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| What is the water cycle? | It is the continuous transfer of water between the sea, the land and the atmosphere. It is a continuous cycle with no beginning or end. |
| What are the processes of the water cycle? | Precipitation, interception, infiltration, run-off, evaporation, condensation, precipitation. |
| Give examples of precipitation. | Rain, snow, sleet or hail, falls to the ground. |
| Give examples of interception. | Rain is intercepted by vegetation or buildings. |
| Give examples of infiltration. | Rain seeps into the ground. |
| Give examples of Runs-off. | Rain runs off the surface of the ground as a river or stream. |
| What happens during evaporation? | Energy from the sun evaporates the water. |
| What happens during condensation? | As the air cools it causes clouds. |
| What is a river basin? | A river basin is an area of land drained by a river and its tributaries. |
| What are the features of a river basin? | What are the features of a river basin? |
| What are tributaries? | Smaller rivers flowing into a larger river. |
| What is a watershed? | An area of highland surrounding the river basin. |
| What is a confluence? | Where a river joins another river. |
| What is the source? | The start of a river. |
| What is the mouth? | Where a river meets the sea or an ocean. |
| What happens in the upland source of a river? | A river flows from an upland source where the velocity of water is faster because the river's gradient is steep. The valley has a narrow floor and steep sides (v- shaped). |
| What happens in the middle course of the river? | The middle course of the river has a wider floor and the sides of the valley are more gently sloping. The velocity is slower but the channel is wider as other streams and rivers join it. |
| What happens in the lower course of the river? | The lower course of the river is very gentle sloping, almost flat. The channel is usually at its widest and deepest here because the amount of water flowing within the river is at its greatest. |
| What are the four main processes by which rivers cause erosion? | Abrasion, hydraulic action, attrition and corrosion. |
| What is abrasion? | Abrasion is when large pieces of rock wear way the river banks and bed. |
| What is hydraulic action? | This is when the force of water erodes softer rock. |
| What is Attrition? | This is when sediment particles knock against the bed or each other and break, becoming more rounded and smaller. |
| What is Corrosion? | This is when acidic water in the river erodes rock. |
| What is flooding? | Flooding occurs when a river's channel cannot hold all the water in it and the water spill out onto the flat area of land next to the river. |
| What are the advantages of flooding? | Floods can deposit rich, fertile soil for agriculture and can replenish irrigation channels. |
| What are the disadvantages of flooding? | Floods can destroy food supplies, homes and transport infrastructures. |
| What are the causes of flooding? | Human causes, such as Deforestation and Urbanisation and natural causes such as heavy rainfall and melting snow. |
| How does Deforestation cause flooding? | Cutting down trees causes increased water flowing over the land and rain water reaches rivers faster. |
| How does Urbanisation cause flooding? | Man-made surfaces such as concrete result in increased water flowing over the concrete and rain water reaches rivers faster. |
| What can you do to reduce flooding? | Afforestation and dams. |
| What is Afforestation? | Planting more trees reduces run-off and increase interception. |
| How do dams reduce flooding? | They can significantly reduce the risk of flooding downstream. |
