Water, carbon, climate and life on Earth Flashcards
How are the water and carbon stores and cycles essential for life?
1) Carbon is a fundamental building block of life- all living things contain carbon.
Water is also fundamental to life- all living things need water to survive.
2)Photosynthesis requires both inputs and outputs of water and carbon.
3) Water is present in the atmosphere as water vapour, and carbon exists as carbon dioxide and methane. These are greenhouse gases- they cause a natural greenhouse effect that prevents some energy from into space and reflects it back to earth.
This causes temperatures on earth to be higher than they would otherwise be without natural greenhouse effects the Earth would be frozen and uninhabitable.
4) Human activities are increasing the concentration of greenhouse gases in the atmosphere.
Why are both the water and carbon cycle dependent on each other?
> Carbon combines with water in the atmosphere. This allows chemical weathering, which removes carbon from the atmosphere.
> Water is needed for photosynthesis, which removes carbon from the atmosphere.
> The amount of co2 in the atmosphere affects global temperatures, which affects the amount of evaporation that can take place, which affects the amount of precipitation.
How does climate change affect life on Earth?
Climate change is predicted to have major impacts on plants, animals, and people, for example:
1) The patterns of precipitation are expected to change- wet areas are expected to get wetter and drier areas are expected to get drier. This could cause water shortages in some areas, which could lead to conflicts in the future.
2) Extreme weather events are expected to become more common. Less developed countries may struggle to deal with the impacts.
3) Agricultural activity will decrease in some areas, which could lead to food shortages.
4) Sea levels are exected to rise further. This will flood coastal and low-lying areas.
5) The arrival of new species in some areas may damage the ecosystem, and some species may become extinct
6) Plankton numbers may decline if temperature increases, which will have a knock-on effect on food chains.
How do humans try to influence/change the carbon cycle?
1) Humans have influenced the carbon cycle for centuries, particularly by extracting and burning fossil fuels.
There is now 40% more carbon in the atmosphere than there was in 1750.
2)The intergovernmental Panel on Climate Change (IPCC) is an International organisation set up by the UN to share knowledge about climate change. The IPCC states that countries need to reduce the amount of co2 emitted by human activities in order to prevent large temperature rises.
People try to mitigate the impacts of climate change by reducing transfers of carbon to the atmosphere.
These measures can be at a range of scales, for example:
Individual:
> People can choose to use their cars less and buy more fuel efficient cars.
>People make their homes more energy efficient e.g. with double glazing, insulation and more efficient appliances.
Regional and National:
> Governments can reduce the reliance on fossil fuels for heating and powering homes the increasing the availability and reducing the cost of renewable energy sources such as wind, tidal and solar.
> Afforestation and restoring degraded forests can increase carbon uptake by the biosphere.
> Planners can increase the sustainability of developments by improving public transport and creating more green spaces.
>Governments invest in carbon capture and storage ( co2 emitted from burning fossil fuels is captured and stored underground)
Global:
>Countries can work together to reduce emissions. For example the Kyoto protocol (1997) and the Paris agreement (2015) are international treaties to control the amount of greenhouse gases released.
> There are also international carbon trading schemes. Countries and businesses are given a limit on the emissions they can produce- if they sell less they can sell the extra credits, if they produce more they need to buy more credits.
What’s the Paris agreement?
