Intro to Oceanography What is Oceanography n The

Intro to Oceanography

What is Oceanography? n The scientific study of the ocean and its inhabitants

n Marine Biology – biological discipline; focused on the biology and physiology of marine organisms

Shouldn’t our planet be called “Water” rather than “Earth”?

of the earth’s surface are oceans n Maximum depth: ca. 11, 022 m (Trieste) (Land: Mt Everest 8, 848 m) n Average depth: ca. 3800 m n Total volume: 1370 x 106 km 3 n Presents 300 times space for life than land freshwater combined. n ~71%

n Only 2% of human food originates from the oceans but present 20% of high quality protein nutrition n Still recent NASA scientist said: “We now know more about the backside of the moon than about the depths of our oceans. ”

Marine vs. Terrestrial Life n Organisms – similar density as environment (salt water) less energy to float/swim… small effect of gravity n Organisms – much higher density than air. High gravity impact (fall down)

n Water supports bodies, no need to put energy in skeletons n Plenty of water for life n Temperature variation low n Need strong skeletal material (animals: bones; trees: trunks) n May become water limited n Temperature varies strongly

Light limited: reflection of light at sea surface and rapid light absorption with water depth n Nutrient limited: nitrate, phosphate, silicate, iron n n Light energy substantially higher than in aquatic systems, low absorption by air n High nutrient concentrations in natural soils

Major part of nutrient cycling in the dark deepsea n Physically unstable habitats n n Nutrient cycling in soil close to plant uptake n Physically stable environment