the atmosphere part 2 (global climate change) Flashcards
what is a large proportion of solar radiation in the form of
visible light
state 6 major anthropogenic sources if greenhouse gases
transportation / electricity and heat / industry / land use change / agriculture
list the 5 main greenhouse gases produced by anthropogenic sources
carbon dioxide / methane / nitrous oxide / tropospheric ozone / chlorofluorocarbons
name 2 human activities that majorly produce CO2
combustion of fossil fuels (natural gas, coal, crude oil) / deforestation
how does deforestation affect global climate change
co2 levels rise due to reduced rate fo photosynthesis / combustion of vegetation (eg.slash and burn) / aerobic respiration of remaining dead plant material
name a 2 human activity that majorly produces methane
anaerobic archaea / formation of fossil fuels (ventilation of coal mines, leaks from natural gas fields)
how does anaerobic archaea affect global climate change
paddy fields and landfill sites and intestines of livestock, they produce methane from decomposition of organic matter
name 2 oxides of nitrogen that act as greenhouse gases and how they’re formed
nitric oxide (NO) nitrogen dioxide (NO2) formed when nitrogen and oxygen react in the air at high temps /, nitrous oxide (N2O) formed by bacterial dentrification of nitrate fertiliser
how does NO and NO2 affect global climate change
INDIRCET greenhouse gases. released from exhausts- partake in a series of reactions that form tropospheric ozone- greenhouse gas NO rapidly converts to NO2 so reaction takes place very frequently
how is tropospheric ozone produced
NO2 –> NO + O, O2 + O –> O3
what were CFCs used in
aerosol, refrigerants, solvents and production of polystyrene
how is GWP calculated
compares amount of heat trapped by a certain mass of the gas, calculated over a specific time interval
what does a high GWP correlate to
a large infrared absorption and a long atmospheric residence time
why is carbon dioxide of most concern
since it is released in largest amounts by human activity, not because its the most powerful
name 2 changes in the oceans caused by climate change
sea level rise / ocean current changes
what effects sea level rise
thermal expansion and melting land ice
why does thermal expansion increase sea level
as the atmosphere causes the sea to heat up, it expands
why will thermal expansion take a long time to cause a dramatic increase in sea level rise
there is an enormous amount of water in the ocean / water has a high specific heat capacity, will take a long time for the temp of the sea to ‘catch up’, deep water will only warm up when slow moving currents bring it to the surface
when water is warmed up do water molecules expand or does the water expand as whole
water expands as a whole
why does ice floating on the sea not cause a rise in sea level
because it contracts during melting and occupies the same volume of water as the water displaced when it was ice
what ice causes sea level to rise
land ice because the water flows into the sea and increases the volume as they displace seawater
describe the water in near south America and why its like that
winds blow westward across pacific ocean causing cold water drawn up near south America, rich in nutrients causing massive algal blooms, feed a rich food web.
why is the there a massive algal bloom in the cold water in south America
because cold water in contains more nutrients
how does a rich food web from the cold south American water impact humans
feeds important fisheries
explain the movement of water as the current continues westward from south America
the water warms up as it travels along the east coast of Australia as a warm current
how does the cold current affect rainfall patterns
cold costal current cools down any rain-bearing winds heading over the sea towards the land, causing water vapour to cool and condense as rain before it reaches land
how does the warm costal current affect rainfall patterns
winds blowing towards land are likely to retain water vapour and may cause rain to fall on the land
what causes the ocean current to reverse
wind
what affect does the ocean current reversing have
prevents nutrient upwelling in south America- rich food web collapses / rainfall in Australia drops while desert in South America experiences heavy rain and flooding
describe the water pattern in el nino
warm ocean water develops in South America
how does the current slow down from melting land ice in Greenland
melting land ice dilutes salty surface water, makes it less dense, more difficult for cold water to sink so the current slows down
why does this current make north west Europe water warmer
the current transfers heat from the tropics to north-west Europe
what would happen to north-west Europe water if the current from the tropics slowed down
it would become much cooler
how do you monitor ocean currents
with cataloguers on argo floats
what 5 aspects of the cryosphere is affected by rising global temperature change
reduced snow cover / glaciers / land ice caps and ice sheets / ice shelves / sea ice
how is snow cover affected by rising global temperature change
amount and duration. less snow falls and fallen snow melts quicker- can affect rivers: run off from melted snow from mountain means river level fluctuates and river doesn’t dry up. no snow in summer so no runoff so river dries up in dry seasons
how are glaciers affected by rising global temperature change
changes in extent and speed of movement. increase rate glaciers melt. meet water flows to the bottom and lubricates it movement towards the sea, ice burgs break off and melt into the ocean / glacial lake outburst floods
how are land ice caps and ice sheets affected by rising global temperature change
changes in thickness and movement. increases melting of ice caps as well as lubricating their movement.
