EARTH 154 Final

What are the advantages of wind energy

- Renewable - No production of polluting gases (CLEAN ENERGY) - Free energy resource -provide/jobs and other economic activity -new habitat for wildlife -set far apart so they can still sail around them -tourism

What are disadvantages of wind energy

-bird and bat death -bird migration affected -ruin yachting and fishing areas -disrupt view and decrease property values -noise & lights

What are the advantages of tidal energy

-clean -inexpensive once set up -renewable -keeps CO2 out of atmosphere -when cost of fuel gets high, we won't need it

point absorber

-floats on surface -connected to seafloor with cables -converts rise and fall of waves into electricity

Disadvantages of Wave Energy

-marine life (organism killed) -leakage of hydraulic fluid -unsightly (NIMBY) -Noisy (above and below) -Shipping routes affected

Problems associated with utilizing tidal power

-marine life killed (fish, mammals caught in blades) -acoustic outputs affect marine organisms (underwater noise) -NIMBY -Corrosion -cause turbidity -problems for trade routes -changes in sediment

Advantages of Wave Energy

-renewable -cheap once installed -desalinate seawater(combat drought) -close to consumers

How can gas hydrates affect the seafloor environment

-where gas hydrates are exposed on the seafloor, they support life on the seafloor by providing energy to chemosynthetic bacteria -if hydrates are destabilized, they could form a landslide which could then form a tsunami

What are three regions where upwelling occurs

1. Equator 2. Western Edges of Continents (Coastal) 3. Antarctic

How much has sea level risen since the last ice age

130 meters

How many tides are there in a day?

2 high and 2 low, one on the side of Earth closest to moon and one furthest from moon

How much has sea level risen over the past 150 years

20 cm, large spike in temp caused this

How much energy for electricity is potentially available from offshore wind in the US compared to current electricity consumption?

4 times more electricity from offshore wind

How much is sea level predicted to rise by 2100

40cm

Convection Cell

A circular pattern of air rising, air sinking, and wind. The air heats, the density decreased and it rises, and then the air cools at high latitude and the density increases and the air sinks again

What is BSR?

A reflection that roughly parallels the seafloor reflection, presumably caused by the contrast between an overlying clathrate (gas hydrate) and underlying gas-saturated sediments or occasionally by opal transition

Caught most in oceans

Anchovy

Salmon Fisheries in Atlantic v Pacific

Atlantic: significantly reduced population, most not wild due to stocking of rivers, Weak population, needs to continue to be restocked Pacific: Alaskan: viable population, fishing controlled, California and Oregon: Reduced population near collapse, very restricted fishing

what technologies have made wind power more economical

Better and lighter materials, lighter weight, stronger, more efficient (corrosion resistance) There are also computer controlled turbines that can regulate pitch and direction.

Coral and Coral Reefs with temperatures rising

Bleached due to symbiotic algae leaving, become stressed and will most likely die

What is going on in Rhode Island with offshore wind

Block Island -first offshore wind farm in the US -very small 5 turbines -17,000 homes (30MW)

Neg affects by humans on reefs

Breakage due to direct contact, overfishing, pollution, changes in behavior from feeding/harassment

Two countries that catch the most fish

CHINA, second could be: Peru, India/ Indonesia

What is the acid that is causing the acidification of the oceans

CO2, as it increases in atmosphere it also increases in water and causes acid

With the release of methane what could happen in the seafloor when pressure is decreased (destabilization)

Can cause slope destabilization and could form a landslide. A large landslide could trigger a tsunami

Coriolis Effect

Causes moving air and water to turn left in the southern hemisphere and turn right in the northern hemisphere due to Earth's surface velocity to decrease towards poles.

Where do gas hydrates occur

Continental Margins (passive and active) (shelf and slope) and Arctic Permafrost

CITES

Convention on International Trade in Endangered Species, they are trying to add shark species to the endangered list

Coral Polyp, how is algae important, what are coral skeletons, and how do these relate to the reef

Coral polyp are tiny soft bodied organisms that have symbiotic algae inside of them. They secrete a skeleton on their base and they live and reproduce on the outside of the skeleton. These make up a coral reef

What projects are underway involving gas hydrate extraction and production

Different countries are investigating extraction techniques, countries include Japanese, Canadians, Germans, India, and US Projects in the Gulf and the Arctic trying to extract the gas hydrates and figure out how to commercially extract

How can pollution and disease be problems with aquaculture

Diseases will begin in a pen and be contained and spread to all of the fish in the unit

Why is there so much plastic in the oceans

Doesn't biodegrade just continues to break down into smaller pieces

Overtopping Devices

Elevate a reservoir and as water enters the reservoir there are turbines that harness the waves potential energy

Four things we can do to stop overfishing

End Gov Subsidies, farm herbivorous fish, register vessels, create rules and regulations and enforce them, establish no take zones

Europe vs US in wave and tidal Energy

Europe has much more already and planned than US, for they are committed to reducing CO2 outputs.

