Starter 1.How could the removal of trees and other vegetation impact an environment? a)by increasing oxygen production b)by increasing soil formation c)by increasing transpiration d)by increasing erosion 2.Large quantities of sand can be added to the beach to stabilize the shoreline. Which describes a disadvantage of this process? a)it causes inland erosion b)it is a short-term solution c)it creates a barrier that prevents the tides from occurring along the coastline d)it creates a wall that disrupts the vegetation along the coastline 3.Which is an advantage of safely using uranium as an energy source rather than using coal? a)uranium produces energy without polluting the atmosphere, while burning coal can increase the CO 2 in the atmosphere b)Uranium reduces the amount of thermal pollution, while burning coal can increase the amount of thermal pollution c)Uranium is the most cost-efficient energy resource, while coal is the most expensive energy resource d)Uranium can be easily mined from deep within Earth, while coal is a hard resource to mine from deep within Earth.

Complete Vocabulary for Chapter 21 Section 21.2 (7 words) Section 21.3 (2 words)

Objectives Explain the Koppen climate classification system Describe humid tropical climates Compare and contrast humid mid-latitude climates List the characteristics of dry climates List the characteristics of polar climates Compare and Contrast highland climates with nearby lowland climates

21.2 World Climates  The Köppen climate classification system uses mean monthly and annual values of temperature and precipitation to classify climates.  It is divided into 5 groups: humid tropical climates, dry climates, humid mid-latitude climates, polar climates, and highland climates.

21.2 World Climates  Humid tropical climates are without winters. Every month in such a climate has a mean temperature above 18 o C~64F. The amount of precipitation can exceed 200 cm ~ 79 in per year.  Wet Tropical Wet tropical climates have high temperatures and large amounts of annual precipitation. Tropical wet and dry climates are climates that transition between the wet tropics and the subtropical steppes.  Tropical Wet and Dry

Rain Forest in Malaysia The vegetation in the tropical rain forest is the most abundant found anywhere on Earth. Wet Tropical Climate

African Savanna Tropical Wet and Dry Climate Drought-resistant trees and tall grasses are typical vegetation of a savanna.

21.2 World Climates  Climates with mild winters have an average temperature in the coldest month that is below 18 o C = 64F but above -3 o C = 27F. Climates with severe winters have an average temperature in the coldest month that is below -3 o C.

21.2 World Climates  Humid Mid-Latitude with Mild Winters A humid subtropical climate is generally located on the eastern side of a continent and is characterized by hot, humid summers and cool winters. A marine west coast climate is found on windward coasts from latitudes 40 o to 65 o and is dominated by maritime air masses. Winters are mild, and summers are cool.

21.2 World Climates  Humid Mid-Latitude With Mild Winters A dry-summer subtropical climate is a climate located on the west sides of continents between 30 o and 45 o latitude. It is the only humid climate with a strong winter precipitation maximum.

Mid-Latitude Climates Humid Subtropical Marine West Coast Dry Summer Subtropical

21.2 World Climates  Humid Mid-Latitude With Severe Winters A subarctic climate is found north of the humid continental climate and south of the polar climate; it is characterized by bitterly cold winters and short, cool summers. Places within this climate realm experience the highest annual temperature ranges on Earth.

Mid-Latitude Climates Humid ContinentalSubarctic

21.2 World Climates  A dry climate is one in which the yearly precipitation is not as great as the potential loss of water by evaporation.  In other words, dryness is not only related to annual rainfall, but is also a function of evaporation.  Evaporation is closely dependent on temperature.  There are two types of dry climates: arid (desert) and semi-arid (steppe).

21.2 World Climates  Polar climates are those in which the mean temperature of the warmest month is below 10 o C ~ 50F.  Very little precipitation falls in polar regions. Evaporation, also, in these areas is limited.  There are two types of polar climates: tundra and ice cap.  Polar climates are characterized by low rates of evaporation.

An Ice Cap Climate Is a Polar Climate An ice cap climate is a polar climate in which the average monthly temperature is always below freezing.

21.2 World Climates  In general, highland climates are cooler and wetter than nearby areas at lower elevations.  Conditions of highland climates often vary from one place to another. (Example: south-facing slopes are warmer than north- facing slopes; air on windward sides of mountains are wetter than on leeward side)

Objectives Describe natural processes that can cause changes in climate Explain the greenhouse effect Define global warming List some of the consequences of global warming

21.3 Climate Changes  Volcanic Eruptions The presence of volcanic aerosols (ash, dust, and sulfur-based aerosols) in the air increases the amount of solar radiation that is reflected back into space. This causes Earth’s lower atmosphere to cool.  Ocean Circulation Changes in ocean circulation also can result in short-term climate fluctuations.

Eruption of Mount Pinatubo What you can’t see in this photograph is that volcanic eruptions also send small particles containing sulfur into the air. If the volume of these materials is great enough, it can cause short-term changes in the Earth’s surface temperature.

21.3 Climate Changes  Solar Activity When the sun is most active, it contains dark blemishes called sunspots. The formation of sunspots appears to correspond with warm periods in Europe and North America.  Earth Motions Geographic changes in Earth’s land and water bodies cause changes in climate. Changes in the shape of Earth’s orbit and the tilt of Earth on its axis are other Earth motions that affect global climates.

21.3 Climate Changes  The Greenhouse Effect The greenhouse effect is a natural warming of both Earth’s lower atmosphere and Earth’s surface from solar radiation being absorbed and emitted by the atmosphere.  Global Warming As a result of increased levels of carbon dioxide and other greenhouse gases, global temperatures have increased. This increase is called global warming.

Climate Region Facts and Figures Climate RegionDescription Humid tropical Dry Humid mid-latitude (mild winters) Humid mid-latitude (severe winters) Polar Complete the following on page 119 of your notebook and complete the description: No winter; all months have average temps above 64.4 o F Evaporation is greater than precipitation; always a water shortage Mild winters; average temp of coldest month is below 64.4 o F but above 26.6 o F No summer; average temp of warmest month is below 50 o F Severe winters; average temp of coldest month is below 26.6 o F; average temp of warmest month is slightly above 50 o F

Map Master (textbook page ) Complete the “Map Master Skills Activity” on pages on a separate sheet of paper to be turned in before you leave class. Also, complete the following with the same map: How are savannas and rainforests related? How are steppes and deserts related? What pattern do you see as you go from south to north in eastern North America? What are the typical climate conditions in a rain forest? What is the typical vegetation in a savanna? Which climate region(s) cover more than one of the three climate zones?