Abstract

The structure of the moist troposphere is characterized by horizontally extended layers with significant changes of humidity across the layers, and temperature inversions (the top of the atmospheric boundary layer (ABL), as well as other inversion layers in the free troposphere). In the presence ... Show moreThe structure of the moist troposphere is characterized by horizontally extended layers with significant changes of humidity across the layers, and temperature inversions (the top of the atmospheric boundary layer (ABL), as well as other inversion layers in the free troposphere). In the presence of convective clouds, the moist troposphere is characterized by turbulence. This study uses the COSMIC radio occultation (RO) signals transformed from time or space to impact parameter representation for monitoring these tropospheric structures. The phase of the transformed RO signal is used for detecting the mean vertical refractivity gradients (inversion layers). Fluctuations of the amplitude of the transformed RO signal are used for detecting of turbulence (moist convection). In the presence of a strong capping inversion, the turbulence is commonly limited by the inversion. In the absence of an inversion, moist convection can penetrate to large heights in the troposphere. Monitoring of both the inversion layers and the convective layers in the troposphere is important for understanding processes of convective transport in the troposphere, weather forecasts including storm development, aircraft operations, and radio wave propagation. RO observations, with possessing high vertical resolution, play an important role in identifying these layers. The six COSMIC satellites, which record L1 GPS RO signals in the troposphere in the open-loop mode, enable retrieval of the atmospheric profiles almost down to the surface, providing a unique opportunity for global observations of inversion layers and moist convection in the troposphere. Show less