European countries with significant offshore wind projects

Germany, UK, Denmark, Netherlands

Where do coral grow what type of water do they need

Grow in tropics, clear, shallow water, with a constant warm temperature, for they are very sensitive

What is overfishing?

Harvesting so many fish of a species, especially immature fish, that not enough breeding stock is left to replenish the species and it becomes unprofitable to harvest them. -commercial depletion-extinction

Where does the US have a wave energy test site

Hawaii

What techniques are used to catch bluefin tuna

Helicopters find fish, small boats come off main boat and catch with purse sienes

Air goes from high pressure to low pressure... i.e

High latitude to low latitude

Sustainable fishing

Hook and line, harpooning, traps

Dead Zone

In a body of water, an area with extremely low oxygen concentration and very little life

Tidal Energy Projects in South Korea

Incheon Bay and Sihwa Lake

ICCAT

International Commission for the Conservation of Atlantic Tunas, has no authority

Antarctic Upwelling

Intersection of polar easterlies, westerlies (coriolis effect and Ekman Transport) Surface currents diverge and upwelling caused by wind-driven ocean circulation

arctic ice melting affect sea level

It doesnt affect sea level, like ice cubes in a glass

Whats the net direction of water movement relative to the wind direction?

It moves at 90 degrees to the wind movement to the right in North, to the left in South

What are trends in energy from wind over the last 20 years

It slowly began to increase and then rose dramatically, exponential increase

oceanic gyre

Large system of circular ocean currents formed by global wind patterns and forces created by Earth's rotation

Ocean acidification affect on resources

Less dense skeletons, coral bleaching, shellfish and coral more fragile and smaller, oyster reproduction harmed, some organisms dissolving

How are gas hydrates formed?

Methane forms by the breakdown of organic matter in sediment, biogenic reactions break this down

Tidal energy

More advanced than Wave energy Some proven existing technology and installations: Korea:Lake Sihwa, Tidal barrage, lagoon, biggest in the world More under construction, Incheon Bay Tidal barrages: Canada, France Underwater Turbines, Pentland Firth Scotland, project expanding Technology still developing

Status of Reefs

Most are in danger

Bluefin Tuna population status

Mostly overfished in Japan and used for sushi, only 15-20 % left

NIMBY

Not In My Backyard attitude. People don't want things like landfills to be put where they live.

What is a problem with moving to deeper water

Not as much nutrients available due to lack of light

What are planned US offshore wind projects? Why here?

On the East Coast, there is a lot of wind here and a lot of consumers very close to the production site. Northeast US -Vineyard Wind Project (South Cape Cod) -Deepwater Wind built Block Island (Rhode Island)

Palau

Opened the first shark sanctuary and generate income from shark tourism

What three factors are needed to form gas hydrates

Organic carbon rich sediment, high pressure, low temperature

What is bycatch

Organisms unintentionally killed during the harvesting of a different, desirable species

5 ways salmon are under threat

Overfishing, require clean rivers, dams obstruct rivers, population modified by stocking, global warming

Types of devices needed for generating wave energy

Point Absorber (heave buoy, submerged pressure differential, oscillating wind surge), Attenuator, Overtopping Device, Terminator

trade winds

Prevailing winds that blow from 30 degrees north latitude to the equator and that blow from 30 degrees south latitude to the equator and curve to the west

Severn Estuary Tidal Barrage

Proposed barrage in the UK, it would have 1,026 turbines, it would produce 6.5 GW and give 5% of UK's electricity needs -did not happen bc it would affect marine life, shipping, but it was eventually rejected by UK Gov

Unsustainable Fishing Techniques

Purse sienes, gillnets, longline, trawling, dredging

Tuna Farming

Removes young fish from the water before they can reproduce and fattens up wild tuna before eating

Equatorial Upwelling

SE trades cross equator, the coriolis effect and Ekman transport cause divergence and water can upwell at the equator

