What physical factors determine the supply of water? G4 Water Key Idea 2.1
Rivers only 2% of surface freshwater
The parts of the water cycle
Global values of the water cycle
Climate determines where rain falls – Highs and Lows
Freshwater availability varies at different scales
Continent population and fresh water
Upland Wales – temperature and rainfall
Craig Goch Wales - a good reservoir site – why?
London SE England – Temperature and Rainfall
England and Wales – matching supply and demand.
Water Transfer – proposal (controversial)
Water Balance
Botswana – Rainfall Total, seasonality, variability
India – climate, river discharge, aquifers
Relief – river basins
Climate Change – ultimately reduced river flows in some areas Global warming will melt most Andean glaciers in the next 30 years, scientists say, threatening the livelihood of millions of people who depend on them for drinking water, farming and power generation.
Aquifers and groundwater in the UK
Thames Basin - artesian
See pie chart c).
Water supply is not always top quality. Human impact.
Human impact on supply. Lake Chad.
Water scarcity – physical and economic.