Global warming and sea level rise have become an indisputable fact and a key issue of concern to the world. It’s just that for many people, they don’t know where the small coastal countries with low terrain and the "pocket" island countries in the Pacific Ocean will go when the glaciers and snow on the polar regions and other high mountains and plateaus have all melted.
Scientific research shows that the polar regions on the earth, especially the Antarctic continent, are covered by ice with a total area of 13.9601 million square kilometers and an average thickness of 2,300 meters. The total volume of ice and snow exceeds 28 million cubic kilometers. Meters, if all these ice layers melt, the global average sea level will rise by 66 meters, and most of the world’s coastal areas will be submerged by sea water.
However, with global warming, the melting of snow and ice will not only occur in the Antarctic region. In addition, the ice and snow distributed in the Arctic region and the high plateaus of , Qinghai-Tibet Plateau and other plateau mountains have all melted, and the global sea level may eventually rise by 70 Meters, this value is close to that published on the website of the United States Geological Survey ("USGS").
Children who have studied geography should be well aware that our country’s topography is diverse, although there are mountains ( at an altitude of more than 500 meters and very undulating highlands), hills ( at an altitude of 200 meters) -500 meters between ), plains (generally less than 200 meters above sea level), plateaus ( is a relatively complete large area of highlands above 500 meters above sea level), basins ( basins sometimes include plains, for example, called The Chengdu Plain, which is the "West Sichuan Bazi", is located in the five topography of the western Sichuan Basin, but the mountain area is larger, accounting for about 2/3 of the total land area of the country, and the total terrain is high in the west and low in the east.It presents the characteristics of a stepped distribution. Therefore, except for the southwest, northeast, and northwest inland areas, all major rivers (the Yangtze River, the Yellow River, the Pearl River, etc.) basically flow from west to east in China.
However, it is not difficult to find out that the first step of is Qinghai-Tibet area (near the Qinghai-Tibet Plateau and the Qaidam Basin) at an altitude of 4000 meters above sea level; the second step of is the second step of . strong18strong is mainly distributed in Junggar Basin, Tarim Basin, Inner Mongolia Plateau, , Loess Plateau, Sichuan Basin, Yunnan-Guizhou Plateau with an average elevation of 1000~2000 meters; Plains: Northeast Plain, North China Plain, Middle and Lower Yangtze Plain; Strong17strong Third Step Most of them are composed of plains with an average elevation of 200 meters or less and hills of 500 meters or less, such as the Northeast Plain, Huanghuaihai Plain, the Middle and Lower Yangtze Plain, and the Liaodong hills, Shandong hills, Southeast hills, etc.
China Sky Eye (FAST)
For my country, global sea level rise does not pose a direct threat to my country’s relatively higher first and second steps, but it poses a large area on the third step. For the low-altitude plains and low-mountainous hilly areas of China, it means being submerged under the sea.
my country’s 18,000-kilometer coastline is located on the third step, and there are 14 coastal provincial administrative units on the east coast of my country, namely: "North China Gateway" Tianjin City, "Yanzhao Woye" Hebei Province, "Liaohai Powerful Land" Liaoning Province, "Qilu Land" Shandong Province, "Rich Water Village" Jiangsu Province, "Oriental Pearl" Shanghai, "Qiantang Riverside" Zhejiang Province, "Southeast Overseas Chinese Hometown" Fujian Province, "Motherland Treasure Island" "Taiwan Province, "Lingnan Hot Land" Guangdong Province, "Prosperous Metropolis" Hong Kong Special Administrative Region, "Sea Garden" Macau Special Administrative Region, "Splendid Zhuang Township" Guangxi Zhuang Autonomous Region, "Tropical Orchard" Hainan Province.
As my country is adjacent to the Pacific Ocean, the largest ocean in the world to the east, the sea level rise caused by global warming has a very serious impact on my country, because the eastern coast of my country is the most densely populated and economically developed land , It's scary to think carefully.
