The Hydrological Cycle HYDROSPHERE The Hydrological Cycle By the end of the lesson you will be able to: Describe the global hydrological cycle Categorise the elements of the movement of water within the drainage basin Inputs Storage Transfer outputs
The Hydrological Cycle HYDROSPHERE The Hydrological Cycle This is the system which describes the distribution and movement of water between the earth and its atmosphere.
HYDROSPHERE
HYDROSPHERE A CLOSED SYSTEM The hydrological cycle is a good example of a closed system: the total amount of water is the same, with virtually no water added to or lost from the cycle. Water just moves from one storage type to another.
DRAINAGE BASIN HYDROSPHERE PRECIPITATION BASIN INFILTRATION evapotranspiration INFILTRATION SURFACE STORAGE INTERCEPTION PERCOLATION THROUGH FLOW CHANNEL FLOW SURFACE RUN-OFF GROUNDWATER FLOW
WATER MOVEMENT HYDROSPHERE The movement of water in a basin relates to the permeability of the underlying rock. If a rock is impermeable it does not allow water to pass through it. Water in impermeable areas flows across the ground surface. A permeable rock allows water to pass through it and may be of two types:- Pervious rocks (eg: carboniferous limestone) contains joints (cracks) which allow water to flow downwards. Porous rocks (eg: chalk) have small pores (air spaces) which allow water to pass through the rock itself. .
Inputs and outputs PRECIPITATION - input EVAPOTRANSPIRATION - output HYDROSPHERE Inputs and outputs PRECIPITATION - input Precipitation occurs with rain, hail, snow, sleet or dew. EVAPOTRANSPIRATION - output Evapotranspiration as plants breathe (transpire) they loose water vapour to the atmosphere.
transfers Percolation: water percolates into the rocks. HYDROSPHERE Infiltration: water seeps downwards into the soil. Percolation: water percolates into the rocks. transfers RUN-OFF / SURFACE FLOW The rainwater flows, either over the ground (run off / surface flow) into rivers and back to the ocean Water flows through the soil back to the sea as through-flow. Then returns back to the sea flowing through the bed rock as ground-water flow.
storage Surface storage: water stored in lakes and reservoirs HYDROSPHERE Interception: plants and their leaves collect rainwater Surface storage: water stored in lakes and reservoirs storage Soil moisture storage Water stored in the soil Groundwater: Water stored in the porous rocks
THE WATER CYCLE BALANCE HYDROSPHERE THE WATER CYCLE BALANCE Usually the water cycle is in balance, and the amount of precipitation falling will slowly soak into the ground and eventually reach the rivers. However, if rain falls for a long period of time or if the ground is already soaked or saturated with water then the chance of flooding is increased.
Complete the diagram Fill in the blanks Colour code the processes HYDROSPHERE Complete the diagram Water table Variable level INPUTS STORAGE TRANSFERS OUTPUTS Fill in the blanks Colour code the processes
Complete the diagram Fill in the blanks Colour code the processes HYDROSPHERE Complete the diagram Vegetation storage evaporation precipitation Surface run-off OUTPUT TO SEA evapotranspiration interception percolation Stem flow infiltration Groundwater flow Channel storage Through flow Soil water storage Groundwater storage Surface storage Channel flow Water table Variable level INPUTS STORAGE TRANSFERS OUTPUTS Fill in the blanks Colour code the processes