Stratification

Question 1

What mathematical concept is used to describe stratification?

Answer 1

Stratification is described mathematically through density differences (∆ρ = ρ1 - ρ2).

Question 2

What happens when stratification increases?

Answer 2

adds stability to water column.

Question 3

What does stable mass distribution do in a stratified ocean?

Answer 3

resists vertical motion.

Question 4

What is Brunt-Väisälä frequency (N) used for?

Answer 4

N quantifies stratification by measuring natural oscillation resulting from vertical displacement.

Question 5

What indicates strong stratification according to Brunt-Väisälä frequency?

Answer 5

A large N indicates strong stratification and high stability.

Question 6

What occurs during the mixing process in the ocean?

Answer 6

Mixing raises center of mass of water column and converts kinetic energy into potential energy.

Question 7

What are the main layers mentioned in the ocean’s vertical structure?

Answer 7

The main layers are the thermocline, halocline, pycnocline, and mixed layer.

Question 8

What is the importance of the surface mixed layer?

Answer 8

crucial for air-sea exchange and tropical cyclone development.

Question 9

What characterizes the typical vertical structure of the open ocean?

Answer 9

It features a warmer, lighter upper mixed layer and a cooler, heavier lower stratified layer.

Question 10

What can stratification block from mixing?

Answer 10

gases, nutrients, and heat between surface layer and deep ocean.

Question 11

How does solar heating affect stratification?

Answer 11

Increased solar radiation reduces surface density, leading to increased stratification.

Question 12

What seasonal changes impact mixed layer depth?

Answer 12

Winter leads to maximum mixed layer depth due to wind stirring and cooling, while summer results in thinner mixed layers.

Question 13

What does the density anomaly in mixed layer depth refer to?

Answer 13

It refers to long-term averages of density differences in the mixed layer.

Question 14

What role does wind mixing play in the mixed layer?

Answer 14

deepens mixed layer by entraining fluid from below.

Question 15

How does buoyancy loss due to cooling/evaporation affect the mixed layer?

Answer 15

causes dense water at the surface to become unstable, leading to mixing.

Question 16

What happens when buoyancy gain from heating/precipitation occurs in the mixed layer?

Answer 16

stabilizes surface water, can make the mixed layer shallower.

Question 17

Why does mixing create a stair-step pattern in density and temperature profiles?

Answer 17

Multiple episodes of heating, cooling, and mixing contribute

Question 18

What is an effect of tropical cyclones on the mixed layer?

Answer 18

significant storm-driven mixing, which deepens the pycnocline.

Question 19

How can long-term seasonal stratification affect biological production?

Answer 19

Seasonal stratification controls biological production cycle due to impact on temperature and density gradients.

Question 20

What happens to the mixed layer at the end of winter?

Answer 20

deepens to maximum thickness due to erosion of stratification.

Question 21

What are the characteristics of an unstable density distribution?

Answer 21

vertical motion within water column.

Question 22

What is a key characteristic of the neutral state in stratification?

Answer 22

density has no influence on vertical motion.

Question 23

How is the mixed layer affected by diurnal heating?

Answer 23

Diurnal heating can lead to variability in mixed layer depth due to the difference between daytime heating and nighttime cooling.

Question 24

What is the effect of storm timing on mixing efficiency?

Answer 24

The timing of storms, especially in seasonally stratified shelves, can affect the efficiency of storm-driven mixing.

Question 25

How is density difference quantified in ocean studies?

Answer 25

Density difference is quantified using the equation ∆ρ = ρ1 - ρ2, which describes layers.

Question 26

What is indicated by a small Brunt-Väisälä frequency (N)?

Answer 26

A small N indicates weak stability and a small vertical density difference.

Question 27

What physical process is involved in vertical motion within stratified layers?

Answer 27

The distribution of density within the layers causes vertical motion.

Question 28

How does mixing in the mixed layer affect maximum chlorophyll levels?

Answer 28

by affecting nutrient availability and primary productivity.

Question 29

What seasonal phenomenon leads to the creation of the thermocline?

Answer 29

The seasonal warming of surface layers creates a temperature gradient that forms the thermocline.

Question 30

What is the significance of the nutricline in stratification?

Answer 30

The nutricline marks a region of rapid change in nutrient concentrations, which can be crucial for marine productivity.

Question 31

How does seasonal evolution affect the mixed layer?

Answer 31

Seasonal evolution impacts growth and decay of thermocline, affecting depth of mixed layer.

Question 32

What is the outcome of increased solar heating on water density stratification?

Answer 32

Increased solar heating results in reduced density at the surface, enhancing stratification.

Question 33

What do measurements of mixed layer depths often rely on?

Answer 33

temperature and density thresholds to define mixed layer properties.

Question 34

What is an example of a local factor impacting solar-driven stratification?

Answer 34

Local time variations can significantly affect spatial gradients of solar heating and stratification.

Question 35

What does the term ‘pycnocline’ refer to in ocean stratification?

Answer 35

a layer in the ocean where there is a rapid change in density with depth.

Question 36

How does the concept of kinetic energy relate to mixing in water columns?

Answer 36

Kinetic energy from mixing is converted into potential energy, facilitating the lifting of mass against gravity.

Question 37

What factors can influence the spatial footprint of river plumes?

Answer 37

Wind, river discharge, and initial shelf water conditions

Question 38

What does the mixed layer allow for in terms of bio-chemistry?

Answer 38

facilitates crucial processes for gas exchange and presence of photosynthesizers.

Question 39

What conditions characterize neutral stratification?

Answer 39

implies that density neither resists nor promotes vertical motion.

Question 40

How does the concept of stratification intersect with global climate?

Answer 40

Stratification is significant in the ocean as it affects gas and heat exchange, influencing global climate systems.

Question 41

What role does the atmosphere play in stratification dynamics?

Answer 41

surface layer’s contact with atmosphere facilitates gas and heat exchange crucial for stratification dynamics.