Abstract:

Based on meteorological elements data of twelve years from Tazhong meteorological station，the characteristic of wind，temperature， humidity and air pressure in Tazhong was analyzed． The results show that there is distinctive climate characteristics of temperate zone inland desert，the temperature annual range is large with maximum of 38 ℃，and temperature daily range is also large，but air humidity is small．The wind speed is more than 2． 0 m/s from March to September but less than 2． 0 m/s in winter． Diurnal variation of air pressure is biggest in spring and least in winter．The temperature at night is low and high in the afternoon． Relative humidity at night is higher than that in daytime in each season，and in winter it can be 60% ～ 70%．All meteorological elements are similar in typical clear or cloudy days，but significantly different during the sand and dust weather processes．The air pressure is reduced by about 10 hPa under dust weather condition and rises rapidly during the dust storm weather processes．The temperature at night is significantly higher under blowing sand and dust storm weather condition than that on the typical sunny day． The relative humidity under the blowing sand and dust storm condition is similar to a typical sunny day． The wind speed is 9． 7 m/s during the dust storm process and the daily average wind speed is 6． 2 m/s on that day，but under the other weather conditions，wind speed is smaller at night that that in daytime． Diurnal variation of each meteorological element on the ground is significant throughout a year，the diurnal variation of air pressure is within 3 hPa almost everyday，the temperature daily range is up to 16． 2 ℃，the relative humidity at night is about 23% to 51% and 25% during daytime．The surface wind speed is 1． 5 m/s at night and 3． 2 m/s from 16: 00 to18: 00．

Key words: Tazhong, meteorological elements, variation, characteristics

摘要：

利用塔中气象站12 a 的气象要素数据，分析了塔中主要气象要素风、温度、湿度、气压等的变化特征。结果显示，塔中气温年较差、日较差很大，年较差达38 ℃，空气湿度很小。夜间温度低，日出后气温上升迅速，午后气温最高; 3 ～ 9 月地面风速＞ 2． 0 m/s，冬季多在2 m/s 以下。气压日变幅春＞ 夏＞ 秋＞ 冬; 各季相对湿度夜间＞ 白天，冬季可达60% ～ 70%; 地面风速与大气稳定度有关且夜间＜ 白天。沙尘时气压降低约10 hPa 且波动大，沙尘暴时气压上升迅速; 扬沙、沙尘暴天气夜间气温明显高于典型晴天，相对湿度夜间＞ 白天，扬沙和沙尘暴时与典型晴天昼间相对湿度相近，夜间多波动且数值要小; 沙尘暴发生风速最大可达9． 7 m/s，该日平均风速为6． 2 m/s，其它天气夜间风速小于白天。全年地面气象要素的日变化显著，气压日内变化在3 hPa 以内，气温日较差可达16． 2 ℃，夜间相对湿度约23% ～51%，白天相对湿度约25%; 夜间地面风速维持在1． 5 m/s， 16 ～ 18 时风速达3． 2 m/s。

关键词: 塔中, 气象要素, 变化, 特征