Carbon 6.3 Flashcards
the role of carbon is the natural greenhouse effect
- Solar energy enters the atmosphere
- Only a little short-wave radiation is absorbed in the atmosphere
- As this short-wave energy passes through the atmosphere it might hit dust particles or water droplets and be scattered or reflected
- Solar energy heats the Earth’s surface, which then radiates long-wave heat energy into the atmosphere
- Some long wave energy escapes into space
- Long-wave energy is quite easily absorbed by naturally occurring greenhouse gases in the atmosphere. Of these, carbon dioxide is by far the most abundant
Nitrous oxide
- From car exhausts
- Power stations
- Fertilisers
- 3% of all gases
Carbon dioxide
- Burning of fossil fuels such as coal, oil and gas for domestic, industrial and transport use
- 89% of all gases
- Largest radiative forcing affect
methane
- Released from waste dumps, farms and rice paddy fields
- 21 times more powerful
- 7% of all gases
halo carbons
- These are the most damaging
- Only 1% but 3000 times more powerful
- From aerosols and fridges
Why is the heating uneven across the earth?
- Angle of the incoming radiation is overheard
- Higher concentration and more efficient heating at the equator
- Same amount of radiation has to heat a larger area due to angle it hits poles
What other factors affect the amount of solar energy that is absorbed at the earth’s surface?
-the albedo effect
What processes occur to reduce the temperature extremes at the equator and the poles?
- Atmospheric circulation
- Ocean currents
distribution of temperature around the world
- The amount of solar energy (solar insolation) reaching the Earth’s surface varies at different locations – which then influences the temperature
- The angle of the sun’s rays makes solar insolation intense at the Equator, but dispersed at a wide area at the Poles
- Different characteristics of the earth’s surface also affects how much heat is absorbed and reflected (albedo) - snow reflects heat and dark forests absorb it
- Heat is distributed around the globe by air movement caused by both pressure differences and ocean currents.
distribution of precipitation around the world
- The heating of the earth’s atmosphere and surface controls the temperature, pressure, movement and moisture content of the air
- Warm air rises and cools leading water vapour to condense and clouds to form
- Solar radiation is more intense over the equator, so convection and low-pressure systems dominate here – precipitation is high
- Air pressure rises around 30 degrees north and south, precipitation decreases
- Mid latitudes are where air masses of different characteristics meet and low-pressure systems bring rainfall
- Near the poles, precipitation falls as the air cools further and is dense and dry
- Regional and seasonal variates occur – due to the effects of relief and the migration of global pressure patterns and wind systems as the sun moves north and south
Why has the concentration of methane increased?
From 1984, methane concentration has gradually increased from 1625 to 1850 in 2020. One reason for this increase is due to higher demand for farming products for food, this is caused by the increase in middle class in lots of emerging countries so therefore lots of land is converted to rice paddy fields which creates a loss of a carbon sink.
Photosynthesis
• Photosynthesis is the process by which green plants and some other organisms use sunlight to synthesise (extract) nutrients from carbon dioxide and water.
why is photosynthesis important?
-Photosynthesis by terrestrial (land) and oceanic organisms plays an essential role in keeping CO2 levels relatively constant and thereby helping to regulate the Earth’s temperature.
What is NPP?
Net primary productivity – a measure of the rate of photosynthesis in an ecosystem and therefore gives a measure of the size of the carbon sink
What is app controlled by?
– is controlled by climate and availability of nutrients
threats for tundra
rising temperatures
threats for boreal forest
logging
threats for temperate deciduous forest
logging, development (urbanisation, industrialisation and agriculture)
threats for temperate grassland
conversion to arable and pastoral farming
threats for savannah grassland
conversion to arable and pastoral farming