2. Global Water Budget

Try these first

1. 1.

   What is the largest reservoir of water on Earth?

   Hint

   Think about where most of the Earth's water is stored.

2. 2.

   Define 'precipitation'.

   Hint

   Consider what you see falling from the sky.

3. 3.

   What percentage of water on Earth is found in oceans?

   • 50%
   • 75%
   • 96.5%
   • 25%

   Hint

   Think of the largest body of water you know.

4. 4.

   True or False: Freshwater sources are more abundant than ocean water.

   • True
   • False

   Hint

   Remember the statistics we discussed earlier.

5. 5.

   Assume an average area of a region receives 1,000 mm of rainfall annually. If 70% of this water is returned to the atmosphere by evapotranspiration, calculate the net water available for runoff.

   Hint

   Subtract evapotranspiration from total precipitation.

6. 6.

   Given that climate change is projected to decrease precipitation by 20% in a region, how would that impact the annual water budget if current precipitation is 500 mm?

   Hint

   Calculate the percentage decrease and subtract it from the current precipitation total.