Microwave Temperature Research Articles

A Precipitation Detection Method for MWTS-II Radiance Assimilation in Typhoon Simulation

FY-3C Microwave Temperature Sounder Ⅱ (MWTS-Ⅱ) lacks observations at 23.8 GHz, 31 GHz and 89 GHz, making it difficult to remove the data contaminated by precipitation in assimilation. In this paper, a fast forward operator based on the Community Radiative Transfer Model (CRTM) was used to analyze the relationship between the observation minus background simulation (O-B) and the cloud fractions in different MWTS-Ⅱ channels. In addition, based on the community Gridpoint Statistical Interpolation (GSI) system, the radiation brightness temperature of the MWTS-Ⅱ was assimilated in the regional Numerical Weather Prediction (NWP) model. In the process of assimilation, Visible and Infrared Radiometer (VIRR) cloud detection products were matched to MWTS-Ⅱ pixels for precipitation detection. For typhoon No. 18 in 2014, impact tests of MWTS-Ⅱ data assimilation was carried out. The results show that, though the bias observation minus analysis (O-A) of assimilated data can be reduced by quality control only with | O-B | < 3K; however, the O-A becomes much smaller while the precipitation detection is performed with Fvirr < 0.9 (VIRR cloud fraction threshold of 0.9). Besides, the change of the environmental field around the typhoon is more conducive to make the simulated track closer to the observation. The 72-hour typhoon track simulation error also shows that, after the precipitation detection, the error of simulated typhoon track is significantly reduced, which reflects the validity of a precipitation detection method based on a double criterion of | O-B | < 3K and Fvirr < 0.9.

Occurrence and fate of antimicrobial triclocarban and its transformation products in municipal sludge during advanced anaerobic digestion using microwave pretreatment

This study, for the first time, investigated the impact of microwave pretreatment on the fate of the pervasive antimicrobial triclocarban (TCC) that was already present in municipal sludge, before and during advanced anaerobic digestion (AD) under thermophilic and mesophilic conditions. A range of microwave temperature (80 and 160 °C) and exposure duration (1 and 30 min) configurations were studied by employing ten bench-scale anaerobic digesters fed with mixed sludge at three different solids retention times (SRTs) including 20, 12, and 6 days. Seasonal changes influenced the levels of TCC in municipal sludge sampled from a plant employing the biological nutrient removal. Initial batch pretreatment studies showed that microwave irradiation itself can achieve TCC removal efficiencies up to 30 ± 4 and 64 ± 5% at 80 and 160 °C, respectively. The control digesters utilizing un-pretreated mixed sludge showed limited TCC removals, between 18 and 32% and 11–26% respectively, under thermophilic and mesophilic temperatures. On the other hand, the highest TCC elimination (78 ± 2%) was obtained from the thermophilic digester utilizing microwaved sludge at 160 °C for 30 min at SRT of 12 days. The non-chlorinated carbanilide (a transformation product of TCC) was detected and quantified for the first time during conventional and microwave-pretreated anaerobic sludge digestion. The formation of carbanilide in biosolids through reductive dechlorination could be an indicator of efficient and complete TCC transformation. This research demonstrated that AD coupled with microwave pretreatment can be used to reduce environmental concentrations of TCC in municipal sludge and biosolids.

Impacts of AMSU-A inter-sensor calibration and diurnal correction on satellite-derived linear and nonlinear decadal climate trends of atmospheric temperature

Satellite microwave temperature sounding data have been widely used in the study of climate trends over the past decades. When merging advanced microwave sounding unit-A (AMSU-A) data from 1998 to 2017 from different satellites, brightness temperature observations can be affected by differences in the center frequency, incidence angle, and local equator crossing time (LECT) among the instruments. Atmospheric drag and gravity variations with latitude can also cause orbital drift that leads to changes in LECT of the same instrument. Inter-sensor calibration and diurnal correction are thus necessary before applying AMSU-A data to climate studies. In this study, AMSU-A data from the National Oceanic and Atmospheric Administration’s (NOAA’s) -15, -18, and -19 satellites and the European Organization for the Exploitation of Meteorological Satellites MetOp-A/-B collected during 1998–2017 were first inter-calibrated by a double difference method to remove inter-sensor biases. AMSU-A data from NOAA-18 was used as the reference for the double difference inter-sensor calibration. A diurnal correction was then applied to data over the Amazon rainforest to eliminate the effects of different LECTs. Finally, linear and nonlinear climate trends were calculated to show that warming (cooling) trends over the Amazon rainforest for window and tropospheric AMSU-A channels 1–8 and 15 (stratospheric channels 9–14) significantly decreased (increased) if inter-sensor calibration and a diurnal correction was applied. The nonlinear climate trends reveal more rapid warming trends for tropospheric sounding channels 3–7 and 15 and less rapid cooling trends for stratospheric channels 10–12 during 1998–2008 than during 2008–2017. Channels 1–2 (channel 13) have cooling (warming) and warming (cooling) trends before and after 2008, respectively.

