Climate Weather vs Climate Weather the condition of

Climate

Weather vs. Climate • Weather – the condition of Earth’s atmosphere at a particular time and place. – Short-term: Hours and days – Localized: Town, Region or State • Climate – the average, long-term, conditions of an area. – Two Factors: • Temperature • Precipitation

Temperature • Factors that influence temperature: 1. 2. 3. 4. Latitude Altitude Distance from large bodies of water Ocean currents

Latitude • The distance north or south of the equator, measured in degrees. – Farther North or South you go the colder the temperature gets. • Sun’s rays hit the earth with more of an angle and reflect more of the sun’s energy – angle of insolation. – 3 Climate Zones based on Latitude: • • • Tropical Zone Polar Zone Temperate Zone

Angle of Insolation

Tropical Zone • The area near the equator, between 23. 5° N and S latitude. – Receives direct or nearly direct sunlight all year round. • Warm climate Tropical Zone

Temperate Zones • The areas between 23. 5° - 66. 5° N or S latitude. – Temperatures range from warm summers to cold winters. Temperate Zone

Polar Zones • Extend from 66. 5° – 90° N or S latitude. – Receives the least amount of solar radiation and therefore have the coldest climates. Polar Zone

Altitude • The elevation above sea level. • In the case of high mountains, altitude is a more important climate factor than latitude. – The higher up you go in the troposphere the colder the atmosphere gets.

Distance from Lg. Bodies of Water • Marine Climates – Water warms up more slowly than land; it also cools down more slowly. • Winds from the ocean keep coastal regions from reaching extremes of hot and cold. – Warmer winters and cooler summers • Continental Climates – Have more extreme temperatures due to the distance away from oceans. • Winters cold, summers hot.

Ocean Currents • Streams of water within the oceans that move in a regular pattern. – Warm water from the tropical zone moves toward the polar zones. – Cold currents from the polar zones moves toward the equator.

Factors Affecting Precipitation • The amount of rain and snow that falls in an area each year is determined by how wet or dry the climate is. • Two Factors: 1. Prevailing winds 2. Mountains

Prevailing Winds • Weather depends on the movement of air masses from place to place by prevailing winds. – Different air masses carry different amount of water vapor. • Warm air can carry more water vapor than cold. • Cold air masses are usually dry. – Where an air mass develops also determines the amount of water vapor an air mass carries. • Marine = wet • Continental = dry

Mountains • A mountain range in the path of prevailing winds can also influence where precipitation falls. – Mountains act as a barrier as warm air rises, water vapor condenses and rain falls. • Windward = the side of the mountain facing the wind – Receives lots of rainfall • Leeward = the side of the mountain facing away from the wind – Receives little rainfall (Rain shadow)

Windward vs. Leeward

Climate Change • Throughout Earth’s history, climates have gradually changed. – Ice Ages – glacial episodes • Periods where huge sheets of ice, glaciers, covered large parts of Earth’s surface. • Last ice age ended about 10, 500 years ago. – Interglacials • Periods of warmer weather between ice ages. – It is believed that we are currently in an interglacial right now.

Causes of Climate Change • Natural factors: 1. Continental drift - the movement of landmasses. 2. Changes in the sun’s energy output – energy output changes with an 11 yr cycle • Sunspots – cooler regions of the sun 3. Earth’s Position Relative to the Sun • Angle at which Earth’s axis tilts and the shape of Earth’s orbit around the sun change slightly over long periods of time.

Causes of Climate Change • Human Factors: 1. Greenhouse Effect = gases in the atmosphere trap solar energy and keep the Earth warm; water vapor, carbon dioxide and methane. • Too much of these gases make the atmosphere warmer than needed = global warming. – Burning of fossil fuels add carbon dioxide to the air. 2. Ozone depletion = the loss of the protective ozone layer in the stratosphere that filters harmful UV radiation from the sun. • Chlorofluorocarbons, a group of chlorine compounds, were to blame for the breakdown of the ozone.

Antarctica