Oceanography Week 7
1. Percent of human-caused warming adsorbed by oceans: 93% = melting snow and ice
7% = warming land surface and atmosphere
2. How much is mean global ocean temperatures predicted to increase by
2100: Additional 1 to 4 degrees
3. 5 ways the oceans are changing: 1. Rising sea level
2. Melting sea ice
3. Ice shelves and glaciers are destabilizing
4. Marine biochemistry
5. Ocean circulation
4. What is meant by the phrase "the oceans have buffered temperature and
greenhouse gas levels".: The oceans moderate earth temperature
5. What do models suggest will happen to ocean circulation (why do they think
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, MOC will slow down?): Warming will slow ocean circulation (evidence from changes in the structure of
temperature, salinity, and chlorofluorocarbons).
6. What are polynyas and why are they important?: Winds off the Antarctic ice sheets push sea
ice away from the coast to form ice-free areas called polynyas. Exposed to the atmosphere (colder than ocean) surface
waters in polynyas are chilled and more saline (denser). Cold, dense waters cascade down the continental slope to the
seafloor to form a water mass called Antarctic Bottom Water (AABW).
7. How is meltwater from the Greenland Ice Sheet related to what happens with
MOC (meridional overturning circulation)?: Increasing meltwater flows off the Greenland Ice
Sheet have caused freshening in the North Atlantic surface waters, which may be weakening the MOC. Convection
and deepwater formation slow, as does the MOC.
8. What is Isopycnal heave and what does it do?: With less cold deepwater forming and filling
the abyssal ocean, warmer water higher in the water column sinks to fill the space. Isopycnal heave communicates this
heat to the deep ocean by producing less ABW as opposed to producing warmer ABW (deep-ocean changes).
9. What are the implications of slowing ocean circulation?: Global warming slows ocean
circulation which reduces the role that the ocean can play in helping the earth deal with climate change.
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1. Percent of human-caused warming adsorbed by oceans: 93% = melting snow and ice
7% = warming land surface and atmosphere
2. How much is mean global ocean temperatures predicted to increase by
2100: Additional 1 to 4 degrees
3. 5 ways the oceans are changing: 1. Rising sea level
2. Melting sea ice
3. Ice shelves and glaciers are destabilizing
4. Marine biochemistry
5. Ocean circulation
4. What is meant by the phrase "the oceans have buffered temperature and
greenhouse gas levels".: The oceans moderate earth temperature
5. What do models suggest will happen to ocean circulation (why do they think
1/4
, MOC will slow down?): Warming will slow ocean circulation (evidence from changes in the structure of
temperature, salinity, and chlorofluorocarbons).
6. What are polynyas and why are they important?: Winds off the Antarctic ice sheets push sea
ice away from the coast to form ice-free areas called polynyas. Exposed to the atmosphere (colder than ocean) surface
waters in polynyas are chilled and more saline (denser). Cold, dense waters cascade down the continental slope to the
seafloor to form a water mass called Antarctic Bottom Water (AABW).
7. How is meltwater from the Greenland Ice Sheet related to what happens with
MOC (meridional overturning circulation)?: Increasing meltwater flows off the Greenland Ice
Sheet have caused freshening in the North Atlantic surface waters, which may be weakening the MOC. Convection
and deepwater formation slow, as does the MOC.
8. What is Isopycnal heave and what does it do?: With less cold deepwater forming and filling
the abyssal ocean, warmer water higher in the water column sinks to fill the space. Isopycnal heave communicates this
heat to the deep ocean by producing less ABW as opposed to producing warmer ABW (deep-ocean changes).
9. What are the implications of slowing ocean circulation?: Global warming slows ocean
circulation which reduces the role that the ocean can play in helping the earth deal with climate change.
2/4
