Oceans And Their Composition

Question 1

All oceans are connected but scientists separated them into five main oceans…

Answer 1

1. Pacific Ocean - largest and deepest, bugger than all landmass
2. Atlantic Ocean- half of pacific, 20% of water
3. Indian Ocean - 3rd largest, between Africa and Asia
4. Southern ocean - surround Antarctic and us mostly covered with ice
5. Arctic ocean - smallest and shallowest, covered with ice

Question 2

What is salinity and how does it affect seawater?

Answer 2

Measure of the mass of dissolved solids in a mass of water. Saltwater = avg. 1kg water has 35g of salt

Question 3

What are the zones of oceans?

Answer 3

Surface zone: area of shallow seawater that receives the most sunlight; organisms that perform photosyntheses are located here

Middle zone: revives very little du flight and of it only the blue-green wavelengths

Deep zone: plants that photosynthesize are not found here because sunlight doesn’t reach there

Question 4

What are these zones called?

Answer 4

*From top to bottom

Epipelagic zone
Mesopelagic zone
Bathypelagic zone
Abyssopelagic zone
Hadelpelagic zone (trenches)

Question 5

Composition of water: salinity?

Answer 5

Top 500m of water is saltier in warm water than polar water since it evaporates faster leaving behind salt at surface

Question 6

Composition of water: temperature

Answer 6

Temp. Changes from surface to about 1000m depending if located in polar or tropical regions

Question 7

Composition of oceans: density

Answer 7

Ocean water is layered Ann r cold water is dense and warm water is less dense and remains on the surface

Question 8

What are waves?

Answer 8

Movement of energy through a body of water caused by wind blowing transferring energy

Question 9

What are ocean currents?

Answer 9

Large streams of moving water that flow through the oceans

Question 10

What are ocean gyres?

Answer 10

Earths oceans contain large, looped systems of surface currents called gyres.

Question 11

What are deep currents?

Answer 11

Carry cold water from poles to equator

Question 12

How does the ocean contribute to primary productivity?

Answer 12

Almost half of global photosynthesis occurs in the ocean and is completed by phytoplankton.

Photosynthesis doesn’t occur equally through it the whole ocean.

Question 13

What are surface currents?

Answer 13

Large-scale surface ocean currents are driven by global wind systems that are fueled by energy from the sun. These currents transfer heat from the tropics to the polar regions, influencing local and global climate.

Question 14

What are the characteristics of the euphotic zone?

Answer 14

The part of the ocean where sunlight is able to penetrate the water. Phytoplankton are found in this zone and control the populations and distribution of all other organisms.

Question 15

Some examples of phytoplankton?

Answer 15

Microscopic bacteria, algae, plants

Question 16

What limits phytoplankton?

Answer 16

Have plenty of light in the euphotic zone but are limited by nutrients in the ocean. The warmer water of the euphotic zone often doesn’t mix with the denser, colder water below it. The separation of these 2 layers can restrict the flow of nutrients except in specific areas of upwelling.

Question 17

What is upwelling?

Answer 17

The process in which deep, cold water rises toward the surface.

Question 18

What causes high productivity in the ocean?

Answer 18

Nutrients found at the mouth of the river. Coriollis effect causing upwelling.

Question 19

What conditions affect productivity in the ocean?

Answer 19

High: nutrients found at the mouth of the river. Coriollis effect causing upwelling.

Low: lack of sunlight. Thermocline in open ocean that restrict the nutrient flow.

Question 20

What is thermocline?

Answer 20

A thin layer in the ocean where temperature changes very quickly.