Ocean 100 Exam 3 Questions and Answers
The Coastal region - the parts of the coastal region, starting with the coast all the way to the
offshore (we looked at about 6); What wave energy does to a coastal cliff over time - how?
Rivers and cliff erosion? ; what about southern California sand supply? - -Coast: land
extending inland as far as marine influence is seen (ex. SD at coast)
Offshore: extends from breakers to edge of continental shelf
Beach: shore and nearshore, very active
Berm: dry area at foot of coastal cliff (sand)
Wave-Cut Platform: flat eroded bedrock at beach, eroded by waves
Notch: cave cut into sea cliff by waves
Coastal region: land adjacent to the beach
Coast-line: base of cliff, think of the literal line that connects the bottom of a cliff to the
sand/berm
Wave energy erodes cliff over time and brings sand to the beach/berm (ex. California)
River runoff also bring sands to the beach/berm
-What's the significance of the berm?...The winter time beach vs the summer time beach,
why the differences?... - -It is the sand on beach
In winter there's a narrow berm and rocky beach because wave energy is high
In summer there's a wide berm and sandy beach because wave energy is low
Wave energy functions caused by season
-Longshore currents and longshore drift - why? what about southern CA?... - -Longshore
Drift: drift is net movement of sand grains
Longshore Current: movement of water in a surf zone
Current parallel to coast because waves approach beach at an angle, move sand
CA longshore currents move N to S (towards La Jolla)
-The 2 types of coasts and all characteristics of each (the landscapes formed); How does
this tie in with Plate Tectonics?... where do we find them mostly in NA? - -Depositional
Coast: flat coast, passive margin, subsidence (lowering, below sea level), tons of sediment
deposited, deltas and barrier islands, submerging coast, ex. Louisiana, Texas, South
Carolina, New Jersey, Massachusetts
Erosional Coast: tectonic uplift; cliffs; headlands, sea caves, arches, stacks; marine terraces;
emergent coasts; ex. California, San Diego terraces
-Contrast the Atlantic and Gulf to the Pacific coasts; sea level changes and effect on Atlantic
vs Pacific coasts; what about the Gulf coast? - -Atlantic: passive, no plate boundary occurs,
erosional, ocean doesn't migrate inland, high line
Pacific: active, plate boundary occurs, erosional, ocean doesn't migrate inland, high line
Gulf: below sea level, oceans migrate the farthest in, nothing to stop oceans
, -Global sea level changes: what are the causes? How specifically does each affect sea
levels? What happens if all ice melts on Earth? What areas of the US would be affected
most? - -Causes:
climate change: global warming causes sea level to rise, ice age causes sea level to lower
tectonics: mid-ocean ridges, fast spreading leads to sea level rising, slow spreading leads to
sea level lowering
If all ice on earth melted sea level would rise by 70m, east coasts affected more and would
disappear, in west coast SD would disappear
-How do we change the coastline in an ice age vs global warming (when is the shelf
submerged, for instance?); People build houses right on the berm - how? what happens
during storms?... - -Coastline in ice age: shelf not submerged, low sea level
Coastline in global warming: shelf submerged, high sea level from ice melting
Houses built on berm but erosion happens during storms and houses destroyed
-What's our coast in San Diego like? Why is this?... What are the tectonics in southern
California?,.. What exactly controls the shape of the coast here?... - -San Diego is an
erosional coast on an active margin
Shape is controlled by the transform plate boundary Rose Canyon fault which drives local
uplift and shapes the coast (lifting La Jolla)
La jolla used to be a wave cut platform 125,000 yrs ago, now is a nestor terrace and
promontory
-Coastal erosion: what is this? how and why are our coasts and beaches eroding here in
San Diego county, particularly?... what have we done about it?... - -The wearing of land and
the removal of beach or dune sediments by wave action, tidal currents, wave currents,
drainage or high winds
Caused by El Nino and climate change
Built seawalls in an attempt to prevent it- Starves the berms
-Coastal stabilization - Seawalls: why are they built and do they work? Why/why not?
Generally, what can we say of the level of erosion at the beach where a seawall is built?...
What happens to the berm?... - -Sea walls are built to stop erosions and protect home
developments on coast, wave erosion increases at the base of the cliff, the beach/berm is
starved of stand and may disappear
-What is pollution? The 4 types of pollution that enters the oceans: - -Pollution: substances
harmful to marine environment which is introduced by humans
4 types of pollution:
Petroleum, Sewage, Heavy Metals, Solid Waste
-Petroleum, Crude vs refined oil? Oil spills and how they affect wildlife; how did they clean
the beaches? - -Crude Oil: biodegradable, nature can break down into smaller, useful
components
Refined Oil: non-biodegradable, more toxic, ex. plastic and gasoline
The Coastal region - the parts of the coastal region, starting with the coast all the way to the
offshore (we looked at about 6); What wave energy does to a coastal cliff over time - how?
