WednesdayFebruary 13, 2013

(Ocean Temperature and

Density)

The Launch PadWednesday, 2/13/13

What is “salinity?”

Describe the term as it applies to Earth’s oceans.

Salinity is the amount of dissolved minerals in a given amount of water.

Ocean water averages 3.5% mineral content, or

350/oo (ppt)

The Launch PadWednesday, 2/13/13

Determine the effects the following processes have on the

salinity of the ocean water in their immediate area:precipitation

evaporationformation of sea

icemelting of icebergsrunoff from land

decreases salinityincreases salinityincreases salinitydecreases salinitydecreases salinity

Announcements

??

Happy National Get a

Different Name

Day!

“ Hello, my

name is Missy”

AnnouncementsI will be available after

school from 4:45 until 5:30.

Assignment Currently Open

Summative or

Formative?Date Issued Date Due Date Into

GradeSpeed Final Day

Quiz 17 S2 2/1 2/1 2/1 FRIDAY

WS – Metamorphic

RocksF11 2/6 2/8 FRIDAY

Lab – Metamorphic

RocksF12 2/7 2/9 FRIDAY

Quiz 18 S3 2/8 2/8 2/11 2/25

Lab – Mixed Rocks F13 2/11 2/12 FRIDAY

WS – Introduction to Oceanography

- SalinityF14 2/12 2/13 FRIDAY

Recent Events in ScienceNASA'S Orion Lands Safely on Two of Three Parachutes in Test

Read All About It!www.nasa.gov/home/hqnews/2013/feb/HQ_13-048_Orion_Chute_Test.html

NASA engineers have demonstrated the agency's Orion spacecraft can land safely if one of its three main parachutes fails to inflate during

deployment. 

The test was conducted Tuesday in Yuma, Ariz., with the parachutes attached to a test article. Engineers rigged the parachutes so only two

would inflate, leaving the third to flag behind, when the test capsule was dropped from a plane 25,000 feet above the Arizona desert. 

"Today is a great validation of the parachute system," said Chris Johnson, a NASA project manager for Orion's parachute system. "We

never intend to have a parachute fail, but we've proven that if we do, the system is robust for our crew to make it to the ground safely." 

Orion's parachutes will perform in ways no landing system for a spacecraft carrying humans has been required to do before. Because Orion will return to Earth from greater distances, it will reenter Earth's

atmosphere at speeds of more than 20,000 mph. After re-entry, astronauts will rely on the parachutes to slow the spacecraft for a

gentle splashdown in the Pacific Ocean. 

This 21,000-pound capsule needs only two main parachutes and one drogue parachute. But NASA spacecraft, particularly those carrying

humans, are designed to keep working when something goes wrong. So, Orion will be equipped with three main parachutes and two

drogues, providing each system one backup parachute. 

Ocean Temperature Surface water temperature varies with the amount of solar radiation

received.Lower surface temperatures are found in high-latitude regions.Higher surface temperatures are found in low-latitude regions.

The unique thermal

properties of seawater make it

resistant to temperature

changes.However, global warming could

eventually influence ocean temperatures.

Ocean Temperature Variation with Depth In low latitudes, there is a high temperature at the surface,

with a rapid decrease in temperature with depth. This indicates the presence of a thermocline.

In high latitudes, there are cooler surface

temperatures with no rapid change in

temperature with depth.

Variations in the Ocean’s Surface Temperature and Salinity with Latitude

Figure 14.3

Ocean Density Density is the amount of mass a material contains in a given

volume of space.Density determines the water’s vertical position in the ocean.

Factors affecting seawater density:

•temperature (the greatest

influence) •salinity

Ocean Density Variations with Depth In low latitudes, there is

low density at the surface, with the density

increasing rapidly with depth because of colder water. This indicates the

presence of a pycnocline. In high latitudes, we find high-density (cold) water at the surface with little change in density with

depth.

Ocean “Layering” Due to Density The oceans have a three-layered structure according to density.

The Surface Mixed Zone is warmed by the Sun and extends to a depth of 300 meters.

The Transition Zone lies under the surface mixed zone and is where the thermocline and pycnocline are found, if present.

The Deep Zone in under the transition zone when where sunlight never reaches. Temperatures here are just a few degrees above freezing, and

the water density is constantly high.

About one-third of the carbon dioxide gas induced into the atmosphere by humans ends up in the

oceans. This results in ocean water gradually becoming more acidic. This is threatening a variety of organisms, including food-chain microbes and corals.

Worksheet

Ocean Temperature and Density

Video

DisneyNatureOceans(Part 2)