6/8 mark questions

explain why land use changes can increase floodrisk

1. deforestation - infiltration less so more run off increasing discharge ie amazon

2. urbanisation - impermeable surfaces reduce infiltration and increase run off ie london

explain why the price of water varies globally

1. obtaining cost - difficult/expensive to obtain ie saudi arabia

2. management - neoliberal view ie bolivia

explain how the physical features of a drainage basin affect the shape of storm hydrographs

1. geology - impermeable flashy, permeable subdued

2. drainage density - high flashy, permeable subdued

explain why human actions often increase water insecurity

1. agricultural contamination - farm run off, reduces water quality for drinking and expensive treatment ie mississipi

2. groundwater overabstraction - not recharged reduces LT availability ie ogalala

explain the contribution of human activity to the risk of drought

1. deforestation - reduced evapotranspiration less humidity and water recylcing reduces rainfall (+FL) ie amazon

2. aquifer overabstraction - faster than recharges ie ogallala

explain how adaptation strategies like water conservation may help communities cope with a changed climate

1. water conservation and recycling - diff purposes, no initial costs and saves water bills

2. RWH - captures and stores ie singapore

explain how water insecurity can cause both social and economic problems

1. industry decline - cooling, cleaning and manufacturing. factories close so less FDI ie india

2. sanitation and health - waterbourne diseases and workforce productivity ie SSA

explain why hard engineering may increase the risk of river flooding in some places

1. dams - fill beyond capacity, emergency releases ie edenville

2. channel straightening - reduces natural storage capacity, increases discharge ie mississippi

explain how the global hydrological cycle operates as a closed system

1. drivers - sun drives evaporation and cryosphere melting, gravity stops water vapour escaping into space, means total water remains same

2. fluxes - definition, examples, water never enters or leaves just changes stores

explain why a drainage basin can be regarded as an open system

1. external inputs - water from outside boundaries, main is precipitation and can cross watershed to enter

2. humans - amount stored and as run off can change ie urbanisation and deforestation

explain how changing weather systems can lead to an increased likelihood of drought

1. blocking highs - anticyclones

2. el nino - tradewinds normally vs el nino