why is it unlikely to lose an ice sheet
so huge it would take thousands of years for them to melt completely, warmer temps are linked to more precipitation, replaces the melted ice water
how are ice shelves affected by rising global temperate change
speed up the break up of ice shelves and the impact on land ice movements. due to their immense weight, they act as plugs to reduce rate of glacial flow off the land, when ice shelf breaks up it releases the glacial flow, increasing sea volume
why do ice shelves melting not affect the volume of the sea
they’re already displacing their own weight of underlying water
how is sea ice affected by rising global temperature change
changes in thickness and area of sea ice cover. sea ice grows in winter and shrinks in summer, however overall it is being reduced. when it melts the darker ocean below has a lower albedo so heats area surrounding
why does sea ice not affect the volume of sea
its already displacing its own weight of underlying water
what are most climate systems driven by, and what might change the processes involved in these systems
energy from the sun, retention of more energy from the sun in the atmosphere may change the climate systems
how may wind patterns change due to climate systems
velocity, frequency and density. stronger winds = more storm damage. direction change = rain distributed by wind may fall in different areas
how may precipitation change due to climate systems
higher temp increases = increased evaporation rates = increased precipitation / if too warm for water to condense, areas that get lots of rain may get less / cold areas = little rain bc it condenses and falls before it reaches land- if warmer = more precipitation as water vapour is carried further before condensing
Name 4 uncertainties of ecological impacts of climate change
Changes in species survival caused by changes in abiotic/ biotic factors / changes in species distribution / population fragmentation
How can temperature change affect plants
Cause them to grow faster - provide more food for herbivores eg caterpillars, moths - plants may produce toxins that build up in their leaves to protect them from being eaten so if plant growth begins earlier, toxins build up sooner which could kill caterpillars
How may uncertainty of if ecological events change due to climate change
Flowering, migration, nesting — survival of interdependent species may be reduced eg, pollinating insects aren’t present when flowers are produced which affects bee lifestyle, flowers and bees are out of sync
What happens to bat populations if climate change increases
Produce more nights that are warm enough to feed and fewer when they’re inactive and must fast / increase insect survival and therefore food supplies for bats
How can bat populations be effected by warmer climate change
Increase evaporation and rainy periods and stormy periods when bats can’t fly
Why may some species not be able to recolonise if conditions change
May colonise new areas more slowly than they disappear from their old range / suitable new areas may not be available / human land may block movement / species live in interdependent communities of species, not all will move at the same speed
Why is there uncertainty over the use of some data in drawing conclusions within monitoring climate change
Lack of historical data / limited reliability of proxy data / lack of understanding of natural processes that control weather (ocean currents and their interconnections) / natural changes and fluctuations that mask changes caused by anthropogenic actions / time delay between cause and effect
State 2 examples of negative feedback
Increased temperature - increased photosynthesis rates - plants store more carbon in biomass - levels of co2 in atmosphere lowered - reduced temperature / increased temp - increased evaporation of water - formation of more low-level clouds - albedo increases - more sunlight reflected so less solar heating - reduced temperature
State 2 examples of positive feedback
Increased temperature - faster melting of permafrost in polar regions - more methane released - temp increases even more / increased temp - increased warming of the seas - more melting of methane hydrate in marine sediments - methane released and travels to atmosphere - temp increases / increased temp - increased rate of aerobic decomposition of dead organic matter in soil by bacteria - more co2 released to atmosphere - increased temp
What is the debate about clouds and positive and negative feedback to do with
Low-level clouds contribute to negative feedback, high altitude cirrus clouds contribute to positive feedback - more evaporation leads to both types
Give 2 ways to reduce co2
Carbon sequestration / carbon capture storage (CCS)
Give 3 ways to reduce methane
Reduced dumping of waste in landfill sites / reduced livestock production / better collection of gas from coal mines and oil facilities - can be converted to co2 which is a weaker GHG
Give 3 ways to reduce oxides of nitrogen
Reduce of internal combustion engines / catalytic converters in vehicle exhausts / addition of urea to power station effluent if diesel exhaust / n2o controlled by making fertiliser application more efficient and injecting liquid organic fertiliser deeper into the soil
Give 2 methods of how to reduce CFCs
Use alternative materials (eg butane or propane in aerosol or hydroflurocarbons in refrigerators) / use of alternative processes (stick deodorant instead of aerosol)
What are the three types of uv
UV(a) UV(b) and UV(c)
Why is UV(a) and UV(c) not of a concern
A isn’t significantly absorbed by ozone and C is fully absorbed and never reaches earths surface
