5.6 Flashcards
What are inputs into the hydrological cycle?
Precipitation (snow, rail, hail and sleet)
How does climate change affect inputs, outputs and transfers in drainage basin hydrological cycle?
- A reduction in precipitation will lead to a reduction of water stored in soil/rivers/lakes.
- Glacial mass will also decrease.
- Outputs such a evapotranspiration will be higher temporarily, until levels of available water falls.
- transfers affected, as a rise by 1 degree in temperatures could increase global run-off by 40%.
What happened in the Sahel region during the 1970s and 1980s?
A decline in 40% of rainfall down from between 100-600mm annually. This lead to severe drought, poverty and civil war. This cause famine.
What are Sahel doing to overcome the consequences of the severe drought?
Sahel are planning to convert the dry landscape to productive farmland, through the process of ‘re-greening’.
- Also used in Malawi, Ethiopia and Niger.
- Farmers can benefit from increasing yields
What is re-greening?
Converting dry landscapes to productive farmland. This is a restoration technique that involves planting trees and bushes.
What is another phrase for re-greening?
Farmer-managed natural regeneration (FMNR)
What are the positives of re-greening?
- increased yield
- natural regeneration of water-retaining shrubs and trees
- low-cost reforesting
Why is there uncertainty of the impact of climate change on water systems?
- We can’t predict whether wetter or drier weather will become more frequent
- Different places will have different likelihood’s and risks of extreme weather.
- This could include flooding, droughts or cyclones.
- One degree temperature rise will increase the amount of moisture held in the atmosphere by 7%.
- This will have a knock on effect, as the potential for heavy rainfall increases.
- Flooding in central Africa, South America and Asia will increase
- Flooding is likely to decrease in Europe.