Rivers and cliff erosion? ; what about southern California sand supply? - -Coast: land
extending inland as far as marine influence is seen (ex. SD at coast)
Offshore: extends from breakers to edge of continental shelf
Beach: shore and nearshore, very active
Berm: dry area at foot of coastal cliff (sand)
Wave-Cut Platform: flat eroded bedrock at beach, eroded by waves
Notch: cave cut into sea cliff by waves
Coastal region: land adjacent to the beach
Coast-line: base of cliff, think of the literal line that connects the bottom of a cliff to the
sand/berm
Wave energy erodes cliff over time and brings sand to the beach/berm (ex. California)
River runoff also bring sands to the beach/berm
-What's the significance of the berm?...The winter time beach vs the summer time beach,
why the differences?... - -It is the sand on beach
In winter there's a narrow berm and rocky beach because wave energy is high
In summer there's a wide berm and sandy beach because wave energy is low
Wave energy functions caused by season
-Longshore currents and longshore drift - why? what about southern CA?... - -Longshore
Drift: drift is net movement of sand grains
Longshore Current: movement of water in a surf zone
Current parallel to coast because waves approach beach at an angle, move sand
CA longshore currents move N to S (towards La Jolla)
-The 2 types of coasts and all characteristics of each (the landscapes formed); How does
this tie in with Plate Tectonics?... where do we find them mostly in NA? - -Depositional
Coast: flat coast, passive margin, subsidence (lowering, below sea level), tons of sediment
deposited, deltas and barrier islands, submerging coast, ex. Louisiana, Texas, South
Carolina, New Jersey, Massachusetts
Erosional Coast: tectonic uplift; cliffs; headlands, sea caves, arches, stacks; marine terraces;
emergent coasts; ex. California, San Diego terraces
-Contrast the Atlantic and Gulf to the Pacific coasts; sea level changes and effect on Atlantic
vs Pacific coasts; what about the Gulf coast? - -Atlantic: passive, no plate boundary occurs,
erosional, ocean doesn't migrate inland, high line
Pacific: active, plate boundary occurs, erosional, ocean doesn't migrate inland, high line
Gulf: below sea level, oceans migrate the farthest in, nothing to stop oceans
, -Global sea level changes: what are the causes? How specifically does each affect sea
levels? What happens if all ice melts on Earth? What areas of the US would be affected
most? - -Causes:
climate change: global warming causes sea level to rise, ice age causes sea level to lower
tectonics: mid-ocean ridges, fast spreading leads to sea level rising, slow spreading leads to
sea level lowering
If all ice on earth melted sea level would rise by 70m, east coasts affected more and would
disappear, in west coast SD would disappear
-How do we change the coastline in an ice age vs global warming (when is the shelf
submerged, for instance?); People build houses right on the berm - how? what happens
during storms?... - -Coastline in ice age: shelf not submerged, low sea level
Coastline in global warming: shelf submerged, high sea level from ice melting
Houses built on berm but erosion happens during storms and houses destroyed
-What's our coast in San Diego like? Why is this?... What are the tectonics in southern
California?,.. What exactly controls the shape of the coast here?... - -San Diego is an
erosional coast on an active margin
Shape is controlled by the transform plate boundary Rose Canyon fault which drives local
uplift and shapes the coast (lifting La Jolla)
La jolla used to be a wave cut platform 125,000 yrs ago, now is a nestor terrace and
promontory
-Coastal erosion: what is this? how and why are our coasts and beaches eroding here in
San Diego county, particularly?... what have we done about it?... - -The wearing of land and
the removal of beach or dune sediments by wave action, tidal currents, wave currents,
drainage or high winds
Caused by El Nino and climate change
Built seawalls in an attempt to prevent it- Starves the berms
-Coastal stabilization - Seawalls: why are they built and do they work? Why/why not?
Generally, what can we say of the level of erosion at the beach where a seawall is built?...
What happens to the berm?... - -Sea walls are built to stop erosions and protect home
developments on coast, wave erosion increases at the base of the cliff, the beach/berm is
starved of stand and may disappear
-What is pollution? The 4 types of pollution that enters the oceans: - -Pollution: substances
harmful to marine environment which is introduced by humans
4 types of pollution:
Petroleum, Sewage, Heavy Metals, Solid Waste
-Petroleum, Crude vs refined oil? Oil spills and how they affect wildlife; how did they clean
the beaches? - -Crude Oil: biodegradable, nature can break down into smaller, useful
components
Refined Oil: non-biodegradable, more toxic, ex. plastic and gasoline
