Oceanography Test 2 Review PDF

Preview

Summary

Review Material for Exam 2. This will help students study for this specific exam....

Description

•

Be able to draw and explain vertical and surface circulation of the atmosphere

•

Be able to predict locations of upwelling and downwelling along coastlines given what you know about global wind patterns

•

Be able to predict wind direction, surface ocean current direction and upwelling anywhere on the planet, just as we practiced in class.

•

Be able to explain the concept of density and understand what controls the density of the atmosphere and ocean water

What is air made up of? • • • •

Nitrogen 78.1% Oxygen 20.9% Argon .9% Carbon Dioxide .039%

Where does air rise away from the planet? •

0º/60º in Northern & Southern Hemisphere

Where does the Antarctic Circumpolar current flow? Why is it important to Antarctica’s ice sheets? • •

Slightly above 60º S in a straight motion (  ) Only current that flows completely around the globe

What are the properties of the least dense air? •

Warm & Moist

What are the properties of the densest air? •

Cold & Dry

What are currents? •

Moving Water

What are waves? •

Moving Energy

Why can’t gyres cross the equator? •

Gyres force currents in circular motion, without letting them move up

Coriolis effect –what effect does it have in each hemisphere? • •

Northern Hemisphere – Turns Right Southern Hemisphere – Turns Left

Ekman transport –what is it, what causes it and what is the result? • •

Turns water more sharply to the left or right 90º Coriolis Effect

Upwelling and downwelling –definitions, causes, and where you might find each. • •

Upwelling – Deep Water rising towards surface -If Ekman transport is pointing  or  away from the land Downwelling – Surface Water sinking away from land -If Ekman transport is pointing  or  towards the land

Why does downwelling happen in the polar regions (there’s an answer for each hemisphere). •

Cold Antarctic water sinks below warmer South Pacific and South Atlantic waters

Is surface water along the equator relatively warm or cold? Use what you know about upwelling and downwelling to explain your answer. • •

Cold Surface Currents carry warm water away from the equator and cool water away from the poles.

Difference between eastern and western boundary currents. Be able to label them on a map. • •

Eastern Boundary Current is Cold Western Boundary Current is Warm

Explain in detail how density controls ocean circulation (why is it like a conveyor belt?) and why is the North Atlantic so important in global ocean circulation (consider the effects of melting of the Greenland ice sheet)? • •

As the seawater gets saltier, its density increases, and it starts to sink Surface water replaces the sinking water, which in turn eventually becomes cold and salty enough to sink.

Characteristics of surface and deep waters (temperature, density, salinity). • •

Most Dense – Cold & High Salt Least Dense – Warm & Low Salt

What is the temperature of the densest water? •

3.98°C

What are the ‘clines’ (thermocline, pycnocline) and why do they exist? • • •

Thermocline – Zone of rapidly changing temperatures Pycnocline – Zone of rapidly changing density Halocline – Zone of rapidly changing salinity

What the common ‘salts’ (ions) in the ocean? •

Sodium & Chloride

What are the controls on salinity in the oceans? • • • • •

Precipitation Runoff Icebergs Sea Ice melting/forming Evaporation

What 2 things are needed for life at the base of the food chain (algae). • •

Nutrients Sunlight

What are the sources of salts and how are salts removed? •

•

Added: -River Discharge -Volcanic Eruptions -Hydrothermal activity in mid-ocean ridge Removed: -Absorption/Precipitation -Sea Spray -Biologic Processes -Hydrothermal activity at mid-ocean ridge

What are some of the key properties of water (what makes it a polar molecule, what is its heat capacity, etc.) • •

Solid, Liquid and Gas State High Heat Capacity - 4,184 Joules of heat for the temperature of one kilogram of water to increase 1degree Celsius

How are currents related to the distribution of life in the oceans? • •

Distribute Heat Control distribution of ocean life...