Prelim 2 Flashcards
According to UNESCO, how many marine species face the possibility of extinction by the end of the century if humans continue without significant change in how it treats the oceans?
50%
How much of the ocean surface has been set aside as environmentally protected areas?
1%
Which two groups of marine organisms are especially threatened with species extinctions at this time?
sharks and corals
Which statement best defines Net Primary Production?
the net difference between photosynthesis and respiration
The compensation light level refers to the light level where
net primary production is zero
Subtropical gyres have low levels of primary production per square meter because
??? none of the above
Why is primary production higher in the eastern equatorial Pacific than in the western equatorial Pacific?
the thermocline is shallower in the eastern equatorial Pacific than in the western Pacific
What accounts for the year-round high levels of primary production in coastal regions?
enhanced tidal mixing over shallow continental shelf regions
Which is true about the critical depth?
it is the depth at which the time phytoplankton spend below compensation depth losing carbon just balances the time they spend above gaining carbon, resulting in 0 net primary production
What percent of global primary production takes place in the ocean?
50%
Oceanographers classify organisms into broad groups based on
- autotrophic
- heterotrophic
- body size
The exploitation efficiency of the protozoan grazer community in tropical regions is expected to be
high
The main reason that coastal upwelling regions have much higher amounts of harvestable fish production each year is because
none of the above
Prochloroccus
the main contributor to primary production in open-ocean oligotrophic environments
The biological carbon pump is most efficient in
eutrophic conditions
What typically sets the lower limit in the elevation within the rocky intertidal for a given species?
competition with other species or predation by other species
What prevents a single rocky intertidal species from eventually out-competing all other species and becoming the only species in the rocky intertidal?
Intermediate physical disturbance, such as big storm waves, wipes the rock clean and restarts the whole process of competition among all species
What happens to the abundance of kelp forests when sea otter abundance increases?
kelp forest increases
What is coral bleaching?
this occurs as a result of the breakdown in the symbiotic relationship between the coral and its zooxanthellae
Coral bleaching and the subsequent coral death begins when normal ocean temperatures are
increases by about 1% for a few weeks
With an epic scale effort to rapidly de-carbonize the global energy system and limit global warming to 1.5C, what percentage of coral reefs will still be lost?
70-90%
What percentage of coral will be lost if global warming reaches 2C?
100%
Which of the following comes closest to representing the earliest form of whale Pakicetus?
wolf
Which source of underwater sound may be the greatest threat to whale population survival?
ambient noise from commercial ship traffic
Which of the following nations are currently hunting whales in large numbers?
Norway, Iceland, and Japan
The two opposing forces and or energies that determine the three phases of water are
H bonds and thermal kinetic energy
If you added an equal amount of heat energy to the ocean, atmosphere and land, which one would you experience the smallest temperature change?
ocean
How much of the excess heat that has accumulated in the earth system as a result of human-caused greenhouse gas emissions has been taken up by the ocean?
93%
When winds blow over the surface ocean to cause evaporative cooling, what happens to the heat that leaves the ocean surface?
it is transferred from the ocean to the atmosphere as latent heat in the form of atmospheric water vapor
Where is the surface ocean salinity typically highest?
subtropical gyres
The conveyor belt circulation explains, in part, why nitrate and phosphate concentrations in the deep ocean are
low in the deep North Atlantic and high in the deep North Pacific
Oxygen concentration reaches a minimum level just below the sunlit layer (eutrophic zone) of the ocean because
microbial respiration fueled by dead organic material consumes oxygen down to low levels
What is expected to happen to the oxygen minimum zone in response to global warming?
the concentration of oxygen will decline
Carbon dioxide is high in the deep ocean because
microbial consumption of organic matter and associated respiration produces carbon dioxide
In which direction would carbon dioxide diffuse across the air-sea interface if deep water were brought up to the surface and into contact with the atmosphere
CO2 would diffuse out of the ocean
At the current rate of CO2 emissions, how much more acidic will the ocean be relative to pre-industrial levels?
170% increase
What happens to the Walker Circulation Cell in the transition from normal to El Nino conditions?
the Walker Circulation Cell slows down or reverses
What happens to the Cold Tong in the eastern Pacific during El Nino conditions relative to normal condition?
the Cold Tong becomes less cold and shrinks back toward the Peru coast
What happens to the global average temperature during an El Nino year?
rises pretty dramatically
How can the effects of El Nino conditions in the Pacific be transmitted to the far reaches of the globe?
variation in the position of the jet stream in the atmosphere
At current CO2 emission rates, what sort of timelines are we facing before polar seas become corrosive to calcium shells and coral reef growth is slowed or stopped altogether?
in 20-30 years
Are humans now powerful enough to prevent a future ice age from happening?
yes
What is the level of certainty that the observed global warming is largely causes by humans?
95% confidence level
What is the estimated asset value, associated with low-lying megacities around the world, that are vulnerable to a 1 meter sea level rise by the end of this century?
in the tens of trillions of US dollars range
How soon might we see the Arctic Ocean completely ice-free during summer periods?
ice free as soon as 2030
What must happen to global CO2 emission to stay below a 2C warming?
the entire planet has to go to net zero emissions by 2050
On the scale of all the generations that have ever existed on planet earth, is the present generation super special?
yes, this generation is the generation that will decide the fate of humanity
What is the key hurdle in Cornell’s 2035 zero carbon emissions plan?
developing earth-source heating for the campus
