High-spectral-resolution lidar with iodine-vapor filters: measurement of atmospheric-state and aerosol profiles.
High-spectral-resolution lidar with iodine-vapor filters: measurement of atmospheric-state and aerosol profiles.
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DOI：
10.1364/ao.40.005280
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发表时间：
2001-10
期刊：
影响因子：
1.9
通讯作者：
J. W. Hair;L. M. Caldwell;D. Krueger;C. She
中科院分区：
文献类型：
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作者：
J. W. Hair;L. M. Caldwell;D. Krueger;C. She
高光谱分辨率激光雷达可以同时测量大气温度、气压、气溶胶后向散射比和气溶胶消光系数的垂直剖面。我们用这些特征来描述一个系统。发射机是一个窄带（FWHM约为74 MHz），注入种子，脉冲，双YAG激光器，波长为532 nm。检测系统中的碘蒸气过滤器可将分子散射和气溶胶散射进行光谱分离，大大降低了气溶胶散射（-41 dB）。在选定的频率下工作，以利用蒸气过滤器中的两条相邻线，可以获得测量信号与空气温度比的灵敏度等于0.42%/K。使用一个相对较小的发射和接收系统（激光功率乘以望远镜孔径等于0.19 Wm(2)），我们在11个晚上测量的温度分布（0.5-15公里）与气球探测的温度分布一致，在2-5公里的高度范围内，温度分布在2.0 K以内。在递减率、对流层顶高度和逆温方面有很好的一致性。原则上，要反转信号，需要一个已知的密度在一个高度，但在实践中，它是方便的，也使用一个已知的温度在该高度。这是一个可扩展的系统，用于对流层和平流层下层的垂直温度剖面的高空间分辨率，即使在气溶胶存在的情况下也是如此。
A high-spectral-resolution lidar can measure vertical profiles of atmospheric temperature, pressure, the aerosol backscatter ratio, and the aerosol extinction coefficient simultaneously. We describe a system with these characteristics. The transmitter is a narrow-band (FWHM of the order of 74 MHz), injection-seeded, pulsed, double YAG laser at 532 nm. Iodine-vapor filters in the detection system spectrally separate the molecular and aerosol scattering and greatly reduce the latter (-41 dB). Operating at a selected frequency to take advantage of two neighboring lines in vapor filters, one can obtain a sensitivity of the measured signal-to-air temperature ratio equal to 0.42%/K. Using a relatively modest size transmitter and receiver system (laser power times telescope aperture equals 0.19 Wm(2)), our measured temperature profiles (0.5-15 km) over 11 nights are in agreement with balloon soundings to within 2.0 K over an altitude range of 2-5 km. There is good agreement in the lapse rates, tropopause altitudes, and inversions. In principle, to invert the signal requires a known density at one altitude, but in practice it is convenient to also use a known temperature at that altitude. This is a scalable system for high spatial resolution of vertical temperature profiles in the troposphere and lower stratosphere, even in the presence of aerosols.