The Atmosphere Flashcards
origin of UV radiation
nuclear fusion from sun = produces lots of energy (EM radiation). reaction when hydrogen atoms join to produce helium + neutron
2 role of UV radiation
- stimulates vit. D in humans (increases absorption of phosphorus and calcium).
- Plants reflect UV to attract pollinators
in the stratosphere, what happens to UV
UVB (partially) UVC (fully) absorbed by ozone, is converted in chemical energy which is then converted into heat
what happens to UVA
is reflected off of Earths surface
origin of IR radiation
heat absorbed from insolation emitted by Earth’s surface into atmosphere
2 roles of IR
- greenhouse gases absorb IR, converts into heat (greenhouse effect)
- different levels of exposure between surface/deeper water so creates different water temps for different organisms
origin of visible light
insolation from the sun which is reflected from Earth’s surface
2 roles of visible light
- allows for organisms to see
- allows plants to photosynthesise (using it to split H2O)- converted to chem. energy in the products
Anthropogenic sources of CO2 and residence time
- combustion of fossil fuels/wood
- drainage of marshes
+ 100 years
Anthropogenic sources of CH4 and residence time
- paddy fields (rice fields) (anaerobic resp.)
- cattle farming
- landfills (anaerobic resp.)
+ 12 years
Anthropogenic sources of NOx and residence time
combustion of oil/diesel in vehicle engines
+114 years
Anthropogenic sources of tropospheric ozone and residence time
formed when UV reacts with NOx from exhausts/smokestacks
+ 23-28 years
Anthropogenic sources of CFCs and residence time
- aerosols
- fluids for refrigerators
+ 50- several hundred years
definition of residence time
the average time a molecule stays in the atmosphere since leaving it’s source
Match up the relative effects of the gases:
- CO2 = ___
- CH4 = ___
- NOx = ___
- Tropospheric = ___
- CFCs = ___
- 1
- 25
- 160
- 2000
- 25000
what is the role of the Thermohaline circulation in the north atlantic (also known as the North Atlantic Conveyor or the Gulf stream) ?
bring warm water from the Caribbean towards Europe
how does the north atlantic conveyor work?
H2O becomes more dense when cold and so sinks towards the pole. More Saline = more dense
How does the melting of the ice caps affect the north atlantic conveyor?
increases freshwater, so decreases salinity so decreases density, less warm water being deposited. NAC slows/stops
what is El Nino ?
westward wind changes direction. drop in rainfall in Australia. loss of nutrient rich water in south america and also flooding/lots of rainfall.
how does thermal expansion increase sea level rise?
increase temp, increases kinetic energy of H2O molecules. molecules move further apart so occupy more volume
name 3 processes that will increase sea level
- thermal expansion
- melting of sea ice
- melting of land ice
name 3 effects of sea level rise
- salt water incursion
- flooding (increase costs for flood defences)
- erosion
name the potential 5 changes to the cryosphere due to climate change
- reduced snow cover = reduces albedo, faster melting
- glacier movement
- ice shelves = ice breaks off easier, glaciers can move more rapidly
- sea ice/ice sheets = less albedo
- ice lakes = front of glaciers break, water from ice lakes released, causes flooding
what are the 2 things that could happen to reduce the volume of glaciers due to climate change
- increase temp, front of glacier melts, glacier retreats
- increase temp, meltwater lubricates glacier, moves quicker
if u increase the temp, it could either increase or decrease precipitation. Why?
- increase in evaporation
- too hot to condense
changes in frequency/velocity/pattern (wind)
- increase storm damage
- changes areas that receive rainfall
name the 6 ecological impacts of climate change
- changes in migration
- changes to hibernation
- seasonal shifts
- changes in habitat
- changes in long term migration
- island species in danger
2 examples of ecological impacts (organisms)
- adelie penguin = krill pop. decreases, migrates further to find food. Less energy. less successful breeding. + krill live under the retreating ice sheets
- sea turtle = nests being flooded + sea level rise
why is there uncertainty over the use of some data when drawing conclusions for climate models? name at least 4/6
- lack of historical data
- limited reliability of proxy data
- lack of understanding of natural processes/ interconnections
- natural fluctuations could mask anthropogenic actions
- time delay between cause/effect
- human behaviour in the future
name the 4 ways in which we have improved data collection + how they do it
- satellites i.e. cryosat (collect info on ice cover)
- low Earth orbit satellites (info from whole earth surface)
- geostationary orbit (info from a constant position)
- Gravimeter (collect data on ice mass)
+ they use microwaves/ IR
definition of tipping point
key point that leads to new, irreversible developments
definition of negative feedback
environmental change causes a decrease of effect to return to its original value
definition of positive feedback
environmental change that causes other changes which increases original effect
which are positive/negative feedback mechanisms?
- melting permafrost
- increased photosynthesis
- ocean acidification
- rapid decomposition of dead organic matter
- increased low level cloud
- increased cirrus clouds
- increased peat/forest fires
P= positive feedback N= Negative feedback
- P
- N
- P
- P
- N
- P
- P
definition of sustainable
doing something indefinitely and not harming environment
definition of geoengineering
tech that will help to control natural processes to reduce anthropogenic greenhouse effect
name 4 examples of geoengineering
- spraying sea salt into clouds (increases albedo)
- afforestation
- ocean fertilisation (ocean greening) - carbon absorbing algae
- pumping aerosols into atmosphere (increase reflectivity)
what was the kyoto protocol
international agreement to reduce CO2 emissions/greenhouse gases. Each country puts a cap/limit on emissions from large companies
what was the Paris Agreement
international agreement to reduce carbon emissions. To limit global warming well below 2 degrees but make efforts to stay below 1.5 degrees above pre-industrial levels. meet every 5 years. No penalties are given to those who do not meet their goal.
when doing a research project (like the rowland-molina hypothesis) what 7 steps should u take/consider?
- look at other research
- hypothesis
- lab investigations
- modelling
- collection of evidence in the actual place u should be testing i.e. in atmosphere
- alterations to the model (if needed)
- further collection of evidence
what 3 things did the Rowland-Molina hypothesis say?
- persistence of CFCs = CFCs chem. stable so can be carried up to stratosphere
- dissociation by UV + release of chlorine molecule (Cl)
- prevents reaction between O + O2 to form O3
what are the 3 symbol equations to show the effects of CFCs
- Cl + O3 = ClO + O2
- ClO + O = ClO2
- ClO2 = Cl + O2
Rank the types of UV from least dangerous to most:
UVB, UVA, UVC
UVA, UVB, UVC
what does UVB cause?
mutations (cancer), cataracts, damages crops
what does UVC cause?
kills bacteria/ viruses
what are the 3 ways data is collected on the depletion of O3
- ground based data collection (increased levels of UV detected on ground)
- aerial/satellite surveys (increased UV light reflected from earth)
- Variability results: concentrations of O3 varies at altitude (severe: 12-24 km), times of year (sept-dec) and place (Antarctica)
why is O3 depletion greatest in Antarctica? (4 reasons)
- stratospheric ice particles not present in warmer latitudes
- composed of ice crystals = surface for reactions that increase O3 breakdown
- winds create polar vortex (high Cl concentrations)
- in spring = light splits Cl producing free radicals
What was the Montreal protocol
stop producing CFCs
how did the montreal protocol decrease CFCs? (3 ways)
- use of alternative processes = stick deodorants/ pump action sprays instead of aerosol cans
- alternative materials HFCs and HCFCs refrigerants introduced (less chem. stable). HFAs used in Asthma inhalers
- disposal techniques of CFCs = (draining and incineration)
