Presentation on theme: "M ID T ERM R EVIEW Big Idea #1: Earth Scientists use repeatable observations and testable ideas to understand and explain our planet Big Idea #2: Earth."— Presentation transcript:
M ID T ERM R EVIEW Big Idea #1: Earth Scientists use repeatable observations and testable ideas to understand and explain our planet Big Idea #2: Earth is a Water Planet
B IG I DEA #1: Earth Scientists use repeatable observations and testable ideas to understand and explain our planet.
E NERGY THAT D RIVES E ARTH ’ S 4-S YSTEMS W HAT ’ S THE C ONNECTION ?
H OW D O S CIENTISTS T HINK ? Critical thinking Strong Observations Extensive Documentation Collaboration
C REDIBLE O NLINE S OURCES
D ATA VS E VIDENCE T URN D ATA INTO E VIDENCE factual information as measurements or statistics used as a basis for reasoning something that furnishes proof something submitted to ascertain the truth of a matter.
T YPES OF D ATA Qualities VS Quantity
S HOW M E T HE E VIDENCE Direct Indirect Modeling
H OW DO WE KNOW E ARTH HAD AN ICE AGE ?
E VIDENCE : D IRECT & I NDIRECT Earth’s interior Direct Evidence: Rock Samples Indirect Evidence :Seismic Waves
S CIENTIFIC M ODELS E XPLAINS S CIENTIFIC C ONCEPTS Accurate & Inaccurate
B IG I DEA #2 Earth is a Water Planet
W HY IS THIS IMPORTANT? W HAT IS THE CONNECTION?
L ETS TALK H 2 O V OCAB Surface Tension Desalination Salinity Density Formula Capillary Action Specific Heat Solvent
T HE S CIENCE OF W ATER W ATER ’ S 7-U NUSUAL P ROPERTIES 1. Stronger than normal bonds 2. High Surface Tension 3. High Boiling Temperatures 4. High Specific Heat 5. Universal Solvent 6. Density of the solid is less than at a liquid state 7. Adhesion, Cohesion, Capillary Action
–– F ORMING A W ATER M OLECULE Unequal attraction to bonding electrons Oxygen is a strong electron grabber (high electronegativity) Hydrogen’s electron tends to hang out close to oxygen, leaving H’s positively charged 16 + + H - O +
W ATER IS A P OLAR M OLECULE Unequal distribution of charges on the water molecule make it a polar molecule One end is more negative, and one end is more positive More positive ends More negative end - means partial negative charge + means partial positive charge
E LECTRON D ENSITY IS U NEVEN The electron density around the oxygen atom in a water molecule is about 10X greater than the hydrogen atoms This non-uniform distribution of positive and negative charges, called a dipole, leads to H 2 O unusual behavior 18 Source: Dark Blue = high density Light Blue= low density
U NUSUAL P ROPERTIES
L ETS T ALK O CEAN
W HERE DOES THE SALT COME FROM ?
W HAT I NCREASES & D ECREASES S ALINITY ?
1. O CEAN L AYERS F ROM THE S HORE
1. O CEAN L AYERS D EPTH : 3-Z ONES
2. O CEAN V ARIATIONS Temperature: Thermocline Density: Pycnocline
W ATER ON A G LOBAL P ERSPECTIVE = UNEQUAL HEATING Longitude Latitude
3. O CEAN C URRENTS What drives them? How do they form? Effect of cold currents on climate? What is the role in maintaining Earth’s heat balance? 2-Types: Density currents Deep ocean currents
4. W AVES W AVES TRANSFERS ENERGY FROM ONE POINT TO ANOTHER ENERGY
5. T IDES D AILY CHANGES IN THE ELEVATION OF THE OCEAN SURFACE