自然地理学 英文

NaCl The most abundant salt in seawater is ________, but there are many other salts present in the form of ions.
The average salinity of seawater is _____ 35 ppt. Therefore, for every 1,000 ml water, there are ___ 35 grams of dissolved salts. Near the equator salinity is __________ lower than average due to greater precipitation ___________________. lower Near the poles salinity is __________ than average due to melting sea ice _______________. higher In the Mediterranean the salinity is __________than average due to __________. evaporation
The Topex/Poseidon _____________ satellite orbits 1331 km above the Earth, gathering information about the oceans.
Sonar _____________ maps ocean floor topography by timing how long it takes sound waves to bounce off the ocean floor.
submersibles Underwater vessels called _________________ investigate the deepest ocean trenches.
Sonar (also called echo-sounding)
• Sound waves travel
Arctic • The _______Ocean near the north pole, and the ____________ Antarctic Ocean near the south pole contain vast expanses of sea ice.
Methods of Studying the Ocean
Physical Oceanography
Chapter 15
Major Oceans
• The three major oceans are :
Pacific 1._______-largest, deepest, coldest, least salty. 2.__________second largest, shallow, warm, Atlantic salty. 3. _________Indian intermediate in depth, temperature, and salinity.
The ocean’s surface water temperature varies with the amount of solar radiation received, which is primarily a function of latitude.
• The thermocline is the layer of ocean water between about 300 meters and 1000 meters where there is a rapid change of temperature with depth. • The thermocline is a very important structure because it creates a barrier to marine life.
1,454 m/s
how fast in seawater?
• How deep is the
water if it takes ten seconds for the sound wave to go fቤተ መጻሕፍቲ ባይዱom ship to ocean floor and back to ship? 7,270 m
Natural Processes Affecting Salinity
The salinity here would likely be: A. 35 ppt B. 34 ppt
C. 36 ppt
Colorful Seawater •
•
What makes the ocean water in the picture to the left different colors? differences in depth Why would a shrimp that appears bright red at the surface appear black at greater depths, and why might this be beneficial?
Longer (red) wavelengths are absorbed before reaching deep water. Shrimp can hide and not become a meal.
15.1 The Composition of Seawater
Ocean Temperature Variation
Calculation: (10 s times 1,454 m/s divided by 2 )
submersible • The picture below is of a _____________.
Salinity
The amount of salt per unit water is known as salinity.