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CASES-99计划（合作大气-表面交换研究-1999）的一部分，PI将使用悬挂在系绳风筝上的仪器，或在平静条件下，系绳飞艇上的仪器，在时间和高度上以高分辨率测量温度、压力、湿度和风速。case的目的是利用一系列地面仪器、遥感观测、一个60米高的仪器塔和两架仪器飞机，研究非常稳定的夜间边界的物理和动力学。风筝/飞艇系统的观测将提供高达约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。它还将提供在选定高度的温度和风速的时间序列，以允许观察瞬态事件，如间歇性的湍流爆发，强阵风和波浪运动。特别令人感兴趣的现象是低空喷流、波的不稳定性和夜间逆温气流的湍流混合。这些测量，结合仪器塔台、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，用于研究稳定边界层在整个垂直范围内的动力学。

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.