Ice clouds play a critical role in the balance of earth–atmosphere radiation system, but there are some limitations existing remote sensing methods for ice clouds. Terahertz wave is expected to be best waveband retrieving clouds, with terahertz wavelengths order size typical cloud particles. An inversion method at based on genetic algorithm proposed this paper. First, suitable channel sets band, which mainly combination absorption lines and window regions, determined. Then, improve...

Abstract. Currently, terahertz remote sensing technology is one of the best ways to detect microphysical properties ice clouds. Influenced by representativeness crystal scattering (ICS) model, existing cloud inversion algorithms still have significant uncertainties. In this study, based on Voronoi ICS we developed a algorithm water path (IWP) and median mass diameter (Dme) This study utilized single-scattering (extinction efficiency, albedo, asymmetry factor) Voronoi, sphere, hexagonal...

Rainfall inversion based on commercial microwave links (CMLs) has been extensively studied and experimented. However, as necessary part of inversion, the error caused by <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">A - R</i> relationship is lack systematic evaluation. Based measured raindrop size distribution (RSD) data recorded a disdrometer, theoretical rain-induced attenuation rainrate are calculated, this basis, between inversed from...

A retrieval methodology based on the Bayesian neural network (BNN) is presented that inverts ice water path (IWP), mean mass-weighted diameter (D <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">me</sub> ), and cloud height of clouds from sub-millimeter radiometer observations. The training dataset was created using collecting profiles DARDAR (raDAR/liDAR) database running simulations by Atmospheric Radiative Transfer Simulator (ARTS) model....

Retrieval of ice cloud properties using passive terahertz wave radiometer from space has gained increasing attention currently. A multi-channel regression inversion method for remote sensing water path (IWP) in the band is presented. The characteristics upward radiation clear-sky and cloudy-sky are first analyzed Atmospheric Radiative Transfer Simulator (ARTS). Nine representative center frequencies with different offsets selected to study changes caused by microphysical parameters clouds....

Cirrus clouds play an important role in the energy budget and hydrological cycle of atmosphere. It is still one largest uncertainties global climate change studies. This mainly attributable to measurement discrepancies cirrus parameters, especially microphysical which are constrained by existing methods. With THz wavelengths on order size typical cloud particles therefore being sensitive clouds, region expected have a promising prospect concerning measuring parameters (ice water path...

Abstract The characteristics of two natural positive cloud‐to‐ground flashes are analyzed in detail with the broadband very high frequency (VHF) mapping system. bidirectional leader processes at lightning initiation observed, negative leaders propagating upward and downward. downward can be divided into stages, scattered slowly extending sources first stage more concentrated faster second stage. overall extension speeds stages 1.8 × 10 4 2.7 m/s for flashes, 7.8 5 1.0 6 m/s, respectively....

Cirrus is an important regulator for the flow of radiant energy in earth-atmosphere system through processes scattering and absorption radiation. In order to satisfy urgent requirement accurate retrieval cirrus microphysical properties, terahertz wave expected be best waveband inverting particle size ice water path, with wavelengths on typical particles. There need establishing stable inversion method. A new method path developed based multiple lookup tables spaceborne measurements...

Abstract The wire destruction and plasma channel reestablishment process during the initial stage of a triggered lightning is analyzed based on comprehensive observations, including very high frequency (VHF) mapping array, electric‐magnetic field, high‐speed video. detailed discharge processes in both attempted reconnection are firstly evidenced by VHF results. similar to leader/return‐stroke sequence, while involves more complicated discharges. It shown that several segments fused due...

This article presents a new method for retrieving the Ice Water Path (IWP), median volume equivalent sphere diameter (Dme) of thin ice clouds (IWP &lt; 100 g/m2, Dme 80 μm) in Terahertz band. The upwelling brightness temperature depressions caused by at 325.15, 448.0, 664.0 and 874.0 GHz channels are simulated Atmospheric Radiative Transfer Simulator (ARTS). forward radiative transfer models taken as historical data M5 model tree algorithm to construct set piecewise functions which represent...

Abstract Spaceborne passive submillimeter instruments can provide higher sensitivity to a broader size range of ice hydrometeors than traditional millimeter and infrared observations. However, plane‐parallel cloud assumption is commonly applied for simplicity in retrieval algorithms, while observations from active have already demonstrated the particle variabilities vertical dimension. This study conducted assess impacts inhomogeneity on submillimeter‐wave simulations. Specifically,...

Scattering process of aerosol particles plays an important role in atmospheric radiative transfer since it can modify the transmission, reflection and absorption ability system. Owning to uncertainty particles' scattering properties, which results from their complicated geometries inhomogeneous compositions, there still exists a considerable numerical simulation, simulating properties with irregular shapes has become hotspot meteorological study. To this end, new model is developed based on...

PSTD (pseudospectral time domain) is recognized as one of the powerful models to accurately calculate scattering properties nonspherical particles. But it only good at computation in coarse spatial resolution, and large "staircase approximation error" will occur actual computation. To solve this problem, variable dimension scheme introduced improve computation, which, finer grid cells are set near particle's surface. In order ensure that algorithm can be performed on non-uniform grids, we...

The invariant imbedding (IIM) T-matrix method has shown great potential in light scattering field. However, the need to be calculated through matrix recurrence formula derived from Helmholtz equation, thus its computational efficiency is much lower than Extended Boundary Condition Method (EBCM). To alleviate this problem, Dimension-Variable Invariant Imbedding (DVIIM) presented paper. Compared with traditional IIM model, dimensions of and relevant matrices are gradually increasing as...

Objective To probe the relationship between expression of TL1A and level IFN-γ secreted by T cells in acute stage Guillain-Barre syndrome (GBS). Methods ① Six-week female Bal b/c mice were immunized purified recombinant human soluble TNF-like molecular 1A (rhsTL1A) protein. The polyclonal antibody against rhsTL1A was identified immunofluorescence using umbilical vein epithelial (HUVEC). ② detect biologic activity rhsTL1A, peripheral blood mononuclear (PBMC) from healthy donors separated...