Ocean Structure and Circulation 1 Ocean Model Temperature

Ocean Structure and Circulation 1

Ocean Model Temperature Warmer Depth Surface Colder Deeper 2

Ocean Model 3

Ocean Model “Warm” shallow surface layer Transition Zone Cold deep layer How do the layers form? 4

Surface Layer Transition Zone Homogeneous Ocean Deep Water 5

Taking the Temperature C Conductivity TTemperature D Depth www. soest. hawaii. edu 6

Ocean Temperature Surface Layer Thermocline = Temperature Transition Zone Change Deep Water • 90% of the total volume of ocean is this cold, deep water. • At depths greater than 1000 m, temperature is approximately 4ºC (even in the tropics!!). windows. ucar. edu Why do layers form? 7

Because of Density Mass per unit volume hawaiianphotos. net Denser 3 3 1020 -1028 19, 300 kg/m Slashfood. com Lighter 1000 100 kg/m 33 8

Ocean Density Surface Layer Pycnocline Transition Zone Pycnocline = Density Change Deep Water • Seawater density is controlled by Temperature and Salinity • In the ocean, Temperature has a greater effect on density windows. ucar. edu 9

Surface Layer Transition Zone Thermocline & Pycnocline Boundary Deep Water 10

Warmed and lit by sun Mixed Surface Layer Boundary Photosynthesis Less Nutrients Cold, Dark, No Photosynthesis , More Nutrients Deep Water 11

Summary Surface Ocean • • Warm Lit by the sun Has photosynthesis Less nutrients Deep Ocean • • Cold Dark No photosynthesis More Nutrients 12