APES Final Exam FRQ's questions
with complete solution
FRQ1: (a) Explain how an increase in the amount of dissolved CO2 in ocean water results in a
decrease in the pH of ocean water - ANS ✔when carbon dioxide dissolves in the ocean it forms
the acid H2CO3.
FRQ1: (b) Explain why the movement of carbon into the ocean has been increasing since 1850. -
ANS ✔the concentration of carbon dioxide has greatly increased because of burning of fossil
fuels.
FRQ1: (c) In order to model the effects of ocean acidification on coral reefs, some simplifying
assumptions can be made. Use the assumptions in the table below to perform the calculations
that follow.
(i) Calculate the current annual global increase in volume, in m3, of CaCO3 in coral reefs. Show
all steps in your calculation. - ANS ✔7.5 × 10⁸ m³/year
FRQ1: (c) In order to model the effects of ocean acidification on coral reefs, some simplifying
assumptions can be made. Use the assumptions in the table below to perform the calculations
that follow.
(ii) Calculate the current annual global increase in mass, in kg, of CaCO3 in coral reefs. Show all
steps in your calculation. - ANS ✔1.5 × 10¹² kg/year
FRQ1: (c) In order to model the effects of ocean acidification on coral reefs, some simplifying
assumptions can be made. Use the assumptions in the table below to perform the calculations
that follow.
, (iii) Because of ocean acidification, it is expected that in 2050 the mass of CaCO3 deposited
annually in coral reefs will be 20 percent less than is deposited currently. Calculate how much
less CaCO3, in kg, is expected to be deposited in 2050 than would be deposited if ocean water
pH were to remain at its current value. - ANS ✔3 × 10¹¹ kg
FRQ1: (d) Identify and describe one likely negative environmental impact of the loss of coral
reefs. - ANS ✔loss of habitat for marine animals like fish who use coral reefs as shelter or
breeding grounds.
FRQ1: (e) Identify one environmental problem (other than one due to ocean acidification or loss
of coral reefs) that affects marine ecosystems on a global scale. - ANS ✔overfishing which
depletes fish populations
FRQ2: (a) Based on the rate cited above, calculate the expected increase in sea level, in meters,
during the next 50 years. - ANS ✔0.15m
FRQ2: (b) Identify TWO phenomena that result from an increase in global mean atmospheric
temperature and that contribute to increases in sea level. For each phenomenon that you
identify, explain how it causes sea level to increase. - ANS ✔melting of glaciers which increases
the amount of water in the ocean after the ice melts. Also thermal expansion because as the
water gets warmer in the ocean the volume increases.
FRQ2: (c) Describe TWO environmental impacts that increasing sea level will have on an
estuarine ecosystem such as those in the Mississippi Delta, Chesapeake Bay, and San Francisco
Bay. - ANS ✔flooding, the increase in sea level could cause a migration of water into the wetland
around the estuary. Also salinity of water could change and possibly lead to species loss.
FRQ2: (d) Although sea level has been rising for over a century, human populations in coastal
areas have increased dramatically during this period.
with complete solution
FRQ1: (a) Explain how an increase in the amount of dissolved CO2 in ocean water results in a
decrease in the pH of ocean water - ANS ✔when carbon dioxide dissolves in the ocean it forms
the acid H2CO3.
FRQ1: (b) Explain why the movement of carbon into the ocean has been increasing since 1850. -
ANS ✔the concentration of carbon dioxide has greatly increased because of burning of fossil
fuels.
FRQ1: (c) In order to model the effects of ocean acidification on coral reefs, some simplifying
assumptions can be made. Use the assumptions in the table below to perform the calculations
that follow.
(i) Calculate the current annual global increase in volume, in m3, of CaCO3 in coral reefs. Show
all steps in your calculation. - ANS ✔7.5 × 10⁸ m³/year
FRQ1: (c) In order to model the effects of ocean acidification on coral reefs, some simplifying
assumptions can be made. Use the assumptions in the table below to perform the calculations
that follow.
(ii) Calculate the current annual global increase in mass, in kg, of CaCO3 in coral reefs. Show all
steps in your calculation. - ANS ✔1.5 × 10¹² kg/year
FRQ1: (c) In order to model the effects of ocean acidification on coral reefs, some simplifying
assumptions can be made. Use the assumptions in the table below to perform the calculations
that follow.
, (iii) Because of ocean acidification, it is expected that in 2050 the mass of CaCO3 deposited
annually in coral reefs will be 20 percent less than is deposited currently. Calculate how much
less CaCO3, in kg, is expected to be deposited in 2050 than would be deposited if ocean water
pH were to remain at its current value. - ANS ✔3 × 10¹¹ kg
FRQ1: (d) Identify and describe one likely negative environmental impact of the loss of coral
reefs. - ANS ✔loss of habitat for marine animals like fish who use coral reefs as shelter or
breeding grounds.
FRQ1: (e) Identify one environmental problem (other than one due to ocean acidification or loss
of coral reefs) that affects marine ecosystems on a global scale. - ANS ✔overfishing which
depletes fish populations
FRQ2: (a) Based on the rate cited above, calculate the expected increase in sea level, in meters,
during the next 50 years. - ANS ✔0.15m
FRQ2: (b) Identify TWO phenomena that result from an increase in global mean atmospheric
temperature and that contribute to increases in sea level. For each phenomenon that you
identify, explain how it causes sea level to increase. - ANS ✔melting of glaciers which increases
the amount of water in the ocean after the ice melts. Also thermal expansion because as the
water gets warmer in the ocean the volume increases.
FRQ2: (c) Describe TWO environmental impacts that increasing sea level will have on an
estuarine ecosystem such as those in the Mississippi Delta, Chesapeake Bay, and San Francisco
Bay. - ANS ✔flooding, the increase in sea level could cause a migration of water into the wetland
around the estuary. Also salinity of water could change and possibly lead to species loss.
FRQ2: (d) Although sea level has been rising for over a century, human populations in coastal
areas have increased dramatically during this period.
