Marine Scientists at work

Chapter 2

Marine science today• Oceans currently monitored by: Satellites (in orbit around the Earth)

by use of remote sensors. Remote sensors are instruments that gather information on the features on Earth without being in physical contact with it. These satellites send back info on

• SST’s (sea surface temperatures)• Ice cover • Ocean Depths• Weather conditions• Circulation of currents• Sea surface height (indicates air pressure above and water

temperature)• Productivity (mostly plankton) – using computer-generated colorsAQUA – launched in 2002 gathers info on precipitation and evaporation

in order to determine if Earth’s water cycle is being affected by climate change.

electromagnetic radiation= EMR

Remote sensors

Marine science today

• Remote-sensing satellites are used in search and rescue operations.– NOAA (National Oceanographic and Atmospheric

Administration) A federal agency that monitors the ocean operates SARSAT (Search And Rescue Satellite-Aided Tracking) Locates people in distress in land and on sea.

Scientific method

Scientific Method applied to Marine Science • Stating the problem• Forming a hypothesis• Testing the hypothesis

– Gather materials– Select test method

• Determine what the variables are; design a controlled experiment• Develop experimental (exposed) group and a control (not

exposed) group

• Observations and results of testing• Conclusions

Scientific method• Observations: Gathered through your sensesGathered through your senses

– Types of observations:Types of observations:• Qualitative observations are descriptions that do NOT

involve numbers or measurements.• Ex-The ball is round and red.• Quantitative observations are NUMERICAL

measurements. • Ex- the mass of a book is 600g

• Hypothesis:– Predicts an outcome. Must be a statement.– Must be testable!– Sometimes written as If…Then… statements– IF is the Independent Variable the THEN is the Dependent

Variable.

Scientific Method

• Independent Variable:– What you are testing (changing). The IF of your if

then statement.

• Dependent Variable: – What is it you are measuring. What results are

you looking at. How do you know it works? The THEN of your statement.

• Example: If I put a seed in soil, then it will grow.

Let’s practice• If a plant is exposed to high temperatures then it will not

grow.

• If students study with music on then test scores will increase.

• If fish food is blue then fish will eat less.

– What would be the Control and Experimental Groups for each?

• Procedure/Experiment:– The steps in your experiment.

• Actually doing the experiment

• Data collection and analysis:– Look at data and look for relationships– Construct a graph

• Conclusion:– Decided was your hypothesis supported according

to your data.– Why do you think you saw the results you did

• Retest:– Retest to see if you get the same results

Scientific measurements• Units of Measurement: Meters, Liters and Grams • Length: used for distance (Km, m, cm, mm)

• 1Km = 1000m = 100,000 cm = 1,000,000 mm• Convert Miles to Meters: Miles x 1,609.344• Convert Meters to Miles: Meters / 1,609.344

• 10 Miles = 16,093.44 Meters or 16.09344 Km

• Volume: the space occupied by an object (or liquid)• Solid objects: L * W *H if measureable• Water displacement must be used if not measureable• Liquids: simply use the graduated cylinders

• Mass : the amount of matter contained in an object (Kg, g, mg)

• 1 Kg = 1000 g = 100,000 mg• Density = the amount of matter (mass) contained in a

given space (volume)• D = m/v resulting in units of g/cm3

• Density of liquids can be determined with a hydrometer

Scientific Measurements• Temperature:

– Fahrenheit• Boiling = 212• Room = 68• Freezing =32

– Celsius• Boiling =100• Room =20• Freezing =0

To convert 0F to 0C subtract 32 and divide by 1.8

To convert 0C to 0FMultiply by 1.8 and add 32

Scientific measurements• Specific Gravity = the ratio of the density of a substance to

the density of water (distilled) at 4°C, which is 1.000

• So, a specific gravity of 7.000 means that a substance is 7 times more dense than water, which also means it’s density will be 7.0 g/cm3

• Salinity = The amount of dissolved salt in a substance; avg. ocean salinity is 3.5% = 35 ppt which has a density of 1.025

• ppt= parts per thousand.

• Temperature affects salinity, and both affect the movement

of water in the oceans!

Viewing the microscopic world