4. Despite its importance, water only makes up 0.02% of Earth’s mass
This is all the world’s
water gathered into
one sphere – a
surprisingly small
amount.
Video here – from 4.24
8. What are the Physical Factors
controlling water supply? (p34)
• Physical factors effecting the Hydrological
Cycle
1. Climate
2. River systems
3. Geology
9. 4. Seasonality
• Precipitation patterns vary throughout the year. For
example Vancouver receives much of its rainfall
between October and March with less in the
summer.
• Plants use water most in the spring
(evapotranspiration) and this leads to an unbalanced
supply and use of water.
• Globally the same imbalance can occur causing areas
to be particularly dry in their summer and wet in
their winter.
10. Fresh water supply is finite
• Finite resource of water, limited amount each
year.
• Video here
