Wednesday, January 17, 2018 (Discussion - Introduction to Oceanography, The Composition of Seawater, Salinity; Begin DE Techbook Unit – Studying the Hydrosphere)

Complete the following sentence: The Launch Pad Wednesday, 1/17/18 Complete the following sentence: We know more about the surface of the planet Mars than we know about ____________. our own oceans

Welcome to the Second Semester! Announcements Welcome to the Second Semester!

Summative or Formative # Assignment Summative or Formative # Date Issued Gone Missing Day Last Day Accepted

The Hydrosphere

The “hydrosphere” is the water component of the Earth, including both saltwater and fresh water.

“Oceanography” is the study of our saltwater oceans.

The Composition of Seawater Seawater consists of about 3.5% (by weight) dissolved minerals. Salinity refers to the total amount of solid material dissolved in water. Salinity is typically expressed in parts per thousand (‰) The average salinity of seawater is 35‰, with the major constituent being sodium chloride

The Composition of Seawater Sources of Sea Salts chemical weathering of rocks on the continents and subsequent inflow from rivers outgassing from volcanic eruptions

The Composition of Seawater Processes Affecting Seawater Salinity Variations in salinity are a consequence of changes in the water content of the solution. Processes that decrease salinity (add water) include: precipitation runoff from land icebergs melting sea ice melting

The Composition of Seawater Processes Affecting Seawater Salinity Variations in salinity are a consequence of changes in the water content of the solution. Processes that increase salinity (remove water) include: evaporation formation of sea ice

The Composition of Seawater Surface salinity in the open ocean ranges from 33‰ to 38‰.

Processes Affecting Seawater Salinity decrease seawater salinity increase seawater salinity

A desalination plant that removes salts and other chemicals from sea water to produce fresh water.

Begin Discovery Education Unit Unit: Studying the Hydrosphere Concept: Ocean Water Go to www.discoveryeducation.com and login. Scroll down to the bottom of your homepage and click on the “Science Techbook” link. Find the Unit titled “Studying the Hydrosphere” and click on it. Choose the Concept titled “Ocean Water.” Begin reading, watching the videos, and doing the activities. When you reach the bottom of the page, click the NEXT button and proceed through the Concept.