Performance comparison of feedforward neural network training algorithms in modelling microwave pyrolysis of oil palm fibre for hydrogen and biochar production

AbstractMicrowave pyrolysis of oil palm fibre (OPF) was conducted to study the effect of microwave power, temperature, and nitrogen (N2) flow rate on the production of hydrogen and biochar. The effect of microwave power ranging from 400 to 900 W, reaction temperatures ranging from 450°C to 700°C, and N2 flow rates ranging 200 to 1,200 cm3 min−1 were investigated. The microwave power, reaction temperature, and N2 flow rates are directly proportional to hydrogen and inversely proportional to biochar yield. The characteristics of the biochar were analysed using CHNOS, scanning electron microscopy, and Brunauer–Emmett–Teller results. Central composite design was used to optimize the number of experiment. The optimized experimental datasets were used as inputs for developing a model that can predict the weight of hydrogen and biochar from microwave pyrolysis of OPF. A multilayer feedforward neural network model was developed by comparing the performance of 11 different types of backpropagation training algorithms. The 11 training algorithms belong to six classes, which are (a) additive momentum, (b) self‐adaptive learning rate, (c) resilient backpropagation, (d) conjugate gradient, (e) quasi‐Newton, and (f) Bayesian regulation (BR). Best performing training algorithm was selected based on the lowest error values computed. The objective of this research is to identify the most suitable training algorithm for this process. Levenberg–Marquardt and BR exhibited very good performance. BR exhibited best performance with lowest error values in predicting weight of hydrogen and biochar. The testing data error values for hydrogen weight is 0.216 root mean square error (RMSE), 0.144 mean absolute error (MAE), and 0.020 mean absolute percentage error (MAPE), and biochar is 0.886 RMSE, 0.489 MAE, and 0.019 MAPE. The optimum number of hidden neuron for this algorithm is 19 with mean square error 0.23. The biochar exhibits porous structure suggesting possible land application.

Functional deep eutectic solvent-based chaotic extraction of phycobiliprotein using microwave-assisted liquid-liquid micro-extraction from Spirulina (Arthrospira platensis) and its biological activity determination

The selective purification of phycocyanin from Spirulina was achieved using a potentail functional deep eutectic solvents (FDES). FDES were synthesized using carbohydrate glycerol as hydrogen bond acceptor and donor respectively. Thermophysical evaluation of FDES revealed a close interaction within the hydrogen bond donor and acceptor resulting in high density, refractive index and viscosity. The increase of temperature promotes relative linear reduction in values of the former two parameters and non-linear association with the viscosity. Microwave-assisted liquid-liquid microextraction favours the enrichment of phycocyanin to the top phase along with FDES. The linearity, limit of detection and level of quantification for phycocyanin was found to be 7–60, 11 and 85 μg/ml, respectively. A maximum yield 86% (w/w) was obtained at 6 min with the solid-substrate ratio of 23% (w/v) at microwave temperature of 348 K and FDES volume of 650 μl at 70% (v/v). The purity of concentrated extract was enhanced by ion exchange chromatography and the purified fractions were evaluated for antibacterial activity against Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, Zymomonas mobilis, Pseudomonas aeruginosa, and Bacillus cereus.

Effect of dielectric properties on heat transfer characteristics of rubber materials via microwave heating

The effects of dielectric properties on temperature distribution, heat flux density distribution, heating rate, heating efficiency and heating uniformity of rubber sheets via microwave heating were studied. Experimental and numerical simulation studies were carried out, the reliability of the simulation method was verified. The results demonstrated that the ability of rubber to absorb microwave energy and convert it into heat is significantly affected by dielectric constant and dielectric loss tangent. Different dielectric properties led to different electric field strength distributions in rubber sheets during microwave heating process, resulting in different electrical energy densities in the rubber sheets, eventually, different amounts of electric field energy can be converted into heat, resulting in different temperature distributions. The temperature distributions of rubber sheets are uneven. The temperature difference of rubber sheet increases with increasing heating time, but the growth rate of temperature difference decreases with increasing heating time. The higher the dielectric constant or loss tangent of rubber, the higher the microwave heating efficiency and temperature rise rate, but the more uneven the temperature distribution. The longer the heating time, the higher the average body temperature of rubber sheet, but the growth rate of the average body temperature decreases with increasing heating time. The heat flux density of rubber sheet was also significantly influenced by the dielectric properties, the maximum temperature gradient value is in the central area of the rubber sheet rather than in the hot spot area.

