Coastal distribution has the island, hainan and chongming island and south sea islands archipelago, and so on, more than 5000 large and small islands. With our country facing each other across the sea of neighbors: South Korea, Japan, the Philippines, Malaysia, brunei and Indonesia six countries. Our country complex and varied terrain, plain, plateau, hills, mountains and basin five terrain are complete, the mountainous area, accounts for about two-thirds of the national area; Relief west and lower in the east, in roughly three ladder shape distribution. In the southwest of the qinghai-tibet plateau, an average elevation 4000 meters above the, is the first step. The taihang mountains a wushan a family a geological and a line with the first steps for west between secondary ladder, altitude 1000 m in a 2000 meters between, mainly for the plateau and basin. The second step edom, and the land above sea level surface for the third grade ladder, height more than 500 m below, mainly for the hills and plains. The complex and varied terrain, and formed the complex and varied climate; Our country is the west and lower in the east, topography, the characteristics of the distribution of the ladder, moist air to further inland, supply many lunt; The river flows east to roll, communication things traffic; The river by the high level 1 ladder into the low level of the ladder of location, fast water, the enormous water. China is a monsoon climate region, winter and summer air temperature distribution difference is very big. The temperature distribution features: winter generally very low temperature, south north cold heat, the south and the temperature, temperature difference almost 50 ℃. The main reason is that: winter in the sun the southern hemisphere, the northern hemisphere get the sun energy less; Latitude effect: winter in the winter wind. Summer in most parts of the country generally high temperature (except the qinghai-tibet plateau outside), north and south is temperature difference. The main reason is that: the summer in the sun the northern hemisphere, the northern hemisphere get more calories than; In summer the summer monsoon, in most regions of China to the highest temperature rise; The summer the height of the sun, the higher the latitude, the day time to grow more, slow down the warmth of the sun the difference of accept. Winter is the coldest place MoHe town, summer is the hottest place where turpan, chongqing, wuhan, nanjing, nanchang in so-called "four stove".