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The Huang He and flooding More than 100 million people live along the banks of the Huang He. In some places the water level of the river is higher than the land. People have built dykes (mounds of earth) to try and stop the river from flooding. The river is often called "China's sorrow" because millions of people have been killed by flooding. In September 1887 the Huang He river burst its banks and destroyed 1500 towns and villages. One million people died. The flood was caused by weeks of heavy rain
The Yellow River, which runs through the Loess Plateau, carries about 1.6 billion tons of mud and silt a year. The second longest river in China and the muddiest in the world has a 37-kg silt content in every cubic meter of water. The figure rises to 300-500kg after heavy rain. The 5,464-km-long river irrigates 20 million hectares of arable land and feeds more than 100 million people in northwest and north China. The worst flood disaster in world history occurred in August, 1931 along the Huang He River in China and killed an estimated 3.7 million people. The world’s death toll from floods between 1966 and 1990 was 117,000 – an average of 4,680 persons per year (Lawford, et al., 1995).
The Yellow (Huang He) River is the second longest river in China. It has a total length of 5,464 kilometers. It is called the Yellow River because of its characteristic yellow muddy color. What is more important is that until now the River has been advancing into the sea by creating new lands in 2-3 thousand meters per year.
http://aapg.confex.com/aapg/hu2002/techprogram/paper_25681.htm Changes in the Yellow River Delta, 1989-2000 Cynthia A Evans, Earth & Imaging Sciences Lab, Lockheed-Martin Space Operations, NASA Johnson Space Center, Mail Code C23, 2400 NASA Rd 1, Houston, TX 77586, phone: 281-483-0519, fax: 281-483-2911, cevans1@ems.jsc.nasa.gov, Michael T Lee, Hernandez Engineering, NASA Johnson Space Center, Houston, TX, and Julie A Robinson, Lockheed-Martin Space Operations, NASA Johnson Space Center, Houston, TX. China’s Yellow River Delta is one of the fastest changing coastlines on Earth. Two factors contribute to the changes: 1) the river carries a heavy sediment load, leading to clogged channels and frequent river course changes; 2) the river is heavily engineered and water is oversubscribed, resulting in little flow to the coast in recent years. Dramatic changes in the tip of the Yellow River delta were documented by astronauts on the Space Shuttle between 1989 and 2000. Over this time, several hundred square kilometers accreted and eroded from the coast. The delta grew nearly 400 km2 between 1989 and 1995, then began eroding back. Between 1995 and 1997, the delta area eroded back about 255 km2. In 1997 a new channel was cut near the tip of the delta. From 1997 to February 2000, the delta tip again grew nearly 100 km2. Using the Yellow River delta as an example, we will discuss how remote sensing and image analysis of astronaut photographs are efficient strategies for examining regional changes like coastline evolution. Photographs collected by astronauts were assembled in a time series of images demonstrating both the scale and specific locations of coastal change. The images were referenced to standard maps, allowing for quantitative measurements of changes. Documentation of delta changes will continue from the International Space Station. We are targeting several rapidly changing coastlines in southeast Asia, including the Yellow River Delta.
Z.S. Yang, J.D. Milliman, J.Galler, J.P. Liu, and X.G. Sun, 1998. Yellow River's Water and Sediment Discharge Decreasing Steadily, EOS, Vol.79, No. 48. (SEE HARD COPY).
STS079-784-035 Yellow River Mouth, China September 1996 Considered to be one of the most silt-laden rivers in the world, the mouth of the Yellow River can be seen in this southwest-looking view. The Yellow River discharges over one billon tons of sediment each year into the Gulf of Bohai (bottom portion of the image). The delta of the Yellow River is being extended into the gulf steadily at a rate of one mile (1.6 km) a year, adding roughly 14 sq. miles (40 sq. km) of land in the process. The river rises in the Kunlun Mountains of western China and flows generally eastward 3000 miles (4830 km) before emptying into the Gulf of Bohai. The Yellow River is the second longest river in China and one of the longest rivers in the world. The river’s middle course is considered to be where Chinese civilization had its beginnings. The delta is used extensively for agriculture. Near the center of the image, the small commercial city of Dongying is discernible. To the east (left) of the city is the Shengli Oilfield, the second largest oilfield in China. |
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