What needs to be done to save the Tuna population

Set quotas and enforce them, and have international agreements

What are sharks mainly caught for

Shark fin soup, fins are cut off the rest is thrown back into water

Largest tidal power installation

Sihwa Lake in Korea

Sharks and overfishing by humans

Some are at risk of extinction but not all

Wave energy

Still in testing and development stage A few active projects exist (e.g., Australia)

wind energy

Technology well developed on land and offshore Many large offshore installations online Expanding industry Just starting offshore in the US: Block Island = first Planned:Vineyard Wind, Long Island

greenhouse effect

The Earth's surface warms up, and the long wavelength radiation emitted from the Earth's surface is absorbed by green house gases and the Earth's atmosphere heats up

What water is rich in nutrients

The cold deep water

Trend in climate change

The earth has cooled over the last 50-60 years, there has been a decrease in CO2 and temp decreased

Upwelling

The movement of deep, cold, and nutrient-rich water to the surface

Fishing down the food web

The process whereby fisheries in a given ecosystem, having depleted the large predatory fish on top of the food web, turn to increasingly smaller species, finally ending up with previously spurned small fish and invertebrates, everything is out of balance

How much carbon is stored in gas hydrates

There is more carbon stored in these than in oil, gas, and coal combined

What is the status as gas hydrates as an energy source

They are comparable to fossil fuels, but we do not have the technology to extract it on a commercial scale -Methane is the most abundant -also a lot of carbon in these

Decreasing ph affect animals that make a shell/skeleton

They have less carbonate ions available to make their skeletons, so they form weaker CaCO3 shells

What is problem with salmon on fish farms escaping into rivers

Threaten gene pool, genetic hybrids with interbreeding and different genetic makeup of salmon

Ways of generating electricity from tides

Tidal Barrage Tidal Lagoon Underwater Turbines (Tidal Stream Generator)

Coral as a resource

Tourism, fishing, biodiversity, protect shorelines

where is the biggest dead zone

US Gulf Coast

Where does US rank globally off-shore wind energy, who are world leaders

US is not ranked for offshore wind energy, leaders include Denmark and Germany

Incheon Bay

Under construction tidal barrages in South Korea

What characterizes the Earths climate over the last 2 million years? What causes these cycles?

Variations in the Earth's orbit causes these cycles, they affect the amount of sun energy that reaches earth. Glacial-Interglacial period, we are currently in an interglacial period

What is storm surge and how is it related to a hurricane

Water is piled up on coast by the storm and winds, destructive to coast

Relative status of electricity generation of wave vs tidal vs wind

Wave energy is very experimental, not many developments. Tidal energy has more development than waves, but not as much as offshore wind. Tidal energy is also local. Wind Energy is developed and is already planned.

How do gas hydrates support chemosynthetic bacteria

When exposed on the seafloor, The oxidation of methane provides energy to chemosynthetic bacteria which is the base of the food chain at these areas.

What is the Cape Wind project and what happened to it?

Wind farm off Nantucket's coast, bogged down by Gov regulations

How might gas hydrates affect climate change

With the destabilization of gas hydrates, methane can be released into the atmosphere, methane is a greenhouse gas, and the release of it into the environment could increase warming (affect climate)

What is el nino

a breakdown in trade wind driven upwelling, occurs every 3-8 years

Tidal Barrage

a dam across the mouth of estuaries, it has channels with turbines so when the tide comes in, the generator turns one way, then as the tide goes down, the generator turns the other way. The tide moves the turbine and generator to make electricity.

how much energy can we get from tidal power on a global scale? What does this say about tidal power?

a few percent of global power consumption, this is important on a local or regional scale, it will not fix all of the world's energy problems

How much fish in the US comes from aquaculture

about half

How much of sea level rise is due to warming rather than melting

about half

Tidal Lagoon

an artificial enclosure with a small opening that focuses the tide in one spot, here there are turbines that collect energy

Plastic problems in the ocean

animals consume, can poison animals, invasive species attached to plastic, toxins passed up the food chain

How does el nino affect ocean resources

bad fishing off the coast of Peru, anchovey's are important and they are unable to fish because of this

Salmon lifecycle different than other fish

born in rivers, go to sea, go back to rivers to reproduce

BSR

bottom simulating reflector

What makes a hurricane die out

cold water or land

Life at gas hydrates

crabs, clams, mussels, chemosynthetic bacteria, shrimp, tubeworms

Farmed fish escaping

create competition for food, shelter, and spouses

What are gas hydrates?

