Climates of the earth Chapter 3

Chapter 3, Section 1: Earth-sun relationships Climate and weather Earth’s tilt and rotation Earth’s revolution The greenhouse effect

Climate and weather Weather = the condition of the atmosphere in one place during a limited period of time Climate = the term for the weather patterns that an area typically over a long period of time Seattle has a rainy, wet climate. The weather in Seattle is day-by-day. Today there is a 70% chance of rain with a high temperature of 72 degrees Fahrenheit

Earth’s tilt and rotation Earth’s axis = an imaginary line running from the north pole to the south pole through the planet’s center. Earth’s axis is currently tilted at an angle of about 23.5 degrees This affects temperature, the measure of how hot or cold a place is.

Tropics of Cancer and Capricorn

Earth’s rotation Spaceship Earth Earth’s tilt always stays the same. This is why we have seasons (summer and winter) Seasons are most dramatic at the poles Revolution: one trip around the sun (365 days) Equinox = when the sun’s rays fall directly on the Equator ~March 20 ~September 22 Solstice = when the sun’s rays fall on either the Tropic of cancer of the tropic of Capricorn ~December 21 ~June 21

The Greenhouse effect

Chapter 3, Section 2: Factors affecting climate Low/mid/High Latitudes Elevation Winds and Ocean Currents Wind Patterns Ocean latitudes Ocean currents EL NiÑo Landforms and climate

Low/mid/high latitudes Mid Latitude Low Latitude

Elevation Elevation = the height above the level of the sea The higher the elevation, the thinner the air (more oxygen is present at sea level). Thinner air retains less heat. That is why airplane windows are cold during flight.

Wind Patterns Global winds blow in fairly constant patterns called prevailing winds Doldrums are the generally windless bands, also called horse latitudes Doldrums

Ocean currents Just as winds move in patterns, so do cold and warm streams of water. These are called currents Just like the winds, currents are caused by Earth’s rotation, air pressure, and water temperature East Australian Current

EL NIÑO EL NiÑo = the periodic change in the pattern of ocean currents, water temperatures, and weather in the mid-Pacific region IT doesn’t happen every year, but has been happening more frequently since the 70’s Warm water from Australia to north/South America More rain through North/South America Scientists are not sure why this happens, or why it is happening more frequently

Landforms and climate: The rain shadow effect Windward side = side of the mountain facing the wind Leeward side = warmer, drier side of the mountain

Chapter 3, Section 3: World climate patters Climate regions Tropical climates Dry climates Midlatitude climates High-latitude climates Highland climates Climate Changes

Tropical climates Found in or near the tropics (low latitudes) How and wet throughout the year (very humid) Tropical rainforests

Dry Climates Dry areas with sparse plant life Scrubs and cactus Hot by day, cold by night Desserts

Midlatitude climates Experience variable weather patterns and seasonal changes Usually an abundance of rainfall with a variety of natural vegetation Think of the different climates found across the United States

High-latitude climates Freezing temperatures are common throughout the year In the winters, sun light is minimal to non-existent Permafrost = permanently frozen subsoil

Highland Climates High mountain areas, even along the equator Cooler temperatures, thinner air The higher the elevation, the less vegetation

Climate changes Climates gradually change over time, though the causes are unclear During the last 1 to 2 million years, Earth has experienced 4 ice ages Human interaction with the environment also affects climate Burning fossil fuels and pollution have a negative impact on the planet