Tropical Cyclone Surface Pressure Field Estimation Using Satellite Passive Microwave Observations over the Oceans

AbstractThe real time and accurate estimation of tropical cyclone (TC) surface pressure fields is highly desired in TC forecasting and analysis. Using satellite passive microwave observations over the oceans, the retrieval of TC surface pressure fields was investigated in this study, and a new retrieval algorithm was developed. This algorithm uses brightness temperatures (TBs) and TB anomalies together to accurately estimate TC surface pressure fields. Considering the relative superiority of 118‐GHz radiometers in spatial resolution, this study not only used the measurements of 60‐GHz radiometer Advanced Technology Microwave Sounder (ATMS) but also the 118‐GHz radiometer Microwave Humidity and Temperature Sounder (MWHTS). The TC measurements from July 2015 to September 2018 and the corresponding Global Data Assimilation System (GDAS) Final (FNL) analysis data were used to develop and test the retrieval algorithm. The testing results show that the proposed method can estimate the surface pressure fields of a TC's core area (within a 2° radius from the center) with an accuracy of better than 4.0, 5.0, and 8.0 hPa for tropical depressions and tropical storms, typhoons or hurricanes, and severe typhoons or major hurricanes, respectively. In addition, an in situ comparison demonstrates that the accuracy of the retrieved central pressure is better than 6.0, 8.0, and 10.0 hPa for tropical depressions and tropical storms, typhoons or hurricanes, and severe typhoons or major hurricanes, respectively.

Accelerated screening of arsenic and selenium fractions and bioavailability in fly ash by microwave assistance

Huge amounts of fly ash (FA) can be annually produced in power plants. Fly ash always contains high levels of arsenic (As) and selenium (Se) due to the preconcentration of these two elements during coal combustion process. It would be much concerned to screen their fractions and potential environmental behaviors in fly ash for beneficial use and treatment. Fast and practical methods for this purpose are urgently needed. Two fast and effective microwave-assisted sequential extraction schemes (MASE) were developed for fast screening As and Se fractions in fly ash for the first time. The extraction parameters including microwave irradiation time, temperature and power energy were optimized by comparing the results from MASE and the conventional scheme (Wenzel method). The results indicate that the extraction efficiency of As and Se in various fractions can be significantly accelerated by microwave irradiation. The whole procedure operation time can be significantly reduced from 24.5 h to 44 min by microwave assistance compared with the conventional shaking schemes. The recoveries of As and Se in the various extracted fractions were all above 80% with relative standard deviations (RSDs) below 8%. The developed methods were further confirmed by the validation of the certified reference material GBW08401 and fly ash samples from six power plants. The developed MASE methods are practical and effective for fast screening arsenic and selenium fractions in fly ash samples.

The structure of galactic halos and the microwave temperature maps

The study of Planck microwave temperature maps toward several nearby spiral edge-on galaxies had revealed frequency-independent temperature asymmetry detection of Doppler origin in their halos. The contribution of the dust component to that effect is studied in this paper, particularly for the case of the M31 galaxy, using the models of dust emission and the phenomenological profiles of the dark matter configurations. The obtained results are in accordance with those inferred from the microwave temperature asymmetry data, thus indicating the possible contribution of dust, among other radiation mechanisms, in revealing the dark halo parameters.

Generalized Parametric Prediction Model of the Mean Radiative Temperature for Microwave Slant Paths in All-Weather Condition

The mean radiative temperature ( $T_{mr}$ ) is a key function controlling the sky noise temperature in microwave receiving systems. A generalized parametric prediction (GPP) model of $T_{mr}$ for microwave slant paths in all-weather conditions is formulated and presented. The proposed GPP model is aimed at being multifrequency and surface-temperature scaled, valid for elevation angles from 5° to 90° and for frequencies ranging from 5 to 95 GHz within the three transmission windows delimited by the water vapor and the oxygen absorption peaks. The core of the GPP model is a parametrization driven by a physically based radiative transfer approach taking into account extinction, emission, and multiple scattering. The expression of $T_{mr}$ is normalized to the surface temperature of the considered site. The GPP model is verified with measurements available from the multiinstrument Italian Satellite (ITALSAT) campaign in Spino d’Adda, Milan, Italy, in 1994–1997, obtaining a fractional mean error ranging from 0.045 to 0.068. A comparison of the GPP model with the current ITU-R model shows a reduction in the root mean square error up to about 20 and 30 K, depending on the considered frequency.

