GISdevelopment.net ---> AARS ---> ACRS 1990 ---> Education/Training Teaching Remote Sensing knowledge in the middle school Fan Wenji (Lanzhou Middle School of the Chinese Academy of Sciences, Lanzhou, China) Abstract It is required to teach remote sensing knowledge in all middle schools by the commission on Geographical Education of International Geographical Union. This will strengthen the teaching material of geography and open a new road to spread remote sensing knowledge among the people. This is the first time to introduce the method of popularization of remote sensing knowledge in middle schools of China. The middle school age is the just time for the students to learn the knowledge, they will become talented in remote sensing. Because China occupies the most dominant position in the number of students all over the world, so we will have abundant reserve force for remote sensing. The article is divided into two parts: The simple satellite photograph and remote sensing knowledge recommended in junior classes. The more perplexing problems for senor classes are4 to teach weather forecast according to satellite cloud picture and the solar radiation electromagnetic spectrum. Sometimes examinations were carried out in the form of tests. The experiences were summed up and suggestions were made at the end of this paper. The significance of spreading Remote Sensing in middle schools In " Handbook for geography teaching" [1] (Compiled by Unesco, 1982) the Commission on Geographical Education of International Geographical Union required to bring about some new ideas, some new targets and geographic teaching methods to the text book. It also highly required to introduce the knowledge of remote sensing which we called "eyes in the sky" to school students.[2] Then in 1982, contents about remote sensing were brought into China's geographical textbooks for middle school students for the first time. It is a new move with some far reaching significance. First, with 60 million middle school students, China enjoys the unsurpassed predominance in the number of students in the world. The popularization of remote sensing knowledge means a large reserve of such talents and it would be no doubt a great achievement. second, these students, builders of the 21st century equipped with the technique , will be the most important generation for the human civilization. In the near future with the help of remote sensing technology, they may view the earth" in an easy manner as they look at the moon". And they are familiar With the earth as with their nearby street. Third, the students who are learning the knowledge are in their high time for learning. Their pre-available knowledge enables them to imbibe remote sensing knowledge easily. Their knowledge on remote sensing will encourage them pursue science. With the rapid development of modern science and technology, our geographical environment, today's geographical theories, geographical teaching conditions and methods and qualities of students all have changed greatly changed, especially the means of research. The means have been improved from simple-maps to aerial photographs, television, slides and even equipments with computer. In order to catch up with the development of the latest science and technology in other advanced countries, according to the content of teaching materials and groups of students divided by their ages, we carried out programme of lecturing remote-sensing knowledge among our students. We found that it has played an active role in the reform of geography teaching in middle school. Here are some intimate knowledge about our practice. Teaching Remotes Sensing knowledge in junior class A New Window on Our Planet ---------Satellite Photograph (Fig. P-1) [3] It is the panoramic view of our own planet. It ended the history in which the teacher had to prove the earth to be a global planet by describing a far-away ship seems to be a half-sunken one in the telescope" Almost every students first year will be excited when he sees the picture. Swell! This is our earth seen from a satellite or a spaceship. On this global planet are blue oceans and white clouds above. Also we can see the Arabian Peninsula, Africa, orange deserts and some tropical rain forests in olive green. "Oh, how fascinating! "A boy said excitely," I wished to be a soldier. But now I make up my mind to be an astronaut. I want to look at our earth with my own eyes from a spaceship and then take a full-view picture of our motherland. "Of course their interest in geography and remote sensing technology thus becomes stronger. Remote Sensing Knowledge Can Help Mapping Teaching Maps are the most conventional way for geography learning. The students may list many kinds of thematic maps they've even seen. After giving some basic knowledge about map or mapping, we require the students to draw a map of their most familiar street. Generally from on - the - spot investigation to drawing up, the students may spend half a day at least (see Fig. A-1). Then we bring in the information about