Fichas
Atmosphere Flash Cards
Fichas del conjunto (145)
- 1When was earth formed?4.6 billion years ago
- 2How was earth formedCondensation and Accretion of gases and other material
- 3How hot was early earth?100 degrees Celsius
- 4What was the first atmosphere composed of?Hydrogen and Helium
- 5Which factors affect a planets atmospheric composition?Distance from sun
Size of planet
Presence of rocks and water
Gases present - 6What set the composition of earth's second atmosphereMeteorite/extra terrestrial impact
Volcanic emissions
Rock weathering
Balance with oceans
Chemical reactions - 7When did life first appear?3.5 billion years ago
- 8What were early life forms?Extremophiles (Archea)
- 9How did extremophiles generate energy?Lithotrophy - pulled energy from inorganic molecules inside the cell
- 10How do cyanobacteria exist today?Stromatolites
- 11How was oxygen initially createdCyanobacteria produce O2 and Organics
O2 reacts with lose oxygen
O3 is formed - 12When did plants first appear?2.1 billion years ago
- 13What did the appearance of plants coincide with?A rapid rise in oxygen in the atmosphere
- 14What is the composition of today's atmosphere?Nitrogen 78%
Oxygen 21%
Argon 1% - 15What is the mass of the atmosphere?5.15 x 10 ^15
- 16What are the layers of the atmosphere? List them from ground level upwards.Troposphere
Stratosphere
Mesosphere
Ionosphere
Thermosphere
Exosphere - 17What is the function of each atmospheric layer?Troposphere - Weather
Stratosphere - UV Protection
Mesosphere - Meteorite protection
Ionosphere - Northern lights
Thermosphere - Absorb and reflect heat
Exosphere - Satellite orbit and transition to space - 18What is the Chapman mechanism?A series of equations describing ozone reactions in clean air
- 19What determines the peak level of ozone productionThe availability of light
The availability of gas molecules - 20How does aurora borealis form?Electrons colliding with gas molecules
- 21What is the environmental lapse rate for: - temperate environment - dry environmentsTemperate -6.5/km
Dry -10/km - 22What's the definition of air pressure?The mass of the air column above
- 23What is air pressure at ground level1
- 24How do we measure air pressure?Pascals
(CHAMELEONS!) - 25What causes atmospheric circulation?Heat imbalance
- 26Where is: Heat surplus Heat defIcitHeat surplus - Equator
Heat deficit - Poles - 27What is the tricellular model?A model of the 3 main convection cells responsible for circulating heat around the globe
- 28What are the 3 cell main convection cells and their extent?Hadley cell : 0/Equator - 30
Ferrel cell : 30-60
Polar cell : 60 - 90/pole - 29What is the ITCZ?Inter tropical convergence zone
A thick band of storms that fluctuates around the equator - 30What is the jet stream?Current of fast moving air
In the northern hemisphere
Over area of strongest surface temp - 31Describe the 4 main climatesPolar
Temperate
Desert
Tropical - 32What can be a physical barrier to atmospheric movement?Mountain ranges
Vegetation
Cities - 33What is the average UK windspeed?5m/s
- 34How long can it take pollutants to cross continents?A few days
- 35What physical evidence do we have of long distance atmospheric transport?Volcanic ash and Sahara dust
- 36Which pollution event was April 1986?Chernobyl disaster
- 37Which three factors influenced distribution of radioactive particles from the Chernobyl event?- Wind regimes
- Rainfall
-Equator barrier to Southern Hemisphere - 38Which pollution event was May 1980?Mount St Helens volcanic eruption
- 39What caused such rapid transport of the Mt St Helens eruption debris?Material was ejected 18km upwards during eruption and straight into stratosphere
- 40What is a chemical lifetime?The amount of time a chemical can exist in the atmosphere before being physically or chemically removed
- 41What is cross equatorial flow and how long does it take?The amount of time taken to cross the equator
1 year - 42How long does it take to cross the tropopause?Three years
- 43Which 2 processes enable pollutants to cross the tropopause?Convective upshot
Tropopause folding - 44Name the 5 oceansAtlantic
Pacific
Indian
Southern
Arctic - 45Which hemisphere do we find the: Arctic? Antarctic?Arctic - Northern
Antarctic - Southern - 46What is the overall trend in Antarctic sea ice?Rapid ice loss in some areas and rapid ice gain in others but overall stability
- 47What is the seasonal area change in Antarctic sea ice?3 to 18 million km2
- 48What is the overall trend in Arctic sea ice?Steady decline since 1979
- 49What is the seasonal area change in Arctic sea ice?6 to 15 million km2
- 50What is an ocean gyre?A closed loop of ocean circulation
- 51What are the 5 major ocean gyres?North Atlantic
South Atlantic
North Pacific
South Pacific
Indian Ocean - 52What are the 2 subpolar gyres?- Alaska
-Greenland - 53How do we describe eastern boundary currents?Wide
Shallow
Slow - 54How do we describe western boundary currents?Narrow
Deep
Fast - 55What controls boundary currents?Coriolis
Wind direction - 56What direction are equatorial ocean currents in the northern and southern hemisphere?East to West in Both hemisphere
- 57Why is the antarctic circumpolar current, the only current able to totally circulate the globe?Has no land masses in the way
- 58What are the parameters of the antarctic circumpolar current?2000 km wide
4000 km deep - 59What is unique about the Indian Ocean circulation?It can reverse seasonally
- 60Why is the global ocean conveyor belt important?- Transports heat