Why is uv(B) of concern
It’s not absorbed in the atmosphere so it reaches the earths surface and is absorbed by living cells, the energy is absorbed and turned into chemical energy as it breaks up biological molecules causing damage and mutation to the dna in exposed cells and damage to plant tissue and marine plankton
Why are CFCs good for many uses
They’re very chemically stable and can be liquified with pressure, are good solvents of grease and oil and aren’t flammable or toxic
Why are CFCs highly persistent
They have very high chemical stability so take many years to break down
Why do CFCs stay in the atmosphere for so long
They’re very persistent and have low solubility so aren’t washed out of the atmosphere by precipitation
What part of CFCs cause ozone depletion
Chlorine atoms which are released in the stratosphere from being broken down by UV light
how is carbon capture and storage performed
capture of co2 or removal of carbon from fuel / transport by road tanker, ship or pipeline / co2 storage underground in depleted oilfields, gas fields, aquifers or use in secondary oil recovery
give 3 ways to reduce oxides of nitrogen
reduction of internal combustion engines / catalytic converters / addition of urea to power stations or diesel engine exhausts
give 2 ways to reduce CFCs
use alternate materials (eg propane and butane in aerosols) / use alternative products (stick deodorant over aerosol)
name the 3 types of UV
UV(A) UV(B) UV(C)
Why is uv a and c not of concern
uv(a) isn’t significantly absorbed by the ozone and uv(c) is fully absorbed by the ozone so doesn’t reach earth
why is uv(b) of a concern
its not fully absorbed in atmosphere so will reach the earths surface and can be absorbed by living cells, which is converted to chemical energy and breaks up biological molecules and causes damage/mutation to DNA in exposed cells
Give the equations to make ozone
O2 + UV -> O + O
O + O2 -> O3
State the reactions to explain ozone depletion
CF3 + UV light -> CFCL2 + CL
CL + O3 -> CLO + O2
CLO+ O -> ClO2
ClO2 + Cl -> O2
where do chemical reactions involving chlorine and ozone require UV(B) occur most easily
at very low temperatures when ice crystals form in polar stratospheric clouds that provide catalytic surfaces that speed up reactions
when, in antartica does ozone depleting reactions take place
spring, when ice crystals are still present in clouds and there is UV
what is the Antarctic polar vortex
when high altitude winds enters the stratosphere and circulates around the continent from autumn through spring
how does the antarctic polar vortex affect ozone
makes it hard for ozone to come in from the outside to replace whats been destroyed
why is the arctic ozone not as bad as the antarctic ozone
arctic polar vortex is weaker, giving more of an ozone dent than hole
name 3 methods of ways to collect data on ozone depletion
ground-base data collection / aerial surveys / satellite surveys
what is the method for ground-base data collection
principle that less UV(b) reaching the ground, the more stratospheric ozone above - dobson spectrophotometer
what is the method for aerial surveys
either by aircraft or helium balloons. Aircraft contains an instrument for measuring chlorine monoxide concentrations in the upper atmosphere. helium balloon carries an ozone monitor
what is the method for satellite surveys
used for remote sensing of total atmospheric ozone levels, if there is more ozone in the atmosphere more UV will be absorbed and less will be reflected by earth and its atmosphere, satellite detects amount of reflected UV
what will effect the readings of the dobson spectrophotometer
clouds and polluntants
what is an issue with the helium balloon aerial survey
it can drift on winds, so sampling points and unpredictable, sampling instruments must also be able to survive the parachute journey back
what is an advantage and disadvantage to using aircrafts over helium balloons for methods of ozone monitoring
aircrafts fly higher and follow a predictable route / they’re more expensive
what is the advantage and disadvantage of using satellites for ozone monitoring
they have the highest financial start up cost / collect most data, so low cost per data unit. sample from all areas of the planet predictably, rapidly with high frequency
in what 3 ways can the concentration of the ozone in the stratosphere vary
spatially (vary depending on where on earth the atmosphere sits) temporally (antarctics hole forms from sep-nov) with altitude (form where high conc of oxygen particles and uv intensity are both found)
what was the Montreal protocol (1987)
an international agreement which phased out all manufactured use of CFCs and other ozone depleting substances
what else did the Montreal protocol encourage
use of alternative processes, use of alternative materials, collection and disposal of CFCs and other ODSs
state some alternative processes from promoted Montreal protocol
trigger and pump action spray cleaners over aerosols / stick deodorant over aerosol
state some alternative materials from promoted Montreal protocol
butane or propane in aerosols / hydrofluorocarbons in refrigerators
how do you dispose of CFCs
they must be released from their appliance and then immediately captured and destroyed by incineration
why was the montreal protocol more successful than the kyoto protocol
ozone depletion has a simpler cause and fewer feedback mechanisms than climate change / Montreal has greater political agreement, where major countries have signed up / more evidence to support ozone depletion by ODSs than anthropogenic climate change / clear alternatives to CFCs, fossil fuels are more difficult to replace
