Climate and Water
- The quantity and quality of water available to people depend on a number of physical factors
- Climate has a significant influence on the water supply
- Precipitation
- Temperature
- Wind speed and direction
Physical Factors Affecting Water Supply
Aspect of climate |
How it influences water supply |
Examples |
Precipitation |
Levels vary seasonally and regionally Reliable rainfall needed to maintain supplies Seasonal differences mean storage needed to ensure a year-round supply The global average is 860mm per year but only 23% falls over land |
Arica, in Chile, has the lowest recorded average rainfall of any city in the world at 0.8mm per year Saudi Arabia has the lowest figure for any region, at 66mm per year |
Temperature |
Higher temperatures mean greater rates of evapotranspiration and potential drought Extreme cold can lock water supplies up in ice and snow in winter months, making it less accessible |
Average temperatures in central Saudi Arabia can reach 38℃ in summer 8 of the 37 settlements in Greenland have water supplies classed as poor |
Wind |
Onshore winds bring more humid air over land whereas offshore winds lead to aridity in coastal areas More wind can contribute to higher rates of evapotranspiration and humidity |
Phoenix, Arizona, USA has the lowest average annual wind speeds at 6.2mph contributing to low humidity and an average rainfall of 200mm per year |
Exam Tip
Try and remember a real life example for each factor, such as the ones in this table. This will enable you to back up the points you make and your answers will become rooted in real geography. This will give you more marks for the ‘knowledge and understanding’ element which makes up roughly half of all the marks in your A level.