Pollution of Huaihe River and Its Control

Rain and flood in Huaihe River basin in 2003! Analysis of water regime characteristics In the summer of 2003, the heavy precipitation belt lasted for a long time in the Huaihe River Basin, and the fluctuation range of the rain belt from north to south was very small.

It almost coincides with the main stream of Huaihe River, and tributaries and floods from the upper reaches converge together, plus the runoff of heavy precipitation in this area.

During the period from June 2 1 day to July 22, the total precipitation days in Huaihe River Basin generally exceeded 20 days, and the precipitation intensity was large and strong.

The precipitation is very concentrated, and the water level in the Huaihe River basin has risen in an all-round way, which led to the great flood in the Huaihe River basin in 2003. "

The direct cause of the extraordinary flood in Huaihe River Basin in summer of 2003 was the southward subtropical high in July.

Jiangnan! Over South China and the Western Pacific, this circulation situation led to a large amount of water vapor gathering in the Huaihe River Basin.

The evolution map of hPa wind field and relative humidity field can be found (omitted). There are four monsoon surges during heavy precipitation in Huaihe River Basin, which will

The water vapor from the Bay of Bengal and the South China Sea is transported northward to the Huaihe River Basin, forming a water vapor convergence center. Meanwhile, China

The cold air at high latitudes spread southward (as shown in the picture), causing heavy precipitation on the Meiyu front, indicating that the water vapor transport and the intersection of cold and warm air are plum blossoms.

Important conditions for heavy precipitation in rainy season "

Another important cause of the flood disaster in Huaihe River Basin in 2003 was the river caused by the down slope of the riverbed profile in the middle and lower reaches.

Insufficient drainage capacity "Hongze Lake bottom elevation10 ~1m, and Laozi mountain river bed at the estuary elevation is 9~ 10m, which is relatively high.

Fushan River bed is 4~5m with obvious slope. This special geographical environment has increased the flood control pressure in the Huaihe River Basin.

Force, especially in the middle reaches with flood pressure and flood jacking. At the same time, there are four flood storage areas along the Huaihe River in Anhui Province and

The long-standing problems in the flood discharge area at 17 are low flood control standards, frequent flood inflow in some flood discharge and storage areas, and poor flood discharge.

Meet the planning requirements, thus aggravating the flood disaster. "

5 conclusion theory

(1) After the Huaihe River Basin entered the flood season on June 2 1 day, there were 7 heavy precipitation processes in * * *, with stable rain belt, concentrated rainstorm and large drop.

Water processes appear one after another, which is the second rainy year after 1954. "

(2) The three flood peaks gradually decreased, and the water level oscillated between the warning water level and the guaranteed water level, resulting in floods in Bengbu and Hongze Lake.

The flow exceeds 199 1 year "

(3) In the early stage, the precipitation in Jianghuai area was obviously too high, which led to the high water level in rivers and lakes, leaving a very high bottom for the main flood season.

Water, therefore, the continuous precipitation after plum blossom, the underlying surface absorbed little, and soon formed water or runoff, leading to the surge of Huaihe River flood. "

(4) The inverse gradient of the riverbed profile in the middle and lower reaches of Huaihe River makes the discharge capacity of the river channel insufficient, which also aggravates the flood disaster.

Degree "

refer to

1 d. Study on persistent heavy rain in jianghuai basin. Beijing: Meteorological Press, 1993.

2 Zhou Zijiang, Song Lianchun, Li Xiaoquan.65438+1998 Precipitation Analysis of the Extraordinary Flood in the Yangtze River Basin. Journal of applied meteorological science, 2000, 1 1(3):287~296.

3 National Meteorological Center .. 98 Flood and Weather Forecast in China. Beijing: Meteorological Press, 1999.438+0 ~ 34.

4 Jackie Zhang, Tao Shiyan, Zhang Qingyun, et al. Meteorological and hydrological characteristics of rainstorm and flood disasters in China in summer of 65438+ 1998. Journal of applied meteorological science, 200 1, 12(4):442~

457.

5 Tao Shiyan, Ni, Zhao, et al. 198 Study on the Formation Mechanism and Forecast of Heavy Rain in China in Summer. Beijing: Meteorological Press, 200 1.

6. Bi Gui Bao. There is continuous rainstorm in the south and thunderstorm in the north. Meteorology,1998,24 (9): 58 ~ 61.

7 Taoshiyan. Rainstorm in China. Beijing: Science Press, 1980.

Feng Peizhi, Li,, et al. Analysis of main meteorological disasters in China. Beijing: Meteorological Press, 1985.29~42.

