L波段与701-400M探空系统观测资料比较评估

Comparative Assessment of Observation Data between L-Band and 701-400M Sounding Systems

利用四川达州站在701-400 M探空系统向L波段雷达GTS1-2型电子探空仪系统转变时的对比观测资料进行了评估分析.结果表明：温度平均差值为-0.28℃,200 hPa以下平均差值为-0.05℃,200 hPa以上平均差值为-0.52℃,换型带来的温度变化还是明显的;直接差异的80.1％在-1.0～1.0℃间.位势高度平均差值为-7.63 gpm,100 hPa以下高度平均偏低-1.13 gpm,100 hPa以上高度平均偏低-19.57 gpm,换型带来的位势高度变化还是明显的;直接差异的89.0％在-50～10 gpm间.湿度平均差值为-2％,直接差异的87.2％在-20％～～10％间.风向平均差值为1.0°,直接差异的80.1％在-10°～～10°间.风速平均差值为0.3 m/s,直接差异的95.0％在-5～5 m/s间.就平均差值来看,温度、位势高度、湿度是L波段系统所测值低于701-400 M系统所测值,而风向、风速则反之.换型造成各要素差异的峰值还是较大.由于两套系统所使用的设备、探空仪的制造、测量精度、施放、接收等方面的不同,都会引起测量值出现差异,但对各要素的影响确有所不同.

A comparative assessment is made of the observation data from the L-band radar sounding system and 701-400M sounding system at Dazhou Station in Sichuan. The results indicate that the average temperature difference is -- 0.28 ℃ ; that below 200 hPa height is -- 0.05 ℃, and that above 200 hPa height is --0.52 %. The temperature data change resulted from sounding system change is obvious; 80.1% of temperature differences are between --1.0 ℃ and 1.0 ℃, The average geopotential height difference is --7.63 gpm; that below 100 hPa height is --1.13 gpm, and that above 100 hPa height is --19.57 gpm. The geopotential height data change resulted from sounding system change is obvious; 89.0% of geopotential height difference is between --50 gpm and 10 gpm. The average relative humidity difference is -2%; 87.2% of relative humidity differences are between -20% and 10%. The average wind direction difference is 1.0°; 80.1 % of the differences, are between -10° and 10%. The average wind velocity difference is 0.3 m/s; 95% of wind velocity differencs are between --5 m/s and 5 m/s. According to the average differences, the temperature, geopotential height, and relative humidity measurements from the L band sounding system are lower than those measured by the 701-400 M sounding system, but wind direction and velocity measurements from the Lband sounding system are higher than those measured by the 701- 400 M sounding system. The peak difference is large because of sounding system change. （）wing to the differences of equipment, sounder manufacturing, measurement accuracy, sounder launching, message receiving, etc., the observational data are different, but influences on various elements are different.