rest of EQ1 Flashcards
Describe the natural greenhouse effect
The solar radiation emitted from the sun is high frequency and passes through the Earths atmosphere with relative ease.
When the radiation rebounds from the Earths surface, it is of a lower frequency which means it no longer has the same pass-through. Consequently it is absorbed by gasses such as CO2, CH4, H2O
What is the enhanced greenhouse effect
Works in the same way as the natural greenhouse effect however, more low frequency solar radiation is reflected due to the increase in gasses within the atmosphere of greenhouse gasses and
state the: % produced by human activity Warming compared to CO2 %increase in size since 1850 for CO2
89 % of produced
1
30% increase since 1850
state the: % produced by human activity Warming compared to CO2 %increase in size since 1850 for CH4
7% produced
21x compared to CO2
250% increase since 1850
state the: % produced by human activity Warming compared to CO2 %increase in size since 1850 for N2O
3% of produced
250x compared to CO2
16% increase since 1850
state the: % produced by human activity Warming compared to CO2 %increase in size since 1850 for Halo Carbons
1% of produced
3000x warming compared to CO2
% increase is n/a as it is not naturally produced
explain the distribution of temperature and precipitation
The intensity of solar radiation varies due to the curvature of the Earth, at greater latitudes the albedo effect is lower. At higher latitudes albedo is less and hence the solar energy intensity is greater and less spread out, the opposite is true for lower latitudes. solar energy is less intense and more spread spread out.
Different characteristics of the Earths surface also play a role. Darker surfaces such as the tropical rainforest absorb more solar radiation compared to lighter surfaces such as the poles.
Explain how oceans and terrestrial photosynthesis regulates the atmosphere
phytoplankton in oceans sequester CO2 through photosynthesis, this transports about 5-15GT per year from the atmosphere to the ocean
Terrestrial photosynthesis sequesters 100-200 Giga Tons of CO2 per year, some of this is released back into the atmosphere as respiration.
The presence of coral reefs allows for the formation of phytoplankton, the increasing temperatures an pollution killing off the reefs contributes to increased warming as a feedback loop
explain the significance of soil for the carbon cycle
- soil stores 20-30 % of global carbon
- sequesters 2x as much carbon as the atmosphere and 3x as much terrestrial vegetation
- Arid soils store 30 tonnes of carbon per hectare, 800 tonnes per hectare in cold regions
- Mangroves hold 105 of all carbon and they can hold it in for thousands of years due to the fact they are submerged under high tides and are in anaerobic conditions with little to no respiration
- Clay soils also hold more carbon than sandy soils
How significant is the soil store relative to fluxes
carbon fluxes into the atmosphere are 50x greater then the ones into the soil, positive feedback loops increase this effect.
- Furthered by anthropogenic action such as:
- Fracking -Population increase -Technological use increase -Cattle farming -Urbanisation
List the main arguments for the question to explain significance of the soils in the carbon cycle
- soil stores 20-30% of all carbon, 2x more than atmosphere and 3x more than terrestrial vegetation
- carbon in soil keeps it healthy which fuels nutrient cycle and allow faster growth of vegetation which increase sequestration rates, positive feedback loop
- MANGROVES, store for thousands of years due to anaerobic conditions. This means the conditions for respiration are not present / this is however hindered by anthropogenic activity, shrimp farmers and those who catch sea food are draining and clearing mangroves which leads to carbon being released back into the atmosphere
- -Positive feedback loops occurs as a result of carbon removal from soil. Increased carbon content causes increase in temperature which leads to melting of ice which decreases albedo and increases global warming and so on.
- IF just 2% of the worlds mangroves were removed, carbon released will be at 50x the sequestration rate
Name the anthropogenic causes for arising greenhouse gasses
- Combustion of fossil fuels
- deforestation
- loss of soil carbon (cash cropping)
- cattle ranching
- cement/concrete manufacturing
what are the consequences arising from the combustion of fossil fuels
- Increased GHG concentration -> enhanced greenhouse effect, increased global temperature, increased extreme weather events
- production of sulphur dioxide which leads to acid rain, production of black carbon -> particulate matter which causes health problems (1.6 million die from this each year in China)
list main points for the question: explain the effects of warming for specific areas
- The greatest warming is predicted for the arctic, the average arctic temperature has increased by twice the global average over the last 200 years. Snow and ice over will contract meaning less of the suns energy will be reflected. This contributes further to the effects of warming and lead to the thawing of permafrost where about 1,400 gigatons of carbon frozen is in permafrost. As a result more water will be added to arctic rivers which may lead to the extinction of certain arctic species e.g. polar bears
- Another large area expected to face lots of warming is the amazon in Northern Brazil. As a result the warming in northern latitudes will face greater precipitation whereas southern latitudes will face decreases in precipitation. This would decrease the river discharge of the amazon river and cause drastic negative effects for its ecosystem
Name the approximate quantities of Bio-Geo-Chemical stores and fluxes
Terrestrial: -sedimentary rock, 8.3x10^7 PgC, -organic fossil fuels, 1,471 PgC
Oceans: -Intermediate and deep ocean store, 37,100 PgC, -Ocean floor calcareous ooze store, 1750 PgC
Atmosphere: 600PgC
Bio-Geo-Chemical Fluxes: -Photosynthesis, 123 PgC/yr -Atmosphere to ocean, 80PgC/yr, -Respiration and fire, 120PgC/yr
