Unit 9: Global Change
Env. Science · Unit 9 · Paper 2

Global Change unit test

A test on this unit alone, marked as a percentage and a letter grade — for the test your class is actually sitting, rather than for May. Answer everything, then submit once: seeing the answer to question 3 before attempting question 4 makes the final percentage meaningless.

Each paper is built from this unit’s 43 terms and is the same for everyone, so a teacher can assign “Unit 9, Paper 2” and every student sits the identical test. Multiple choice is marked objectively; the written sections you mark yourself against the model answer and rubric.
Suggested time 37 min 34 points0/17 attempted
1

Ocean acidification

2

Why the ozone hole forms over Antarctica

3

Causes of extinction (HIPPCO)

4

The Keeling curve

5

Carbon tax vs cap and trade

6

Why an invasive species succeeds

7

Permafrost and methane

8

Stratospheric ozone depletion

9

Evidence for climate change

10

Range shifts and phenology

11

Why CO₂ matters most despite a low GWP

12

Coral bleaching

Short answer 1. Define or explain: Global warming potential

3 pts

Short answer 2. Define or explain: Which HIPPCO factor is largest

3 pts

Short answer 3. Define or explain: Invasive species

3 pts

Short answer 4. Define or explain: Controlling an invasive species

3 pts

Free response

10 pts

ANALYZE AN ENVIRONMENTAL PROBLEM AND PROPOSE A SOLUTION (WITH CALCULATIONS). Ocelots are small wildcats that were previously found in 25 counties in Texas where shrubland is prevalent. As a result of land use changes, only 74 ocelots remain, in 4 counties. Rodents such as pocket mice are the main food source for ocelots, but ocelots also prey on other small animals such as snakes and lizards. Data for the calculation parts: • Historically 25 Texas counties; today 4 counties. • Expected population growth rate: 2.8% per year. • An ocelot needs 720 grams of food per day; pocket mice average 43 grams each; the ocelot diet is 46% pocket mice by weight. • As urbanization has increased in southern Texas, motor vehicle collisions have become the main cause of ocelot deaths.

A. Identify one environmental consequence that could result from having a smaller population of ocelots.

B. Calculate the percent change in the number of Texas counties where ocelots have been found historically as compared to today. Show your work.

C. Researchers expect the ocelot population to grow at a constant rate of 2.8% per year. Calculate the number of years it will take for the ocelot population to double. Show your work.

D. Pocket mice eat plants in the shrubland, while snakes are carnivores. Explain why the amount of primary production energy available to ocelots would change if ocelots ate only carnivores such as snakes and not pocket mice.

E. Ocelots need 720 grams of food per day. If the ocelot diet consists of 46% pocket mice by weight, calculate how many pocket mice an ocelot would need to consume in one day, assuming each mouse weighs the average 43 grams. Show your work.

F(i). Propose a realistic solution to reduce the number of ocelots killed by vehicles.

F(ii). Justify the solution proposed in part F(i) by explaining an additional advantage, other than reducing the number of ocelots killed by vehicles.