Power Pulsing To Maximize Vibrational Excitation Efficiency in N2 Microwave Plasma: A Combined Experimental and Computational Study

Plasma is gaining increasing interest for N2 fixation, being a flexible, electricity-driven alternative for the current conventional fossil fuel-based N2 fixation processes. As the vibrational-induced dissociation of N2 is found to be an energy-efficient pathway to acquire atomic N for the fixation processes, plasmas that are in vibrational nonequilibrium seem promising for this application. However, an important challenge in using nonequilibrium plasmas lies in preventing vibrational-translational (VT) relaxation processes, in which vibrational energy crucial for N2 dissociation is lost to gas heating. We present here both experimental and modeling results for the vibrational and gas temperature in a microsecond-pulsed microwave (MW) N2 plasma, showing how power pulsing can suppress this unfavorable VT relaxation and achieve a maximal vibrational nonequilibrium. By means of our kinetic model, we demonstrate that pulsed plasmas take advantage of the long time scale on which VT processes occur, yielding a very pronounced nonequilibrium over the whole N2 vibrational ladder. Additionally, the effect of pulse parameters like the pulse frequency and pulse width are investigated, demonstrating that the advantage of pulsing to inhibit VT relaxation diminishes for high pulse frequencies (around 7000 kHz) and long power pulses (above 400 μs). Nevertheless, all regimes studied here demonstrate a clear vibrational nonequilibrium while only requiring a limited power-on time, and thus, we may conclude that a pulsed plasma seems very interesting for energy-efficient vibrational excitation.

Rotating baryonic dark halos

Galactic halos are of great importance for our understanding of both the dark matter nature and primordial non-Gaussianity in the perturbation spectrum, a powerful discriminant of the physical mechanisms that generated the cosmological fluctuations observed today. In this paper we analyze Planck data towards the galaxy M 104 (Sombrero) and find an asymmetry in the microwave temperature which extends up to about 1° from the galactic center. This frequency-independent asymmetry is consistent with that induced by the Doppler effect due to the galactic rotation and we find a probability of less than about 0.2% that it is due to a random fluctuation of the microwave background. In addition, Planck data indicate the relatively complex dynamics of the M 104 galactic halo, and this appears to be in agreement with previous studies. In view of our previous analysis of the dark halos of nearby galaxies, this finding confirms the efficiency of the method used in revealing and mapping the dark halos around relatively nearby edge-on galaxies.

Rapid microwave assisted derivatization of nitrofuran metabolites for analysis in shrimp by high performance liquid chromatography-fluorescence detector

A sensitive analytical method was proposed based on high-performance liquid chromatography with fluorescence detection coupled with microwave-assisted derivatization for the quantitative analysis of nitrofurans metabolites in shrimp samples. A novel derivatization reagent, 4-(acridone-10-yl)benzaldehyde, was synthesized and applied to the derivatization of several common nitrofurans metabolites (semicarbazide, 1-aminohydantoin, 3-amino-2-oxazolidinone, and 3-amino-morpholinomethyl-2-oxazolidinone). The influences of microwave power, irradiation time and temperature on the derivatization efficiency were investigated using Box-Behnken design. Moreover, microwave-assisted derivatization can obtain higher derivatization yields in a shorter period of time. Under the optimized conditions, the derivatization was achieved within 7.2 min. Lower limits of detection were obtained ranging from 0.20 to 0.28 μg/kg for all nitrofurans metabolites compounds. Satisfactory recoveries were obtained ranging from 90.5 to 103.6%. The developed method was successfully applied to the determination of four nitrofurans metabolites in shrimp. Furthermore, this developed method should offer great potential to the analysis of nitrofurans metabolites in foodstuffs.

