Question 1

According to the Rockstrom paper,which of Earth's critical "life-support" systems has been perturbed most beyond Rockstrom's "safe" level?

Accepted Answer

A)  Climate change 
B)  Biodiversity 
C)  Phosphorous cycle 
D)  Ocean acidification

Question 2

Scientists say that that the global rate of terrestrial net ecosystem production (NEP)is approximately 56.4 Pg of carbon per year.However,there may be 30% or more uncertainty in these rates.What does that mean?

Accepted Answer

A)  That the NEP is exactly 56.4 Pg of carbon per year and that it does not fluctuate 
B)  That the global NEP is inferred from data, and that there may be plus or minus 30% of 56.4 Pg of carbon per year 
C)  That the global NEP is absolute, and that it will likely be higher than 56.4 Pg of carbon per year 
D)  That the NEP is not reliable because there is 30% or more uncertainty. Therefore we should not trust the estimate.

Question 3

If Earth's oceans are carbon dioxide sinks,that means that carbon dioxide should remain in oceans infinitely.Is that accurate?

Accepted Answer

A)  Yes, the oceans are a sink and no carbon dioxide is ever released. This process explains ocean acidification. 
B)  No, the oceans are not sinks although they do assimilate carbon dioxide. 
C)  No, the carbon dioxide assimilated into the deep ocean in the Atlantic will eventually surface elsewhere and be released back into the atmosphere. 
D)  Yes, the oceans are a sink for carbon dioxide, but only in the Southern Indian and Pacific Oceans. In a few decades the carbon dioxide is assimilated by marine animals and released when they die.

Question 4

The IPCC shows what levels of carbon dioxide were in the Earth's atmosphere for the last 10,000 years.How are they able to do this?

Accepted Answer

A)  They extrapolate data from recent measurements 
B)  They use tree rings 
C)  They use bubbles of atmospheric gas trapped in ice samples 
D)  The data are from a model and not actual data

Question 5

The rate of phosphorous flow through the global environment is three times faster now than before the industrial and agricultural revolutions.The main problem with this accelerated cycle is that?

Accepted Answer

A)  It results in acidification of the oceans 
B)  It causes drastica alteration of ocean currents 
C)  It causes eutrophication of freshwater lakes 
D)  It initially slows the growth of freshwater vegetation

Question 6

You might say that fertilizer has an indirect negative effect on amphibians because:

Accepted Answer

A)  Fertilizer promotes algae which in turn promotes an intermediate host for a harmful amphibian parasite 
B)  Fertilizer directly disrupts amphibian development 
C)  Fertilizer promotes algae which is what frog tadpoles feed on 
D)  Fertilizer promotes algae which in turn produces more frog predators

Question 7

What patterns do we see historically for the release of carbon dioxide to the atmosphere from tropical and temperate forests?

Accepted Answer

A)  Deforestation in temperature forests remains a source of release even today 
B)  Around 1960 deforestation in temperate forests became less of a problem 
C)  Tropical forest emissions peaked in the 1990s but are still a major concern today 
D)  Temperate forest are likely still deforested at the same rate as tropical forests today

Question 8

Sulfur pollution was primarily responsible for what environmental problem in North America and Europe?

Accepted Answer

A)  Eutrophication 
B)  Desertification 
C)  Desalinization 
D)  Acid rain

Question 9

Which of the following statements is correct?

Accepted Answer

A)  Hydro electricity accounts for greater than a fifth of the non-renewable sources of energy used in 2010. 
B)  Coal and Oil represent greater than 50% of the total percentage of non-renewable resources consumed. 
C)  Wood is considered a non-renewable source of energy 
D)  All of the above

Question 10

As carbon dioxide in the atmosphere increase and global temperature rises,what can be expected?

Accepted Answer

A)  The ocean sink for atmospheric carbon dioxide will change 
B)  The terrestrial ecosystem sink for atmospheric carbon dioxide will change. 
C)  We will be able to predict with accuracy how these changes will occur 
D)  We will NOT be able to predict with accuracy how these changes will occur

Exam 12: Global Biogeochemical Cycles and Their Alteration by Humans