midterm 1 Flashcards
Rugose corals
went extinct becasue of CO2 in atmosphere, lost calcified corals find these all over the rockies
When did the rockies uplift
136 million ears ago
When did we see the first unicellular eukaryotes (stromatolites)
1.8 bya
What environmental factor effects the water the most
WIND
Known for the birth of natural history observation
Aristotle
What was Linnaeus know for
First systematic classifications and devised naming scheme(gensu and Specific epithet)
Known for his proposed system of phyla (organized living species into groups) and helped establish the first system of describing benthic habitats
Georges Cuvier `
Who where the first to navigate the ocean
Polynesians
they used stars and currents
Earliest map
Ptolemy in 150 AD
What is longitude and how is it measured
lines that run from north to south, used to show distance from east to west measured using clocks
What is latitude and how is it measured
Horizontal lines running from east to west and tell distance from north to south and is measured with stars and suns position
What was the main issue in navigating the oceans initially
clocks where not able to go on ships and so measuring longitude was very difficult
Who was responsible for the first clocks that could be used on ships
Harrison
What is the azoic theory and who developed it
No life deeper than 300 fathoms developed by edward forbes
BONUS
disputed by micheal sars
Theory of coral reef subside
charles darwin theorized that land subsides and coral grew like living things ontop
Two main discoveries made by the challenger expedition
discovered the Marianas trench (deepest point on earth 11 000m) and disputed the bathybiys theory(primordial slime)
What portion of the earth surface is ocean
70%
80% in southern hemisphere and 61% in northern hemisphere
Who was the first person to go the bottom of the marianas trench and how
James Cameron in his deepsea challanger
What are marginal seas and what affects them
Parts of the ocean that are highly effected by the continents affected by
- regional climate
- precipitation and evaporation balance
- river input of fresh water or dissolved solute
- limited exchange with open ocean
- geological history
Topographic features
continental shelf marginal sea trench abyssal plain Mid-ocean ridge seamouont abyssal plain continental rise slope shelf coastal plain
Where is the oceanic crust formed and destroyed
created at ridges and destroyed at subduction
causes continental drift
Proof of continental drift
- fossils of similar fauna on different continents
- Seafloor mapping and radiometric dating (sea floor is relatively young)
- Magnetic anomalies (bands on floor with different magnetic moments)
Water properties
- dissolving power
- high heat capacity
- high heat of vaporization (lots of energy required to heat water by 1 degree)
- high heat of fusion (absorbs a huge amount of heat before ice melts)
Vertical temperature gradients in open tropical ocean
surface layer is high temp and thermocline is long and then there’s a relatively steep drop off
Vertical temperature gradient shallow temperate oceans
shallow thermocline in summer and in winter steady temperature no thermocline
Additions of heat in the ocean
Latitudinal gradient of heat (most heat at equator)
geothermal heating
internal friction
water vapor condensation
losses of heat in the ocean
back radiation off surface
convection of heat to atmosphere
evaporations
Salinity
how much dissolved inorganic solids per 1000g of seawater
Controls for salinity
positive
-evaporation and sea ice formation water is taken from the ocean and salt is more concentrated
negative
-precipitation and river runoff
pure water is added to the ocean diluting the salt
How salinity is measured
Chemical titration (chlorinity is measured and chlorinityx2 is salinity)
conductivity (run current though water salt is a conductor more salt more conductivity)
Index of refraction (density water with more salt is denser and more buoyant)
also use a CTD- conductivity temperature depth instrument it measures how conductivity changes with temperature
Forchhamers principle
regardless of where you are the oceans elemental ratios are the same this is because residence time is in the millions of years and mixing is good
Brinicle
The finger of death water gets cold and dense and moves down and salt also moves down because of its increased density making water freeze down in a finger like movement
Currents
streams of water moving through the ocean, can be long and permanent like Gulf stream and also smaller episodic flows
Gyres
Spiraling circulations thousands of miles in diameter they are rimmed by large permanent currents
What are the 5 main gyres and there main streams
North pacific subtropical gyre (California, North equatorial, Kuroshio, North Pacific draft)
South pacific subtropical gyre ( Peru, South equatorial, east Australian, south pacific)
North Atlantic subtropical gyre ( Canary, North equatorial, Gulf stream)
South Atlantic subtropical gyre (South equatorial, South Atlantic)
Indian subtropical gyre (south Indian, south equatorial, west Australian)
Eddies
smaller temporary loops of swirling water that travel long distances before dissipating
How deep do winds drive currents
100 m (their effects can reach the bottom of the ocean)
What drives the circulation of the atmosphere
THE SUN (sun warms the surface of ocean and the ocean warms the atmosphere)
Coriolis Effect
due to earths rotation, on a large scale is causes moving objects to appear to bend from a straight path, affects movement of air water and planes
In the north hemisphere force deflect objects to the right
In the south hemisphere force deflect objects to the left
Thermohaline circulation
deep ocean currents driven by differences in waters density, which controlled by temperature and salinity
drives the global conveyor belt
AMOC
Atlantic meridional overturning circulation
How are waves formed
friction with air
4 principles of wave formation
- very little net movement of water, only energy moves
- water particles move in circular orbits
- orbit diameter decreases with distance from the surface
- Waves reflect from objects with no energy loss
wave dimensions
wave length =L (crest to crest) amplitude =H period =t Velocity= V(=L/t for waves in deep water) Depth =D (1/2 length) Height from trough to crest
difference between deep waves and shallow waves (2)
- water depth is less than half length waves “feel bottom” orbit becomes elliptical and particles are displaced
- when wave breaks if height is more then 1/7 of length wave is unstable and collapses