Verification of Fengyun-3D MWTS and MWHS Calibration Accuracy Using GPS Radio Occultation Data

The newly launched Fengyun-3D (FY-3D) satellite carries microwave temperature sounder (MWTS) and microwave humidity sounder (MWHS), providing the global atmospheric temperature and humidity measurements. It is important to assess the in orbit performance of MWTS and MWHS and understand their calibration accuracy before using them in numerical weather prediction and many other applications such as hurricane monitoring. This study aims at quantifying the biases of MWTS and MWHS observations relative to the simulations from the collocated Global Positioning System (GPS) radio occultation (RO) data. Using the collocated FY-3C Global Navigation Satellite System Occultation Sounder (GNOS) RO data under clear-sky conditions as inputs to Community Radiative Transfer Model (CRTM), brightness temperatures and viewing angles are simulated for the upper level sounding channels of MWTS and MWHS. In order to obtain O − B statistics under clear sky conditions, a cloud detection algorithm is developed by using the two MWTS channels with frequencies at 50.3 and 51.76 GHz and the two MWHS channels with frequencies centered at 89 and 150 GHz. The analysis shows that for the upper air sounding channels, the mean biases of the MWTS observations relative to the GPS RO simulations are negative for channels 5–9, with absolute values < 1 K, and positive for channels 4 and 10, with values < 0.5 K. For the MWHS observations, the mean biases in brightness temperature are negative for channels 2–6, with absolute values < 2.6 K and relatively small standard deviations. The mean biases are also negative for channels 11–13, with absolute values < 1.3 K, but with relatively large standard deviations. The biases of both MWTS and MWHS show scan-angle dependence and are asymmetrical across the scan line. The biases for the upper air MWTS and MWHS sounding channels are larger than those previously derived for the Advanced Technology Microwave Sounder.

Optimization of process parameters of microwave processed PLLA/coir composites for enhanced mechanical behavior

In the present work, poly-L-lactide (PLLA)/coir-based polymer composites were fabricated by a novel manufacturing route of microwave processing. Microwave processing is faster and cleaner process as compare to conventional manufacturing processes. The effect of microwave temperature, time and fibre weight reinforcement was evaluated for their mechanical behaviour using uniaxial tension and flexural tests. The full factorial design was used to optimize the process parameters for enhanced mechanical performance of the composites. The analysis of results was done on Design Expert V.10 software. PLLA/coir composite processed at 140 °C for 12 min having fibre weight percentage of 30% has maximum tensile strength of 18 MPa. The maximum flexural strength 48 MPa reported was for the same specimen having maximum tensile strength. The optimized value of process parameters obtained was, processing temperature: 140°C, time 12 min and coir reinforcement percentage of 30%. The fractured specimens were characterised using scanning electron microscopy to support the results.

Striping Noise Analysis and Mitigation for Microwave Temperature Sounder-2 Observations

The Microwave Temperature Sounder (MWTS)-2 has a total of 13 temperature-sounding channels with the capability of observing radiance emissions from near the surface to the stratosphere. Similar to the Advanced Technology Microwave Sounder (ATMS), striping pattern noise, primarily in the cross-track direction, exists in MWTS-2 radiance observations. In this study, an algorithm based on principal component analysis (PCA) combined with ensemble empirical mode decomposition (EEMD) is described and applied to MWTS-2 brightness temperature observations. It is arguably necessary to smooth the first three principal component (PC) coefficients by removing the first four intrinsic mode functions (IMFs) using the EEMD method (denoted as PC3/IMF4). After the PC3/IMF4 noise mitigation, the striping pattern noise is effectively removed from the brightness temperature observations. The noise level in MWTS-2 observations is significantly higher than that detected in ATMS observations. In May 2014, the scanning profile of MWTS-2 was adjusted from varying-speed scanning to constantspeed scanning. The impact on striping noise levels brought on by this scan profile change is also analyzed here. The striping noise in brightness temperature observations worsened after the profile change. Regardless of the scan profile change, the striping noise mitigation method reported in this study can more or less suppress the noise levels in MWTS-2 observations.

Experimental and computational investigation of heat transfer in a microwave-assisted flow system

Microwave technology is gaining popularity as a tool for chemical process intensification and an alternative to conventional heating. However, in flow systems non-uniform temperature profiles are commonly encountered and hence methods to characterise and improve them are required. In this work, we studied the effects of various operational parameters - microwave power, inlet flow rate, tube orientation and pressure - on the electric field and temperature profiles of water flowing in a PTFE tube (2.4 mm internal diameter), placed in a commercial single-mode microwave applicator. A finite element model was developed to estimate the longitudinal temperature profiles and the absorbed microwave power, while in situ temperature monitoring was performed by a fibre optic probe placed at multiple locations inside the tube. The water temperature inside the tube increased by increasing the microwave power input and temperature profiles stabilised beyond 20 W, while the percentage absorbed microwave power showed the inverse trend. When changing the tube orientation or decreasing the inlet flow rate, microwave absorption decreased significantly. When the pressure was increased to 2.3 bara, water temperature increased by ∼20 °C. Results from this study provide valuable insights on achievable temperature profiles and energy efficiency of microwave-assisted flow synthesis systems.

