Oceans 2

Capillary Waves

Small waves with surface tension acting as restoring force.

Wind Waves (Gravity Waves)

Generated by wind; gravity is restoring force.

Swell Waves

Long period, organized waves generated by distant winds; can travel thousands of miles with little change.

Constructive Waves

Waves with similar period and wavelength that combine to form larger waves.

Internal Waves

Waves that propagate within the water column, not on the surface.

Surf Waves

Waves transformed near the shore, characterized by breaking and energy release on the shoreline.

Wind Strength

Must exceed wave crest speed to transfer energy efficiently.

Wind Duration

Longer blowing winds generate larger waves.

Fetch

The uninterrupted distance over which wind blows; longer fetch produces larger waves.

Local Winds

Produce short-period, choppy, and disorganized waves (sea).

Fully Developed Sea

Equilibrium where wave energy input from wind equals energy loss through breaking; waves stop growing.

Wavelength

Horizontal distance between successive wave crests.

Period

Time between successive crests.

Wave Height

Vertical distance between crest and trough.

Amplitude

Half the wave height.

Wave Speed (Celerity)

Speed at which wave energy propagates.

Wave Steepness

Ratio of wave height to wavelength; relates to wave breaking potential.

Wave Base

Depth below which orbital motion is negligible.

Shoaling

As waves approach shore, they interact with the seabed, causing a decrease in wave speed, decrease in wavelength, increase in wave height and steepness.

Refraction

Bending of wave crests as they enter shallow water at an angle.

Wave Breaking

Occurs when wave steepness reaches critical value; energy dissipated in surf zone.

Tropical Cyclone

A warm-core, low-pressure weather system over tropical or subtropical waters with organized circular wind patterns.

Eye

Calm center with descending dry air and clear skies.

Eye Wall

Surrounds eye; area of strongest winds and intense thunderstorms.

Rainbands

Spiral bands producing heavy rain and possible tornadoes.

Category 1 Hurricane

74-95 mph (119-153 km/h) with some damage, dangerous winds.

Category 5 Hurricane

≥157 mph (≥252 km/h) with catastrophic damage.

What leads to ocean acidification?

Higher CO2 and lower pH.

What percentage of anthropogenic carbon is absorbed by the ocean?

30%.

What determines the exchange of gases between the atmosphere and oceans?

Saturation solubility and concentration of gas in water.

What happens if water is undersaturated with gas?

Gas is transferred into the water.

What increases the solubility of gases in water?

Increasing pressure and decreasing temperature.

How does warming ocean temperature affect oxygen levels?

It holds less oxygen.

How does salinity affect gas solubility in water?

Salty seawater decreases solubility relative to freshwater.

Where is more O2 and CO2 found, oceans or atmosphere?

In the oceans.

What are carbon sources in the ocean?

Areas that experience upwelling.

What happens to oxygen concentration with depth in the ocean?

It changes and is not a conservative property.

What occurs in the photic zone of the ocean?

CO2 is consumed and oxygen is produced during photosynthesis.

What is the oxygen minimum zone?

An area too far from the surface for atmospheric exchange with not enough light for photosynthesis.

What is the percentage decline in measured oxygen in global oceans?

2%.

What causes a reduction in oxygen levels in oceans?

Warm water holds less dissolved oxygen than cold water.

What is one effect of increased stratification in oceans?

Slowed sinking of oxygen-rich cold water into deep oceans.

What does increased primary productivity at the surface lead to?

More organic material sinking and decomposing.

What is the reaction for CO2 dissolution in water?

CO2 + H2O ↔ H2CO3.

What happens as more H+ is added to seawater?

It leads to more bicarbonate and carbonic acid.

What are cocolithophores, terrapods, and forams?

They make up biogenic sediment.

What do water waves represent?

Propagation of energy.

What is the wave period?

The number of seconds it takes for two waves to pass by a single point.

What are wind waves?

Waves with periods between 1/10th of a second to 20 seconds.

What produces tides?

Gravitational forces of the sun and the moon.

What is wave celerity?

Distance divided by time.

What happens to waves as they propagate from deep to shallow water?

They undergo shoaling.

What is wave refraction?

Bending of the wave crest as it enters shallow water.

What occurs when waves approach the shoreline?

Waves slow, height increases, and they break.

What is the disturbing force of a wave?

Wind.

What is the restoring force for capillary waves?

Surface tension.

If the high tide of a diurnal tide occurs at 10:00 A.M., when will the next high tide occur?

Approximately at 10:50 AM the next day

What is the process of a wave crest bending as it moves into shallow water called?

Refraction

What happens to wave speed as a wave moves into intermediate-shallow water?

Wave speed decreases

What is the tide generating force of the Sun compared to the Moon?

About 50% as large

What is a Tropical Cyclone?

A warm-core low-pressure system that develops over tropical or subtropical waters

What are the characteristics of the eye of a tropical cyclone?

Dry descending air, calmer winds, little overhead cloud cover

What occurs in the eye wall of a tropical cyclone?

Warm air rises violently and the strongest winds are located immediately outside

What is storm surge?

Rise of sea level produced by water being pushed towards the shore by storm winds

What factors influence storm surge?

Intensity, size, forward speed, angle of approach, width and slope of shelf

What is the difference between eustatic and local sea level changes?

Eustatic affects all coastlines; local changes can vary due to vertical land motion

What are the main drivers of eustatic sea level changes?

Changes in ice sheet volume, melting water, and thermal expansion

How much has global average sea level risen since 1880?

8-9 inches (21-24 centimeters)

What is the current rate of global sea level rise?

0.14 inches (3.6 millimeters) per year from 2006-2015

What are the causes of Ice Ages?

Eccentricity, obliquity, precession

What is the significance of the Saffir-Simpson Scale?

It measures tropical cyclone strength based on max sustained wind speed

What is the impact of sea level rise on coastal cities?

Threatens infrastructure, economies, and safety of coastal populations

What are the conditions necessary for cyclone formation?

Tropical wave, enhanced humidity, conditional instability, warm sea surface temperature, no vertical wind shear

Why do the highest number of storms occur in early September?

Seasonal climatic conditions favor storm development

What is a storm tide?

A combination of storm surge and astronomical tide

What is the relationship between full moon, high tide, and flooding?

They create spring tides with amplified tidal ranges