9 Zhou Xiuji, Xue Jishan, Tao Zuyu, et al .. 98 Scientific experimental study on rainstorm in South China. Beijing: Meteorological Press, 2003.3 Analysis of Hydrological Characteristics.

With the beginning of heavy precipitation in Huaihe River Basin on June 29th, the water level and discharge of Wangjiaba rose rapidly (Figure 5a), and it was 1 in July.

On July 2, the warning water level was exceeded, and Wangjiaba flooded in the early morning. On July 3rd, the first flood peak in the Huaihe River Basin passed through Wang Jia.

For the dam, the discharge reaches 5930 3s- 1, which exceeds the guaranteed water level (29m) by 0.41m "due to the weakening of precipitation from July 6 to 8.

The intensity of flood diversion increases, the water level drops slowly, and the flow decreases rapidly. "On July 9, the precipitation intensity increased, and the water level and flow rate rose again.

Rising, the second flood peak crossed Wangjiaba on July 12 (flow: 4530m3#s- 1, water level: 28.79m) "July 13~

18 precipitation weakened, water level! The rapid decline of discharge "caused the precipitation process in Huaihe River Basin on July 2, 20031~ 22.

The third flood peak "Generally speaking, the third flood peak gradually decreases, and the water level oscillates between the warning water level and the guaranteed water level"

Zhengyangguan (Figure 5b)! Bengbu (Figure 5c)! The variation range of water level and discharge in Hongze Lake (Figure 5d) is smaller than that in Wangjiaba Ⅲ.

The secondary flood peak generally shows a gradual downward trend, but the decline rate is obviously smaller than Wangjiaba, and the water level has been above the warning water level.

In fact, the first two flood peaks of Zhengyang Pass exceeded the guaranteed water level, while Bengbu and Hongze Lake did not exceed the guaranteed water level.

The flood discharge of the port and Hongze Lake exceeds199/kloc-0 once a year. "

Figure 5 Water level from June to July, 2003 (solid line)! Warning water level (solid line)! Ensure the water level (imaginary straight line)! The floods in Huaihe River basin are mainly caused by the precipitation in a large area of the basin. "This paper chose the Huaihe River Basin.

15 representative station (Henan Xihua! Zhumadian! Xinyang! Gushi, Bozhou, Anhui! Su county! Fuyang! Shouxian! Bengbu! Huoshan! close

Fat, Jiangsu Xuyi! Sheyang! Gaoyou! Dongtai), calculate its daily average precipitation, and calculate the Huaihe River Basin 1954.

June 2, 20031day to July 22, 2003.

Annual precipitation (Figure 3) "As can be seen from Figure 3,

Historically, the floods in the Huaihe River Basin correspond to this curve.

It is good, and basically reflects the characteristics of precipitation in Huaihe River basin for many years.

In 2003, the precipitation in Huaihe River Basin was obviously higher.

More than 199 1 year, more than 1954 year.

Less than 64mm, which is the second most after 1954.

Relationship between "Rainy Year" and Precipitation in Huaihe River Basin in 2003

1954! 199 1 precipitation difference chart in the same period (Figure 4)

It also illustrates the fact that 15 is selected in this paper.

This station can basically represent the precipitation in Huaihe River Basin. "

Figure 3 Huaihe River Basin 1954 ~ 2 1, June 2003

Precipitation changes on July 22.

As can be seen from figure 4b, whether from June 1 to July 22nd or from June 2 1 to July 22nd, Huai 2003.

The precipitation in the basin is more than that in the same period of 199 1 year from June to July 22nd, generally more than 50 ~ 1 00 mm, in northern Anhui.

Department! Half of Henan! In southern Shandong, it is more than 100~300mm ",but in the heavy precipitation period in 2003 (June 21~ July)

22nd), generally more than 60~200mm, in eastern Henan! 300 ~ 400 mm in northern Anhui "June ~ July 2003.

Compared with the same period 1954, the lower reaches of Huaihe River in northern Jiangsu are 50~ 100mm more than the middle and upper reaches of Huaihe River Basin.

Less than 50~200mm, even in the period of heavy precipitation (June 21~ July 22), the distribution is similar. "

Fig. 4 the relationship between the precipitation in Huaihe river basin and 1954 (a) from June to July 22, 2003,

199 1 year (b) deviation distribution chart (unit: mm) for the same period1precipitation in Huaihe river basin from June 2, 2003 to July 22, 2003 (mm)(a)

And the percentage of precipitation anomaly (%)(b) (relative to the average value of 197 1~2000).