Osteogenic effects of magnesium substitution in nano-structured β-tricalcium phosphate produced by microwave synthesis

β-Tricalcium phosphate (β-TCP) is an ideal bone repairing biomaterial because of its biocompatibility and biodegradability. Microwave irradiation provides rapid and homogeneous energy throughout the volume, which makes it possible to get smaller and uniform particles. Magnesium (Mg), as an indispensable element in human body, plays an important role in osteogenesis. The aim of this work was to explore the influence of microwave irradiation time and temperature on Mg-doped β-TCP (Mg-TCP) synthesis. It was found that smaller and more homogeneous particles were obtained after microwave irradiation. On the other hand, microwave irradiation increased the defects in crystal grains and caused agglomeration of particles. According to the characterization results, the microwave operation parameters were determined as 40 °C and 20 min. Then β-TCP with different Mg substitution contents (0, 5, 10 and 14 mol%) were synthesized in the parameters. The results revealed that Mg was incorporated into β-TCP as designed and the substitution did not change the phase structure notably except for reducing of cell parameters and lattice volume. Osteogenesis in vitro was performed on bone marrow mesenchymal stem cells of rats to discuss the influence of Mg-TCP on cells proliferation and differentiation. It was found that Mg14-TCP showed the best facilitation on proliferation and differentiation, and the promotion effects of Mg5- and Mg10-TCP were suppressed by deposition of the ions dissolved in medium on ceramic samples.

A New Method for Simulation of Lunar Microwave Brightness Temperatures and Evaluation of Chang'E‐2 MRM Data Using Thermal Constraints From Diviner

AbstractWe used the bolometric brightness temperatures (TBol) derived from the Lunar Reconnaissance Orbiters Diviner Lunar Radiometer (Diviner) as an upper boundary condition in our thermal model. We then calculated temperature profiles at any local time based on our improved thermal model at low to middle latitudes (70° N/S). Based on the temperature profiles, we modeled the midnight brightness temperature at 19.35 (TB19) and 37 GHz (TB37). Comparing to the Chang'E‐1 and Chang'E‐2 (CE‐1/2) observations, we found that CE‐1 showed a better data quality than that of CE‐2, especially for the TB37 data. Assuming that the issue with the CE‐2 data is caused by heat contamination of the cold‐reference antennas, we performed an empirical normalization of the CE‐2 microwave radiometer data near midnight following the approach of Hu et al. (2017). The results show that TB difference (modeled values minus modified TB) for 19.35 GHz is less than 3.40 K for ∼80% of the pixels. At 37 GHz, ∼67% of the pixels have TB difference less than 2.88 K. Additionally, we identified some areas of low microwave temperature in our modified TB maps. These low‐TB features can be characterized by two types: (1) low TB spots at fresh craters with high rock abundance and bright rays and (2) high‐Ti lunar mare surfaces with a low content of rock fragments. Investigating these low‐TB regions with the modified TB data can reveal more information about subsurface thermal regime and properties and help us better understand the evolution of regolith on the Moon.

Atmospheric Retrievals and Assessment for Microwave Observations from Chinese FY-3C Satellite during Hurricane Matthew

The evolution process of hurricane Matthew (NO. 8, 2016) was simulated using the mesoscale Weather Research and Forecasting (WRF) model at temporal resolution of 5 min and spatial resolution of 15 km. The atmospheric temperature and humidity profiles were retrieved accordingly for diagnostic analysis of the short-term heavy rainstorm. The satellite-based microwave observations from Microwave Humidity and Temperature Sounder (MWHTS) instrument on board the FY-3C polar-orbiting satellite were matched with the WRF grid points. In particular, the in-orbit calibration and data quality control are detailed, and an innovative method combining artificial neural network (ANN) and 1-D variational approach is presented to derive the high-performance retrieval profiles. Results show that the root-mean-square errors of the retrieved temperature and water vapor density profiles are 0.75 K and 0.41 g/m3, respectively. In addition, this study used both the retrievals and radiance from MWHTS as input to the WRF Data Assimilation (WRFDA) model to forecast the track and intensity of hurricane Matthew. The forecast results were cross-compared with the best track to verify the radiance quality and performance of the retrievals, especially for the 118 GHz channel, which was firstly used in meteorological satellite.