The Stable Nocturnal Boundary Layer: Observations and Interpretation of Mesoscale Instability Processes and Small-Scale Turbulent Breakup in the Absence/Presence of a Nocturnal Jet

作为CASE-99计划(合作大气-地面交换研究-1999)的一部分，PI将在时间和高度上以高分辨率测量温度、压力、湿度和风速，使用悬挂在系住的风筝上的仪器，或者在平静的条件下，使用拴住的软式飞艇。CASES的目的是利用一系列地面仪器、遥感观测、一座60米长的仪表塔和两架仪表化飞机，研究非常稳定的夜间边界的物理和动力学。风筝/软式飞艇系统的观测将提供长达约2公里的垂直剖面，补充飞机测量，并填补塔顶和最低飞机高度之间的重要高度差距。它还将提供选定高度的温度和风速的时间序列，以便观察到瞬时事件，如阵发性湍流、强风和波动。特别令人感兴趣的现象是低层急流、波不稳定以及夜间逆温层空气的湍流混合。这些测量，加上仪表塔、飞机和遥感设备(雷达、激光雷达、风廓线仪)的同时观测，将构成一组极好的数据，用于研究整个垂直范围内稳定边界层的动态。

As part of the CASES-99 program (Cooperative Atmosphere-Surface Exchange Study-1999), the PI will measure the temperature, pressure, humidity, and wind velocity with high resolution in time and altitude using instruments suspended from a tethered kite or, in calm conditions, a tethered blimp. The purpose of CASES is to study the physics and dynamics of the very stable nocturnal boundary using an array of surface-based instruments, remote sensing observations, a 60-m instrumented tower, and two instrumented airplanes. Observations by the kite/blimp system will provide vertical profiles up to about 2 km, supplementing the aircraft measurements and filling the important altitude gap between the top of the tower and the minimum aircraft altitude. It will also provide time series of temperature and wind velocity at selected altitudes to permit the observation of transient events such as intermittent bursts of turbulence, strong gusts, and wave motions. Phenomena of special interest are low-level jets, wave instabilities, and the turbulent mixing of air across the nocturnal inversion. These measurements, in combination with simultaneous observations by the instrumented tower, the aircraft, and the remote sensing equipment (radars, lidars, wind profilers) will constitute an excellent set of data for studying the dynamics of the stable boundary layer throughout its entire vertical extent.