Please enable JavaScript.
Coggle requires JavaScript to display documents.
SURPLUS IN THE HYDROLOGICAL CYCLE AND CLIMATE CHANGE - Coggle Diagram
SURPLUS IN THE HYDROLOGICAL CYCLE AND CLIMATE CHANGE
DRAINAGE BASIS vunrable to surplus water some areas are mire suseptable then others
▪ Low-lying land, the base of a river valley and estuaries - River flooding can occur along with groundwater flooding as the ground become saturated, therefore any surface close to the water table is vulnerable to flooding.
▪ Urbanised, built environments – Impermeable surfaces increase surface runoff, reducing lag time and so increasing the risk of flash flooding.
▪ Small basins, especially in semi-arid and arid regions - These regions suffer from flash flooding due to very short lag times, which can be hazardous.
MITIGATION AND ADAPYTION TO FLOOD RISK
▪ Afforestation of upland areas - increasing vegetation cover will reduce rapid surface runoff
▪ Restricting construction on floodplains - reducing potential economic and social loss for residents living on flood plain. Also, by reducing urbanisation, there will be maximised levels of interception.
▪ Establishing temporary extra flood plains, in the event of extreme weather - some UK councils have designated football pitches or parks next to the river, to channel some of the storm discharge and reduce the flood risk for towns living close to the flood banks.
CLIMATE CHANGE
ANTHROPOMOROHIC GLOBAL WALMING increased greenhouse gases in the atmosphere This could lead to several different impacts directly affecting the hydrological cycle:
▪ If land and sea surface temperatures continue to rise, the period between ENSO cycles (currently every 2-3 years) could decrease. This would lead to more periodic unusual climates for both South America and Australia.
▪ Increasing average global temperatures would increase rates of evaporation, which could lead to potential droughts and increasing water scarcity..
▪ However, for some locations, a rise in average temperatures will lead to more convectional rainfall and enhanced tropical cyclone or depression intensity. This in turn will cause more intense and periodic flooding.
REDUCE IMPUTTS AND STORES BUT MAY INCREASE OUTPUTS
➔ Less precipitation
➔ Less water available in stores
➔ Reduced size of snow and glacier mass
➔ Water Table drops (height/ capacity of groundwater store) and Aquifer stores deplete
➔ High rates of evaporation
➔ More frequent cyclones and monsoons
CHALANGES
future of drainage basins and the hydrological cycle depends on Climate Change and ENSO cycles (both of which are unpredictable and not well understood)
managing future change is challenging if not impossible!