The warm and humid airflow on the north side frequently confronts the Huaihe River basin, resulting in June 22~23! 24~27! 29-3 July

Fuck! 4~7 days! 8~ 1 1 day! 12~ 13! 2 1~22 ***7 rainstorm weather process "7 rainstorm process rainfall.

The temporal and spatial distribution of is as follows:

(1) June 22~23, affected by the northward uplift of subtropical high and the low-level shear line, south-central Shandong! Henan Province

Most! Most of Anhui! Su Su Su Bei! There was a rainstorm in eastern Hubei, and the rain belt was northeast) southwest, with

The three heavy precipitation centers are all in Macheng, Hubei! The precipitation near Shangqiu in Henan and Yinan in Shandong is generally 50~ 100.

Mm, in which the precipitation in Dabie Mountain area in eastern Hubei, eastern and southern Henan and southern Shandong reaches110 ~190mm.

(Figure 2a) "Heavy precipitation mainly occurred on 23rd, and the number of stations with daily precipitation exceeding 100mm reached 49, with daily precipitation exceeding.

There are five 150mm, and the maximum precipitation occurs in eastern Hubei. "This is the first time in the Meiyu period of the Huaihe River Basin in 2003.

Heavy precipitation process "

(2) On June 24-27, the main rain belt pressed from the south to the north of the south of the Yangtze River, but the Huaihe River Basin was affected by supplementary cold air, resulting in a catastrophic flood in 2003! Hydrological characteristics analysis

Bi Guibao Jiao Meiyan Liao Yao Ming Xu Jing

(National Meteorological Center, Beijing 10008 1)

abstract

Based on the ground encrypted data, the temporal and spatial distribution and climate statistical characteristics of precipitation in Huaihe River basin from June to July 2003 were analyzed.

And precipitation and rain! Characteristics of water regime, and compared with the same period of history ". The results show that the Meiyu period in Huaihe River basin in 2003

After seven times of heavy precipitation, the total precipitation and flood flow exceeded the same period of 199 1 year, but both were lower than the meiyu period of 1954.

The outstanding characteristics of precipitation in Huaihe River basin in 2003 are: stable rain belt! The rainstorm is concentrated and sudden; The characteristics of water regime are as follows: flood peak chasing.

Sub-decreasing; The main reasons for exceeding the warning water level in Huaihe River Basin are: too much precipitation in spring of 2003! Subtropical in July

The high pressure is located to the south, and the riverbed profile in the middle and lower reaches of Huaihe River moves down. "

Keywords:: Huaihe River Basin precipitation peak water level

cite

Since the 1990s, there have been many floods in Huaihe River Basin "199 1 year only in Anhui! Jiangsu province was affected by this disaster.

The population reached 7 1%, the area affected by crops accounted for 60%, and the direct economic loss reached 45 billion RMB. 1999 southern Anhui! The abbreviation of Suzhou/Jiangsu Province/Soviet Union/a surname

Northern Jiangsu and southern Jiangsu suffered the biggest floods in 50 years; From late June to mid-July, 2003, a torrential rain occurred in Huaihe River Basin.

This rainfall, with its large rainfall, long duration and wide range of influence, is rare in history, and the rainfall and water conditions in Huaihe River Basin are all over.

Over 199 1 year "In recent years, many meteorologists have paid attention to 199 1 and 1998 Jianghuai rainstorm [1~8]! 1998 torrential rain in south China

Rain [9] and other processes and causes are analyzed and studied, which lays the foundation for the study of large-scale heavy rain.

Encrypted data of flood and rain in Huaihe River Basin in 2003! The characteristics of water regime are analyzed in detail. "

Distribution characteristics of 1 precipitation in Huaihe river basin in 2003

On June 2, 20031day, the main precipitation belt in China came from South China! South of the Yangtze River jumps north to the Huaihe River Basin, and in this area,

After the Huaihe River Basin entered the flood season on June 2 1 day, it lasted for 30 days, and there were 7 heavy precipitation processes, with average total precipitation.

It is 200~500mm (figure 1a), including northern Anhui! 500~700mm in north-central Jiangsu "Northern Anhui! He 'nan East

South! The total precipitation in northern Jiangsu and other places is generally more than normal 1 ~ 2 times, and it is more than 2~3 times in some areas (figure 1b). "

From June 2, 2003 to July 22, 2003 (omitted), the average height field of 500hPa can be found that the middle and high latitudes in Europe and Asia

In a situation of two grooves and one ridge. "There is constant cold air in the European trough passing through Lake Balkhash from the bottom of the resistance! Upper Yellow River and Qinghai-Tibet Plateau