1. A case study of geography teaching in senior three.
Teaching objectives enable students to understand the weakening effect of the atmosphere on solar radiation through learning; The heat preservation function of the ground atmosphere; Cultivate students' autonomous learning ability and the ability to identify, extract and process various useful information from various materials in the learning process; Through learning, students pay more attention to the environment in which human beings live and the environmental problems that human beings face.
Teaching suggestion
Teaching analysis of atmospheric thermodynamic behavior
The key content of this textbook is the thermal effect of the atmosphere, in which the thermal insulation effect of the atmosphere is the difficult content of this section.
The thermodynamic function of the atmosphere includes two aspects:
First, the weakening effect of the atmosphere on solar radiation. Pay special attention to which function is selective and which function is not. What are the key substances in the atmosphere that can be absorbed, reflected and scattered? This weakening effect makes the daytime temperature not too high, but this weakening effect varies from place to place. The textbook clearly points out that due to different solar altitude angles, the distance of solar radiation passing through the atmosphere is different, the degree of being weakened by the atmosphere is different, and the solar radiation reaching the ground will be different.
Second, the heat insulation effect of the atmosphere needs to be clear about the differences and connections between solar radiation, ground radiation and atmospheric radiation. The difference between the sun, the earth and the air is that the temperature of the ground is located in the sun and the temperature of the atmosphere is located on the ground, so solar radiation belongs to short-wave radiation, while ground radiation and atmospheric radiation belong to long-wave radiation, so it can be absorbed by carbon dioxide and water vapor in the atmosphere. The relationship between solar radiation, ground radiation and atmospheric radiation lies in that nearly half of solar radiation reaches the ground through the atmosphere, and the ground absorbs solar radiation to heat up, while radiating outwards to transfer heat to the atmosphere. After absorbing ground radiation, the atmosphere heats up and radiates outwards, and atmospheric radiation has two parts, and a small part is lost to space; Another part of the radiation reaches the ground, called atmospheric inverse radiation, which compensates the ground to some extent.
Radiant heat dissipation.
From the above analysis, we can see that solar radiation is the energy source of the earth, and the atmosphere freely puts solar radiation into it, so that the ground can fully absorb solar radiation and radiate the absorbed energy into the atmosphere in the form of long waves. Therefore, the ground is the main direct heat source of the atmosphere, and the atmosphere fully absorbs long-wave radiation from the ground and radiates most of the energy to the ground in the form of long waves, thus keeping the ground warm. Knowing the weakening and heat preservation of the atmosphere can explain why the temperature difference between day and night on the earth's surface is small. The weakening effect of the atmosphere on solar radiation makes the temperature not too high during the day, while the heat preservation effect of the ground atmosphere makes the temperature not too low at night, so the temperature difference between day and night is not too big.
Teaching Suggestions on Atmospheric Thermal Function
It is suggested that the teaching methods such as conversation, discussion and study guidance should be adopted. First of all, guide students to read relevant images in textbooks to explain the distribution of solar radiation wavelength; Secondly, starting with the temperature difference between day and night between the earth and the moon, guide students to analyze the essence of the difference between them. This shows the thermodynamic function of the atmosphere. How does the atmosphere weaken? Teachers can use video materials or guide students to read textbooks, and combine specific examples, such as low temperature on cloudy days in summer, blue skies and strong ultraviolet radiation on the Qinghai-Tibet Plateau, to explain the three forms and characteristics of atmospheric weakening. Through the conclusion that solar radiation decreases from low latitude to two poles, students are guided to analyze that the main factor affecting the atmospheric attenuation effect is the solar altitude angle.
