摘要
利用全国探空系统换型时获取的70个高空台站的对比观测数据,计算了59型探空仪和L波段探空仪温度和位势高度的差异,分析了探空仪换型对于探空数据一致性的影响。结果表明:就全国平均而言,在100 hPa特别是在400 hPa以下高度,两套系统提供的温度和位势高度观测值没有明显的系统差异;但在70 hPa以上高空,59型探空仪测定的规定等压面温度比L波段探空仪低0.1～0.7℃,导致位势高度在20 hPa高度时偏低达30 m左右,换型前后变化明显。系统差异的产生与59型探空仪的生产厂家、施放地区和季节关系较大,进一步分析表明:太原厂生产的探空仪测得的温度在对流层偏高,在平流层偏低,位势高度在对流层偏高,在平流层逐步转为偏低;上海厂生产的探空仪测得的温度全程偏低,引起位势高度也全程偏低,因此两个厂家的59型探空仪相对于L波段的温度和位势高度系统差也有明显不同。用户在使用局部地区高空站59型探空仪的观测数据时需了解该59型探空仪的生产厂家。
The radiosonde records such as upper air temperature,pressure and humidity are the fundamental data for weather forecasting and climate analysis,and especially for the latter,a long-term continuity and a good consistency of these records are also required.The radiosonde systems used in China have experienced three generations since 1950s.Improvements and updates of the equipment have significantly increased the sounding data acquisition rate,accuracy and reliability,but inconsistencies of historical data arise simultaneously. In order to analyze system deviation between the records obtained from the upper-air sounding records before and after applications of new equipment and method,comparison observations between the L-band radiosonde systems with 59 ones at 80 upper-air stations are conducted in 2002,and totally 60 records are obtained at each station using 60 normal operational 59 radiosonde systems and 60 L-band ones which are used for training.From those stations,the sounding data of 70 stations are selected and analyzed. The records of temperature and geopotential height of mandatory level obtained from two types radiosonde systems are compared,and the average deviations between the records of different systems are adopted to show the difference.Considering the data error,which is related to three manufacturers of 59 radiosonde, different solar-altitude and different temperature-profile,the records are classified for comparison by manufacturer of 59 type,observation time and launching site,etc. On the whole,below the 100 hPa height,the temperature difference is less than 0.3℃and the geopotential height difference is less than 7 meters.Therefore,before and after changing the sounding systems, the radiosonde records below the 100 hPa height do not exhibit obvious change in terms of the overall average. However,according the records higher than the 70 hPa height,the mandatory level temperature measured by 59 radiosonde is 0.1—0.7℃lower than that measured by L-band radiosonde,which results in a continuous cumulation of geopotential height difference with increasing height.For example,at the height of 20 hPa,the difference can reach about 30 meters,which is obvious. In summer,compared with the records of L-band radiosonde,those of 59 radiosonde made by Taiyuan factory show a significantly higher temperature in troposphere,and a significantly lower temperature beyond the top of troposphere,which brings on a higher geopotential height in troposphere（as much as 20 meters on average）,and a lower geopotential height in stratosphere（as much as 18 meters on average）. The records of 59 radiosonde made by Shanghai factory exhibit a little lower temperature and geopotential height in both troposphere and stratosphere（with a maximum difference of 37 meters）.In winter,59 radiosondes made by the two factories exhibit the same behavior as in summer respectively but with obvious small amplitudes.
出处
《应用气象学报》
CSCD
北大核心
2010年第2期214-220,共7页
Journal of Applied Meteorological Science