crystalline solid ice-like compounds. Within these structures are small gas molecules trapped inside of a cage of water molecules

What is the main organic matter to form gas hydrates

dead phytoplankton

How much energy could we get from waves globally?

double the current world electricity production

How much energy could we get from tides globally

few percent of global electricity potentially

Underwater Turbines

fields of turbines that are underwater that

How do Dead Zones affect ocean resources?

food base reduced, habitat lost or damaged, migratory patterns disrupted, biodiversity reduced

What led to overfishing

freezing fish increase in demand and could sell overseas, larger trawlers were invented and they would stay at sea longer due to being able to freeze the fish

What causes dead zone

freshwater discharge cut off salt water from air, eutrophication begins, decomposition of biomass on the ocean floor begins, depletion of O2

What and where is the pacific garbage patch, why does the trash accumulate here

gyre of trash located in the Central North Pacific between CA and HA, the ocean gyre here keeps the trash in circulation

Where are gas hydrates stable

high pressure and low temperature

Sihwa Lake Tidal Power

in South Korea, Tidal Lagoon/Barrage, world's largest tidal power installation

How are hurricanes affected by global warming

increase intensity due to warmer waters creating stronger storms

Attenuator

long floating unit that uses wave oscillation to pressurize fluids to make energy, large fields of these

What drives a hurricane? How do hurricanes work? (What are wind patterns)?

low pressure storm that blows towards the center, curve and spiral due to correollis affect bending winds to the right, driven by evaporation of warm water

aquaculture affecting coasts

mangroves destroyed, pollute habitats due to waste and chemicals dumping

How are temp histories of the ocean determined

measurement of the oxygen isotope ratio in composition of marine limestone

What gas is there a lot of in gas hydrates

methane

Estuaries

mouths of rivers at the ocean, mixing zone between fresh and salt water; influenced by tides

Dynamic Tidal Power, why will it not happen?

not yet attempted - Long dams built from coasts straight out into the sea, it will harness oscillating coastal tidal currents -on such a large scale, it is just a concept

How did Gov contribute to overfishing

offered subsidies to continue exploring fishing and create larger ships

Climate change rate and affect on organisms

organisms can adjust gradually, but if this rate increases too much they will not be able to adapt quick enough

COD in the US and Canada

populations collapsed and so did the fishing industry, in 1992, first to collapse

Tidal Lagoon in Swansea

proposed, but this was also rejected by UK Gov

trends in global temp and sea level last 20,000 years

sea levels risen and global temp rise, this happened due to transition from glacial to interglacial period

Inland dams affect on rivers and the coast

sediment is stuck at dams and doesn't contribute to coast, so the sediment at the coast begins to compact and sink down.

Scottland Tidal Project in Pentland Firth

started as a test, but now in Northern Scotland (Pentland Firth) there are plans to have a field of underwater turbines. This project is proceeding -269 Turbines -398 Megawatts -Power 175,000 homes

tradgedy of the commons

the notion that any resource thats open to everyone, like air, or part of the ocean will eventually be destroyed because everyone can use it, but no one is held responsible for preserving it (shared resource that could benefit everyone is destroyed)

US goals for alternate energy in the next 20 years

there could be 20% from offshore energy in the next 20 years. there will be a growth in offshore wind

How does ocean warming affect sealevel

thermal expansion contributes to sea level rise

Wild fish role in fish farming

they serve as food for farmed fish

Organisms that cant move and ocean warming

they will likely die

Why is upwelling important?

to ocean life, brings much nutrients to the surface, areas are often habitats for enormous schools of fish

With the oceans warming, where do organisms go in terms of Latitude and water depth

towards the poles and to deeper water (both are colder)

Coastal Upwelling

trade winds blow the surface water offshore at relatively low latitude

What type of fishing damage seafloor

trawling and dredging

What drives the circulation of the atmosphere

variable heating by the sun drives the circulation of the atmosphere

How can gas hydrates be destabilized

warming of the oceans/ global warming (temperature increases) sea-level lowering (pressure decreases)

Terminators

waves flow into a chamber, the waves move the water level inside the chamber up and down which moves air pressure back and fourth to drive a turbine to generate energy.

What affects surface currents?

wind

What is needed for wind energy

wind, turbines, connection to electricity grid, wind farm close to consumers (energy storage)