intro and oceanography Flashcards
3 main pillars of marine biology
- functional biology
- ecology
- biodiversity
functional biology
how organism carries out basic functions (eg. reproduction)
ecology
how organisms interact with their env
biodiversity
variety of species
what 4 factors determine the density of seawater?
- TEMP
- SALINITY
- depth
- pressure
hypsographic curve
comparing land and oceans
ring of fire
string of volcanoes
-> seismic activity and earthquakes all caused by PLATE TECTONICS
pacific plate
- huge
- its fringes interact with smaller plates around it -> causing activity
Mariana Trench
in NW pacific - deepest trench in world
CONVERGENT boundary -> pacific plate faster than philippine plate
isostasy
rising / settling of bit of Earth’s lithosphere
-> where gravity & buoyancy act on earth’s outer layers to bring them closer together
bathymetry
mapping ocean floor
-> measurement of ocean depths & charting of shape of ocean floor
3 regions of ocean floor
continental shelf - shallow
mid-atlantic ridge
abyssal region - v v deep
describe how and who created the first bathymetric contour map of the world’s oceans
HMS challenger in 1872 for 4 yrs
-> covered 127,600km
-> 1st voyage to record scale of Mariana Trench
-> 4,700 new species of marine life discovered
-> collected DEPTH MEASUREMENTS and “SOUNDED” THE SEA FLOOR using variety of sounding devices
ocean ridges
occupy 33% of oceanic floor and always spreading
4 principal oceans (plus 1)
- pacific
- atlantic
- indian
- arctic
- (southern)
abyssal plains
- gradients < 0.05°
- flattest ocean feature -> only interrupted by seamounts
- covered in deep layers of sediment
sea mounts
-> most are ocean-floor volcanoes that don’t rise above sea level
-> rise abruptly and usually found rising from seafloor to 1,000–4,000 m in height
eg. Mauno Loa sea mount -> as high as mount Everest
guyots
flat topped seamounts -> planed off by wave erosion
hydrological cycle
cycle of water through atm, water and earth
residency time of water in atm (clouds)?
6.9 days