Each answer has equal weight, one point each.

1. In an average year, 100 cm of rain falls on a catchment area of 900 km2.

a. What is the volume of water received during an average year in cubic meters?
b. What is the same volume expressed in gallons?

2. We define the residence time of a reservoir in steady-state (no change in total volume) as the total volume of the reservoir divided by the inflow or ouflow rate. [tR = V/I] The polar ice caps (area = 1.6 x 107 km2) are estimated to contain a total equivalent volume of 2.4 x 107 km3 of liquid water. The average annual precipitation over the ice caps is estimated to be 5 inches per year.

a. Estimate the residence time, tR, of water in the polar ice caps, assuming that their overall volume remains constant in time.

3. In an average year, a small wooded catchment (area = 300 ha) receives 950 mm of precipitation. The catchment is drained by a stream, and a continuous record of stream discharge is available. The total amount of surface-water runoff for the year, determined from the stream discharge record, is 1.1 x 106 m3.

a. What is the volume of water (m3) evapotranspired for the year, assuming steady-state (no change in water storage in the catchment)?
b. What is the depth of water (mm) evapotranspired for the year (again assuming steady-state)?
c. What is the runoff ratio (Q/P) for the catchment?
d. The sum of all stream channel lengths in the catchment is 12 km. What is the drainage density of the catchment?
e. Assume now that the catchment is deforested so that evapotranspiration is reduced by 1/3 and the catchment is no longer at steady-state. What is the change in storage, ΔS?

4. One of the IPCC prediction models estimates that the average air temperature will rise by 3.7 °C by the year 2100.

a. If the 20th-century combined (over land and sea) average air temperature was 14.8 °C, what will be the change in saturation vapor pressure from time 1 (20th century) to time 2 (year 2100)?

b. What practical difference does this make in terms of moisture in the atmosphere, and, consequently, potential for rainfall?

Each answer has equal weight, one point each. 1. In an average...