Lidar Studies of Upper Atmosphere Composition and Dynamics

激光雷达技术的使用在测量110公里高度以下大气特性方面取得了重大进展。这是一个雷达探测几乎没有回波的地区，特别是在夜间。激光雷达提供空气分子后向散射的密度数据，从而测量背景密度、通过介质传播的密度波，并从密度随高度下降的速率提供温度数据。激光雷达可以调谐到特定原子共振散射的波长，对于钠激光雷达来说，高度和垂直轮廓的变化是垂直速度和波通过80-100公里区域的敏感指示器。该奖项是为了表彰在与其他科学家利用无线电和其他光学技术探测大气的一系列合作活动中升级和操作两个激光雷达的奖项。将增加测量中性铁、钙和电离钙层的共振散射的能力，并使用较新的高功率激光雷达进行白天测量。

The use of Lidar techniques has led to important advances in measuring properties of the atmosphere below 110 km altitude. This is a region where there is little return from radar probing, especially at night. The lidar provides density data from the backscattering on air molecules, and thus measures the background density, density waves propagating through the medium, and from the rate of density decrease with height, provides data on temperature. Lidars can be tuned to wavelengths resonantly scattered by specific atoms, and for sodium Lidars the changes in height and vertical profile are sensitive indicators of vertical velocity and of the passage of waves through the region 80-100 km. This award is for upgrading and operating two lidars in a series of cooperative campaigns with other scientists using radio and other optical techniques to probe the atmosphere. The capability will be added to measure resonant scattering from the layers of neutral iron and calcium and ionized calcium, and to make daytime measurements with the newer high power lidar.