Climate Change:
- Greenhouse gases like carbon dioxide are released from human activities such as burning fossil fuels
- This means more sunlight is trapped by the atmosphere and the planet is warming slowly
- This will change the world’s climates (and therefore weather)
- The main changes will be variations in precipitation and temperatures: more droughts or more floods will result
- The water cycle will change in different ways in different areas
- In the UK, summers will be hotter, more droughts, but also more intense rainfall and storms, then flooding. Winters milder, more rain, and more floods.
- Tropics will have more extreme weather e.g. droughts or flooding
- Artic areas will warm more, therefore less cryosphere results
Climate Change Affecting
Stores & Flows:
- Snow and glacier mass is shrinking around most parts of the world, such as the Alps in Europe and Himalayas, as temperatures rise
- Short term this might increase channel flow, but long term it will decrease the cryosphere stores and reduce flows from them
- Also in the cryosphere, permafrost areas will shrink.
- Permafrost is areas of land that where the soil below 1 metre deep is permanently frozen, the upper layer may thaw in the summer
Uncertainties:
- Uncertainty means not being able to know or predict accurately the events of the future
- Uncertainties in climate change and water cycle include we don’t know where and when and how bad droughts and floods will be. The further into the future, the more uncertain scientists are.
- Uncertainty reasons include: Climate science is extremely complex and hard to model with computers; We don’t know what future emissions will be; e.g. more electric cars? International agreements like Kyoto Protocol and other factors like ENSO are impossible to predict well
The Future & Water
Security:
- ENSO and climate change will cause a higher frequency and magnitude of flooding and droughts.
- This will affect the ability to access ‘safe, affordable, clean, abundant water to meet needs’ i.e. ‘water security’.
- S cientists, planners & engineers, charities, governments (key players in water security) try to ‘project’ future needs of water. This means predict how much will be needed in coming months/years.