hydrogeography + oceans and seas

ratio of all water on earth

97 saline, 3 freshwater

freshwater ratio

30 subsurface water, 69 glaciers ice caps, 1 surface water

world ocean

all oceans of the world together, covers 71 of the worlds surface, continents divide it

oceans names list

pacific, arctic, indian, atlantic, (southern ocean)

sea def

smaller, connected to the ocean

types of seas

inland seas, margine seas

inland seas

in a narrow strait

margine seas

on sides of continent (edge of larger ocean)

ocean criteria

independent basin, avg depth: 2000-4000m or deeper, salt content remains about the same, independent current system

largest ocean

pacific ocean, 166 000 000 km²-1/3 of earths surface

continental shelf

0-200m, rich in petroleum and gas

continous slope

200-3000m

ocean basin

2000-4000m

deep sea trench

8000-11 000m, deepest: mariana’s trench

world avarage salinity

3,5 %, 4x more salty than our blood (dead sea: 35%)(highest red sea 42, lowest baltic sea 7)

factors influencing salinity

evaporation(up), amount of precipitation(down), river inflow(down)

temp of seawater

surface 2-27, deep sea(under 1000m) 2-4

types of seawater movements

waves, tides, ocean currents

waves at open sea

circular path, moves up and down very little/no forward motion, 1 wave: composed of trough and crest

waves with cliffs

distorted movement-giant waves

abrasion

erosion created by giant waves

tides def

regular rise and fall of water level of world ocean due to the gravitational attraction of the Sun and Moon

what causes tides

moons attraction, centrifugal force around the common centre of mass

ocean currents causes

prevailing wind, modified by position of continents, corriolis effect

ocean currents examples

north atlantic drift(warm), gulf stream(warm), canary current(cold)