气象探空火箭气温测量不确定度评估方法

在气象火箭测温修正模型基础上,通过误差分析理论,对温度修正及其不确定度评估方法进行研究。根据火箭探空仪在空中下落过程中大气密度变化规律,建立温度修正数学模型,推导得到温度修正公式。根据误差理论,分析影响温度修正的八项误差因素,并逐项给出温度修正误差表达式。以气象火箭实测数据为例,运用上述公式,对探空火箭温度反演不确定度进行分析计算。结果表明:温度反演不确定度在50~60 km较大,最大为3.6 K；40~50 km不确定度为0.3~0.9 K；40 km以下,不大于0.3 K。影响温度不确定度的因素主要是气动加热修正项、滞后效应修正项、结构热传导修正项和传感器对环境热辐射修正项。数据处理时采用参考大气或标准大气仅进行一次修正是不够的,需进行迭代修正,单次修正结果与迭代修正结果差异最大可达5.6 K。

Evaluation method of the uncertainty of the temperaturemeasurement for meteorological sounding rocket

Based on the temperature correction model of meteorological sounding rocket, through error analysis theory, research on the method of temperature correction and uncertainty evaluation was conducted. According to the law of atmospheric density change during the falling process of rocketsonde, the mathematical model of temperature correction was established, and the formula of temperature correction was deduced. According to the error theory, eight error factors which affect the temperature correction were analyzed, and the expression of error in temperature correction was given one by one. Taking measured data as an example, using the above formula, the uncertainty of temperature inversion of sounding rocket was analyzed and calculated. The results show that the uncertainty of temperature inversion is larger in 50~60 km, and the maximum is 3.6 K; uncertainty in 40~50 km is 0.3~0.9 K; uncertainty in less than 40 km is no more than 0.3 K.The main factors that affect the uncertainty of temperature are aerodynamic heating correction, lag effect correction, structural heat conduction correction, and sensor correction for environmental heat radiation. It is not enough to use the reference atmosphere or the standard atmosphere for only single correction in data processing. Iterative correction is needed, and the maximum difference between iterative correction results and single correction results is 5.6 K.