Atmosphere Flashcards
What are examples of ocean currents affected by climate change?
The North Atlantic Conveyor
El Nino and La Nina
Where is the ozone?
Stratosphere 12-24km
What is the concentration of ozone?
13 parts per million
What are some geoengineering techniques to reduce climate change?
Painting roofs white, add nutrient to oceans for plankton blooms and put solar shades in orbit
At what point is there considered an ozone ‘hole’?
Less than 220DU, the norm is 300DU
In what form is oxygen present in the atmosphere?
Monoatomic, diatomic and triatomic
What is meant by the term ‘dynamic equilibrium’ in the atmosphere?
Natural processes being in a state of balance which maintains the average composition of the atmosphere
What is the wavelength of IR?
700nm-1mm
What is the wavelength of UV?
100-400nm
What is the wavelength of visible light?
380-700nm
What does anthropogenic mean?
Environmental change caused or influenced by humans, either directly or indirectly
What are the dangers of chlorofluorocarbons?
They deplete ozone layer, allowing more damaging UV radiation to enter
What is an ice field?
Ice covering an area less than 50,000km2, topography of ice follows underlying land
What is the formula for methane hydrate?
CH4 5.75H2O
What is permafrost?
Frozen waterlogged soil with dead organic matter that decomposed slowly under anaerobic conditions, to produce methane
What are the control methods for CO2?
Reduction in fossil fuels, low-emission energy sources and carbon sequestration
What are the control methods for NOx?
Catalytic converters, public transport and adding urea to power station effluents to reduce NOx concentration
What is the control method for tropospheric ozone?
Controlling NOx emissions
How much harmful UV does ozone block?
90-99%
Why are HCFCs better than CFCs?
They are less stable so react in the troposphere, not the stratosphere, where they can harm ozone
What are HFAs?
Hydrofluoroalkanes
What is the risk of hydrocarbons in aerosol propellants?
Flammable
What are examples of EM radiation being converted into chemical energy?
Homolytic fission of O2 to form ozone
Photolysis of water for photosynthesis
What are ice sheets?
Ice covering an area over 50,000km2, only two exist Greenland and Antarctica
What is a glacier?
Large body of dense ice moving over land under its own weight
What is sea ice?
Relatively thin ice that forms on the sea as water freezes, forms from the sea water but crystallises as freshwater
What is the heat-island effect?
Urbanized areas that experience higher temperatures due to low albedo of surfaces
What’s an argo float cycle?
10 days submerged, resurface, transmit data and then submerge again
What do argo floats collect data on?
Temp and salinity
What is the Gaia hypothesis?
Organisms have helped maintain stability in many environmental features, they have evolved over geological timescales to alter natural processes
What are the control methods for CH4?
Reduce landfill and collection of gas over landfill, reduce livestock and improved recovery of gas
What are the control methods for CFCs?
Alternative materials: butane or propane in aerosol and HCF or HCFC in fridges
Alternative processes: triggers and pumps not aerosol and roll-on deodorant
What is an ice shelf?
A floating mass of ice attached to ice on land, they are formed when glacial ice flows off the land onto the sea
What are some positive feedback mechanisms?
Increasing water vapour
Melting snow and ice
Increase peat and forest fires
Melting permafrost
Ocean acidification
Release of methane hydrate
Soil decomposition
What is the wavelength and characteristics of UVB?
280-320nm, almost fully absorbed by ozone
What two reactions occur with chlorine in the stratosphere?
Cl + O3 = ClO + O2
Cl + O = ClO
Both decrease ozone
What are examples of climatic processes changing as a result of climate change?
Wind pattern changes and changes in precipitation
More Rossby waves for more intense weather
What causes rising sea level?
Thermal expansion of water (very slow) and melting of land ice
What are Rossby waves?
Waves created by the meandering path of jet streams, they may be atmospheric or oceanic
What affects ocean currents?
Winds, evaporation, heating and cooling (density) and salinity
What are the impacts of climate change on human society?
Health, water and food supplies and impacts on infrastructure
What are the harmful effects of UVB?
