CHAPTER 10: OCEAN ECOSYSTEMS Flashcards
What are costal dead zones?
Coastal waters with too little dissolved oxygen to support most marine life
What human activity has increased coastal dead zones?
Fertilizer runoff from farms
Where are majority of coastal dead zones?
Atlantic shores USA and Atlantic shores Europe
Oceans cover what percentage of earths surface?
71
70% of oxygen comes from what in the oceans?
Marine plants
How much of the world depends on the ocean as a food source?
Nearly half.
What light wavelength penetrates deepest in the ocean?
Blue wavelength
How far does sunlight penetrate the ocean?
Uppermost layers, 250 m
Oceans surface temps vary with…
latitude
What is the transitional zone of temperature decline called?
Thermocline
What affects the thermocline?
Latitude and the ocean depth
Which zone of the ocean is relatively warm and sunlit?
Epipelagic Zone… 200m
Layers of the ocean
Epipelagic Zone Mesoelagic Zone Bathypelagic Zone Abyssopelagic Zone Hadal Zone
(EMBAH)
What is the continental shelf?
shallow, sloping near continental margins
What is Continental slope?
transition b/w self and floor
What is the Abyssal Plains?
lays b/w 4000-6000m depth
What are mid ocean ridges?
submarine mountain systems stretching from pole to pole
What are deep sea trenches
Lowest point of ocean
Salinity is…
Concentration of dissolved minerals in seawater
Main source of salinity in oceans
Rivers… 2.5 billion tonnes per year
What is the average pH of the ocean
8.16, Basic
how much of anthropogenic carbon emissions have been absorbed by the oceans in the last 200 years?
1/3
As CO2 is absorbed by seawater, what forms which makes the seawater more acidic?
Carbonic acid - H2CO3
How much is the pH of the ocean predicted to fall by 2100?
0.4 units, toward acid
What are the 5 factors that form oceanic circulation patterns?
- WINDS
- DENSITY DIFFERENCE IN SEA WATER
- CORIOLIS EFFECT
- SHAPE OF OCEAN BASINS
- ASTRONOMICAL FACTORS
Define Ocean currents
any persistent, dominantly horizontal flow of ocean water
What are ocean currents driven by
wind blowing over the surface, friction
Why are ocean currents essential?
Sustaining global energy balance
13% of total _____ movement from low to high latitudes
HEAT
The ocean temperature structure is…
layered
What are gyres?
Large circular currents
What are gyres produced by?
Wind, Coriolis effect, Land masses
Why are gyres important?
move warm waters toward poles and cold waters toward equator
The east coast tends to be effected by what temperature gyre?
Warm
The west coast tends to be effected by what temperature gyre
cold
Upwelling zones are only located on which side of continents?
WEST
What flourishes in upwelling zones?
Fishing
What is the circumpolar gyre and where is it located?
West winds around Antaractiica
What is thermocline circulation driven by?
Density differences (temp and salinity)