Teaching suggestions on atmospheric heat insulation effect
With regard to the heat insulation function of the atmosphere, teachers can illustrate the principle of heat insulation with examples from life, such as down jackets and quilts worn in winter. Guide students to read relevant images provided in textbooks or self-made courseware, and analyze the radiation relationship among the sun, the earth and the atmosphere. In particular, students should be clear that solar radiation belongs to short-wave radiation, ground radiation and atmospheric radiation belong to long-wave radiation, and atmospheric inverse radiation plays a role in isolating the ground and also belongs to long-wave radiation. With regard to the knowledge of global heat balance, teachers should focus on the changes of some components in the atmosphere caused by human activities, which will affect the radiation of the sun, the earth and the air, make the global climate warm, and increase the ultraviolet rays reaching the ground, threatening human survival. For this part of the content, the teacher can arrange for students to find relevant information after class in advance, and everyone can discuss it in class. Through discussion and analysis, students can pay more attention to human living environment. Teaching analysis of global heat balance
For the global heat balance, we should make the following three points clear: first, from the global average for many years, the earth's income and expenditure on heat are equal; The second is the influence of global heat balance on human activities, that is, global heat balance makes the global average temperature stable for many years, which is beneficial to human survival and activities; Third, the impact of human activities on the global heat balance, that is, human activities increase the content of carbon dioxide in the atmosphere, affect the global heat balance, and aggravate the global warming trend, thus having a series of impacts on global ecological and economic development. By analyzing the relationship between atmosphere and human activities, students are educated in the coordinated development of man and land.
2. Examples of geography teaching plans in senior three.
Teaching objectives 1. Knowledge target
1. Understand the causes and hazards of four major geological disasters (earthquake, volcanic eruption, debris flow and landslide);
2. Understand the relevance of geological disasters and the importance of monitoring and preventing geological disasters;
3. Understand the direct and indirect effects of human activities on geological disasters and the scientific research progress of geological disasters.
Second, the ability goal
1. Cultivate students' comprehensive analysis ability and correctly evaluate the relationship between geological disasters and human activities;
2. Enhance students' ability to cope with geological disasters;
3. Ability to read pictures and get information.
Third, emotional goals.
Strengthen students' scientific outlook on life, so that students have the awareness of environmental protection and disaster prevention and reduction.
Multimedia courseware of teaching tools
Prepare to divide students into groups before class so as to collect all kinds of data related to geological disasters.
teaching process
Courseware demonstrates Tangshan earthquake pictures with dubbing.
The teacher guided us to see some pictures and written materials about the Tangshan earthquake just now. We find that the changes in the land environment are sometimes extremely dramatic. These natural phenomena are the expression of the internal force of the earth, and they often cause great damage and threat to the human environment. We call it geological disaster. Please think about it. How much do you know about geological disasters? Can you give me an example?
Student's answer
The courseware demonstrates the catalogue of major geological disasters.
Watch the basic knowledge of video earthquake.
Why do earthquakes happen on the earth?
Students answer (plate edge, crustal instability)
Watch the video of the cause of the earthquake.
The teacher summed up the causes of earthquakes, so we can easily know the distribution of earthquakes in the world.
Look at the picture to show the "World Earthquake Distribution Map" and "Six Plate Distribution Maps"
Questioning Although we seldom visit the earthquake site in person, we know through research that the earthquake is actually a process in which the earth releases rapidly in the form of seismic waves on the fault zone of the earth's crust. Please use your imagination. What harm will the earthquake cause?
Students discuss in groups and answer briefly.
The teacher added that it is easy for us to see the direct harm caused by earthquakes, but in fact earthquakes often bring other indirect harm and often cause more serious losses. Such as fires caused by earthquakes, plagues, etc.
Transition just now, we looked at the world earthquake distribution map. In fact, the distribution of volcanoes and earthquakes in the world is basically the same. Let's learn some basic knowledge about volcanoes.
Play the video "Basic knowledge of volcanoes"
The teacher leads the questions. By watching the video, we learned something about volcanoes. Please recall, what are the classifications of volcanoes? What do you think this classification means?
Students' Thinking and Simple Answers
The teacher concluded that scientists put forward dormant volcanoes, which just shows that we don't know much about the law of volcanic eruption. To understand this knowledge exactly, more and deeper scientific research is needed.
Why are Italy and Japan countries with frequent volcanic activities? What is the cause of volcanic eruption?
Student's answer
The courseware demonstrates the animation of plate collision.
Group discussion volcanic eruption is also a very destructive geological disaster. However, apart from the harm, what are the advantages of volcanic eruption? Please give an example.
