What are the geographical and climatic conditions and traffic conditions in Africa? thank

Africa has three main climatic characteristics:

First, fuck. Africa's dry climate zone accounts for about 1/3 of the whole continent. Sahara desert is the most vast desert in the world, with a total area of over 900× 104km2. In addition, there are some unconnected smaller deserts in East Africa and South Africa. Most of the annual rainfall in these areas is below 100mm, and there is no rain in some areas for several years. The air humidity is low, and there are few clouds. Clear skies in Wan Li are almost common and frequent.

The root cause of this situation is geographical location. The African continent is located in the low latitudes on both sides of the equator, and the Tropic of Cancer crosses the south and north of the continent, which is a unique condition that distinguishes the African continent from other continents, so it is influenced by the subtropical downward flow in a very wide range; The fact that the Sahara Desert in North Africa and kalahari desert in South Africa respectively cross two tropic lines is evidence of this causal relationship.

At the same time, the northeast of the African continent is close to the dry area of the Asian continent, and the northeast wind blowing through that area is dry, which can only strengthen but not reduce the dryness in northern Africa. Therefore, the northeast of Africa, even the areas near the Red Sea and the eastern Mediterranean, are desert areas. This makes the Sahara desert unique in the world, stretching from east to west in Wan Li and reaching the sea on almost three sides.

Corresponding to the Sahara Desert is kalahari desert. Because the latitude of southern Africa is narrower than that of northern Africa, kalahari desert is smaller than the Sahara desert. However, the former is located in the west of the mainland, and the eastern edge of the desert is about 1000km away from the eastern coast of the mainland, which is quite different from the latter's direct access to the Red Sea. This is obviously because the southeast of southern Africa is not connected with the dry continent. If Gondwana was not divided, the scope of kalahari desert would be much larger than it is now.

Second, warm. The climate in most parts of Africa is warm in winter and hot in summer. Frost and snow can only be seen in a small area on the northern edge and southern end of the mainland, and there is permanent snow on the top of the mountain; However, the scope of these areas is extremely small, and the total area is less than 5% of the whole continent. The root cause is geographical location. The African continent is located between 37 degrees north latitude and 35 degrees south latitude. The sun is high and the ground receives a lot of radiation. At the same time, the drying area is wide and the air transmission coefficient is high, which is helpful for the ground to absorb heat and raise temperature. In addition, quite a few areas are in the leeward position, and the foehn effect strengthens the high temperature. Therefore, the values of average temperature and extreme temperature exceed those of other continents. The average temperature in the hottest month in the western Sahara desert and the lowlands along the Red Sea and Gulf of Aden is above 30℃. Extreme temperatures in large lowlands of the Sahara desert often exceed 50℃.

Third, the climate zone corresponds to the north and south. If the equator is taken as the central axis, the climate zone in Africa is generally south and north, and the equatorial climate zone gradually becomes a tropical climate zone and a subtropical climate zone respectively. The fundamental reason for this phenomenon is geographical location and scope, because the equator passes through the middle of the African continent, while the latitudes at the north and south ends do not enter the temperate zone. At the same time, the topography of the African continent is a gently undulating medium-low plateau, with little difference in elevation between regions, and the range of higher plateaus and mountains is very small, so the horizontal zonality of climate can be quite obvious.

Traffic: The natural barrier road is evil and long. It is a long road, Africa Road. The road to Africa is more arduous, longer and more sinister. No matter the road through desert, forest, canyon, grassland and swamp, it is difficult and dangerous. Many of them are not paved with asphalt, they are products of colonial times and have fallen apart so far. There is a Pan-American highway in the United States, which could have driven from Canada to Brazil. Africa is not short of coffee? Rudder rudder rudder rudder? Cross-border roads from east to west and from north to south. Even a country lacks a perfect transportation network and even basic road facilities? BR> The similar highway system is the Mediterranean coast in North Africa, followed by the international network in the Gulf of Guinea in West Africa. Railways are the main means of transportation in South Africa and East Africa. In terms of scale, South Africa's railways and highways are second to none, reaching the world level. In Africa as a whole, Central Africa, where the equatorial tropical rain forest is located, is the worst, and the land traffic in Zaire is obvious. In the rainy season, cars are often stuck in the virgin forest for a month or two. Muddy roads, flooded rivers, fast-flowing water and dangerous situations are not enough to describe the actual situation. Pig Cage Cars Walking in Cities African cities generally have public transport services. Public buses and private minibuses are full of style, and they are all overloaded. They are nicknamed "pig cage cars" by local overseas Chinese. Just like other vehicles, the maintenance of parts of "pig cage car" has become a big problem. The machine is broken, the tire is bald, and the driver is braver. Whether they bend straight or not, come on in high gear, throw a tangent, the car will turn over and people will die. Experience people's livelihood by train If you choose a train, except for a few advanced countries that serve better, they are generally hard seats, and there are no seats at any time. The carriage is shabby, crowded, stuffy and noisy, so you can foresee that you will be delayed. Even the well-known Tanzania-Zambia Railway has problems in its management and service. It is relatively safe to take the train, which is a good opportunity to understand people's livelihood and watch their lives. Besides motor vehicles, camels, horseback riding, donkey riding and walking are still very popular in Africa. Camels walking in desert and semi-desert areas are guaranteed to be unforgettable. The brilliant achievements of African blacks born and bred in track and field are not only related to their tall physique, but also related to their taking thousands of steps every day. In fact, in remote and backward areas, locals are free to walk 40 kilometers a day. Canoes with freedom of movement are in the equatorial region of Africa, with narrow rivers, shallow rapids and criss-crossing, and motor wheels are not suitable for navigation, while light and flexible canoes can walk freely. Walking in Africa, it is recommended to take a canoe or Arabian sail. Why don't we try the two and compare them to see who is more interesting?