceanic circulation patterns (ocean water exchanges tremendous amounts of heat with atmosphere- ocean currents move energy from place to place)
insolation
The amount of solar energy that reaches earth’s surface per unit of area in a given period
what three variations alter the way solar radiation is distributed over earth’s surface
- precession (wobbling of earth’s rotational axis - changes location of highest warming from sun)
- obliquity (tilt of earth’s rotational axis)
- eccentricity (change in shape of earth’s orbit around sun)
Milankovitch Cycles
periodic changes in earth’s rotation and orbit around the sun which drive glaciation and interglaciation periods
are radiative forcing of natural changes in solar output less or more than anthropogenic causes
FAR LESS
do oceans hold more or less carbon than the atmosphere
50 times MORE carbon
how does the ocean absorb carbon dioxide from atmosphere
- Direct solubility of gas in water
- Uptake by marine phytoplankton for photosynthesis
- Incorporation into calcareous shells and skeletons by marine organisms
how do warmer waters affect ocean’s ability to absorb CO2
Warmer waters = lower absorption of CO2 as gases are less soluble in warmer water
what are some issues associated with oceans absorbing CO2
leads to acidification of ocean waters
what is the importance of ocean currents
move energy from place to place
ocean currents in equatorial vs near polar regions
equatorial
- Oceans receive more heat from sun and atmosphere than they emit
near polar
- Ocean water emits more heat from sun than it absorbs
Thermohaline circulation
A worldwide current system where warmer, fresher water moves along the surface and colder, saltier water moves deep below the surface (as its denser)
what is the importance of paleoclimate
Gives us a baseline against which to measure the changes that we are see happening in the climatic system on shorter timescale
what are proxy indicators in terms of climate
Type of indirect evidence that serves as proxies (substitutes) for direct measurements
what is the only way we can go further back in time climatically
natural world’s record keeping
(tree rings
carbon dating
sea and ice cores - trapped bubbles in ice core show what the climate was like)
what are some global impacts of climate change
- most northerly regions will experience the greatest warming
- Climate sensitive industries will be affected (fishing, agriculture, forestry…)
IPCC stands for what and the purpose
Intergovernmental panel on climate change
(The most reviewed and accepted synthesis of scientific info about climate change around the world)
do changes in temp have greater impact over land or ocean
over land
- weather records being broken
- extreme weather events are more common
does a warmer atmosphere hold more or less water vapor
more
describe expected changes of precipitation in high and low altitudes
high altitudes
- increase at high latitudes
low altitudes
- decrease at low latitudes
are sea surface temps increase or decreasing
increasing as they absorb more heat which is adding both heat energy and water vapour to atmosphere
will warmer seas cause more storms or stronger storms
stronger storms and NOT more storms
Jet streams
A high altitude air current that blows west to east
what do jet streams influence
much of the day to day weather across NA and Eurasia
what is the most influential jet stream across Canada and USA
polar jet stream
why is the polar jet stream becoming weaker
because of the warming being greatest at the poles
what happens to the polar jet stream as it slows (as it weakens)
the loop becomes longer which can cause a blocking pattern (can block the movement of weather systems and can hold them in place)
glaciers
land-based deposits of perennially frozen ice
what is the risk with warming temps causing mountain glaciers to melt
- risk of sudden floods
- reducing summertime water supplies
how will warming affect permafrost
permafrost plays a key role in slope stability and warming increases chances of landslides
what are some challenges Canada’s arctic is facing
- sea ice is thinning
- sea ice is decreasing in areal extent
- storms are increasing
why is Canada’s arctic warming
Snow and ice cover are melted, darker, less reflective surface are exposed which lowers earth’s albedo and causes more melting
how do sea levels rise
- glaciers and ice melt
- ocean water is warming (liquid expands in volume as temp increases - MAJOR CONTRIBUTOR TO RISING SEA LEVLES)
what are some impacts of rising sea levels
- beach erosion
- costal flooding
- intrusions of salt water in aquifers
how is climate warming affecting organisms
Organisms are adapted to their environments, so any altered environments have the chance to make their adaptions no longer favourable and change how they live
how does climate change affect plants
○ Climate change may increase vegetation which would help mitigate carbon emissions (negative feedback)
○ Climate change might also decrease plant growth which would increase carbon flux to environment (positive feedback)
how does climate change affect species interactions
○ Regions where Precipitation and stream flow increase = erosion and flooding will pollute and alter aquatic ecosystems
○ Region where Precipitation decreases = lakes, ponds, wetlands and streams will diminish which affects aquatic organisms
how does climate change affect agriculture
- Rainfall will shift and droughts in some areas will become more severe = affects agricultural productivity
- Growing season in some areas will shorten which means harvests will be susceptible to drought and crop failure
how will climate change affect forestry
Longer, warmer and direr fire season are affecting trees by
○ Increasing pests and disease outbreaks
○ Invasive species
○ Fires
how is climate change affecting human health
- We will face more heat waves and heat stress
- Respiratory issues from increased air pollution
- Expansion of tropical diseases into temperate regions as vectors move towards the poles
how will climate change affect economics
- Climate change will widen gap between rich and poor
- Concluding that spending money to mitigate climate change now will save great deal of money in the future
what are the two main reasons for 90% of global warming over the half-century
- combustion of fossil fuels
- land use changes (agriculture and deforestation)
Two ways to respond to climate change
mitigation and adaption
mitigation vs adaption strategies for responding to climate change
mitigation
- Aim is to mitigate, or alleviate, the problem
- Choose to pursue actions that reduce GHG emissions to lessen severity of future climate change
- ex. (using clean energy, recovering land fill gases, preventing deforestation)
adaption
- accept that climate change is happening and pursue strategies to minimize its impact on us
- Erecting a sea wall to combat rising sea levels and increase storm surges
- Restricting costal development
- Farming practices to account for drought
what is a grand scale intervention strategy for climate change (example of intervention)
- Geoengineering
(Strategies aiming to increase fluxes in GHG out of the atmosphere
Strategies aiming to reduce incoming solar radiation)
is climate change the fastest moving-area of environmental science
YES
does earth’s climate vary naturally through time? and how are human activities affecting this change?
- yes
- the rapid climatic changes taking place re due to human activities
compare the global warming potential of carbon dioxide, methane, nitrous oxide
- carbon dioxide (smallest warming potential)
- methane
- nitrous oxide (largest warming potential)
as atmospheric CO2 increases, what happens to temperatures
increases
what information to climate models use
- atmospheric circulation
- ocean circulation
- interactions of different spheres
- feedback mechanisms
are there seasonal changes in atmospheric CO2 concentration
yes
- more carbon dioxide ABSORBED during summer (more photosynthesis)
- more carbon dioxide RELEASED during winter (less photosynthesis and more respiration)
what is a trend
a pattern that persists within a data set, even after short-term fluctuations and anomalies have been accounted for
what did the IPCC report conclude
average surface temps on earth have risen since 1906 with most occurring in last decades (not linear increase)
how much has Canada’s ice shelves shrunk over past 100 years
90%
what does IPCC base it climate models on
differing human responses to climate change
what is the intervention response to climate change
set of possible large-scale technological modifications to the global climate system
what is the concern with intervention as a response to climate change
- interfering with global scale earth’s systems
- abandon mitigation efforts
