摘要
利用在青藏高原东南缘云南大理点苍山-洱海间不同海拔高度设立的自动气象观测站资料,分析了2012年1月1日—2014月12月31日的风向、风速、气温、相对湿度和气压等气象要素的立体变化特征,得出:1)不同海拔高度风速日变化均呈单峰型分布,海拔高度及地形对风速影响较大,海拔2640.0 m位于东西风局地环流高度位置。海拔1990.5~2640.0 m都存在东西风、南北风转化的日变化。2)气温日变化是单峰型分布,最小值出现在日出后,最大值出现在午后至日落前。3)相对湿度日变化是单峰型分布,海拔3520.0 m及以上的相对湿度最大值出现在22:00,最小值出现在11:00,而海拔1975.4~2640.0 m最大值出现在07:00-08:00,最小值出在15:00-17:00。4)气压日变化为双峰双谷型,第一个峰值出现在中午前,第二个峰值出现在午夜;第一个谷值出现在日出前,第二个谷值出现在日落。探讨了云南大理点苍山-洱海不同海拔高度气象要素日变化特殊分布是由于地形环境、水陆分布以及太阳辐射分布差异造成的,为今后研究高原复杂下垫面的大气结构、地气交换及局地环流时空变化特征提供重要依据。
Based on observational data at 6 automatic meteorological stations which were set up between Cangshan Mountains and Erhai Lake area in the southeastern margin of Tibetan Plateau, three dimensional variation characteristics of wind speed, wind direction, air temperature, relative humidity and atmospheric pressure were analyzed for the period from January 2012 to December 2014. The results show as follows： 1） The diurnal variation of wind speed at different elevations displayed as one peak, and it is influenced greatly by The altitude and terrain. The local of easterly and westerly wind cycle appears under 2640.0 m above sea level. There are diurnal variations of east-west and north-south wind components between 1990.5 m and 2640.0 m above sea level. 2） The diurnal variation of air temperature showed single valley with the minimum value before sunrise, and single peak with the maximum value in afternoon and before sunset. 3） The diurnal variation of relative humidity showed one peak with the maximum around 22：00 and one valley with the minimum around 11：00 at higher than 3520.0 m above sea level, while one peak with the maximum between 07：00 and 08：00 and one valley with the minimum at 15：00 to 17：00 between 1975.4 m and 2640.0 m above sea level. 4） The diurnal variation of atmospheric pressure showed double-peak with its first and second peak values before noon and midnight respectively, while double-valleys with its first and second valley values before sunrise and sunset respectively. The causes of diurnal variation of meteorological elements were related to terrain environment, land and lake distribution, solar radiation and so forth. These provide important basic knowledge on the atmospheric structure, the landatmosphere exchange, and the local atmospheric circulation’s variation around the Tibetan Plateau.
作者
董保举
Dong Baoju(Dali National Climate Observatory, Dali 671003)
出处
《气象科技进展》
2017年第5期15-20,共6页
Advances in Meteorological Science and Technology
基金
云南省气象局科技项目(YB201210)
关键词
日变化
气象要素
云南大理
青藏高原
diurnal variation
meteorological elements
Yunnan Dali
Tibetan Plateau