high-speed and high-quality of remote sensing maps by raising the following questions: By on-the-spot investigation how much time we have to spend in order to investigate the 149 million km2 of the continental area and even the 510 million km2 of the global are? With their own intimate knowledge the students will become interested in remote sensing mapping ( See Fig. A-2). We can tell them: By navigators' exploration, man spent more than 1000 years to make clear the outline of the continents and oceans, 300 year map surveying can only cover 50 per cent of the continental area. Aerial photogrammetry covered more than 70 per cent of the continental area in less than 100 years. Now with the high speed of satellite remotee sensing, man may get a set of pictures on the whole surface of the earth every days. So you can see that it will be only a short time later for every corner of the earth to have its map. The students often given us some questions as follows; How can we conclude that the Amazon River is the longest one in the world, why not Nile River? Why we can see some blanks on Tibet Plateau and Antarctic in the maps? Then we bring in the knowledge on the high quality and accuracy of satellite mapping: We find the upper origin of River Amazon in the forest from the satellite pictures. Its length has been added. We can find some in habitant grass lands, lakes and glacier on Tibet Plateau. We tell the students that we can also fight against natural disaster with the help of satellite pictures. We can given them some more examples they familiar with such as , the surveying about the forest fire in Great Khingam Mountain; China's gigantic ship " Yuejin" sank near the liaoqiao Isles because of the de-estimation on ocean current of its first voyage to Japan in 1970s[4], and the well-known ship "Titanic" which sank in north Atlantic ocean on April 15, 1912. We can tell the students that these tragedies may had been avoided if they would have the help of satellite surveying. By these vivid mens, the students can not only grasp the knowledge in the textbooks but also absorb the abstract learning on remote sensing. Teaching Remote Sensing in senior class The second-year students have been equipped with some physical, mathematical and general scientific knowledge. According to their characteristics, we teach them remote sensing knowledge mainly in two ways. Solar Spectrum and Ground Radiation In China's geographical textbook for senior students the contents are concerned about what the basic knowledge of remote sensing is[5]: The sun is a huge scorching hot gaseous star. It continuously gives off energy to the universe in an electromagnetic wave form. The dominant wavelength of solar radiation ranges from 0.15 to 4 µm. The range for visible light is between 0.4 and 0.76 µm. Ultraviolet rays (wavelength less than 0.4 µm) and infrared rays ( wavelength longer than 0.76 µm) can not be seen by man's eyes. From experiments we know that for an object the higher temperature it has, the shorter wavelength it has for its strongest radiation part. For an object the lower temperature it has, the longer wavelength it has for its strongest radiation part. Solar radiation focuses on the part of visible rays which have shorter wavelength ( See Fig. A-3) Here are some relations on ground radiation. The surface temperature of the earth is much lower than that of the sun, So the wavelength of ground radiation is much longer than that of the sun. Its radiative energy focuses on the part of infrared rays. At the same time it reflectivity to solar radiation is different under the different ground conditions (Table 1). Therefore the heat received by the ground will be different and the wavelength of ground radiation will not be the same. Table 1 Reflectivity under different on ground conditions Ground Sand soil Clay Light soil Dark soil Grass Farm land New snow Ice Ocean Average equator Reflectivity % 29-35 20 22-32 10-15 26 14 84-95 50 7 2 In order to coordinate the teaching on these content we did the following work to stress remote sensing teaching: We use prism to show the seven kinds of colour in sun light and tell the students to observe carefully on rainbow and secondary rainbow. Combing with the weakening function of the atmosphere to the solar radiation, we introduce the " atmospheric window" to student , then we also introduce to some main sensors used in many kinds of remote sensing equipment (See Fig, A-4) [6]. When the students came to know that their eyes are also a kind of sensor, they show you more interest in it. (Camera, as a simple sensor, has been used more widely in geographical teaching. For example, the solar partial eclipe appeared on Sept. 23, 1987 in Lanzhou was photoed. Camera has also been used in landform study at a wide field. The Teaching about Satellite Cloud Pictures and Weather Interpreting The general circulation synoptic systems and regional weather and climate are the difficult points for teaching. Because all of these are changeable from time to time. To solve these problems we