Manhattan College SCI 210: Oceanography

Manhattan College SCI 210: Oceanography Chapter 5: The Atmosphere and Ocean Learning Objectives In this chapter, we examine radiational heating and cooling of the Earth-atmosphere system: 1. the interaction of incoming solar radiation with the atmosphere, ocean, and continents, 2. the flow of infrared radiation to space, and 3. the greenhouse effect. We also discuss heat transport by atmospheric and oceanic circulations 1. Understand atmospheric circulation as it relates to ocean circulation. INTRODUCTION: At middle latitudes, prevailing winds blow from west to east. Sea surface temperatures (SST) change relatively little through the course of a year. This stable SST regime dampens the summer-to-winter temperature contrast of air flowing over the ocean to downwind Western Europe. • In Western Europe, the air temperature contrast between summer and winter is less than it is over most of North America. Driving Question: What role does the ocean play in the long-term average state of the atmosphere? WEATHER AND CLIMATE We can think of weather as the state of the atmosphere at some place and time – described in terms of such variables as temperature, precipitation, cloud cover, and wind speed. Climate is popularly defined as weather at a particular place averaged over a specific interval of time. – By international convention, average values of weather elements such as temperature or precipitation are computed over a 30-year period beginning with the first year of a decade. Heating and Cooling Earth’s Surface 1. As Earth orbits the sun, its atmosphere and surface are absorbing energy radiated by the sun (mostly between 0.25 and 2.5 micrometers). 2. Absorption of solar radiation heats the Earth-atmosphere system. 3. At the same time the entire planet is emitting infrared radiation to space (mostly between 4 and 24 micrometers), which has a cooling effect on the Earth-atmosphere system. 4. Over the long term, radiational cooling of the planet essentially balances radiational heating of the planet so that Earth remains in radiative equilibrium with surrounding space.