INTRODUCTION TO OCEANOGRAPHY A. Suryachandra Rao Indian Institute of Tropical Meteorology

Reading Material Only 4 lectures, hence complete book will not be covered Power point presentations will be self explanatory with notes included

Introduction to Oceanography What is Oceanography? Oceanus = ocean graphos = the description of Oceanography = the description of the ocean Oceanus = ocean logos = the study of Oceanology = the science of the ocean Originally accurate, but now much more…

Introduction to Oceanography Some additional confusion of terms: Oceans vs. ocean?

Introduction to Oceanography

Mid-Atlantic Ridge Ocean’s deepest spot Earth’s highest mountain Pacific Ocean Basin, Earth’s largest feature

Introduction to Oceanography Some ocean factoids: Oceans cover 70.8% of earth’ surface Size Atlantic -33,429,000 mi 2 (29.4% of ocean) Pacific - 64,186,300 mi 2 (50%) Indian - 28,350,500 mi 2 (20.6%) Arctic - 5,105,700 mi 2 Average Depth Atlantic – 12,612 ft Pacific - 12,927 ft Indian - 12,598 ft Arctic - 3,665 ft

Introduction to Oceanography

Summary of the relative amount of water in various locations on or near Earth’s surface. More than 97% of the water lies in the ocean. Of all water at Earth’s surface, ice on land contains about 1.7%, groundwater 0.8%, rivers and lakes 0.007%, and the atmosphere 0.001%. NONE, as small as they may be, are unimportant!

Introduction to Oceanography

Oceanography (marine science) is truly an interdisciplinary science

Oceanography The Science or Study of the Oceans Geological Oceanography Geological Oceanography Physical Oceanography Physical Oceanography Chemical Oceanography Chemical Oceanography Biological Oceanography Biological Oceanography

Geological Oceanography Geological Oceanography Study of earth at edge of ocean Study of earth at edge of ocean Formation processes (seafloor) Formation processes (seafloor) Sediments Sediments Rocks & minerals Rocks & minerals Geothermal vents Geothermal vents

Physical Oceanography Physical Oceanography How & why oceans move How & why oceans move Weather Weather Heat transfer Heat transfer Water cycles Water cycles Waves, tides, currents Waves, tides, currents Temperature Temperature

Chemical Oceanography Chemical Oceanography Composition & history of seawater Composition & history of seawater Seawater processes & interactions Seawater processes & interactions Salinity Salinity Dissolved gases Dissolved gases Nutrients Nutrients

Biological Oceanography Biological Oceanography Living organisms Living organisms Organisms relationships with each other and their environment Organisms relationships with each other and their environment

Marine Sediments (geological) created by Living Organisms (biological) That are influenced by Nutrients (chemical) and Currents & Temperature (physical)

20 Why is Oceanography important? The importance of the oceans to physical climate, food supplies and biological stability An extra dimension to human activity And………. Long-term habitability of Earth

21 A Young Science Although oceanography is a relatively young science It is the natural setting to ask fundamental questions about the development of life, and the behavior (or misbehavior) of global climate

Ocean Surface Circulation

The global “conveyor belt”

What role do the oceans play in the climate system? The oceans are important for our current climateThe oceans are important for our current climate

What role do the oceans play in the climate system? The oceans are important for our current climateThe oceans are important for our current climate