Enquiry 1 what are the processes operating within the hydrological cycle from global to local scale Flashcards
water cycle
operates on a variety of scales where physical processes control the circulation of water between stores on land, oceans, the cryosphere and atmosphere
type of cycle
closed system with inputs (precip), outputs, stores and flows
driven by solar energy and gravitational potential energy
stage 1
EVAPORATION: water vapour from oceans is lifted and condensed in the atmosphere to form clouds
stage 2
MOISTURE: transported around the globe, some evaporates back into atmos and some percolate the ground to form groundwater
stage 3
Balance of water that remains on the surface is called RUNOFF and is emptied into lakes, rivers and streams which carry it back to the ocean
ocean store
water- 96.9%
residence time- 3,600yrs
Icecaps
water- 1.9%
residence time- 15,000yrs (size dependent)
groundwater
water- 1.1
residence time- up to 10,000 yrs
rivers/lakes
water-0.01
residence time- 2 weeks to 10yrs
blue water
water in rivers/lakes (visible)
green water
water in soil/vegetation (invisible)
deep-seated groundwater
not renewable Sahara desert fossil water result of the pluvial period not reachable
accessible stores
soil moisture
lost to other stores by evap/ transpiration/ groundwater flow
water for life support
2.5% of global water is freshwater
rivers have 0.007% so are a source of conflict/disputes
30% in groundwater/ some fossil water (slow turnover period)
drainage basin
an area of land drained by a river