Ocean 100 Exam 3

What is the Greenhouse effect?

Solar energy goes into the earth and bounces off the ground and reradiates and bounces back to the atmosphere but it gets stuck causing the infrared radiation to get trapped within Earth

What are the greenhouse gases?

H20, C02, Ch4, N20, 03

What’s the concentration of CO2 in the atm today?

0.04%

What do the Temp and CO2 records indicate?

That temperature has fluctuated over the Earth’s lifetime, in fact, the Earth is the coldest it has been in the last 300 million years, 390 million years ago there was a LOT of CO2 compared to now

What are specific reasons for an increase in greenhouse gas emissions?

Fossil fuels, industry and manufacturing cement, land use (deforestation, urbanization, soil erosion), cattle, commerce ships moving in the ocean

What does anthropogenic mean?

Human-made

How has the atmosphere changed over geologic time?

390 million years ago there was a LOT of CO2, decreases after the evolution of plants with the creation of oxygen due to photosynthesis, once the industrial revolution causes a slight increase in CO2

What is going on with polar ice, especially in the Arctic?

Polar ice in Arctic is melting which is slowly heating up the Arctic Sea

What’s sea ice?

Sea water turning into ice

What are some changes with increased energy in the environment?

Ice is melting in the Arctic, warmer climate overall (compared to more recent times, its overall cooler compared to the bigger picture), these changes cause rising sea level

Where are the changes in increased energy in the environment mostly seen?

These changes are mostly seen in the Northern Hemisphere 

What are the basic conclusions from these charts about the last 500 million years in regards to climate?

The last 500 million years has been hot and only cooling down in very recent times, in fact generally the coldest it has been as we are still leaving the ice age

What trends has CO2 given us over geologic time?

Warmer climate

What are the 2 great buffers against severe climate changes today?

Antarctic ice sheet and the Ocean

How does the Antarctic ice sheet work as a buffer?

Acts as a refrigerator of the world

How does the ocean work as a buffer?

High heat capacity absorbs heat

 What can the Atlantic Overturning Circulation do in future if it’s disrupted by fresh melt waters from Greenland?

It can slow down or stop completely causing another ice age

Why can the Atlantic Overturning Circulation disrupted by fresh water cause another ice age?

Ice melting as freshwater cannot sink leading to the deep current to potentially shut down

In the Atlantic Overturning Circulation is the seawater sinking as fast as it used to?

No, its slowing down

What’s the ocean’s ability to absorb excess anthropogenic heat?... why?

The ocean can absorb heat as it has a high heat capacity, it absorbs over 90% of anthropological heat 

What are icebergs?

Freshwater/chunks of ice from land

Why did the Titanic sink?

It sunk because normally boats can float because they have air inside (less dense than water) however, once there was a hole in the boat, water entered it making it more dense than the water causing it to sink

What’s ocean acidification?

Ocean is absorbing CO2 which is making it more acidic and reduces pH

 How is ocean acidification related to global warming?

Increased CO2 in the atmosphere gets absorbed by the ocean causing the ocean to turn more acidic over time

How are organisms affected by ocean acidification?

Organisms are affected as pH decreases from CO2 being absorbed, ecosystems are threatened as CO2 is new for them

The characteristics of all waves?

Wavelength, height, wave base, still water level, wave base, depth, wave height, wave period

What are waves?

Energy through motion, the water doesn’t move

What happens at promontory?

Headline jets out into ocean, erodes fast, more force from waves as its the first part that is hit by waves

What happens at bay?

Refraction occurs, more gentle waves, slowly gets straightened because waves aren’t hitting it directly and the erosion from promontories gets pushed into bays causing them to get closed off or “filled in”

The life story of deep-water waves

The sea and fetch, the swell, the breakers

What is the Sea?

Area where waves originates by winds

What is the Fetch

Actual formation of the deep water wave

What is the Swell?

Long crested waves trains, travel out of sea

What is the breaker?

Shorelines deliver energy from wind, breaks onto shoreline 

When does a wave break?

 Wave depth=½ length→wave feels bottom, as length decreases, height increases, velocity decreases, steepness increases

What are the two types of breakers?

Spilling breaker and Plunging breaker

What is a spilling breaker?

Gentle slope, spills onto beach

What is a plunging breaker?

 Steep slope, tunnel collapse

What continental feature cause huge waves form (think of the biggest waved surf)?

Submarine canyons

Where do we see these huge waves form?

Portugal and La Jolla

What are shallow water waves?

Waves travel at surface, they drag on the bottom of the ocean, their depth is <1/20 wavelength (huge wave-length)

What are shallow water waves caused by?

Subduction zones & storm surges

Where do you see shallow water waves?

Only near the coast, NOT in ocean

The great tsunami of Japan, 2011 – what’s the magnitude of this quake?

M=9

Why did so many people die in the Japanese tsunami in 2011?

Flat land made it easy for the tsunami to travel

Where did all the debris from the Japan tsunami in 2011 go?

Went to Canada & West Coast of US

The great tsunami of Sumatra, 2004 – earthquake magnitude?

M=9.2

Why were so many people killed in the Sumatra tsunami in 2004?

Unprepared & flat land made it easy for the tsunami to travel across land

How are shallow water waves (in regards to tides) form?

Gravitational pull from the Moon, Earth, & Sun

Where are the bulges of high tide?

Aligned with the Moon on both sides

Where do we see very large and interesting tidal waves?

When an ocean and river comes together which causes a tidal bore

What is a Diurnal tide?

 1 high and 1 low tide per day

What is a Semi-Diurnal tide?

2 high and 2 low tides per day

What is a mixed tide?

2 high and 2 low with unequal heights which is due to formation of the coast

What types of tides do we have in California?

Mixed

What is a tidal period?

Amount of time for a wave cycle to complete

What are the Amphidromic tides?

Counterclockwise rotation of tides

How do Amphidromic tides work?

They rotate in a counterclockwise direction around the ocean and bounce off of continents, similar to wine being swished around in a glass

How does the Coriolis Effect affect tides?

Causes tides to veer off to the right causing it to move in a circular like motion

What exactly are the Amphidromic points?

Where no tidal variation occurs

How do tides behave closer and far away from these amphidromic points?

Closer to these points there are less tidal variations while further away from these points there is more tidal variation

What is the most abundant greenhouse gas?

Water Vapor

What produces the small waves that you see breaking on the beach daily?

Winds

What happens when a tsunami wave comes ashore?

Their wavelength decreases as their wave height increases