Ocean Formation, Tides and Currents

• The Southern Ocean is located at 60 degrees south latitude.
• The North and South Poles are positioned at 90 degrees latitude.
• The Equator is located at 0 degrees latitude.
• The Prime Meridian is a vertical line at 0 degrees longitude.
• Spring tides occur just after a new or full moon. These tides have the greatest difference between high and low water levels.
• Neap tides have the least difference between high and low tide.
• Volcanic outgassing is theorized to have formed the world's oceans.
• Volcanic eruptions released water vapor, which condensed into clouds as the Earth cooled.
• Theia's impact with Earth resulted in a section of the planet being blown out.
• Rainwater dissolves halite (NaCl) deposits, and runoff carries the dissolved salt into the ocean.
• Ocean currents are flows of ocean water caused by global winds, the Coriolis effect, land placement, gravitational pull, and density differences.
• Surface currents are streams of flowing water in the top 100-400 meters caused by wind.
• The Coriolis effect is the impact of a rotating body on fluids flowing over its surface.
• In the northern hemisphere, the Coriolis effect spins fluids counterclockwise, while in the southern hemisphere, it spins them clockwise.
• The angle of insolation is the angle at which the sun's rays strike Earth's surface.
• A gyre is a rotating current system or massive ocean vortex.
• Thermohaline circulation involves saltier, cold Arctic water sinking due to ice formation, which brings new water to the surface in a continuous rotation.
• GPGP stands for Great Pacific Garbage Patch.
• H2O density = 1.0 g/cm3 = 1000 kg/m3; lower density substances float, while higher density substances sink.
• Average ocean salinity is 35 PPT/PSU.
• Air pressure is the weight of the atmosphere over an area.
• Low pressure results in high precipitation.
• High pressure results in low precipitation and clear skies due to less cloud formation.
• The Equator has high evaporation and precipitation, resulting in average salinity (34-35).
• At 30N and 30S, there is high salinity due to high air pressure and temperature.
• At 60N and 60S, lower salinity occurs due to rising air increasing precipitation and cool temperatures limiting evaporation (salinity = 32-34 ppt).
• At 90N and 90S, very low salinity is due to minimal evaporation and high pressure (salinity = 30-32 ppt).
• The mixed layer is where water is mixed by the wind, varying by latitude.
• The intermediate/transition layer is characterized by salinity and temperature changes transitioning to deep ocean water characteristics.
• The deep layer is consistent globally, with salinity at 34-35 PPT.
• A Thermocline is a drastic change in ocean water temperature profile.
• A Halocline is a drastic change in ocean water salinity profile.
• A Pycnocline is a drastic change in ocean water density profile.
• Upwelling is the movement of deep water towards the surface.
• Upwelling hoists cold, nutrient-rich water to the surface.
• Upwelling produces high productivity and abundant marine life.
• Downwelling is the movement of surface water downward.
• Downwelling moves warm, nutrient-depleted surface water down.
• Downwelling is not associated with high productivity or abundant marine life.
• Sinking salty water near the poles drives these processes.
• Wind can push water away from the shore, causing deep ocean water to rise and replace it.

Ocean Ecology

• Biotic refers to living components.
• Abiotic refers to non-living components.
• The continental shelf is land from the continent submerged under shallow water.
• The twilight zone has barely enough light penetration for photosynthesis.
• The midnight zone has no light.
• The abyss has no light, including the ocean floor.

Biomes and Ecosystems Examples

• Coastal: Kelp Forest.
• Pelagic: Temperate.
• Pelagic: Polar.
• Benthic: Coral Reef.
• Benthic: Vent Communities.

Relationships

• Mutualism: Both organisms benefit.
• Commensalism: One organism benefits, and the other is not harmed.
• Parasitism: One organism benefits, and the other is harmed.
• 10% Rule: Only 10% of the energy from one organism is transferred to the next trophic level in the food chain.

Human Impacts on The Ocean

• 90% of big fish are gone.
• HIPPO is an acronym representing human impacts: Habitat Destruction, Invasive Species, Pollution, Population, and Overharvesting.

Habitat Destruction

• Ocean Acidification: Increased atmospheric CO2 leads to more CO2 dissolving into the ocean.
• In the ocean, CO2 forms carbonic acid, increasing the water's acidity.
• Acidic water dissolves shells, making shelled organisms vulnerable.
• Excess hydrogen ions bond with bicarbonate ions.
• Marine Dead Zones: Eutrophication is a factor.
• Sea Level Rise: Warming temperatures due to increased atmospheric carbon dioxide.
• Ice on land melts, increasing sea levels (floating ice does not impact sea level when it melts).
• Intertidal and coastal biomes are flooded.

Invasive Species

• Often introduced by humans such as the Lionfish (which can lay 2 million eggs), Killer Algae, Green Crab, and Sea Walnut.

Pollution

• Plastics and microplastics are major pollutants.
• Oil harms the immune system, lungs, and oxygen absorption.
• Oil impairs birds' insulation, reducing their ability to stay warm.

Population

• Overpopulation and exponential growth of the human population
• 1 in 7 people rely on seafood as a food source.

Overharvesting

• Humans consume fish as a protein source.
• Bycatch affects other animals.