- Spreads nutrient
- Connect surface and deep sea - 61What forms the (NADW) North Atlantic deep water?- Cooling of Atlantic waters
- Brine rejection due to ice formation - 62Why does brine rejection occur?When salt water freezes, the salt cannot fit into the ice structure and so it is expelled during freezing
- 63What is the importance of the (AMOC) Atlantic meridional current?Moderating climate in Europe
- 64What natural tracers can oceanographers use to track ocean circulation- Chemical composition
- Temperature
- Salinity
- Dissolved oxygen - 65What’s anthropogenic tracers can be used to track ocean circulation?- CFC Ratios
- 14C spike (from atomic bombs) - 66What are the three distinct vertical layers of the ocean?- Photic zone
- Bathyal zone
- Abyssal zone - 67What is pycnocline?A layer in which density rapidly increases with depth
- 68What is a halocline?A layer in which salinity rapidly increases with depth
- 69Are pycnoclines permanent or temporary?Both
- 70What causes ocean mixing?Heat convection
Surface winds
Tides
Biological disturbances (I.e. Whales diving) - 71What is an ocean mass?A defined parcel of ocean water with its own unique temperature and salinity
- 72What are the boundaries between water masses called?Fronts
- 73Identify two methods used to monitor oceans- Expendable bathythermography (XBT), measure temperature as sinking
- ARGO Floats, rise to surface very 10 days and record temperature and salinity on way up - 74What is the density of freshwater?1000 kg m^3
- 75What is the density of saltwater?1021 - 1070 kg m^3
- 76Why is the density of seawater higher?Salt content increases the density
- 77What causes variation in seawater density?- Glacial melt
- Rivine input
- Evaporation - 78How does temperature influence water density?It controls how packed the molecules are
- 79What temperature does maximum density occur at?4 degrees celsius
- 80How does salinity affect density?More saline, more dense
- 81Which is more saline, the Atlantic or the Pacific?Atlantic
- 82How does pressure influence density?Pressure pushes molecules closer together and so increases density
- 83What does water density influence?Vertical movement of water
Water mixing
Stratification strength - 84What is the significance of convection and subduction in the oceans?It ventilates the deep and shallow ocean
- 85What is static stability?A measurement of the tendency of a water column to overturn
- 86What symbol do we nominate to water static stability?E
- 87What does it tell us if E < 0 E = 0 E > 0E<0 - Unstable
E = 0 - Neutral
E>0 - Stable - 88When do we get mixing?When two water parcels of differing properties meet
- 89Why can greater property differences make mixing more challengingA stronger difference has strong restrictive force so there is less time to mix before equilibrium is reached.
- 90How can turbulence encourage mixing?Increases the frequency of the movement of water
- 91What kind of diffusivity was found to be essential for completing the ocean conveyor belt?Diapycnal eddy diffusivities
- 92Where is Diapycnal eddy diffusivity typically associated with?Rough bottom topography
- 93When does salt fingering occur?Mixing process that occurs when relatively warm, salty water overlies relatively colder, fresher water. It is driven by the fact that heated water diffuses more readily than salty water
- 94What are the major ions in seawater?- Chloride
- Sodium
- Sulphate
- Magnesium
- Calcium - 95Is the ratio of ions in seawater, variable or constant?Constant
- 96Why are the major ions always consistent in seawater?The processes that remove/supply these ions are much slower than the rate of ocean circulation
- 97What is the average salinity of sea water?35 psu
- 98What are and where are the extremes of ocean salinity?LOW - Baltic - 10 psu
HIGH - Mediterranean- 38 psu - 99Why is the Atlantic more saline than the Pacific?1. Rockies/Andes block the atmospheric freshwater transport
2. Trade winds are dry from passing over desert so promote greater evaporation - 100Identify 6 factors that control seawater salinity1. Precipitation (Rain/Snow)
2. River run off
3. Melting of ice
4. Groundwater flow to ocean
5. Freezing of seawater
6. Evaporation of seawater - 101What are the main factors controlling addition/removal of freshwater?Evaporation and Condensation
- 102When Evaporation > Condensation, do we see higher or lower salinity?Higher salinity
- 103When Evaporation < Condensation, do we see higher or lower salinity?Lower salinity
- 104How will global warming influence the hydrological cycle?Will be intensified, contrasts will become more extreme
- 105What is the principle that backs the intensification of the water cycle with global warmingWith every 1 degree rise, 7% more water vapour can be held
- 106Where are low salinities frequently observed?River mouths
- 107How does ice formation and melt affect salinity?Formation - increases salinity, as salt is expelled during freezing
Melting - decreases salinity, as adds fresh water back - 108What is the research on the AMOC currently focused on?Whether the freshening from glacial melt in the sub polar Atlantic is wreaking the AMOC
- 109How does the freshening of water impact the AMOC?- Alter surface stratification
- Reduce deep water convection
- Reduce amount of heat moving northwards - 110Ultimately, what does a weakening of the AMOC mean for Europe?A climate more similar to that of North America (very cold and very wet!)