However, among the 14 coastal provinces in my country, there are some provincial administrative regions with relatively small undulations and relatively low terrain. Hebei, Shandong, Jiangsu, and Zhejiang are the more typical provinces. One of them is Which province will be the lowest in our country?
Hebei Province
Hebei Province spans the two major regions of North China and Northeast China and the two major water systems of Haihe, and Luanhe. It is the only water system in my country that has both plateaus, mountains, hills, plains, basins, lakes and seashores. The province has a total area of 188,800 square kilometers. Although the Hebei Plain is part of the North China Plain , this does not mean that the elevation of Hebei Province is very low.
Jinshanling Great Wall, Hebei
In fact, Hebei has a complex and diverse topography. Not only five types of topography are complete, mainly including , Yanshan and Taihang Mountain, which are more than 50 meters above sea level, below 2000 meters. The Hebei Plain and the Bashang Plateau (part of the Mongolian Plateau) with an average elevation of 1200-1500 meters are composed of three major geomorphic units, accounting for 48.1%, 43.4%, and 8.5% of the province’s area, with an average elevation of 1,500 meters.
Shandong Province
Shandong Province is backed by the North China Plain, the most populous plain in China, with , Taishan Mountain and the Yellow River, bordering the east by the sea, and bordering Hebei, Henan, Anhui, and Jiangsu, with a total area of 157,900 square meters Kilometers are the only two provinces in my country with a permanent population of over 100 million.The total number exceeds 100.7 million, second only to Guangdong Province.
I believe many people remember that when my country and Nepal jointly measured the height of Mount Everest last year, the origin of the “height” level of Mount Everest was at the Qingdao tide gauge station on the shore of the Yellow Sea. As the national elevation datum, the sea level of Qingdao is "zero". Therefore, the terrain and altitude on the map of my country are measured and determined with Qingdao’s sea level (datum) as the origin of the coordinates.
In fact, excluding Qingdao's "zero-elevation" city, Shandong's average altitude is still very high. From the topographical point of view, the central part of Shandong is the protruding Taishan-Yimeng mountain, the east is the hills of Shandong with slow undulations, and the northwest and southwest are relatively low-lying and flat, forming a wide and staggered plain area with mountainous hills as the skeleton. The topography in between.
The elevation of the Yellow River Delta in Shandong is generally below 10 meters, which is the lowest land in the province, but the average elevation of other places is relatively high. The author calculated the average altitude of 16 prefecture-level cities in Shandong: Jinan 57.8 meters, Binzhou 11.4 meters, Dongying 8.8 meters, Dezhou 22.7 meters, Liaocheng 34.0 meters, Jining 45.2 meters, Heze 50.8 meters, Zaozhuang 74.8 meters Meters, Linyi 86.5 meters, Tai'an 134.0 meters, Zibo 34.5 meters, Weifang 19.3 meters, sunshine 22.8 meters, Qingdao 77.2 meters, Yantai 47.8 meters, Weihai 61.3 meters, about 49.31 meters after being averaged.
Jiangsu Province
Jiangsu Province is located in the lower reaches of the Yangtze River and Huai River in my country, bordering the Yellow Sea in the east, Anhui Province in the west, Shanghai and Zhejiang Province in the southeast, and Shandong Province in the north, with a total area of 107,200 square kilometers. As one of our country’s smaller provinces, Jiangsu is truly the "Su Daqiang" who is truly enviable by others.Not only has the GDP reached the 10 trillion mark to catch up with Guangdong, but it is also the province with the highest level of comprehensive development in my country. The 13 prefecture-level cities are all powerful.
Because Jiangsu's Binjiang River is adjacent to the sea, the terrain is dominated by plains. Subei Plain, Huanghuai Plain, Jianghuai Plain, Binhai Plain, Yangtze River Delta Plain, the sum of the five regional plains accounted for the total area of Jiangsu 86.89%, most of the area is below 50 meters above sea level.