Courseware demonstration should have a correct evaluation of the geological disaster of volcanic eruption. (1) From the perspective of disasters (2) From the perspective of resources.
It is a very harmful geological disaster to undertake transitional earthquakes and volcanic eruptions. They are the embodiment of energy release and magmatic activity in the earth, but the other two kinds of geological disasters can not be ignored. These are landslides and mudslides.
Please look at the picture below and think about the following questions.
Student's answer
The teacher summed up that geological disasters have brought great harm to people's lives and production, and we should actively defend ourselves to minimize the losses caused by these hazards. China has a vast territory, complex terrain and common geological disasters.
Please watch the animated demonstration of the geological disaster map of China.
It seems sensational to ask so many questions about geological disasters, but these are unavoidable facts. How should we protect ourselves? Please watch the video below to see what Japan has done in this regard.
Play a video to defend against the earthquake disaster in Japan.
Discuss in groups how people in earthquake-prone areas should defend against earthquakes. What should be done in the three stages before, during and after the earthquake? )
For the teacher's summary, please refer to the expanded material "Response when an earthquake occurs", and then summarize the preventive measures of earthquake disasters (three aspects).
3. Examples of geography teaching plans in senior three.
First, the necessity of cross-regional allocation of resources (reasons) (1) The regional distribution of natural resources is very uneven and generally does not flow between regions.
(2) The demand for natural resources in each region often does not match the natural resources in this region.
Large-scale Cross-regional Resource Allocation Project in China
West-to-East Gas Transmission, West-to-East Power Transmission, South-to-North Water Transfer, and North-to-South Coal Transportation.
Conclusion: In order to adapt to the balance between regional development and natural resources supply, it is necessary to allocate resources across regions.
Two. Summary of West-to-East Gas Transmission Project
1. Basis:
Natural gas resources in Xinjiang
2. Target market:
Yangtze River Delta and Pearl River Delta
3. Components:
Natural gas development and construction, gas pipeline construction and user pipe network construction
4. Two lines:
Schematic diagram of the first line of west-to-east gas transmission project
Third, the regional differences of energy production and consumption in China.
-the respective advantages of the eastern region and the western region have not been fully exerted, which has affected the further development of each region.
(1) The eastern coastal areas are economically developed and have a great demand for energy, but the energy is relatively poor, which makes the economic advantages not fully exerted.
(2) Limited by the economic level, the rich energy resources in the western region cannot be fully developed and utilized. The contradiction between "production" and "elimination" between western and eastern regions.
4. Examples of geography teaching plans in senior three.
Knowledge and skills 1. Understand the basic connotation of the integrity of natural geographical environment.
2. Understand the overall performance of the natural geographical environment.
3. Enable students to establish a universal view, fully consider the relationship between various geographical elements in the use and transformation of nature, and avoid taking one event and affecting the whole body.
Process and method
1. Autonomous learning, analysis and discussion.
2. Inquiry and activities to understand the integrity of the geographical environment.
3. Using landscape pictures to analyze the integrity of geographical environment.
Emotions, attitudes and values
Help students establish the idea that things are generally related, and make overall consideration in the use of nature.
Emphasis and difficulty in teaching
● Teaching focus
1. The overall reason of geographical environment.
2. The interaction between geographical elements has produced new functions.
3. The evolution of natural geographical environment is unified.
4. The elements of physical geography and environment will "affect the whole body".
● Teaching difficulties
The interaction between geographical elements has produced new functions; The natural geographical environment has a unified evolution process.
teaching process
[Introduction to New Lessons]
Teacher: Students, in the first chapter, we learned "the cosmic environment of the earth". Now we are going to study "natural geographical environment". The word "environment" means the surrounding situation relative to a central thing. So what is the difference between the central things of these two "environments"?
Health: the center of the former is the earth, and the center of the latter is human beings.
Teacher: Yes! We know that the geographical environment is composed of many elements. In previous studies, our eyes have always been on a single geographical element, but the elements that constitute the geographical environment are mutually influential and restrictive, and the geographical environment is holistic. Today, we will learn about the integrity of the geographical environment.
