Energy Transfer in the Climate System

What is a system? A group of interdependent parts that work together to form a single functioning whole. In an open system, energy and matter cross the system’s boundary. In a closed system, energy only crosses the system’s boundary. Earth behaves like a closed system.

Feedback Loops Process in which part of a system’s output is returned, or fed back, to the input.

Positive Feedback Loop Acts to increase the effects of the interacting parts, leading to larger and larger changes.

Negative Feedback Loop Decreases the effects of the interacting parts and helps to maintain a system’s equilibrium. Example: see pg. 313 – Global Warming

Electromagnetic Radiation Energy that travels as waves that move outward in all directions from a source. Includes infrared radiation, ultraviolet radiation, radio waves, X-rays, gamma rays, and visible light.

Types of Energy Transfer Radiation Transfer of thermal energy / heat as electromagnetic radiation Conduction Transfer of thermal energy from hot to cold surface Convection Transfer of energy by highly energized molecules moving from one place to another (in liquids and gases only)

Radiation, Conduction & Convection

Energy Transfer in the Atmosphere (p. 315)

Energy Transfer in the Ocean Thermohaline Circulation Three-dimensional pattern of ocean circulation driven by wind, heat, and salinity (salt levels) that is an important component of the ocean-atmosphere climate system.

El Nino & La Nina National Geographic insert P. 318-319

El Nino vs. La Nina Normal trade winds near equator blow to the west. Thus: warm surface water piles up in west Pacific cold nutrient-rich water wells up in the east Pacific. Rainfall in west Pacific El Niño occurs when trade winds are slackened or reversed warm surface waters remain in East Pacific. Disaster for sea life who depend on nutrient upwelling and on animals that feed on them. Drought in Australia and Indonesia Roots drown for land plants and animals suffer in the East Pacific because of lots of rain (too much!-landslides common). Worldwide climatic ramifications

La Nina Year (normal)

El Nino Year

Earth’s Energy Budget Description of total energy exchange within a system. Summary of how energy from the Sun enters, moves through, and leaves the Earth system.

Earth’s Albedo

Work: P. 314 #1-4 P. 317 #5-8 P. 322 #1-8