Converted to chemical energy as it breaks up biological molecules causing skin damage, DNA mutations, skin cancer, cataracts, leaf tissue damage and damage to marine organisms
How is tropospheric ozone formed?
Heterolytic fission of NO2 to NO + O, which leads to O + O2 = O3
At what point does thickness in ozone vary?
Seasonally and geographically
What is ocean iron fertilisation?
Adding iron to oceans to stimulate plankton blooms to increase carbon sequestration as they produce calcium carbonate shells which sink to the seabed and store carbon when they die
What is the wavelength and characteristics of UVA?
320-400nm, not absorbed by ozone or O2
What are the advantages to HFCs?
No chlorine, so it doesn’t cause ozone depletion
What are the disadvantages to HFCs?
More expensive, don’t work as well and greenhouse gas
What are ecological changes caused by climate change?
Changes to phenology, habitat, precipitation, hibernation patterns and species distribution
Why don’t winds blow in straight lines?
Earth’s rotation creates a coriolis force that sends it into a spiral fashion (Rossby wave)
What are ice caps?
Ice covering an area less than 50,000km2, thick enough to have its own topography
What is the wavelength and characteristics of UVC?
<280nm, completely absorbed by ozone and O2
What is the chlorine cycle in the stratosphere?
Cl + O3 = ClO + O2
ClO + O = ClO2
ClO2 = Cl + O2
What’s the importance of the atmosphere to life?
Gas for natural processes
Absorbs EM from sun
Delays escape of IR
Creates wind to spread heat
Creates ocean current
Pressure for liquid water
Gas for human exploitation
What changes in the cryosphere occur from climate change?
Reduction in snow cover
Changes in land ice- retreating and extending glacier
Loss of ice shelves- positive feedback mechanism
Changes in ice thickness and area- albedo
Ice lakes- Himalayas flooding
Ice and snow fed rivers- meltwater
What are some impacts of GCC on infrastructure?
Road heat stress, track buckling, drainage, landslide and bridge damage
How does methane hydrate form?
Dead organic matter in deep sea sediments has decomposed to form methane, under high pressure and low temp it forms methane hydrate
How is NOx released anthropogenically?
Fertiliser use and N2O by denitrifying bacteria
How are CFCs released anthropogenically?
Aerosol propellants, fire extinguishers, refrigerants, solvents and expanded foam plastics
How much incoming light is UV?
10%
1/3 penetrates
Where are all the gases in the atmosphere?
80% troposphere
99.9% stratosphere
What causes tropospheric ozone?
Photochemical breakdown of NOx
How is methane released anthropogenically?
Ventilation of coal mines, leaks from natural gas field and pipelines
How much has O3 concentration decreased in Antarctica and Arctic?
Antarctica: 2/3
Arctic: 1/3
What effect does climate change have on herbivores such as butterfly and moth caterpillars?
Could provide more food, but many plants produce toxins as chemical defence and if plant growth begins earlier in the year then the toxins may build up and kill the organisms
How does climate change impact wetlands?
May enlarge or shrink with precipitation changes
How does climate change effect certain trees?
Oak trees have deeper roots and will be bale to survive droughts whereas beech trees have shallower roots
How does climate change effect dormouse?
Hibernation may be disturbed during the warmer winter, causing them to use up stored fat, they may starve before spring
How are bats UK effected by climate change?
Warmer, shorter winters may increase their chance of survival during hibernation and warmer weather may increase the population of food species such as night-flying insects. Wetter stormier weather may reduce the time for which bats can feed, which may reduce survival
What are the relative strengths of greenhouse gases?
CO2- x1
CH4- x25
NOx- x160
Tropo ozone- x2000
CFCs- x25,000
How can greenhouse gases be reduced?
CCS, carbon sequestration and geoengineering
How can UV light damage organisms?
Skin cancer, cataracts, sun burn, DNA damage, leaf tissue damage, reduced photosynthesis and damage to marine organisms
What has been a successful treaty to reduce CFC emmission?
The Montreal protocol
What are three example of negative feedback?
Increased low-level cloud cover, increased CO2 more photosynthesis and ice sheets melting means more water in the ocean so more CO2 dissolves