use satellite clouds. Fig. P-2[7] shows the arid winter monsoon from the continent, when the monsoon goes through the Japan Sea it carries moist air there and the coastal area will have precipitation. The photo shows clearly the laws of the monsoon rainfall. Fig. P-3 [8] shows the process of a typical tropical cyclone formation. It can be used to lead the students to an understanding of the character of cyclone, such as "when air current flows into center from all directions, the in central place will be forced up, then temperature is reduced then cloud and rain and tropical cyclone-typhoon tempests will be happened. In order to check the result of teaching, we direct the students to make a weather forecast for the following 14 cities by studying Fig. P-4, and Table 2. They are also required to reply the question about the direction and character of the summer monsoon in China. The result showed that about 22 students (81.48%) among the 27 students passed the test (see table 3). After a lot of study, observation and training, the ability of students' on forecasting by looking at satellite pictures have improved a lot. Summary and propasal on Remote-Sensing teaching in middle school. Because the teaching of remote sensing in China's middle schools started late, we still have to do more work to upgrade our teaching level. Learned from our practice, we can summarize our experiences and then put forward some proposals as follows: We enter difficult problems from simple ones and advance step by step. Remote sensing is a up-to-date technique. So it is not easy for the students to comprehend the knowledge. We'll have to start with easy ways. For example, we can introduce knowledge of sensors from human eye, camera, multi-spectral scanner and then to radar, satellite photography, side-look radar and computer mapping. Without the understanding about simple, there can't be an obtainment on perplex. Conforming to the reading of China and teaching a flexible methods. As a developing country, China can't offer so much fund for remote sensing education. We can't get enough instruments and equipments. Then we 'll have to introduce some simple of flexible ways in teaching , for example, analyse solar by observing rainbow and secondary rainbow; employing general camera to show the principle of sensors; requesting the students to watch the daily weather chart on TV. There ought to be some requirement for remote sensing in geographical syllabus of middle-school. There also should be systematic content in chapter or section in the textbooks and add some more photos (e.g. village settlements, cities, deserts, ice sheets or unmanned zone, etc) in them. Improving the means of remote sensing teaching. China has no demonstrative equipments for remote sensing teaching. City weather  City weather  Beijin rain Shengyang cloudy Tianjin drizzle Xi'an Clear Chengou rain Kunming showers Shanghai Showers Wuhan Clear hangzhou Clear Guangzhou Clear Taibei Clear Hongkong cloudy Tokyo rain Manila cloudy ( Source: China Daily, July 18, 1988) Table. 3 Teaching result ( 14 cities weather predication) All right    % 1(person)  3.7 W.1  % 4    14.8 W.2  % 4    14.8 W.3  % 3    11.1 W.4  % 5    18.5 W.5  % 2    7.4 W.6  % 3    11.1 W.* 7**  % 1    3.7 W.8  % 2    7.4 W.9  % 0    0 W.10  % 1    3.7 W.11  % 1    3.7 W.12--14  % 0            0 This blank should be filled after some relevant research work. Meanwhile the students reference books on the subject. And that would be better if we add some exhibition halls of remote sensing for the young children. Strengthening the students' abilities on remote sensing. This is necessary for China's future. We should start some research work on remote sensing technique for the young children, such as simple weather forecasting and interpreting of satellite photos, etc. And we should also encourage the students to write small academic thesis. Organizing some knowledge competions will be also much helpful. Establishing some concerning institutions and carrying out some programmes for training remote sensing teachers. Using the successful experiences of their countries for deriving and ex-changeing, we try hard to raise China's education on remote sensing to a higher standard. References Norma J. Grares, New Unesco Sources Book For Geography Teaching, Ling Man/The Unesco Press, 1982. D. Dorothy Harper , Eye In the Sky, Multiscience Publication Limited, Canada, 1979. People's Eeducation Editorial office, Geographical Textbook for Junior Middle School, People's Education Press, China, 1985, P. 19. Chen Shupen, Zhao Yinshi, Remote Sensing Information, China, No.2, 1988, P. 2-4. People's Education Editorial office Geographical Textbook for Sennior Middle School, People's Education Press, China, 1985. P. 42-75. Department of geography , Beijin University , Geological explain for ERST of photography Geological Publishing House , China, 1978, P.2. YAMAMOTO,< The Basic New - Geography>, Japen, Ninomiya Shoden, 1985, P.18. SATOO, et al. < The superior Geography>, Japan, Teekoku shoin, 1985, P.28.