(blackboard writing) Section 1 Integrity of natural geographical environment
(Play the video clip "Xishuangbanna Natural Scenery")
[Teacher's explanation]
Teacher: The students enjoyed the charming tropical scenery of Xishuangbanna. Please think about the geographical elements contained in the natural landscape in the film.
Health: includes five geographical elements: atmosphere, water, rocks, biology and soil.
Teacher: Not bad. So do these five geographical elements meet by chance in space? If not, what is the connection between them?
Health: These five geographical elements are not simply brought together, but through the process of water cycle, biological cycle and lithospheric material cycle, material movement and energy exchange are carried out among them, thus forming a mutual infiltration and interaction whole.
Teacher: Good. Please give examples to illustrate how these geographical factors restrict each other and how to maintain the consistency of Xishuangbanna landscape.
Xishuangbanna has a tropical monsoon climate and abundant precipitation, so there are many kinds of plants and corresponding animal species. Due to the heavy rainfall, the surface runoff is also well developed, and the soil is latosol with strong leaching ability. In a word, the physical and geographical elements of Xishuangbanna are not simple spatial agglomeration, but interact and restrict each other, showing a high degree of unity.
Teacher: Let's look at the activities in the textbook P93. Please think:
1. What are the geographical elements in the map?
2. How does water change among various elements?
3. How is solar energy transferred between elements?
Health 1: The geographical environment elements in the map include atmosphere, water, rocks, organisms and soil.
Teacher: Yes. Then please think about it, how does water pass between these elements?
Health 2: Atmospheric precipitation keeps the soil, hydrosphere and living things supplied with water. Evaporation of water surface, evaporation of soil surface and transpiration of plants make water re-enter the atmosphere in the form of steam.
Teacher: That's good. Can you draw a schematic diagram of the transformation of water between various elements of geographical environment to make this process more intuitive and clear?
(Students draw pictures, the teacher summarizes)
Teacher: We know that the energy to maintain biological activities comes from solar energy, so how is solar energy transmitted among various elements of geographical environment?
Health 3: Plants fix solar energy through photosynthesis, and animals feed on plants directly or indirectly. After animals and plants die, the remains are decomposed by microorganisms, and energy is finally released into the environment.
Teacher: That's right. Let's also draw a schematic diagram of solar energy transmission among various elements of geographical environment.
(Students draw pictures, the teacher summarizes)
Teacher: The conversion process of solar energy among various elements of geographical environment is actually a biological cycle process. Please read P92' s Biological Cycle, and carefully observe Figure 5. 1 to find out the role of organisms in the geographical environment.
Biology is the creator of natural geographical environment.
Teacher: So, what is the most fundamental role of biology in geographical environment? Why?
(Student answers, teacher summarizes) It is the photosynthesis of plants. Because only photosynthesis can use light energy to synthesize carbon dioxide, water and inorganic salts into stored organic matter and release oxygen. Animals must eat plants directly or indirectly, and the residues of animals and plants are decomposed by microorganisms and returned to the environment in the form of inorganic substances. This is the biological cycle. It makes substances and chemical elements in the environment migrate, and energy flows and transforms in the ecosystem, thus connecting the organic world and the inorganic world in the geographical environment.
Teacher: Please draw a schematic diagram of material circulation and energy activities in the geographical environment.
Teacher: Great changes have taken place in the environment since the formation of the earth. Biology plays a very important role in the formation and evolution of the natural geographical environment. Please read the case 1 Thinking: How does biological circulation transform the atmosphere, hydrosphere and lithosphere?
(activity query)
Health: The early atmospheric composition of the earth was not dominated by nitrogen and oxygen today, but mainly carbon dioxide, carbon monoxide, methane and ammonia. At present, oxygen mainly comes from photosynthesis of plants, and some nitrogen in the atmosphere comes from biological action.
Teacher: Yes. So how do creatures transform the hydrosphere?
Health: The chemical composition of water on land is also influenced and restricted by biological cycle. In addition, organisms have a metabolic process, in which material exchange occurs constantly between organisms and geographical environment, absorbing some chemical elements and compounds from water, and discharging some chemical elements and compounds into water at the same time, thus changing the chemical composition of land water.
