Presentation on theme: "The Hydrological Cycle"— Presentation transcript:
1 The Hydrological Cycle HYDROSPHEREThe Hydrological CycleBy the end of the lesson you will be able to:Describe the global hydrological cycleCategorise the elements of the movement of water within the drainage basinInputsStorageTransferoutputs
2 The Hydrological Cycle HYDROSPHEREThe Hydrological CycleThis is the system which describes the distribution and movement of water between the earth and its atmosphere.
4 HYDROSPHEREA CLOSED SYSTEMThe 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.
6 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..
7 Inputs and outputs PRECIPITATION - input EVAPOTRANSPIRATION - output HYDROSPHEREInputs and outputsPRECIPITATION - inputPrecipitation occurs with rain, hail, snow, sleet or dew.EVAPOTRANSPIRATION - outputEvapotranspiration as plants breathe (transpire) they loose water vapour to the atmosphere.
8 transfers Percolation: water percolates into the rocks. HYDROSPHEREInfiltration: water seeps downwards into the soil.Percolation: water percolates into the rocks.transfersRUN-OFF / SURFACE FLOWThe rainwater flows, either over the ground (run off / surface flow) into rivers and back to the oceanWater 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.
9 storage Surface storage: water stored in lakes and reservoirs HYDROSPHEREInterception: plants and their leaves collect rainwaterSurface storage: water stored in lakes and reservoirsstorageSoil moisture storageWater stored in the soilGroundwater: Water stored in the porous rocks
10 THE WATER CYCLE BALANCE HYDROSPHERETHE WATER CYCLEBALANCEUsually 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.
11 Complete the diagram Fill in the blanks Colour code the processes HYDROSPHEREComplete the diagramWater tableVariable levelINPUTSSTORAGETRANSFERSOUTPUTSFill in the blanksColour code the processes
12 Complete the diagram Fill in the blanks Colour code the processes HYDROSPHEREComplete the diagramVegetation storageevaporationprecipitationSurface run-offOUTPUT TO SEAevapotranspirationinterceptionpercolationStem flowinfiltrationGroundwater flowChannel storageThrough flowSoil water storageGroundwater storageSurface storageChannel flowWater tableVariable levelINPUTSSTORAGETRANSFERSOUTPUTSFill in the blanksColour code the processes