- 111Has the AMOC experienced weakening before?8,200 years
Collapse of Laurentide ice sheet melt dam at Hudson Bay. - 112What are the proposed causes of AMOC weakening?1. Meltwater from Greenland glaciers
2. Intensifying sub polar gyre
3. Increased freshwater from the arctic - 113Why is ocean temperature and heat content of interest?1. Energy budget
2. Poleward heat transport
3. Seasonal climate moderation
4. Impact on ocean biology, chemistry and physics - 114What’s the range of sea surface temperatures?-1.8 degrees to 30 degrees
- 115What is the general sea surface temperature pattern?Decreasing towards poles
- 116How does temperature change with depth and why?Temperature decreases with depth.
1. Source of heat at surface
2. Cool water sinks - 117What is the difference between temperature and heat content?Temperature is the amount of energy of in PARTICLES in a substance
Heat content is the amount of energy in a SYSTEM - 118How does heat capacity relate to water?Water has a high heat capacity and can absorb large amounts of heat
- 119How does the ocean take in heat?Heat is received by the deans through exchanges with the atmosphere and the sea surface
- 120What are the Radiative fluxes that influence ocean heat?- Albedo
- Atmospheric composition
- Solar elevation
- Seawater turbidity - 121What are the Turbulent fluxes that influence ocean heat?- Temperature
- Humidity
- Wind speed - 122How long has the earth been in radiative imbalance and what does this mean?Since 1970, earth takes in more energy than it expels
- 123How much of the excess energy has the ocean absorbed?93%
- 124Which is the ocean so effective for heat absorption?- Large mass
- Low albedo
- High heat capacity - 125At what rate has ocean temperature risen?0.11 degrees per decade
- 126In which hemisphere is warming most extreme?The Northern Hemisphere
- 127When was there an ocean warming hiatus?1998
- 128What is it believed the ocean warming hiatus could be caused by?- Redistribution of heat in oceans
- Cyclical changes in solar activity and La Niña
- Volcanic eruptions reducing solar activity - 129What causes regional variation in ocean warming?- Surface heat fluxes
- Altered ocean circulation - 130Give two examples of anomalous events in sea surface temperature1. Pacific warm blob (2013-2014)
2. Atlantic cold blob (2015-2016) - 131How does albedo differ over - Sea ice - Open oceanSea ice - 80% reflection
Ocean - 10% reflection - 132What are the major impacts of rising ocean temperatures?1. Ice melt
2. Sea level change
3. Alter ocean circulation
4. Impacts on ocean processes - 133How will ocean warming impact dissolved oxygen?1. Increased stratification, limits oxygen to depth
2. Reduced gas solubility
3. Increased oxygen demand at higher temperatures - 134What % decrease will we see in oxygen solubility?3-6% Decrease in oxygen
- 135By what % are oxygen minimum zone expecting to increase?%10
- 136At what depth does wind affect ocean circulation?Down to 150m
- 137What angle does the current move in relation to the water?45 degrees
- 138What direction is the deflection in each hemisphere?Northern hemisphere - to the right
Southern hemisphere - to the left - 139What causes deflection of the oceans?The coriolis force?
- 140What can Ocean deflection cause?Convergence and Divergence
- 141Why does Coriolis affect the oceans?Water isn’t fixed to the surface so it is moved as the earth spins beneath it
- 142Why is the Speed of rotation faster at the equator than the poles?Equatorial region has to cover larger distance in the same time as the poles
- 143What is the Ekman spiral?A decaying spiral as you move into the ocean. Less power but further deflection moving in depth.
- 144How does convergence affect nutrient supply?Increased in pressure, downwelling, increase in sea height, low productivity and reduction in nutrient supply
- 145How does divergence affect nutrient supply?Decrease in pressure, upwelling, decrease in height, high productivity and increase in nutrient supply
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- Undergraduate Degree Atmosphere and Ocean Science Fichas sobre Atmosphere Flash Cards, creado por Sammie Bradley el 24/07/2020.
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- Sammie Bradley
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