Theme 5 weather, climate and ecosystems Flashcards
What is some evidence for climate change?
Fossils of plants and animals found in places they could not live today, Ice cores show the amounts of CO2 and Methane in the atmosphere have changed, Studies of tree rings showing seasons have varies in the past, historical records like crop yield and paintings for example ice fairs on the river thames during the little ice age.
Causes of Climate change?
Carbon Cycle, Greenhouse effect
What is the Greenhouse effect?
Solar energy enters the Earths atmosphere, solar energy heats the Earths surface which then radiates long-wave energy into the atmosphere, Long-wave energy is easily absorbed by naturally occurring greenhouse gasses for example CO2.
What is an example of naturally occurring climate change?
Milankovitch cycle, tilt of earth whilst orbiting and causing it to receive more/less solar radiation.
Explain Global cooling due to volcanic eruptions:
When a volcano erupts it releases ash and sulphur dioxide that forms an aerosol- tiny droplets that scatter sunlight back into space, reducing the amount of solar energy reaching the earths surface.
What is an example of global cooling due to volcanic eruptions?
Mount Pinatubo, philippines, mean world temp decreased by 0.5 degrees
What is some weather associated with low pressure?
Depressions produce cloudy, rainy, windy weather. Depressions often start in the Atlantic and move eastwards to the UK. As air rises and cools water vapour condenses forming clouds and precipitation.
What is some weather associated with High Pressure?
Low wind speed, stable conditions with no clouds. Anti cyclones usually bring dry hot weather which may lead to drought. Rapidly rising warm weather may lead to convectional rainfall and thunderstorms.
What is convectional rainfall?
When land warms up and heats the air above it, causing the air to expand and rise, when it rises it cools and condenses and large clouds are formed, leading to heavy rainfall
What are some key services that ecosystems provide?
Providing timber, food, clean water, medicines, prevents flooding, spiritual and leisure resources, carbon cycle that maintains the conditions needed for life on Earth.
What are some examples of key services provided by ecosystems?
Taiga; Provide huge sources of timber
Savannah grassland; wildlife attracts tourists helping the local economy
Sand dunes; natural sea defence against floods and storm surges.
How does human activity affect the sand dune system/
Sand dunes may be a place for leisure activity therefore people will trample on the marram grass, exposing the sand which in return can get blown away. Farmers also use sand dunes to graze their animals which increases animal waste absorbing into the ground and disrupting the natural processes. Also in demand for development to build caravan sites, golf courses or housing.
How can ecosystems be managed sustainably?
Selective logging, only cutting down a certain amount of trees in a certain area. Buffer zones, a protected area established around sensitive areas to lessen the impact of human activities on the core. Wild life corridor, link fragments of land so animals can find food and a mate to reproduce. Debt for nature swaps, poor countries can swap their debt with a rich countries and in return protect a special area
