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 colors AQUA – launched in 2002 gathers info on precipitation and evaporation in order to determine if Earth’s water cycle is being affected by climate change.

Remote sensors electromagnetic radiation= EMR

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 senses 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: Dependent 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 0F Multiply 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