World Geography 3200/3202 Greenhouse affect and Temperature Patterns

Recap on Seasons Counter Clockwise revolution Will always follow the continuous order of -Spring-Summer- Fall-Winter-Spring- The earth tilts at 23.5 degrees If the earth is pointing TOWARDS the sun: SUMMER If the earth is pointing AWAY from the sun: WINTER

South vs. Northern Hemisphere seasons are reversed in Northern & Southern Hemispheres Example: – Canadian winters are Australia’s summers – The USA’s autumn is South Africa’s spring

Detect patterns in the distribution of temperatures on the earth’s surface

Greenhouse Effect The greenhouse effect is often misunderstood and mistaken for "Global Warming". The greenhouse effect is a good thing. It moderates our temperature. Here on earth the atmosphere acts like the glass on a greenhouse keeping in much of the heat. Consequently here on earth the nights are not as cold. Similar effect as clouds!!!

Planets without atmospheres have an extreme variation in temperature between day and night. Facing the sun, they get the full intensity of the sun = very hot. In the night, absence of radiant sun light & atmosphere = very cold No atmosphere = nothing to hold heat in or block it out!. Remember, here on earth the atmosphere reflects and absorbs almost 50% of radiant energy. (see figure 4.4 p. 57 text)

Generalize how temperatures tend to change as latitude changes Graphic representation shows : as latitude increases Generally temperature decreases!!!!!

Generalize how temperatures tend to change as latitude changes…cont’d Thermal Photography shows the same. #14 p. 59

Describe how the earth’s SHAPE causes temperature to decrease as you move North or South from the equator. At “B” (poles) larger surface area per unit of light Sharper angle causes more deflection. Therefore less heat intensity Fig. 4.3 p. 56 At “A” (Equator) smaller surface area per unit of light More direct hit Therefore more heat intensity Round Shape of the earth gives the different surface areas

An Analogy!!!! If you think about it, it does make sense. Throughout the day, when does the sun feel very hot and temperatures feel hotter In the noon day sun, WHY? The sun is more directly over head!...More direct, intense heat, covering a smaller surface area. While in the evening the sun, the sun is at a smaller angle, it does not feel as hot (cooler!!!!) In the evening, less direct and less intense heat.

Effects on Temperature patterns… so far are: Cloud cover / lack of cloud cover Latitude The earth’s curvature Sunlight-heat concentration or intensity.

Class Activity 1.Number page Open text to page 60. – You can use these two visuals to help answer the question. They will be displayed on the screen, but you may be able to get a better look from the text. – NOTE: Visual one: January, Visual two: July 3.There will be 5 statements a.State if it is true or false b.EXPLAIN why it is true of false 4.There will be two visuals. a.Is it North or South experiencing the seasons b.How do you know?

Assess the accuracy of temperature descriptions… Comment on each of the following statements. Some are incorrect! Pages 59/60 1.The farther South of the equator you go the warmer it gets. TRUE or FALSE? FALSE, Much like the north, the further you move away from the equator the cooler the temperature gets. However, in the south, unlike the north, the differences are not as great or noticeable.

Assess the accuracy of temperature descriptions… 2. Most cold but habitable locations are in the north. TRUE or FALSE? True, if we look at the January map, the colder temperatures represented by the greens and blues appear only in the north

3.The west coast of South and North America are warmer than the east. (Winter – North) TRUE or FALSE?

Assess the accuracy of temperature descriptions… 3.The west coast of South and North America are warmer than the east. (Summer – North) TRUE or FALSE?

Assess the accuracy of temperature descriptions… False, there are a variety of things occurring to make this false. (ie. Latitude, time of year, continent, mountains etc.)

4.WEST COAST temperatures for North America and Eurasia are colder than inland temperatures on the SAME LATITUDE. TRUE or FALSE? False, Generally they are actually warmer, especially during the winter months (oceans!) Marine VS Continental!!

Assess the accuracy of temperature descriptions… 5.Low latitude temperatures are always hot. TRUE or FALSE? TRUE. They are generally always warm/hot. Only one exception…..? High Altitudes at the low latitudes!!!!

Assess the accuracy of temperature descriptions… 6.In the high latitudes, there is a great difference between summer and winter temperatures. TRUE or FALSE? TRUE and FALSE! TRUE. Very noticeable between the January and July maps….. FALSE!!!! Because… It’s only true about the northern hemisphere!!!

Northern or Southern? How do you know?

SouthernSouthern

Additional Class Work: 1.Assigned questions in text: (based on powerpoint 1, 2 & 3) #6-#8 #11 #14

Read about Temperature patterns Try this site