A review of the remote sensing of lower tropospheric thermodynamic profiles and its indispensable role for the understanding and the simulation of water and energy cycles

Abstract

A review of remote sensing technology for lower tropospheric thermodynamic (TD) profiling is presented with focus on high accuracy and high temporal-vertical resolution. The contributions of these instruments to the understanding of the Earth system are assessed with respect to radiative transfer, land surface-atmosphere feedback, convection initiation, and data assimilation. We demonstrate that for progress in weather and climate research, TD profilers are essential. These observational systems must resolve gradients of humidity and temperature in the stable or unstable atmospheric surface layer close to the ground, in the mixed layer, in the interfacial layer-usually characterized by an inversion-and the lower troposphere. A thorough analysis of the current observing systems is performed revealing significant gaps that must be addressed to fulfill existing needs. We analyze whether current and future passive and active remote sensing systems can close these gaps. A methodological analysis and demonstration of measurement capabilities with respect to bias and precision is executed both for passive and active remote sensing including passive infrared and microwave spectroscopy, the global navigation satellite system, as well as water vapor and temperature Raman lidar and water vapor differential absorption lidar. Whereas passive remote sensing systems are already mature with respect to operational applications, active remote sensing systems require further engineering to become operational in networks. However, active remote sensing systems provide a smaller bias as well as higher temporal and vertical resolutions. For a suitable mesoscale network design, TD profiler system developments should be intensified and dedicated observing system simulation experiments should be performed.

A Backscatter Lidar Forward Operator for Particle-Representing Atmospheric Chemistry Models

“…Profiles of the radial wind speed can be obtained by Doppler-Lidar systems, e.g., (Banta et al, 2012). 15 While the number of sophisticated lidar instruments that provide thermodynamic data (Wulfmeyer et al, 2015) is still low, there are already automated aerosol lidar networks in operation in Europe and Asia Sugimoto et al, 2008). For example the German weather service (Deutscher Wetterdienst, DWD) maintained already in 2010 a network of about 36 automated ceilometer lidar (ACL) systems (Flentje et al, 2010a).…”

Effects of Dynamic Range and Sampling Rate of an Infrared Thermometer to the Accuracy of the Cloud Detection

“…The cloud amount, type, height, and microphysical properties are all necessary information to meet the requirements for studies of the processes, while an accurate detection of the cloud presence is the basic information to mitigate the interference. Much of the required information is provided from various means from spaceborne, airborne, and ground-based instrumentations; each has its own merits and disadvantages [1,2].…”

Diurnal variations in integrated water vapor derived from a GPS ground network in the Volga–Ural region of Russia

“…It is important to take into account the field of meteorological parameters with high spatial and temporal resolution. This gives one the chance to correctly consider these measurements in radiation models and in models of climate and weather forecasting (Wulfmeyer et al, 2015;Benjamin et al, 2010). Traditional techniques of IWV sounding such as radiosondes and satellite and ground-based radiometric systems give very limited data for the understanding of these processes.…”