湖南省自动站与人工站相对湿度差异分析

Analysis on the Difference of Relative Humidity between Automatic Station and Manual Station in Hunan Province

摘要: 自2002年以来，湖南省各气象站陆续由人工观测改为自动观测，2010年开始全省的观测资料均采用自动站资料。人工站和自动站的各气象要素观测值均存在一定程度的差异，其中以相对湿度的差异最为显著。通过对比两者之间的差异发现：人工站的相对湿度观测值普遍较自动站高，全省97站平均的年平均湿度差值(人工站减去自动站)为3.5%，差值 ≥ 5%的台站数达到了30个，这种差异是由于传感器的不同造成的，人工观测中相对湿度的测量使用干湿球传感器，而自动观测使用的是湿敏电容传感器。人工站和自动站相对湿度的差值存在季节性波动，7~9月差值最大，1~3月最小，这与自动站的湿敏电容传感器在高温高湿情况下误差较大有关。另外，人工站和自动站相对湿度差值有逐年增大的趋势，这可能与湖南高温高湿天气较多，自动站的湿敏电容传感器长期在这种环境中使用误差增大，寿命缩短有关。

Abstract: Since 2002, the meteorological stations in Hunan Province have successively changed from manual observation to automatic observation, and the observation data of the whole province have adopted automatic station data since 2010. There are some differences in the observed values of meteorological elements between manual stations and automatic stations, among which the difference in relative humidity is the most significant. By comparing the differences between the two observations, it is found that the relative humidity observation value of artificial stations is generally higher than that of automatic stations. The average annual average humidity difference (manual stations minus automatic stations) of 97 stations in the province is 3.5%, and the number of stations with a difference above 5% has reached 30. This difference is caused by different sensors. The dry and wet ball sensor is used for the measurement of relative humidity in manual observation, while the humidity sensitive capacitance sensor is used for automatic observation. There are seasonal fluctuations in the difference in relative humidity between manual and automatic observation. The difference is the largest from July to September and the smallest from January to March, which is related to the large error of humidity sensitive capacitance sensor in the automatic station under the condition of high temperature and high humidity. In addition, the relative humidity difference tends to increase year by year, which may be related to hot and high humidity weather in Hunan, the long-term use of humidity sensitive capacitance sensor of the automatic station in such an environment will increase the error and shorten the service life.