OCEANS Pages 661-668

Ocean Water is not pure! Two main dissolved gases = N2 and O2. CO2 (in large amounts) Other atmospheric gases (in small amounts)

Gases enter the ocean from… the atmosphere (most O2 enters this way) underwater volcanoes marine organisms streams and rivers

Temperature and Dissolved Gases Gases dissolve more readily in COLD water. Water at the surface of the ocean in COLD regions dissolve larger amounts of gases than water in WARM tropical regions. Gases can return to atmosphere from ocean (evaporation).

Carbon Sink Ocean = 60X as much Carbon as atmosphere CO2 trapped in ocean for years and years Ocean is a carbon sink….b/c ability to dissolve and contain a lot of CO2 CO2 traps thermal energy, so ocean is important in climate regulation

Dissolved Solids Ocean water = 96.5% pure water and 3.5% dissolved solids called sea salts Dissolved solids made of 75 elements. Ocean water mostly…Cl, Na, Mg, S, Ca, K 85% of solids is HALITE Trace elements(in small amounts) Au, Zn, P

Sources of Dissolved Solids Volcanic eruptions Chemical weathering of rock on land Chemical reactions b/t sea water and newly formed sea floor rocks

Salinity of Ocean H2O Salinity – measure of the amount of dissolved salts and other solids in a given liquid Measured by # grams of dissolved solids in 1,000 grams ocean water (parts per thousand or ‰) Higher salinity = better conductivity

Factors that Change Salinity Precipitation = fresh water Ocean water evaporates or freezes…only H2O molecules removed Rate of evaporation higher than precipitation = salinity of surface water increases Equatorial water = salinity lower Salinity ranges 33‰ to 36 ‰, average 34.7 ‰

Temperature of Ocean Water Varies with depth and location on the surface Temperature range is affected by amount of solar energy and movement of water in the ocean