一、概况河北平原地区包括京津以南地区及冀东平原区,总面积73,000多平方公里,地势平坦,地形由西北、西、西南向渤海方向微倾斜。本区属大陆性半干旱季风气候,春旱秋涝,年降雨量平均500多毫米,冀东平原600—700毫米,七、八两月降雨量约占全年的70%。水面蒸发多年平均达1,100—1,800毫米,高者达2,000毫米。 I. Overview Hebei Plain includes the areas south of Beijing and Tianjin and the Jidong Plain, with a total area of ​​over 73,000 square kilometers. The terrain is flat and the topography is slightly inclined toward the Bohai Sea from northwest, west and southwest. The area belongs to the continental semi-arid monsoon climate. In the spring and autumn, the average annual rainfall is over 500 mm and the Jidong Plain is 600-700 mm. The rainfall in July and August is about 70% of the whole year. Surface evaporation has averaged 1,100-1,800 mm on average for many years and up to 2,000 mm on the water surface.