自动与人工观测气压的差异及原因分析

Difference Analysis Between Automatic and Manual Atmospheric Pressure Measurements

利用全国373个基准基本站自动与人工平行观测期间的气压对比观测资料,进行了自动与人工观测气压的差异分析,重点从本站气压计算公式和环境温度方面分析了两种观测方式引起气压观测数据差异的原因。结果表明:(1)自动观测的气压值比人工观测气压值普遍偏低0.1～0.2 hPa。日最低气压差异最大,可达到0.34 hPa。自动与人工观测气压的差值有较明显的日变化和季节变化;(2)从分布区域看,自动与人工观测气压差异较大的区域位于海拔较高的西部地区,我国中东部地区则差异较小,绝大多数在0.2 hPa以内;(3)由于人工观测气压计算公式的问题,在2004年之前人工观测的本站气压值偏大,海拔高度越高的地方,偏大程度越高。统计结果还表明,30℃以上的高温环境和-30℃以下的低温环境,自动与人工观测气压差异明显。

Based on the atmospheric pressure data from 2001 to 2007 during parallel observation,analyses have been made on the differences between automatic-observed and manual-observed atmospheric pressure data,especially the cause of differences is discussed.The results show that most automatic-observed pres sure data are less than manual-observed pressure data.And the higher the sea level elevation is,the more evident the differences are.Because of systematic error in manual pressure formula,the manual pressure data before 2004 are larger than that after 2004.There are obvious daily variation and annual variation in pressure differences.In the higher temperature of period or month,the pressure difference is great al ways.The statistic results show when the temperature is higher than 30℃or below -30℃,the differences between manual and automatic pressure measurements are considerably obvious.