东洞庭湖湖陆风特征分析
Analysis of Land-lake Breeze Characteristics of the East Dongting Lake
中文摘要：
采用岳阳国家气候观象台（简称岳阳站）资料分析东洞庭湖的湖陆风日变化和季节变化特征，结合临湘与华容国家气象站、区域自动气象站资料分析2017年8月4—23日湖区气温、湖陆风、相对湿度的时空四维变化特征，结果表明：岳阳站湖陆风昼夜交替，夏季最强、冬季最弱；湖风强弱主要与南、北风频率相关，城市热岛强弱主要和湖、陆风相关。湖（水）面反光增温效应使湖区一定时空内气温升，湖面上空气温在中午前后随高度降幅大，夜晚逆温明显；岳阳城市热岛效应明显，以傍晚前后最为突出。受东部丘陵山脉大地形影响，夏季东洞庭湖东北部出现明显的实际湖陆风，西南部主要表现为风速大小的日周期性变化，湖陆风与城市热岛、山谷风存在叠加效应，近距离水体、山丘、建筑物、树木植被等对测站风、气温与湿度等作用明显；实际湖陆风随高度先增大后减小，200 m高度仍存在明显的湖陆风。湖心相对湿度随高度递减明显，湖陆风使岳阳站空气湿度变化显著。
中文关键词：
东洞庭湖，湖陆风，湖心，湖面反光增温效应，城市热岛效应，时空四维特征
KeyWords：
East Dongting Lake, lake-land breeze, lake center, lake surface reflective warming effect, urban heat island, fourdimensional characteristics of time and space
Abstract：
Based on the data of Yueyang National Climate Observatory, the diurnal and seasonal variations of land and lake winds along the east coast of East Dongting Lake from June 2017 to May 2019 were analyzed. Based on the data of Linxiang, Huarong national meteorological station, regional meteorological station, the temporal and spatial four-dimensional variation characteristics of temperature, land-lake breeze and relative humidity in Dongting Lake from 4 to 23 August 2017 were analyzed. The results show that: the lake-land breeze at Yueyang Station alternates day and night, with the strongest in summer and the weakest in winter. The lake wind is positively correlated with the warm and wet air currents , while the urban heat island is positively correlated with the land-lake breeze. Reflecting sunlight from the lake surface causes the air to warm up in a certain area near the lake. In the daytime, especially at noon, the lake surface temperature decreases greatly with the altitude. At night, the inversion layer appears. Yueyang urban heat island effect is obvious, especially around the evening. There are obvious actual lake-land breezes in the northeast and diurnal periodic variations of wind speed in the southwest. There is a superposition effect between lake-land breeze and urban heat island and valley breeze. Close water, hills, buildings, trees and vegetation have obvious effects on wind, temperature and humidity of the station. The actual lake-land breeze increases first and then decreases with the height, and obvious lake-land breeze still exists at the height of 200 m. The relative humidity of the lake center decreases obviously with altitude. The Lake breeze makes the air humidity of Yueyang station increase significantly, and the urban land breeze makes the lake center humidity decrease significantly.