Hazards at plate boundaries
- moderate earthquakes
- volcanoes, not very explosive or dangerous (basalt lava)
- destructive earthquakes
- frequently occuring weak earth tremours
- no volcanoes
- composite volcanoes with violent, powerful eruptions (andesite lava)
- violent earthquakes
- the earthquakes can cause tsunamis
Factors affecting biomes
Altitude: every 100m you go up, temperature decreases by 1'c
Distance from the sea: usually wetter by the sea and drier inland
Geology: rock type and the filtration of the ground will affect the distribution of biomes
Human actions: human actions such as deforestation will affect biomes as land is cleared and used for something else
Why is the future climate uncertain?
- We do not know if people will change their lifestyles- e.g. switching to hydrogen cars or using public transport more often.
- We do not know if more renewable resources will be used or if we will continue to exploit fossil fuels.
- We cannot be sure about the effects of global warming on climate.
Goods and services that biomes provide
- Raw materials e.g. wood
- Medicines e.g. St Johns Wort for treating depression
- Food e.g. nuts and berries
- Production of humus (made from humification, broken down plant matter that provides valuble nutrients for the soil.
- Regulation of the atmosphere- plants remove carbon dioxide and let out oxygen.
Evaporation- from stores, such as rivers, lakes, oceans
Transpiration- evaporation off of the leaves of plants
Condensation- clouds form
Precipitation- water falls in different forms, such as rain, hail, snow
Surface runoff- flow of water when the soil is infiltrated to full capacity
Through flow- movement of water through the rocks
Ground water flow- the water that has infiltrated the ground
Human impact on the hydrological cycle
Overabstraction: when humans take too much water out of groundwater stores, like aquifers which results in the water cycle being affected e.g. streams drying up.
Deforestation: less interception which means water gets into stores more quickly making them more prone to get too full. Also, less trees means less transpiration which will also affect the water cycle.
Industry: chemicals and other waste can end up polluting wqater supplies.
Hydroelectric power: dams built for hydroelectric power can significantly affect rivers
A fragile environment is one that is easily disturbed and difficult to restore, lacking in natural resilience.
Defining hot arid and polar regions
Hot arid regions: are areas that have high temperature and low rainfall. These are either semi arid, with 250-500mm of rain a year or deserts, which have less thatn 250mm of rain a year,
Semi arid- the Sahel
Desert- the Sahara
Polar regions: are areas that have extreme cold. These are either glacial arteas that are covered by ice or places that have frozen soil.
Covered by ice- Greenland
Frozen soil- Alaska
Coastal Engineering methods
- Planting vegetation
- Beach nourishment- replenishing the sediment on the beach that has been removed by longshore drift or erosion
- Rock armour- rocks at the base of cliffs
- Sea wall- concrete wall at the base of a cliff
- Groynes- wooden barriers built perpendicular to the beach to prevent longshore drift
- Introduced in 1997 by the UN
- Aims to reduce the amount of greenhouse emissions produced by developed countries
- Not expected of developing countries because they need to develop- no fixed limits of emissions for countries like Kenya
- Has the support of most countries apart from the USA
- Does not support the protocol because USA believes that by reducing their emissions their economy will be severly effected
- More than 150 countries currently support it