The low mountains and hills are mainly concentrated in the southwest, which is the area west of the connection between Tianchang City and Taihu Lake in Anhui. There are mainly Laoshan Mountains, Yuntai Mountains, Ningzhen Mountains, Maoshan Mountains, Yili Mountains and other lower elevations. Mountains. Even the Yunv Peak in the Huaguoshan Scenic Area of Yuntai Mountain in Lianyungang, the highest elevation in Jiangsu, is only 625 meters long. A mountain of this level is at best a higher mound in other places.
Take Jiangsu's largest prefecture-level Yancheng as an example. The whole area is plain and consists of three parts: Huanghuai Plain, Lixiahe Plain and Binhai Plain, most of them The altitude of the area is less than 5 meters, even the maximum relative height difference is less than 8 meters, not even the height of a four-story building.
It is precisely because of the low and flat terrain of Yancheng that the Subei Irrigation General Canal that passes through Yancheng can be surprisingly "parallel" with Huaihe into the sea. Moreover, in history, the Huai River was repeatedly invaded by the Yellow River, causing the water system to lose its estuary into the sea and become a tributary of the Yangtze River. Jiangsu's low terrain is an important reason.
Zhejiang Province
Zhejiang Province is located on the southeast coast of my country and the southern wing of the Yangtze River Delta. It is mainly composed of plains, hills, basins, mountains, and islands. The total area is 105,500 square kilometers, which is the same area. One of the smaller provinces, slightly smaller than Jiangsu Province,GDP ranks 4th among all provinces in my country, second only to the three provinces of Guangdong, Jiangsu and Shandong.
Judging from the topography, the topography of Zhejiang is sloping from the southwest to the northeast. This can be seen from the flow of the Qiantang River and its tributaries, the largest river in Zhejiang.
Zhejiang can basically be divided into seven terrain areas: , northern Zhejiang plain, eastern Zhejiang hills, southeast coastal plain, coastal islands, western Zhejiang hills, central Jinqu Basin, southern Zhejiang mountain Among them, hills and mountains accounted for 74.63%, plains accounted for 20.32%, rivers and lakes 5.05%. It can be said that the altitude is relatively low except for the plains in northern Zhejiang, the southeast coastal plain, near the shoreline of the island, and river valleys, especially in Ningbo. The average elevation is only 4.7 meters, and the average elevation of Hangzhou is only single digits. However, the hills and mountains in the east, central and west are generally higher in elevation, and the average elevation is basically around 200 meters.
Summary
Jiangsu Province is the province with the lowest average elevation in my country. With its good location advantages and relatively low terrain, Jiangsu’s "Thirteenth Taibao" cities have been well planned. Although the total GDP of Jiangsu is second only to Guangdong, the average development level of each region far exceeds that of Guangdong, especially Suzhou, Nanjing, and Wuxi have become my country's outstanding "new first-tier cities".
However, global warming is happening. Scientific research shows that since the medieval warm period of the 11th century, sea level has been rising at a rate of 0.6 mm/year, but after the end of the first industrial revolution, sea level has risen by more than 2 mm per year . A research team from the University of Texas in the United States analyzed the changes in sea level during the seven years from 2005 to 2011 through satellite remote sensing data, and found that the average annual increase was more than 2.39 millimeters.
According to the forecast of the United Nations Intergovernmental Panel on Climate Change (IPCC),According to the current global warming trend, sea level may rise by more than 1.2 meters by the end of this century, and sea level may rise by more than 3.5 meters by the end of the next century. By that time, in less than 200 years, Jiangsu will include Yancheng. Many places inside will be submerged by sea water.
Global warming may only flood the relatively low-lying areas of the eastern coast for our country, but it will be a disaster for countries with lower elevations like the Netherlands or many island countries in the Pacific.
So we have to protect the earth environment on which we live.
.
