Chapter 13: Atmosphere & Climate Change Section 1: Climate & Climate Change

Objectives Explain the difference between weather and climate. Identify four factors that determine climate. Explain why different parts of the Earth have different climates. Explain what causes the seasons

Climate _______ is the _______ weather _______ in an area _____ a long period of time.

Climate Climate is determined by a variety of factors that include ______, atmospheric circulation patterns, oceanic circulation patterns, the local geography of an area, _____ ______, and ______ _______.

Climate The most important of these factors is ______ ____ the ______.

Latitude _______ is the distance ____ or _____ from the _______ and is expressed in degrees.

Latitude The equator is located at _° latitude. The most northerly latitude is the North Pole, at __° north, whereas the most southerly latitude is the South Pole, at 90° _____.

Latitude Latitude ______ ______ climate because the _____ of _____ _____ an area of the Earth receives depends on its latitude.

Low Latitudes _____ solar energy falls on areas ____ the equator than on areas closer to the poles. The incoming solar energy is concentrated on a small surface at the equator.

Low Latitudes In ____ ____ the _______, night and day are ____ about __ _____ long throughout the year.

Low Latitudes In addition, ________ are ____ year-round, and there are __ _______ or ______.

High Latitudes In regions _____ to the _____, the sun is _______ in the sky, _______ the ______ of ______ arriving at the surface. In the northern and southern latitudes, sunlight hits the Earth at an _____ _____ and spreads over a ______ surface area than it does at the equator.

High Latitudes ______ _______ ________ near the poles are therefore ______ than they are at the equator.

High Latitudes At 45° north and south latitude, there is as much as __ ____ of ________ each day during the ______ and as little as _ ____ of _______ each day in the ______.

High Latitudes Near the poles, the sun sets for only a few hours each day during the summer and rises for only a few hours each day during the winter. Thus, the yearly temperature range near the poles is very large.

Low and High Latitudes

Atmospheric Circulation Cold air _____ because it is _____ than warm air. As the air sinks, it ______ and _______. Warm air _____. It expands and cools as it rises. Warm air can hold _____ water vapor than cold air can. Therefore, when warm air cools, the water vapor it contains may condense into liquid water to form rain, snow, or fog.

Atmospheric Circulation _____ energy heats the ground, which warms the air above it. This warm air rises, and cooler air moves in to replace it. This _______ of air within the atmosphere is called _____.

Atmospheric Circulation

Atmospheric Circulation Because the Earth ______, and because different latitudes receive different amounts of solar energy, a ______ of global atmospheric circulation results. This circulation pattern _______ Earth’s __________ patterns.

Global Circulation Patterns Cool air normally sinks, but cool air over the equator ______ ______ because hot air is rising up below it. This cool air is ______ _____ from the equator toward the North and South Poles where it __________ at about 30º north latitude and 30º south latitude.

Global Circulation Patterns Some of the air _____ back to the Earth’s surface and becomes warmer as it descends. This warm, dry air then moves across the _______ and causes water to _________ from the land below, _____ ___ _______.

Global Circulation Patterns At about __º north and __º south latitudes, this air ______ with cold air traveling from the poles.

Prevailing Winds Winds that blow ________ in one direction throughout the year are called _________ _____.

Prevailing Winds Because of the rotation of the Earth, these winds __ ___ blow directly northward or southward. Instead, they are _______ to the ____ in the _______ Hemisphere and to the ___ in the ________ Hemisphere.

Prevailing Winds Belts of prevailing winds are produced in both hemispheres between 30º north and south latitude and the equator. These belts of winds are called the _____ _____. The trade winds blow from the _______ in the Northern Hemisphere and from the __________ in the Southern Hemisphere.

Prevailing Winds Prevailing winds known as the _______ are produced between 30º and 60º north latitude and 30º and 60º south latitude. In the Northern Hemisphere, these are southwest winds, and in the Southern Hemisphere, these winds are northwest winds. The _____ _______ blow from the poles to 60º north and south latitude.

Oceanic Circulation Ocean currents have a great effect on climate because water holds ____ _____ of ____.

Oceanic Circulation The _______ of ______ ocean _______ is caused mostly by ______ and the rotation of the Earth. These surface currents _________ warm and cool masses of water around the world and in doing so, they affect the climate in many parts of the world.

El Niño–Southern Oscillation ___ _____ is the warm phase of the El Niño–Southern Oscillation. It is the _____ occurrence in the _____ ______ Ocean in which the surface-water temperature becomes _______ ____.

El Niño–Southern Oscillation During El Niño, winds in the western Pacific Ocean (which are usually weak) strengthen and push warm water eastward.

El Niño–Southern Oscillation ______ follows this warm water eastward and produces _______ _______ in the _________ half on the ____, but _____ in ________ and ________.

El Niño–Southern Oscillation ___ _____ is the _____ phase of the El Niño–Southern oscillation. It is the periodic occurrence in the eastern Pacific Ocean in which the surface water temperature becomes unusually ____.

Pacific Decadal Oscillation The ______ _______ _______ ___ is a ____-_____, 20 to 30 year _____ in the ________ of warm and cold water masses in the Pacific Ocean. PDO _______ the climate in the northern Pacific Ocean and North America. It affects ocean surface temperatures, air temperatures, and precipitation patterns.

Topography Height above sea level (______) has an important effect on climate. Temperatures fall by about __°C (about 11°F) for every 1,000 m increase in elevation. Mountain ranges also influence the distribution of precipitation. This effect is known as a ____ _____.

Other Influences on Earth’s Climate Both the ___ and ______ ______ influence Earth’s climate. At a solar _______, the sun emits an increased amount of ultraviolet (UV) radiation. UV radiation produces more _____, which ______ the stratosphere.

Other Influences on Earth’s Climate In large-scale volcanic eruptions, ______ _______ gas can reach the upper atmosphere, where it can remain for up to __ years. The sulfur dioxide, reacts with smaller amounts of water vapor and dust in the ___________, forming a bright layer of haze.

Other Influences on Earth’s Climate This layer of haze ______ enough sunlight to cause the global temperature to _______.

Seasonal Changes in Climate The _______ result from the ____ of the Earth’s ___, which is about 23.5° relative to the plane of its orbit.

Seasonal Changes in Climate Because of this tilt the angle at which the sun’s rays strike the Earth changes as the Earth moves around the sun.

Seasonal Changes in Climate During _____ in the Northern Hemisphere, the Earth tilts _____ the sun and receives direct sunlight. Therefore, the amount of time available for the sun to heat the Earth becomes greater. During summer in the Northern Hemisphere, the _______ Hemisphere tilts ____ from the sun and receives less direct sunlight.

Seasonal Changes in Climate During the summer in the Southern Hemisphere, the situation is reversed. Example: Christmas in Australia and Panama = a sunny day at the beach.

End of section 1 Review q’s: 1,2,6,7,10,11,19, 20,26 and 27