Teacher: Not bad. Not only that, in fact, green plants also participate in the water cycle, which also changes the water status of the landing site. Who wants to talk about how the lithosphere has been changed by biology?
Health: There are fossils in some sedimentary rocks, indicating that there are organisms involved in its formation. Coal and oil are formed by the accumulation and change of biological residues.
Teacher: Yes. There was no soil on the land, but since the appearance of life on the earth, it has accelerated the weathering of rocks and promoted the formation of soil. The formation of soil, in turn, accelerates the growth of organisms, thus making the geographical environment undergo greater biological transformation. Therefore, the appearance of life on the earth has fundamentally changed the face of the earth, and finally formed a geographical environment suitable for our human survival.
Teacher: Through the study just now, we know that the integrity of geographical environment is due to the exchange of material and energy between geographical elements. Each geographical element has its unique function, but the elements of natural geographical environment are by no means a simple collection in space. It is a harmonious system, and this system will produce some new functions that each element does not have because of the interaction of each element.
(blackboard writing) Second, the interaction between geographical elements produces new functions.
(activity query)
Teacher: Please look at the tree in Figure 5.2 and think about it. What conditions does this tree need to grow?
Health: We need sunshine, water, air and nutrition.
Teacher: Not bad. We all know that the growth of plants produces substances through photosynthesis. Can plants complete photosynthesis independently? Imagine, if we transplant this tree to the desert in western China, can it survive well in the natural state?
Health: Of course not.
Teacher: Why?
Health: lack of water.
Teacher: Then why do some plants survive well in the desert?
Health: Those plants are very drought-tolerant.
Teacher: Yes, those plants have adapted to the arid environment for a long time. So what does this mean?
Health: It shows that the way and intensity of material and energy exchange between organisms and the environment in different regions are different.
Teacher: Not bad. Obviously, plants only have the ability of photosynthesis, but they must also have external conditions to provide the corresponding material basis. For example, the atmosphere provides heat and carbon dioxide for plants, and the soil, hydrosphere and lithosphere provide water and inorganic salts for plants, so that plants can carry out normal photosynthesis and produce organic matter. Therefore, this production function of green plants is the whole function of natural geographical environment, not the function that a single geographical element can have.
Teacher: Please look at the activity of P94 and think: Why can the number of Tibetan antelopes remain relatively stable in the natural state?
Tibetan antelopes have adapted to the harsh natural environment in Hoh Xil for a long time. In the absence of human interference, the changes of various elements of the natural environment in Hoh Xil forced Tibetan antelopes to adapt to the environment by increasing or decreasing their numbers, thus keeping the number of Tibetan antelopes relatively stable.
Teacher: Yunnan golden monkey is a very rare protected animal in China, but it is reported that its number has been declining in recent years. Please think about what caused it.
Health: Because the habitat vegetation of Yunnan golden monkey has been seriously damaged, the environment has undergone fundamental changes, and they have lost their living space.
Teacher: Good. Obviously, in the absence of external factors, the number of species in a certain range can basically remain unchanged, which shows what kind of function the natural environment has?
Health: the balanced function of the natural environment.
Teacher: Yes. Obviously, this balance function is not possessed by all elements of the environment alone, but through the exchange of matter and energy, the nature of natural geographical elements remains relatively stable.
Teacher: We know, what is the reason for the global warming trend?
Health: the greenhouse effect of carbon dioxide.
Teacher: Yes. The greenhouse effect didn't exist until after the industrial revolution. Before that, we were not as worried about global warming as we are today. Although the atmosphere itself does not have the ability to slow down carbon dioxide, the carbon dioxide in the atmosphere has not increased. What plays a role in balancing the atmospheric composition?
Health: Plants consume a part of carbon dioxide through photosynthesis, and can also fix a part of carbon dioxide in the ocean under the action of organisms.
Summary: Right. However, since the industrial revolution, the amount of carbon dioxide released into the atmosphere by human beings has increased sharply, exceeding the balance capacity of nature, so this balance is in danger of being broken. Therefore, we should fully consider the natural ecological balance in our production and life, so as to coordinate environmental protection and economic development.
homework
Complete the geographic fill atlas.
