Warm-up Week 2 # 2 ______ are associated with mid-ocean ridges. a. rift valleys c. extreme temperatures b. mountainous topography d. volcanic structures The gently sloping submerged surface extending from the shoreline toward the deep ocean is called ____. a. continental shelf c. continental rise b. continental slope d. submarine canyon Differences in ocean-surface height can be measured by ____. a. sonar c. submersibles b. satellites d. none of the above

“Composition of Seawater” 15.1

Q: How is ocean water different than fresh water? Dissolved substances Taste! Smell!

Composition of Seawater What it’s ________ of. 3.5% dissolved minerals Salts! MADE

“Salinity.” “Salinus” = salt Salinity = amount of salt dissolved in water Parts per 1000 = ‰ Most of the salt in seawater = common table salt.

Sources of Salts Weathering! Earth’s interior! Chemical weathering of rocks on continents Erosion by rivers Deposition in ocean Earth’s interior! Volcanic eruptions

What affects Salinity? Amount of salt is constant Amount of water changes

Ocean Tempo Variation. Tempo changes with Solar Radiation. Latitude. Tempo changes with depth. Thermocline = “heat” + “slope” Layer of ocean water with fast change in tempo.

Density Variation Density = Mass ÷ Volume ↑ Dense = Sinks ↓ How heavy for size… ↑ Dense = Sinks ↓ ↑ Salinity = ↑ Density ↑ Tempo = ↓ Density

THERMOCLINE PYCNOCLINE

Ocean Layers Layered by density. Transition Zone Surface Zone Thermocline Pycnocline Deep Zone No sunlight Cold & Dense Layered by density. Surface Zone Shallow Mixed (waves & wind)