Small-scale variability of temperature and LWC at Stratocumulus top

Physics of Stratocumulus Top (POST), a research campaign focused on a detailed study of processes occurring in the uppermost part of Sc cloud and capping Entrainment Interfacial Layer (EIL), was held in the vicinity of Monterey Bay in July and August 2008. The CIRPAS Twin Otter research aircraft, equipped to measure thermodynamics, microphysics, dynamics and radiation, collected unique data characterizing the cloud top region. Among them there are 1000 Hz (~5 cm spatial resolution) records of fluctuations of temperature from the Ultra Fast Thermometer (UFT) and of liquid water content (LWC) from the Particulate Volume Monitor (PVM). Selected examples of records revealing temperature and LWC structure in different stages of entrainment/mixing process will be presented. Structure functions and power spectral densities of temperature and LWC fluctuations in various regions of the the uppermost part of the cloud and of Entrainment Interface Layer will be analyzed in order to further illustrate variability of mixing process.