5. Examples of geography teaching plans for senior three.
There is a lot of knowledge that is closely related to life in high school geography, and "Common Weather System" in the third section of Chapter 2 of "Atmosphere on Earth" is one of the most typical contents. A lot of knowledge in this section is often accessible to students in life or on TV. The weather is fine and warm, and the students are familiar with it, but they may not be able to grasp its changing law. Students are very interested in these issues, and their enthusiasm for learning is relatively high. The textbook introduces this aspect in detail. How can students better grasp the law of weather changes? In the process of thinking about how to make students better understand this part of the content, I thought of three teaching methods: First, contact life. Before class, show students a video of weather forecast that students often contact. When they see the programs they often watch, they feel very cordial and their interest in learning is immediately aroused. Moreover, the video also enriches what they have learned in this class and gives students preconceived ideas. First of all, they have a general understanding of what they have learned. With the help of students' existing knowledge, the contents of the video are stored in their brains, and then processed, analyzed and compared to form the image of new things. Doing so will get twice the result with half the effort for the next teaching.
Secondly, use multimedia animation to demonstrate the previous structure and reason diagram. Multimedia contains a lot of information, which can provide students with more pictures and animations in class. Some knowledge of this course is relatively macroscopic and abstract, and students' geographical knowledge is relatively weak in junior high school. It is difficult for students to understand the structure and changing process of the front only through written expression. By looking at the picture (front structure diagram), students can deepen their knowledge and understanding of the writing system. It helps them to establish a relatively complete knowledge system and master the spatial position, spatial structure and spatial relationship of geographical things.
Third, contact the actual situation in the region. The weather around the world has its particularity, and Xin Kegai also suggested that students should know more about the geography of their hometown, so when I put this content, I boldly added the local weather changes to explain the common weather system. There happened to be a cold air going south in the last section, which affected our city. Combined with the cold air going south this time, the weather changes before, during and after the cold front crossing the border and its influence on our city are vividly explained. Through this example, students can easily understand the knowledge of cold front.
Fourth, the method of chart combined with explanation. In view of the fact that the image system and text system in the teaching materials are what we should master. Moreover, there are three kinds of common weather systems: cold front, warm front and quasi-static front. There are similarities and differences among these three weather systems, which are easily confused by students. In order to solve this problem, I compared the top view, side view, structure, air mass movement, precipitation distribution, precipitation characteristics and weather change characteristics of three weather systems by listing. In this way, students can intuitively feel the similarities and differences of the three fronts, and it is easier to sort out the knowledge points.
However, the design of this class also has many shortcomings:
First, in grasping the time, too much time is spent on the structure and causes of the front, which makes less time spent comparing the similarities and differences of the three front systems in the following list. I haven't had time to mention the knowledge point of the influence of cold air on our city recently. Many students didn't understand this content well.
Second, when talking about the influence of frontal crossing on the weather changes in the passing area before, during and after crossing, the answers are announced to the students too early, so that the students have no time to think, their brain ability is not well mobilized, and their activities are insufficient.
Third, during class, due to multimedia errors, some animations were not displayed. Moreover, the multimedia screen is too small, so the students in front can clearly see the contents of the screen, while the students sitting at the back of the classroom can't see the contents of the screen clearly because of reflection, which affects the overall effect of the classroom. These problems were not expected before class, and I will adjust them in time in the later class.
All the cases in this lesson come from reality, which makes the teaching materials close to life and stimulates students' interest in studying natural phenomena.
In the process of case analysis, students' existing knowledge and new knowledge are called to understand the previous system and make the knowledge lively and interesting.
In the process of case analysis, the method of integrating theory with practice is adopted to promote thinking and broaden horizons, which is conducive to the cultivation and all-round development of students' comprehensive ability.
Dialectical materialism is integrated into the teaching of these cases, which enables students to establish a scientific world outlook and embodies the educational function of geography teaching.
Many phenomena and laws in nature require us to explain and study with geographical knowledge. How to make students understand this knowledge more effectively and directly is a problem that our geography teachers need to design and think carefully.